Science.gov

Sample records for optimized surgical techniques

  1. Surgical forceps techniques.

    PubMed

    Malden, N

    2001-01-01

    This paper considers two new elevator and dental forceps techniques for the atraumatic removal of teeth to avoid a surgical procedure where possible. The techniques described should be applicable in relatively well defined but commonly occurring situations. The two techniques involve the unconventional use of conventional dental extraction forceps, with the aim of facilitating removal of the retained roots of certain teeth: the first for incisors, canines and premolars and the second for lower first molars. The term 'surgical forceps technique's is tentatively put forward as a description of these hybrid procedures. PMID:11819949

  2. Laparoscopy in the morbidly obese: physiologic considerations and surgical techniques to optimize success.

    PubMed

    Scheib, Stacey A; Tanner, Edward; Green, Isabel C; Fader, Amanda N

    2014-01-01

    The objectives of this review were to analyze the literature describing the benefits of minimally invasive gynecologic surgery in obese women, to examine the physiologic considerations associated with obesity, and to describe surgical techniques that will enable surgeons to perform laparoscopy and robotic surgery successfully in obese patients. The Medline database was reviewed for all articles published in the English language between 1993 and 2013 containing the search terms "gynecologic laparoscopy" "laparoscopy," "minimally invasive surgery and obesity," "obesity," and "robotic surgery." The incidence of obesity is increasing in the United States, and in particular morbid obesity in women. Obesity is associated with a wide range of comorbid conditions that may affect perioperative outcomes including hypertension, atherosclerosis, angina, obstructive sleep apnea, and diabetes mellitus. In obese patients, laparoscopy or robotic surgery, compared with laparotomy, is associated with a shorter hospital stay, less postoperative pain, and fewer wound complications. Specific intra-abdominal access and trocar positioning techniques, as well as anesthetic maneuvers, improve the likelihood of success of laparoscopy in women with central adiposity. Performing gynecologic laparoscopy in the morbidly obese is no longer rare. Increases in the heaviest weight categories involve changes in clinical practice patterns. With comprehensive and thoughtful preoperative and surgical planning, minimally invasive gynecologic surgery may be performed safely and is of particular benefit in obese patients. PMID:24100146

  3. Optimal Suturing Technique and Number of Sutures for Surgical Implantation of Acoustic Transmitters in Juvenile Salmonids

    SciTech Connect

    Deters, Katherine A.; Brown, Richard S.; Boyd, James W.; Eppard, M. B.; Seaburg, Adam

    2012-01-02

    The size reduction of acoustic transmitters has led to a reduction in the length of incision needed to implant a transmitter. Smaller suture knot profiles and fewer sutures may be adequate for closing an incision used to surgically implant an acoustic microtransmitter. As a result, faster surgery times and reduced tissue trauma could lead to increased survival and decreased infection for implanted fish. The objective of this study was to assess the effects of five suturing techniques on mortality, tag and suture retention, incision openness, ulceration, and redness in juvenile Chinook salmon Oncorhynchus tshawytscha implanted with acoustic microtransmitters. Suturing was performed by three surgeons, and study fish were held at two water temperatures (12°C and 17°C). Mortality was low and tag retention was high for all treatments on all examination days (7, 14, 21, and 28 days post-surgery). Because there was surgeon variation in suture retention among treatments, further analyses included only the one surgeon who received feedback training in all suturing techniques. Incision openness and tissue redness did not differ among treatments. The only difference observed among treatments was in tissue ulceration. Incisions closed with a horizontal mattress pattern had more ulceration than other treatments among fish held for 28 days at 17°C. Results from this study suggest that one simple interrupted 1 × 1 × 1 × 1 suture is adequate for closing incisions on fish under most circumstances. However, in dynamic environments, two simple interrupted 1 × 1 × 1 × 1 sutures should provide adequate incision closure. Reducing bias in survival and behavior tagging studies is important when making comparisons to the migrating salmon population. Therefore, by minimizing the effects of tagging on juvenile salmon (reduced tissue trauma and reduced surgery time), researchers can more accurately estimate survival and behavior.

  4. Neuronavigation. Principles. Surgical technique.

    PubMed

    Ivanov, Marcel; Ciurea, Alexandru Vlad

    2009-01-01

    Neuronavigation and stereotaxy are techniques designed to help neurosurgeons precisely localize different intracerebral pathological processes by using a set of preoperative images (CT, MRI, fMRI, PET, SPECT etc.). The development of computer assisted surgery was possible only after a significant technological progress, especially in the area of informatics and imagistics. The main indications of neuronavigation are represented by the targeting of small and deep intracerebral lesions and choosing the best way to treat them, in order to preserve the neurological function. Stereotaxis also allows lesioning or stimulation of basal ganglia for the treatment of movement disorders. These techniques can bring an important amount of confort both to the patient and to the neurosurgeon. Neuronavigation was introduced in Romania around 2003, in four neurosurgical centers. We present our five-years experience in neuronavigation and describe the main principles and surgical techniques. PMID:20108488

  5. Surgical technique affects outcomes in acromioclavicular reconstruction.

    PubMed

    Grassbaugh, Jason A; Cole, Chad; Wohlrab, Kurt; Eichinger, Josef

    2013-01-01

    Optimal treatment for acromioclavicular (AC) dislocation is unknown. Numerous surgical procedures for AC injuries have been described with little comparison. This study sought to compare the clinical and radiographic results of various surgical techniques in order to identify the optimal surgical technique. Ninety patients met inclusion criteria of AC reconstruction at this institution. A retrospective review of outcomes was performed using the electronic records system. Radiographs were measured for pre- and postoperative grade and percent elevation versus the contralateral side. Overall revision rate was 9%. Suture button fixation had a revision rate of 0% compared to 14% (p = .01). Reconstruction procedures performed with distal clavicle excision showed a higher revision rate, 17% compared to 0% (p = .003). There were no statistically significant clinical differences. AC reconstructions performed with suture button construct were superior to other surgical techniques. Procedures performed with distal clavicle excision were inferior to those without. PMID:23449059

  6. Development of a Surgically Optimized Graft Insertion Suture Technique to Accommodate a Tissue-Engineered Tendon In Vivo

    PubMed Central

    Sawadkar, Prasad; Alexander, Susan; Tolk, Marten; Wong, Jason; McGrouther, Duncan; Bozec, Laurent

    2013-01-01

    Abstract The traumatic rupture of tendons is a common clinical problem. Tendon repair is surgically challenging because the tendon often retracts, resulting in a gap between the torn end and its bony insertion. Tendon grafts are currently used to fill this deficit but are associated with potential complications relating to donor site morbidity and graft necrosis. We have developed a highly reproducible, rapid process technique to manufacture compressed cell-seeded type I collagen constructs to replace tendon grafts. However, the material properties of the engineered constructs are currently unsuitable to withstand complete load bearing in vivo. A modified suture technique has been developed to withstand physiological loading and off load the artificial construct while integration occurs. Lapine tendons were used ex vivo to test the strength of different suture techniques with different sizes of Prolene sutures and tissue-engineered collagen constructs in situ. The data were compared to standard modified Kessler suture using a standard tendon graft. Mechanical testing was carried out and a finite element analysis stress distribution model constructed using COMSOL 3.5 software. The break point for modified suture technique with a tissue-engineered scaffold was significantly higher (50.62 N) compared to a standard modified Kessler suture (12.49 N, p<0.05). Distributing suture tension further proximally and distally from the tendon ends increased the mechanical strength of the repairs. We now have ex vivo proof of concept that this suture technique is suitable for testing in vivo, and this will be the next stage of our research. PMID:24083088

  7. Arthroscopic Posterior Subtalar Arthrodesis: Surgical Technique

    PubMed Central

    Vilá y Rico, Jesús; Ojeda Thies, Cristina; Parra Sanchez, Guillermo

    2016-01-01

    Surgical fusion of the subtalar joint is a procedure indicated to alleviate pain of subtalar origin, such as in post-traumatic osteoarthritis, adult-acquired flatfoot deformity, and other disorders. Open subtalar arthrodesis has been performed with predictable results, but concerns exist regarding injury to proprioception and local vascularity due to wide surgical dissection. Minimally invasive techniques try to improve results by avoiding these issues but have a reputation for being technically demanding. We describe the surgical technique for arthroscopic subtalar arthrodesis, which has proved to be a safe and reliable technique in our experience, with consistent improvements in American Orthopaedic Foot & Ankle Society scores. PMID:27073783

  8. Cochlear implant simulator for surgical technique analysis

    NASA Astrophysics Data System (ADS)

    Turok, Rebecca L.; Labadie, Robert F.; Wanna, George B.; Dawant, Benoit M.; Noble, Jack H.

    2014-03-01

    Cochlear Implant (CI) surgery is a procedure in which an electrode array is inserted into the cochlea. The electrode array is used to stimulate auditory nerve fibers and restore hearing for people with severe to profound hearing loss. The primary goals when placing the electrode array are to fully insert the array into the cochlea while minimizing trauma to the cochlea. Studying the relationship between surgical outcome and various surgical techniques has been difficult since trauma and electrode placement are generally unknown without histology. Our group has created a CI placement simulator that combines an interactive 3D visualization environment with a haptic-feedback-enabled controller. Surgical techniques and patient anatomy can be varied between simulations so that outcomes can be studied under varied conditions. With this system, we envision that through numerous trials we will be able to statistically analyze how outcomes relate to surgical techniques. As a first test of this system, in this work, we have designed an experiment in which we compare the spatial distribution of forces imparted to the cochlea in the array insertion procedure when using two different but commonly used surgical techniques for cochlear access, called round window and cochleostomy access. Our results suggest that CIs implanted using round window access may cause less trauma to deeper intracochlear structures than cochleostomy techniques. This result is of interest because it challenges traditional thinking in the otological community but might offer an explanation for recent anecdotal evidence that suggests that round window access techniques lead to better outcomes.

  9. [Surgical renal biopsies: technique, effectiveness and complications].

    PubMed

    Pinsach Elías, L; Blasco Casares, F J; Ibarz Servió, L; Valero Milián, J; Areal Calama, J; Bucar Terrades, S; Saladié Roig, J M

    1991-01-01

    Retrospective study made on 140 renal surgical biopsies (RSB) performed throughout the past 4 years in our Unit. The technique's effectiveness and morbidity are emphasized and the surgical technique and type of anaesthesia described. The sample obtained was enough to perform an essay in 100% cases, and a diagnosis was reached in 98.5%. Thirty-nine patients (27.8%) presented complications, 13 (9.2%) of which were directly related to the surgical technique. No case required blood transfusion and no deaths were reported. The type of anaesthesia used was: local plus sedation in 104 (74.2%) cases, rachianaesthesia in 10 (7.1%) and general in 26 (18.5%). The same approach was used in all patients: minimal subcostal lumbotomy, using Wilde's forceps to obtain the samples. It is believed that RSB is a highly effective, low mortality procedure, easy and quick to perform, and suitable for selected patients. PMID:1927642

  10. Fertility-preserving surgical procedures, techniques.

    PubMed

    Martinez, Alejandra; Poilblanc, Mathieu; Ferron, Gwenael; De Cuypere, Mariolene; Jouve, Eva; Querleu, Denis

    2012-06-01

    As a result of the trend toward late childbearing, fertility preservation has become a major issue in young women with gynaecological cancer. Fertility-sparing treatments have been successfully attempted in selected cases of cervical, endometrial and ovarian cancer, and gynaecologists should be familiar with fertility-preserving options in women with gynaecological malignancies. Options to preserve fertility include shielding to reduce radiation damage, fertility preservation when undergoing cytotoxic treatments, cryopreservation, assisted reproduction techniques, and fertility-sparing surgical procedures. Radical vaginal trachelectomy with laparoscopic lymphadenectomy is an oncologically safe, fertility-preserving procedure. It has been accepted worldwide as a surgical treatment of small early stage cervical cancers. Selected cases of early stage ovarian cancer can be treated by unilateral salpingo-ophorectomy and surgical staging. Hysteroscopic resection and progesterone treatment are used in young women who have endometrial cancer to maintain fertility and avoid surgical menopause. Appropriate patient selection, and careful oncologic, psychologic, reproductive and obstetric counselling, is mandatory. PMID:22503435

  11. Laparoscopic Surgical Techniques for Endometriosis and Adenomyosis

    PubMed Central

    Wood, C.; Maher, P.; Woods, R.

    2000-01-01

    The details of surgical techniques for laparoscopic removal of endometriosis and adenomyosis are described briefly in textbooks and gynaecological journal articles. We have described a wide variety of techniques for the various procedures required in the treatment of endometriosis and adenomyosis, excluding hysterectomy. The principles are based upon those used in removal of primary cancer lesions. The limitations of thermal ablation are discussed, and evidence of improved results after excision of lesions have been submitted for publication. PMID:18493534

  12. Surgical techniques of orthotopic rat liver transplantation.

    PubMed

    Spiegel, H U; Palmes, D

    1998-01-01

    Liver transplantation in rats is frequently used as a transplantation model. Although liver transplantation in larger laboratory animals such as dogs and pigs is technically easier, the rat has become the most important subject for experimental liver transplantation because of the availability of genetically defined animals. Numerous surgical techniques have been developed that permit the investigator to carry out studies with high clinical relevance. In this article the principal models of orthotopic rat liver transplantation and their technical modifications of vessel anastomoses, rearterialization, and bile duct reconstruction techniques are reviewed. More than 20 transplantation models are described in detail and demonstrated with clear illustrations. Finally, the advantages and uses of all the surgical procedures (e.g., suture and cuff anastomoses, bile duct anastomoses, and rearterialization techniques), specific problems, and survival criteria are discussed and the experiences of investigators who applied these techniques are analyzed. In conclusion, an overview and critical evaluation of all surgical techniques of orthotopic rat liver transplantation are given, together with instructions for learning these techniques. PMID:9700616

  13. [Idiopathic Progressive Subglottic Stenosis: Surgical Techniques].

    PubMed

    Hoetzenecker, K; Schweiger, T; Klepetko, W

    2016-09-01

    Idiopathic subglottic stenosis is a disease characterized by slow, progressive scarring and constriction of the subglottic airway. It almost always occurs in females between the 3rd and 5th decade of life. Symptoms are frequently misinterpreted as asthma and patients are referred for endoscopic evaluation only when asthma medications fail to alleviate their symptoms. Treatment options can be divided into endoscopic and open surgical techniques. Microlaryngoscopic scar reduction by laser followed by balloon dilation usually delivers good short-term results. However, the majority of patients will experience restenosis within a short period of time. Open surgical correction techniques are based on a complete removal of the affected airway segment. This must be combined with various extended resection techniques in patients with advanced stenosis. Depending on the extent and severity of the stenosis the following surgical techniques are required: standard cricotracheal resection (Grillo's technique), cricoplasty with dorsal and lateral mucosaplasty, or a combination of resection and enlargement techniques using rib cartilage grafts. In experienced centres, success rates of over 95 % are reported with good functional outcome of voice and deglutition. PMID:27607884

  14. Surgical discectomy for lumbar disc herniation: surgical techniques.

    PubMed

    Blamoutier, A

    2013-02-01

    Discectomy for lumbar discal herniation is the most commonly performed spinal surgery. The basic principle of the various techniques is to relieve the nerve root compression induced by the herniation. Initially, the approach was a unilateral posterior 5-cm incision: the multifidus was detached from the vertebra, giving access through an interlaminar space in case of posterolateral herniation; an alternative paraspinal approach was used for extraforaminal herniation. Over the past 30 years, many technical improvements have decreased operative trauma by reducing incision size, thereby reducing postoperative pain and hospital stay and time off work, while improving clinical outcome. Magnification and illumination systems by microscope and endoscope have been introduced to enable minimally invasive techniques. Several comparative studies have analyzed the clinical results of these various techniques. Although the methodology of most of these studies is debatable, all approaches seem to provide clinical outcomes of similar quality. At all events, minimally invasive techniques reduce hospital stay. While technical proficiency is essential, the final result depends on strict compliance with a prerequisite for surgical indication: close correlation between clinical symptoms and radiological findings. It is essential to discuss the risk/benefit ratio and explain the pros and cons of the recommended technique to the patient. PMID:23352565

  15. [Continent cecal-colonic reservoir. Surgical technique].

    PubMed

    Del Boca, C; Ferrari, C; Zanoni, V; Dieci, G; Grignani, G C; Musci, R

    1990-09-30

    The Authors discuss a recent case report treated with radial cystectomy associated with a secondary urinary derivation using the caecum-colon reservoir. After having reviewed the various surgical procedures involving the urinary derivations, the Authors describe the technique used by them paying particular attention to the positive aspects of having a low filling pressure reservoir controlled by a valid sphincter ileum-caecum valve. Considering the good postoperative result with this method, the Authors regard this procedure as an alternative to other urinary derivation techniques when carried out with correct indications. PMID:2287469

  16. Surgical implantation techniques for electronic tags in fish

    SciTech Connect

    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.

  17. [Salter innominate osteotomy : Indications, surgical technique, results].

    PubMed

    Schulze, A; Tingart, M

    2016-08-01

    The prevalence of congenital hip dysplasia in Germany is 2-4 % and that of hip dislocation is 0.5-1 %. If early therapy is not successful or the hip dysplasia or dislocation is diagnosed too late (children of over 1 year of age) surgical treatment is indicated to increase the femoral coverage. The innominate osteotomy, published by Robert B. Salter 1961, is a worldwide established technique to improve the lateral and ventral coverage of the femoral head in primary or secondary hip dysplasia or dislocation. In this paper we discuss Salter's technique and present indications, the perioperative procedure, operative modifications and operative extensions and demonstrate the anatomical requirements, postoperative biomechanical changes and long-term results. PMID:27351429

  18. Code Optimization Techniques

    SciTech Connect

    MAGEE,GLEN I.

    2000-08-03

    Computers transfer data in a number of different ways. Whether through a serial port, a parallel port, over a modem, over an ethernet cable, or internally from a hard disk to memory, some data will be lost. To compensate for that loss, numerous error detection and correction algorithms have been developed. One of the most common error correction codes is the Reed-Solomon code, which is a special subset of BCH (Bose-Chaudhuri-Hocquenghem) linear cyclic block codes. In the AURA project, an unmanned aircraft sends the data it collects back to earth so it can be analyzed during flight and possible flight modifications made. To counter possible data corruption during transmission, the data is encoded using a multi-block Reed-Solomon implementation with a possibly shortened final block. In order to maximize the amount of data transmitted, it was necessary to reduce the computation time of a Reed-Solomon encoding to three percent of the processor's time. To achieve such a reduction, many code optimization techniques were employed. This paper outlines the steps taken to reduce the processing time of a Reed-Solomon encoding and the insight into modern optimization techniques gained from the experience.

  19. Surgical techniques in type A dissection

    PubMed Central

    Hussain, Syed T.

    2016-01-01

    Acute aortic dissection is a surgical emergency that must be urgently managed, with the primary goal of restoring flow to the dominant true lumen in the downstream aorta. Our preference at the Cleveland Clinic is for an open distal anastomosis technique without aortic clamping, as it permits more accurate approximation of dissected layers and more homeostatically secure anastomosis. During this procedure we employ right axillary end-to-side graft perfusion, followed by deep hypothermic circulatory arrest and antegrade brain perfusion. The distal anastomosis is performed without felt strips or glue. Critical to achieving a successful outcome is meticulous de-airing of the arch, diligent myocardial protection, and a water-tight anastomosis prior to discontinuing cardiopulmonary bypass. PMID:27386412

  20. [Robot-assisted laparoscopic prostatectomy: surgical technique].

    PubMed

    Rocco, B; Coelho, R F; Albo, G; Patel, V R

    2010-09-01

    Prostate tumours are among the most frequently diagnosed solid tumours in males (a total of 192,280 new cases in the USA in 2009); since the approval of the PSA test by the Food and Drug Administration in 1986, incidence has risen significantly, particularly in the '90s; furthermore the spread of the PSA test has led to an increased frequency of cancer diagnosis at the localised stage. The standard treatment for tumour of the prostate is retropubic radical prostatectomy (RRP) which however is not morbidity-free, e.g. intraoperative bleeding, urinary incontinence and erectile dysfunction. This is why the interest of the scientific community has turned increasingly to mini-invasive surgical procedures able to achieve the same oncological results as the open procedure, but which also reduce the impact of the treatment on these patients' quality of life. The first step in this direction was laparoscopic prostatectomy described by Schuessler in 1992 and standardised by Gaston in 1997. However, the technical difficulty inherent in this procedure has limited its more widespread use. In May 2000 Binder and Kramer published a report on the first robot-assisted prostatectomy (RARP) using the Da Vinci system (da Vinci TM, Intuitive Surgical, Sunnyvale, CA, USA). From the original experience, RARP, which exploits the advantages of an enlarged, three-dimensional view and the ability of the instruments to move with 7 degrees of freedom, the technique has spread enormously all over the world. At the time of writing, in the USA, RARP is the most common therapeutic option for the treatment of prostate tumour at localised stage. In the present study we describe the RARP technique proposed by dr. Vipul Patel, head of the Global Robotic Institute (Orlando Fl). PMID:20940698

  1. [Surgical treatment and localization techniques in primary hyperparathyroidism].

    PubMed

    Marazuela, Mónica; Domínguez-Gadea, Luis; Manuel Bravo-Linfante, José; Larrañaga, Eduardo

    2009-04-01

    Parathyroidectomy is the only definitive cure for primary hyperparathyroidism (PHPT). While bilateral neck exploration has been the conventional surgical approach and the mainstay of therapy, recent advances in technology have revolutionized the field, making a focused or minimally invasive approach to parathyroidectomy a reality. This change has taken place because of the development of accurate preoperative localization techniques able to select patients who have single-gland parathyroid disease (single adenoma) and can be managed by a minimally invasive parathyroidectomy. Currently, the most reliable and practical diagnostic procedure is (99m)TC-sestamibi parathyroid scintigraphy, using different protocols depending on the institution's logistics and experience (classical dual-phase, oblique projections, various subtraction techniques and/or single photon-emission computed tomography or SPECT). Ultrasound has emerged as a complementary technique in the preoperative evaluation of PHPT, which can be used when scintigraphy is negative or as a confirmatory test. When these procedures fail to identify the enlarged gland, other non-invasive procedures such as computed tomographic scanning or magnetic resonance imaging are used in selected cases. A variety of surgical techniques have been employed to achieve a safe and effective minimally invasive procedure. These techniques include mini-incision unilateral parathyroid exploration and endoscopic, video-assisted and radio-guided parathyroidectomy. With optimized preoperative mapping, the success rate of these less invasive techniques equals that of the traditional bilateral approach. This review summarizes the imaging techniques and rationale for preoperative localization studies that are used before parathyroidectomy, as well as the current surgical approaches. PMID:19627757

  2. Sternoclavicular dislocation: case report and surgical technique.

    PubMed

    Terra, Bernardo Barcellos; Rodrigues, Leandro Marano; Pádua, David Victoria Hoffmann; Martins, Marcelo Giovanini; Teixeira, João Carlos de Medeiros; De Nadai, Anderson

    2015-01-01

    Sternoclavicular dislocations account for less than 5% of all dislocations of the scapular belt. Most cases of anterior dislocation of the sternoclavicular joint do not present symptoms. However, some patients may develop chronic anterior instability and remain symptomatic, and surgical treatment is indicated in these cases. There is a scarcity of reports in the literature relating to reconstruction using the long palmar tendon in cases of traumatic anterior instability. Although rare, these injuries deserve rapid diagnosis and efficient treatment in order to avoid future complications. The aim of this report was to report on a case of a motocross competitor who developed chronic traumatic anterior instability of the sternoclavicular joint and underwent surgical reconstruction using the autogenous long palmar tendon. The patient was a 33-year-old man with a history of anterior dislocation of the sternoclavicular subsequent to a fall during a maneuver in a motocross competition. Conservative treatment was instituted initially, consisting of use of a functional sling to treat the symptoms for 3 weeks, along with physiotherapeutic rehabilitation for 3 months. We chose to use a modification of the "figure of eight" technique based on the studies by Spencer and Kuhn. A longitudinal incision of approximately 10 cm was made at the level of the sternoclavicular joint. The graft from the ipsilateral long palmar tendon was passed through the orifices in the form of a modified "figure of eight" and its ends were sutured together. The patient was immobilized using an American sling for 4 weeks. After 6 months of follow-up, the patient no longer presented pain or instability when movement of the sternoclavicular joint was required. Minor discomfort and slight prominence of the sternoclavicular joint continued to be present but did not affect the patient's activities. Thus, the patient was able to return to racing 6 months after the operation. Our study presented a case of

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

    PubMed

    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. PMID:26064759

  4. Evolving Educational Techniques in Surgical Training.

    PubMed

    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". PMID:26612021

  5. [Robot-assisted radical prostatectomy: surgical techniques].

    PubMed

    Kojima, Yoshiyuki; Sato, Yuichi; Ogawa, Soichiro; Haga, Nobuhiro; Yanagida, Tomohiko

    2016-01-01

    Robot-assisted radical prostatectomy (RARP) for the patients with localized prostate cancer is increasingly being adopted around the world. The da Vinci surgical system (Intuitive Surgical, Sunnyvale, CA, USA) provides the advantages of simplification and precision of exposure and suturing because of allowing movements of the robotic arm in real time with increased degree of freedom and magnified 3-dimensional view. Therefore, RARP has been expected to provide superior therapeutic benefit to patients in terms of surgical outcome to open or laparoscopic radical prostatectomy. In this review, we provide our technical aspects and tips and tricks of RARP to improve surgical outcome and postoperative quality of life. PMID:26793888

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

    PubMed Central

    Kyriazanos, Ioannis D.; 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. PMID:26064759

  7. Suprasellar cysts: clinical presentation, surgical indications, and optimal surgical treatment

    PubMed Central

    2011-01-01

    Background To describe the clinical presentation of suprasellar cysts (SSCs) and surgical indications, and compare the treatment methods of endoscopic ventriculocystostomy (VC) and ventriculocystocisternotomy (VCC). Methods We retrospectively reviewed the records of 73 consecutive patients with SSC who were treated between June 2002 and September 2009. Twenty-two patients were treated with VC and 51 with VCC. Outcome was assessed by clinical examination and magnetic resonance imaging. Results The patients were divided into five groups based on age at presentation: age less than 1 year (n = 6), 1-5 years (n = 36), 6-10 years (n = 15), 11-20 years (n = 11), and 21-53 years (n = 5). The main clinical presentations were macrocrania (100%), motor deficits (50%), and gaze disturbance (33.3%) in the age less than 1 year group; macrocrania (75%), motor deficits (63.9%), and gaze disturbance (27.8%) in the 1-5 years group; macrocrania (46.7%), symptoms of raised intracranial pressure (ICP) (40.0%), endocrine dysfunction (40%), and seizures (33.3%) in the 6-10 years group; symptoms of raised ICP (54.5%), endocrine dysfunction (54.5%), and reduced visual field or acuity (36.4%) in the 11-20 years group; and symptoms of raised ICP (80.0%) and reduced visual field or acuity (40.0%) in the 21-53 years group. The overall success rate of endoscopic fenestration was 90.4%. A Kaplan-Meier curve for long-term efficacy of the two treatment modalities showed better results for VCC than for VC (p = 0.008). Conclusions Different age groups with SSCs have different main clinical presentations. VCC appears to be more efficacious than VC. PMID:21586175

  8. OPTIMIZING EXPOSURE MEASUREMENT TECHNIQUES

    EPA Science Inventory

    The research reported in this task description addresses one of a series of interrelated NERL tasks with the common goal of optimizing the predictive power of low cost, reliable exposure measurements for the planned Interagency National Children's Study (NCS). Specifically, we w...

  9. Computer-Assisted Technique for Surgical Tooth Extraction.

    PubMed

    Hamza, Hosamuddin

    2016-01-01

    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. PMID:27127510

  10. Computer-Assisted Technique for Surgical Tooth Extraction

    PubMed Central

    Hamza, Hosamuddin

    2016-01-01

    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. PMID:27127510

  11. Development of the implant surgical technique and assessment rating system

    PubMed Central

    Park, Jung-Chul; Hwang, Ji-Wan; Lee, Jung-Seok; Jung, Ui-Won; Choi, Seong-Ho; Cho, Kyoo-Sung; Chai, Jung-Kiu

    2012-01-01

    Purpose There has been no attempt to establish an objective implant surgical evaluation protocol to assess residents' surgical competence and improve their surgical outcomes. The present study presents a newly developed assessment and rating system and simulation model that can assist the teaching staffs to evaluate the surgical events and surgical skills of residents objectively. Methods Articles published in peer-reviewed English journals were selected using several scientific databases and subsequently reviewed regarding surgical competence and assessment tools. Particularly, medical journals reporting rating and evaluation protocols for various types of medical surgeries were thoroughly analyzed. Based on these studies, an implant surgical technique assessment and rating system (iSTAR) has been developed. Also, a specialized dental typodont was developed for the valid and reliable assessment of surgery. Results The iSTAR consists of two parts including surgical information and task-specific checklists. Specialized simulation model was subsequently produced and can be used in combination with iSTAR. Conclusions The assessment and rating system provided may serve as a reference guide for teaching staffs to evaluate the residents' implant surgical techniques. PMID:22413071

  12. Equine thoracoscopy: normal anatomy and surgical technique.

    PubMed

    Peroni, J F; Horner, N T; Robinson, N E; Stick, J A

    2001-05-01

    Six normal, healthy horses age 3-10 years underwent left and right thoracoscopic examination using a rigid telescope. A minimum of 30 days was allowed between procedures. Horses were restrained in stocks and sedated with a continuous detomidine infusion. After surgical preparation of the hemithorax elected for surgery, and administration of local or regional anaesthesia of the surgery sites, thoracoscopy was completed during two 15 min pneumothorax periods. During the procedures, the thoracic structures were viewed using a 57 cm, 10 mm diameter, 30 degrees rigid telescope connected to a digital camcorder to allow computer capture of digital images. The telescope was inserted into the thoracic cavity via 3 different intercostal spaces. The 8th, 10th and 12th intercostal spaces were randomly selected and used among horses. The exploration of each hemithorax started from the dorsal-caudal quadrant continued toward the cranial thorax and was completed by observing the diaphragmatic and caudal pulmonary region. Collapsed lung, aorta, oesophagus and diaphragm were viewed readily in either hemithorax. On exploration of the right hemithorax, the azygos vein, thoracic duct and pulmonary veins were also identified. Horses tolerated thoracoscopy well. Signs of discomfort, such as increased respiratory rate, coughing and decreased level of sedation, were associated with lung collapse in one horse, with pneumothorax on 2 occasions, and when the thorax was approached through the 8th intercostal space. Surgery performed via the 8th intercostal space was hindered by the rigidity of the 8th and 9th ribs, and by the presence of a greater musculature, which did not allow easy cranial and caudal movements of the telescope. PMID:11352343

  13. Soft Tissue Surgical Procedures for Optimizing Anterior Implant Esthetics

    PubMed Central

    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

  14. Techniques for shuttle trajectory optimization

    NASA Technical Reports Server (NTRS)

    Edge, E. R.; Shieh, C. J.; Powers, W. F.

    1973-01-01

    The application of recently developed function-space Davidon-type techniques to the shuttle ascent trajectory optimization problem is discussed along with an investigation of the recently developed PRAXIS algorithm for parameter optimization. At the outset of this analysis, the major deficiency of the function-space algorithms was their potential storage problems. Since most previous analyses of the methods were with relatively low-dimension problems, no storage problems were encountered. However, in shuttle trajectory optimization, storage is a problem, and this problem was handled efficiently. Topics discussed include: the shuttle ascent model and the development of the particular optimization equations; the function-space algorithms; the operation of the algorithm and typical simulations; variable final-time problem considerations; and a modification of Powell's algorithm.

  15. Three-piece Inflatable Penile Prosthesis: Surgical Techniques and Pitfalls

    PubMed Central

    Al-Enezi, Ahmad; Al-Khadhari, Sulaiman; Al-Shaiji, Tariq F.

    2011-01-01

    Penile prosthesis surgery plays a vital role in the treatment of erectile dysfunction (ED). As far as outcome is concerned, it is one of the most rewarding procedures for both patients and surgeons. We describe our surgical technique for implantation of the three-piece inflatable penile prosthesis and point out the major surgical pitfalls accompanying this procedure and their specific management. The psychological outcome of penile prosthesis surgery is also discussed. Different surgical approaches are available when performing the procedure. A number of procedure-related problems can be encountered and a thorough knowledge of these is of paramount importance. Penile prosthesis surgery has a favorable psychological outcome. Surgery for implantation of an inflatable penile prosthesis is a rewarding procedure, with a high yield of patient satisfaction. Urologists should have thorough understanding of the surgical pitfalls peculiar to this procedure and their management. PMID:22413049

  16. HOSPITALIZATION TIME AFTER OPEN APPENDECTOMY BY THREE DIFFERENT SURGICAL TECHNIQUES

    PubMed Central

    XIMENES, Agláia Moreira Garcia; MELLO, Fernando Salvo Torres; de LIMA-JÚNIOR, Zailton Bezerra; FERREIRA, Cícero Faustino; CAVALCANTI, Amanda Dantas Ferreira; DIAS-FILHO, Adalberto Vieira

    2014-01-01

    Background The choice of surgical technique to approach the appendicular stump depends mostly on skill and personal preference of the surgeon or on the protocol used in the service, and the influence of this choice in hospitalization time is not evaluated. Aim To evaluate the relation between surgical technique and postoperative hospitalization time in patients presenting with acute appendicitis. Methods Retrospective analysis of 180 patients who underwent open appendectomy. These where divided into three groups according to surgical technique: conventional appendectomy (simple ligation of the stump), tobacco pouch suture and Parker-Kerr suture. Data where crossed with hospitalization time (until three days, from four to six days and over seven days). Results A hundred and eighty patients with age from 15 to 85 years where included. From these, 95 underwent conventional technique, had an average hospitalization time of 3,9 days and seven had complications (surgical site infection, seroma, suture dehiscence and evisceration). In 67 patients, tobacco pouch suture was chosen and had average hospitalization time of 3,7 days and two complications (infection and seroma). In 18 Parker-Kerr suture was made, with average hospitalization time of 2,6 days, with no complication. Contingency coefficient between the variables hospitalization time and technique was 0,255 and Cramér's V was 0,186. Conclusion There was tendency to larger hospitalization time and larger number of complications in conventional appendectomy, whereas in patients where Parker-Kerr suture was performed, hospitalization time was significantly smaller. PMID:25184769

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

    PubMed

    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. PMID:27300457

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

    ERIC Educational Resources Information Center

    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)

  19. Surgical techniques for advanced stage pelvic organ prolapse.

    PubMed

    Brown, Douglas N; Strauchon, Christopher; Gonzalez, Hector; Gruber, Daniel

    2016-02-01

    Pelvic organ prolapse is an extremely common condition, with approximately 12% of women requiring surgical correction over their lifetime. This manuscript reviews the most recent literature regarding the comparative efficacy of various surgical repair techniques in the treatment of advanced stage pelvic organ prolapse. Uterosacral ligament suspension has similar anatomic and subjective outcomes when compared to sacrospinous ligament fixation at 12 months and is considered to be equally effective. The use of transvaginal mesh has been shown to be superior to native tissue vaginal repairs with respect to anatomic outcomes but at the cost of a higher complication rate. Minimally invasive sacrocolpopexy appears to be equivalent to abdominal sacrocolpopexy (ASC). Robot-assisted sacrocolpopexy (RSC) and laparoscopic sacrocolpopexy (LSC) appear as effective as abdominal sacrocolpopexy, however, prospective studies of comparing long-term outcomes of ASC, LSC, and RSC in relation to health care costs is paramount in the near future. Surgical correction of advanced pelvic organ prolapse can be accomplished via a variety of proven techniques. Selection of the correct surgical approach is a complex decision process and involves a multitude of factors. When deciding on the most suitable surgical intervention, the chosen route must be individualized for each patient taking into account the specific risks and benefits of each procedure. PMID:26448444

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

    PubMed

    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. PMID:26346781

  1. Epilepsy Surgery for Pediatric Epilepsy: Optimal Timing of Surgical Intervention

    PubMed Central

    SUGANO, Hidenori; ARAI, Hajime

    2015-01-01

    Pediatric epilepsy has a wide variety of etiology and severity. A recent epidemiological study suggested that surgery might be indicated in as many as 5% of the pediatric epilepsy population. Now, we know that effective epilepsy surgery can result in seizure freedom and improvement of psychomotor development. Seizure control is the most effective way to improve patients neurologically and psychologically. In this review, we look over the recent evidence related to pediatric epilepsy surgery, and try to establish the optimal surgical timing for patients with intractable epilepsy. Appropriate surgical timing depends on the etiology and natural history of the epilepsy to be treated. The most common etiology of pediatric intractable epilepsy patients is malformation of cortical development (MCD) and early surgery is recommended for them. Patients operated on earlier than 12 months of age tended to improve their psychomotor development compared to those operated on later. Recent progress in neuroimaging and electrophysiological studies provide the possibility of very early diagnosis and comprehensive surgical management even at an age before 12 months. Epilepsy surgery is the only solution for patients with MCD or other congenital diseases associated with intractable epilepsy, therefore physicians should aim at an early and precise diagnosis and predicting the future damage, consider a surgical solution within an optimal timing. PMID:25925754

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

    NASA Astrophysics Data System (ADS)

    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.

  3. Halstedian technique revisited. Innovations in teaching surgical skills.

    PubMed Central

    Barnes, R W; Lang, N P; Whiteside, M F

    1989-01-01

    This paper reviews the laboratory models used to teach fundamental surgical skills in our general surgery residency. The laboratory modules allow supervision and self-instruction, practice, and videotape monitoring of the following techniques: skin incision, suturing, knot tying, hemostasis, vascular anastomosis, and intestinal anastomosis. Pigs' feet simulate human skin for exercises in skin incision, lesion excision, suturing, and basic plastic surgical techniques. Latex tubing and penrose drains allow experience in suturing, knot tying, and hemostasis. Polytetrafluoroethylene vascular prostheses permit quantification of the precision of needle passage and suturing by measurement of leakage of water through a vascular anastomosis. Reconstituted, lyophilized, irradiated bovine arteries and ileum provide models of biologic tissue for creating handsewn vascular anastomoses and sutured or stapled gastrointestinal anastomoses. A headlamp videocamera allows unobstructive recording of the resident's technical performance and provides subsequent visual feedback for self-improvement when compared to reference instructional videotapes. We feel that these innovations may enhance surgical dexterity of residents without the need for animal sacrifice. Our goal is to foreshorten the learning curve for basic surgical skills and improve performance in the clinical operating room. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:2742408

  4. A minimally invasive surgical technique to treat distal clavicle fractures.

    PubMed

    Swanson, Kyle E; Swanson, Britta L

    2009-07-01

    Treatment of distal clavicle fractures ranges from nonoperative to operative approaches. Various surgical procedures have been described in the literature, each with potential complications. For fractures treated operatively, the goal is to maximize stability and functionality while minimizing pain and deformity. This article describes a double-button suture system using a mini-open technique to repair a distal clavicle fracture providing stable fixation with minimal disruption of the surrounding anatomy. PMID:19634845

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

    PubMed

    Crawshaw, Alison; Williams, Julia; Woodhouse, Fran

    2014-09-24

    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. PMID:25251313

  6. AUDIOVISUAL RESOURCES ON THE TEACHING PROCESS IN SURGICAL TECHNIQUE

    PubMed Central

    PUPULIM, Guilherme Luiz Lenzi; IORIS, Rafael Augusto; GAMA, Ricardo Ribeiro; RIBAS, Carmen Australia Paredes Marcondes; MALAFAIA, Osvaldo; GAMA, Mirnaluci

    2015-01-01

    Background: The development of didactic means to create opportunities to permit complete and repetitive viewing of surgical procedures is of great importance nowadays due to the increasing difficulty of doing in vivo training. Thus, audiovisual resources favor the maximization of living resources used in education, and minimize problems arising only with verbalism. Aim: To evaluate the use of digital video as a pedagogical strategy in surgical technique teaching in medical education. Methods: Cross-sectional study with 48 students of the third year of medicine, when studying in the surgical technique discipline. They were divided into two groups with 12 in pairs, both subject to the conventional method of teaching, and one of them also exposed to alternative method (video) showing the technical details. All students did phlebotomy in the experimental laboratory, with evaluation and assistance of the teacher/monitor while running. Finally, they answered a self-administered questionnaire related to teaching method when performing the operation. Results: Most of those who did not watch the video took longer time to execute the procedure, did more questions and needed more faculty assistance. The total exposed to video followed the chronology of implementation and approved the new method; 95.83% felt able to repeat the procedure by themselves, and 62.5% of those students that only had the conventional method reported having regular capacity of technique assimilation. In both groups mentioned having regular difficulty, but those who have not seen the video had more difficulty in performing the technique. Conclusion: The traditional method of teaching associated with the video favored the ability to understand and transmitted safety, particularly because it is activity that requires technical skill. The technique with video visualization motivated and arouse interest, facilitated the understanding and memorization of the steps for procedure implementation, benefiting the

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

    PubMed

    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. PMID:27423673

  8. The anatomic coracoclavicular ligament reconstruction: surgical technique and indications.

    PubMed

    Carofino, Brad C; Mazzocca, Augustus D

    2010-03-01

    The anatomic coracoclavicular ligament reconstruction (ACCR) is a surgical procedure to address acriomioclavicular joint instability. The coracoclavicular ligaments are reconstructed using a semitendinosus allograft passed beneath the coracoid and through bone tunnels in the clavicle. The graft is secured with interference screw fixation, and the acromioclavicular joint is retained. Here we describe the authors' surgical technique, indications, and rehabilitation protocol. Also, a preliminary case series of seventeen patients is presented. Patients demonstrated significant improvement in pain levels and function. The mean ASES score increased from 52 preoperatively to 92. The Constant Murley rose from 66.6 to 94.7. There were three failures in this series, and two required revision surgery. PMID:20188267

  9. Male-to-female vaginoplasty: Preecha's surgical technique.

    PubMed

    Wangjiraniran, Burin; Selvaggi, Gennaro; Chokrungvaranont, Prayuth; Jindarak, Sirachai; Khobunsongserm, Sutin; Tiewtranon, Preecha

    2015-06-01

    The inverted peno-scrotal flap is considered the standard technique for vaginoplasty in male-to-female transsexuals. Nowadays, great importance is also given by patients to the reconstruction of the clitoro-labial complex; this is also reconstructed with tissue coming from glans penis, penile skin envelop and scrotal skin. Since the first sex reassignment surgery for biological males performed in Thailand in 1975, Dr Preecha and his team developed the surgical technique for vaginoplasty; many refinements have been introduced during the past 40 years, with nearly 3000 patients operated on. The scope of this paper is to present the surgical technique currently in use for vaginoplasty and clitoro-labioplasty and the refinements introduced at the Chulalongkorn University and at the Preecha Aesthetic Institute, Bangkok, Thailand. These refinements consist of cavity dissection with blunt technique, the use of skin graft in addition to the penile flap, shaping of the clitoris complex from penis glans and clitoral hood, and the use of the urethral mucosa to line the anterior fourchette of the neo-vagina. With the refinements introduced, it has been possible to achieve a result that is very close to the biological female genitalia. PMID:25356769

  10. Bariatric surgery: three surgical techniques, patient care, risks, and outcomes.

    PubMed

    McGraw, Carrie A; Wool, Daniel B

    2015-08-01

    The prevalence of obesity in the United States is a serious health concern. Bariatric surgery is a recognized and accepted approach for addressing weight loss and health conditions that occur as a result of morbid or severe obesity. Lifestyle changes, dietary modifications, and regular exercise are required for optimal and lasting surgical weight loss. Perioperative care of bariatric patients requires the use of interventions that differ from those used for nonobese patients, including bariatric-specific equipment, intraoperative monitoring of blood glucose, and postoperative monitoring for respiratory compromise. This articles outlines the risks and typical outcomes associated with three common bariatric procedures-laparoscopic adjustable gastric banding, laparoscopic sleeve gastrectomy, Roux-en-Y gastric bypass-to help perioperative nurses and other health care providers successfully advise patients and monitor their care for optimal outcomes. PMID:26227518

  11. Surgical repair of complete atrioventricular defect (Nunn technique).

    PubMed

    El-Rassi, Issam; Charafeddine, Fatimah; Tabbakh, Anas; Aboutaka, Mohammad; Khater, Daniele; Arabi, Mariam; Bitar, Fadi

    2015-01-01

    Two procedures have been traditionally used for the surgical repair of complete atrioventricular canal. The single-patch technique includes the division of valve leaflets, and the use of one patch to close the ventricular and the atrial septal defects, whereas the double-patch technique uses two separate patches, without the division of the bridging leaflets. Between 1997 and 2007, another technique emerged, the modified single-patch technique, or the 'Australian' technique, whereby the ventricular septal defect (VSD) is closed by the direct apposition of the bridging leaflets against the crest of the defect. Because of the absence of the ventricular septal patch, concerns have been raised about the possible left ventricular outflow tract obstruction (LVOTO), or atrioventricular valve (AVV) distortion, especially in case of a deep VSD, or if the defect extends superiorly. The results of the modified single-patch technique in terms of mortality, immediate and long-term AVV function and LVOTO have been similar to the standard techniques in most reports. This article will describe in detail the operative technique and review the relevant literature. PMID:26443542

  12. Deep Anterior Lamellar Keratoplasty: Indications, Surgical Techniques and Complications

    PubMed Central

    Karimian, Farid; Feizi, Sepehr

    2010-01-01

    The concept of lamellar keratoplasty (LK) is not new. However, it had been abandoned and largely replaced by the time-honored technique of penetrating keratoplasty (PK) because LK is technically demanding, time consuming and gives suboptimal visual outcomes due to interface irregularity arising from manual lamellar dissection. Recent improvements in surgical instruments and introduction of new techniques of maximum depth of corneal dissection as well as inherent advantages such as preservation of globe integrity and elimination of endothelial graft rejection have resulted in a re-introduction of LK as an acceptable alternative to conventional PK. This review article describes the indications, different techniques, clinical outcomes and complications of deep anterior LK. PMID:20543934

  13. Arthroscopic Surgical Techniques for the Management of Proximal Biceps Injuries.

    PubMed

    Werner, Brian C; Holzgrefe, Russell E; Brockmeier, Stephen F

    2016-01-01

    Current arthroscopic surgical techniques for the management of proximal biceps tendon disorders encompass 3 commonly advocated procedures: proximal biceps anchor reattachment (superior labrum anterior to posterior or SLAP repair), biceps tenotomy, and arthroscopic biceps tenodesis. The indications for each procedure vary based on injury pattern, symptomatic presentation, concomitant pathologic abnormality, and most notably, patient factors, such as age, functional demand, and specific sport or activity participation. Outcomes after SLAP repair are generally favorable, although recent studies have found biceps tenodesis to be the preferred treatment for certain patient populations. PMID:26614472

  14. "Security loop" tie: a new technique to overcome loosening of surgical knots.

    PubMed

    Alzacko, Saadallah Mohammad; Majid, Omer Waleed

    2007-11-01

    Sutures require knots so as to ensure optimal tissue closure strength. Loosening of surgical knots during or after tying can lead to an ineffective suture and compromise the final result. Loosening is affected mainly by the type of suture material and nature of surgical field. In palatal surgery, tying secure knots is a major consideration and may present a technical challenge. In this article, and after a review of the literature, we present a new modification of the usual knot-tying technique to maximize knot security and prevent knot loosening after the first throw is done. This technique was found to be effective, simple, fast, easy to learn, and saves time and material. PMID:17964468

  15. Minimally invasive surgical techniques in the management of differentiated thyroid cancer

    PubMed Central

    Tucker, N.; Mitchem, J.; Gillanders, W.

    2015-01-01

    Thyroid cancer is the fifth most common cancer in women with approximately 60,220 expected new cases in the United States in 2013, and the incidence continues to increase each year. Fortunately, the majority are well-differentiated thyroid cancers with excellent overall prognosis. Controversy persists regarding the optimal surgical management of differentiated thyroid cancer in terms of the extent of thyroid resection (thyroid lobectomy vs total thyroidectomy) and the utility of prophylactic central neck dissection (pCND) in low-risk PTC, and papillary thyroid microcarcinoma (PTMC, defined as <10 mm). Thyroid surgical approaches have progressed from the Kocher open incision to minimally invasive techniques that include endoscopic and robotic thyroidectomy. Overall, these minimally invasive techniques have been shown to be safe, and appear to be associated with improved cosmesis and decreased pain compared to open thyroidectomy. PMID:26504264

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

    PubMed Central

    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

  17. Role of Recipient-site Preparation Techniques and Post-operative Wound Dressing in the Surgical Management of Vitiligo

    PubMed Central

    Al-Hadidi, Nour; Griffith, James L; Al-Jamal, Mohammed S; Hamzavi, Iltefat

    2015-01-01

    Vitiligo is an acquired skin disorder characterized by the destruction of melanocytes resulting in achromic macules and patches involving the affected skin. Multiple methods of treatments have emerged to manage vitiligo, including medical and surgical techniques. Among the surgical techniques described in the management of vitiligo are minipunch grafting, split-thickness skin grafting, hair follicle transplantation, suction blister grafting, and cultured and non-cultured autologous melanocyte transplantation. However, prior to grafting optimal recipient-site preparation is needed for graft survival and successful repigmentation outcomes. Similarly, post-operative care of the recipient site is vital to yielding a viable graft irrespective of the transplantation technique employed. This article reviews the multiple methods employed to prepare the recipient site in vitiligo surgeries and the post-surgical conditions which optimize graft viability. A pubmed search was conducted utilizing the key words listed below. PMID:26157306

  18. Role of Recipient-site Preparation Techniques and Post-operative Wound Dressing in the Surgical Management of Vitiligo.

    PubMed

    Al-Hadidi, Nour; Griffith, James L; Al-Jamal, Mohammed S; Hamzavi, Iltefat

    2015-01-01

    Vitiligo is an acquired skin disorder characterized by the destruction of melanocytes resulting in achromic macules and patches involving the affected skin. Multiple methods of treatments have emerged to manage vitiligo, including medical and surgical techniques. Among the surgical techniques described in the management of vitiligo are minipunch grafting, split-thickness skin grafting, hair follicle transplantation, suction blister grafting, and cultured and non-cultured autologous melanocyte transplantation. However, prior to grafting optimal recipient-site preparation is needed for graft survival and successful repigmentation outcomes. Similarly, post-operative care of the recipient site is vital to yielding a viable graft irrespective of the transplantation technique employed. This article reviews the multiple methods employed to prepare the recipient site in vitiligo surgeries and the post-surgical conditions which optimize graft viability. A pubmed search was conducted utilizing the key words listed below. PMID:26157306

  19. Tactical and surgical techniques issues in the surgical treatment of incisional hernias

    PubMed Central

    Gangură, AG; Palade, RŞ

    2014-01-01

    Abstract Within five years, between 2006 and 2011, a total of 368 incisional hernias have been operated in the Surgery Clinic 1, University Emergency Hospital Bucharest. The study followed the morphological and biological parameters, associated pathology, tactics and surgical technique used and postoperative morbidity. The average age of patients was 61.75 years, female sex was predominant (81.25%), and incisional hernias were large and giant in a percentage of 73.37%. Locations were predominantly median (83.42%). Recurrent incisional hernias and multiple relapsed hernias represented 25.54%. Associated pathology was dominated by obesity (51,09%) and cardiovascular disease (37,77%). We have used both methods of tissue procedures (22.83%), and the prosthetic procedures (77.17%). Prosthetic techniques, retro muscle fitting mesh in the rectus abdominis muscle sheath (Rives-Stoppa technique), fitting ov er the fascia and tissue replacement techniques were performed. Immediate postoperative morbidity was represented by seroma (14.13%), prolonged postoperative ileus (8.69%), prolonged hematic drainage (6.52%), and hematoma (1.9%). Late postoperative morbidity was given by granulomas (5.7%) and recurrence of incisional hernias (4.34%). Good and very good results were obtained in the 89.96% of the operated cases. PMID:25408770

  20. Effect of Surgical Technique on Corneal Implant Performance

    PubMed Central

    Ljunggren, Monika Kozak; Elizondo, Rodolfo A.; Edin, Joel; Olsen, David; Merrett, Kimberley; Lee, Chyan-Jang; Salerud, Göran; Polarek, James; Fagerholm, Per; Griffith, May

    2014-01-01

    Purpose Our aim was to determine the effect of a surgical technique on biomaterial implant performance, specifically graft retention. Methods Twelve mini pigs were implanted with cell-free, 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) cross-linked recombinant human collagen type III (RHCIII) hydrogels as substitutes for donor corneal allografts using overlying sutures with or without human amniotic membrane (HAM) versus interrupted sutures with HAM. The effects of the retention method were compared as well as the effects of collagen concentration (13.7% to 15% RHCIII). Results All implanted corneas showed initial haze that cleared with time, resulting in corneas with optical clarity matching those of untreated controls. Biochemical analysis showed that by 12 months post operation, the initial RHCIII implants had been completely remodeled, as type I collagen, was the major collagenous protein detected, whereas no RHCIII could be detected. Histological analysis showed all implanted corneas exhibited regeneration of epithelial and stromal layers as well as nerves, along with touch sensitivity and tear production. Most neovascularization was seen in corneas stabilized by interrupted sutures. Conclusions This showed that the surgical technique used does have a significant effect on the overall performance of corneal implants, overlying sutures caused less vascularization than interrupted sutures. Translational Relevance Understanding the significance of the suturing technique can aid the selection of the most appropriate procedure when implanting artificial corneal substitutes. The same degree of regeneration, despite a higher collagen content indicates that future material development can progress toward stronger, more resistant implants. PMID:24749003

  1. [Osteosynthesis of the clavicle. Indications, surgical technique, results].

    PubMed

    Lindenmaier, H L; Kuner, E H; Becker, B

    1991-05-01

    The osteosynthesis of the clavicle should be the exception and should only be indicated in the case of complicated fractures. The high rate of pseudoarthrosis given in medical literature, is due to errors in indication, selection of implants and in surgical techniques. Procedures like intramedullar wiring, axial screwing and single cerclage-wire suture are unsuited for osteosynthesis of the clavicle. After osteosynthesis of the clavicle we have found exceptional positive results, with respect to functional, radiological and after subjective evaluation, at a low rate of complication without any consequences occurring in the years to come. These results show, that mainly good or even excellent success can be achieved, at a limited indication, combined with careful surgery and a standardized surgery procedure of osteosynthesis of the clavicle. PMID:1874044

  2. Superciliary Keyhole Approach for Unruptured Anterior Circulation Aneurysms: Surgical Technique, Indications, and Contraindications

    PubMed Central

    2014-01-01

    Neurosurgeons have been trying to reduce surgical invasiveness by applying minimally invasive keyhole approaches. Therefore, this paper clarifies the detailed surgical technique, its limitations, proper indications, and contraindications for a superciliary keyhole approach as a minimally invasive modification of a pterional approach. Successful superciliary keyhole surgery for unruptured aneurysms requires an understanding of the limitations and the use of special surgical techniques. Essentially, this means the effective selection of surgical indications, usage of the appropriate surgical instruments with a tubular shaft, and refined surgical techniques, including straightforward access to the aneurysm, clean surgical dissection, and the application of clips with an appropriate configuration. A superciliary keyhole approach allows unruptured anterior circulation aneurysms to be clipped safely, rapidly, and less invasively on the basis of appropriate surgical indications. PMID:25535512

  3. Optimal multiobjective design of digital filters using spiral optimization technique.

    PubMed

    Ouadi, Abderrahmane; Bentarzi, Hamid; Recioui, Abdelmadjid

    2013-01-01

    The multiobjective design of digital filters using spiral optimization technique is considered in this paper. This new optimization tool is a metaheuristic technique inspired by the dynamics of spirals. It is characterized by its robustness, immunity to local optima trapping, relative fast convergence and ease of implementation. The objectives of filter design include matching some desired frequency response while having minimum linear phase; hence, reducing the time response. The results demonstrate that the proposed problem solving approach blended with the use of the spiral optimization technique produced filters which fulfill the desired characteristics and are of practical use. PMID:24083108

  4. Traumatic laryngotracheal stenosis--an alternative surgical technique.

    PubMed

    Syal, Rajan; Tyagi, Isha; Goyal, Amit

    2006-02-01

    Reconstruction of combined laryngotracheal stenosis requires complex techniques including resection and incorporation of grafts and stents that can be performed as single or multistaged procedure. A complicated case of traumatic laryngotracheal stenosis was managed by us, surgical technique is discussed. A 16-year-old male presented with Stage-3 laryngotracheal stenosis of grade-3 to 4 (>70% of the complete obstruction of tracheal lumen) of 5 cm segment of the larynx and trachea. Restoration of the critical functions of respiration and phonation was achieved in this patient by resection anastomosis of the trachea and with subglottic remodeling. Resection of 5 cm long segment of trachea and primary anastomosis in this case would have created tension at the site of anastomosis. So we did tracheal resection of 3 cm segment of trachea along with subglottic remodeling instead of removing the 5 cm segment of stenosed laryngotracheal region and doing thyrotracheal anastomosis. In complicated long segment, laryngotracheal stenosis, tracheal resection and subglottic remodeling with primary anastomosis can be an alternative approach. Fibrin glue can be used to support free bone/cartilage grafts in laryngotracheal reconstructions. PMID:16102847

  5. Perineal Urethrostomy: Surgical and Functional Evaluation of Two Techniques

    PubMed Central

    Decaestecker, Karel; Spinoit, Anne-Francoise; Hoebeke, Piet; Oosterlinck, Willem

    2015-01-01

    Introduction. PU is an option to manage complex and/or recurrent urethral strictures and is necessary after urethrectomy and/or penectomy. PU is generally assumed to be the last option before abandoning the urethral outlet. Methods. Between 2001 and 2013, 51 patients underwent PU. Mean age (± standard deviation) was 60 ± 15 years. Only 13 patients (25.5%) did not undergo previous urethral interventions. PU was performed according to the Johanson (n = 35) or Blandy (n = 16) technique and these 2 groups were compared for surgical failure, maximum urinary flow (Qmax), urinary symptoms, and quality of life (according to the International Prostate Symptom Score). Results. Both groups were similar for patient's and stricture characteristics. Only follow-up duration was significantly longer after Johanson PU (47.9 months versus 11.1 months; P = 0.003). For the entire cohort, 11 patients (21.6%) were considered a failure (9 or 25.7% for Johanson group and 2 or 12.5% for Blandy group; P = 0.248). There was a significant improvement of Qmax in both groups. Quality of life after PU was comparable in both groups. Conclusions. PU is associated with a 21.6% recurrence rate and the patient should be informed about this risk. PMID:25789316

  6. LESS living donor nephrectomy: Surgical technique and results

    PubMed Central

    Alessimi, Abdullah; Adam, Emilie; Haber, Georges-Pascal; Badet, Lionel; Codas, Ricardo; Fehri, Hakim Fassi; Martin, Xavier; Crouzet, Sébastien

    2015-01-01

    Purpose: We present the findings of 50 patients undergoing pure trans-umbilical laparo-endoscopic single-site surgery (LESS) living donor nephrectomy (LDN), between February 2010 and May 2014. Materials and Methods: Laparo-endoscopic single-site surgery LDN was performed through an umbilical incision. Different trocars were used, namely Gelpoint (Applied Mιdical, Rancho Santa Margarita, CA) SILS port (Covidien, Hamilton, Bermuda), R-port (Olympus Surgical, Orangeburg, NY) and standard trocars, inserted through the same skin incision but using separate fascial punctures. The standard laparoscopic technique was employed. The kidney was pre-entrapped in a retrieval bag and extracted trans-umbilically. Data were collected prospectively including questionnaires containing patient reported oral pain medication duration and time to recovery. Results: LESS LDN was successful in all patients. Mean warm ischemia time was 6.2 min (3–15), mean procedure time was 233.2 min (172–300), and hospitalization stay was 3.94 days (3–7) with a visual analogue pain score at discharge of 1.32 (0–3). No intraoperative complications occurred. The mean time of oral pain medication was 8.72 days (1–20) and final scar length was 4.06 cm (3–5). Each allograft was functional. Conclusion: Although challenging, trans-umbilical LESS LDN seems to be feasible and safe. Hence, LESS has the potential to improve cosmetic results and decrease morbidity. PMID:26229326

  7. Bernese periacetabular osteotomy for hip dysplasia: Surgical technique and indications

    PubMed Central

    Kamath, Atul F

    2016-01-01

    For young, active patients with healthy hip cartilage, pelvic osteotomy is a surgical option in to address hip pain and to improve mechanical loading conditions related to dysplasia. Hip dysplasia may lead to arthrosis at an early age due to poor coverage of the femoral head and abnormal loading of the joint articulation. In patients with symptomatic dysplasia and closed triradiate cartilage (generally over age 10), including adolescents and young adults (generally up to around age 40), the Bernese periacetabular osteotomy (PAO) is a durable technique for addressing underlying structural deformity. The PAO involves a modified Smith-Petersen approach. Advantages of the Bernese osteotomy include preservation of the weight-bearing posterior column of the hemi-pelvis, preservation of the acetabular blood supply, maintenance of the hip abductor musculature, and the ability to effect powerful deformity correction about an ideal center of rotation. There is an increasing body of evidence that preservation of the native hip can be improved through pelvic osteotomy. In contrast to hip osteotomy and joint preservation, the role of total hip arthroplasty in young, active patients with correctable hip deformity remains controversial. Moreover, the durability of hip replacement in young patients is inherently limited. Pelvic osteotomy should be considered the preferred method to address correctable structural deformity of the hip in the young, active patient with developmental dysplasia. The Bernese PAO is technically demanding, yet offers reproducible results with good long-term survivorship in carefully selected patients with preserved cartilage and the ability to meet the demands of rehabilitation. PMID:27190755

  8. Bernese periacetabular osteotomy for hip dysplasia: Surgical technique and indications.

    PubMed

    Kamath, Atul F

    2016-05-18

    For young, active patients with healthy hip cartilage, pelvic osteotomy is a surgical option in to address hip pain and to improve mechanical loading conditions related to dysplasia. Hip dysplasia may lead to arthrosis at an early age due to poor coverage of the femoral head and abnormal loading of the joint articulation. In patients with symptomatic dysplasia and closed triradiate cartilage (generally over age 10), including adolescents and young adults (generally up to around age 40), the Bernese periacetabular osteotomy (PAO) is a durable technique for addressing underlying structural deformity. The PAO involves a modified Smith-Petersen approach. Advantages of the Bernese osteotomy include preservation of the weight-bearing posterior column of the hemi-pelvis, preservation of the acetabular blood supply, maintenance of the hip abductor musculature, and the ability to effect powerful deformity correction about an ideal center of rotation. There is an increasing body of evidence that preservation of the native hip can be improved through pelvic osteotomy. In contrast to hip osteotomy and joint preservation, the role of total hip arthroplasty in young, active patients with correctable hip deformity remains controversial. Moreover, the durability of hip replacement in young patients is inherently limited. Pelvic osteotomy should be considered the preferred method to address correctable structural deformity of the hip in the young, active patient with developmental dysplasia. The Bernese PAO is technically demanding, yet offers reproducible results with good long-term survivorship in carefully selected patients with preserved cartilage and the ability to meet the demands of rehabilitation. PMID:27190755

  9. Periodontal plastic surgical technique for gingival fenestration closure.

    PubMed

    Peacock, M E; Mott, D A; Cuenin, M F; Hokett, S D; Fowler, E B

    2001-01-01

    Gingival fenestration is an opening through oral keratinized tissue, usually unattached, that is observed in thin gingiva with usually thick subgingival calculus deposits. This lesion is seen infrequently but may be more common than has been reported; lack of symptoms may inhibit patient awareness. Because surgical correction usually is not required, there are very few reports in the literature concerning this lesion. The following report describes a case of gingival fenestration and surgical treatment with a connective tissue/periosteal graft. PMID:12016683

  10. Multidisciplinary design optimization using multiobjective formulation techniques

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Aditi; Pagaldipti, Narayanan S.

    1995-01-01

    This report addresses the development of a multidisciplinary optimization procedure using an efficient semi-analytical sensitivity analysis technique and multilevel decomposition for the design of aerospace vehicles. A semi-analytical sensitivity analysis procedure is developed for calculating computational grid sensitivities and aerodynamic design sensitivities. Accuracy and efficiency of the sensitivity analysis procedure is established through comparison of the results with those obtained using a finite difference technique. The developed sensitivity analysis technique are then used within a multidisciplinary optimization procedure for designing aerospace vehicles. The optimization problem, with the integration of aerodynamics and structures, is decomposed into two levels. Optimization is performed for improved aerodynamic performance at the first level and improved structural performance at the second level. Aerodynamic analysis is performed by solving the three-dimensional parabolized Navier Stokes equations. A nonlinear programming technique and an approximate analysis procedure are used for optimization. The proceduredeveloped is applied to design the wing of a high speed aircraft. Results obtained show significant improvements in the aircraft aerodynamic and structural performance when compared to a reference or baseline configuration. The use of the semi-analytical sensitivity technique provides significant computational savings.

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

    PubMed Central

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

    2014-01-01

    OBJECTIVES 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. METHODS 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. RESULTS 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

  12. Digital imaging of surgical specimens using a wet scanning technique

    PubMed Central

    Matthews, T; Denney, P

    2001-01-01

    Aim—To develop a simple method of recording digital images of surgical specimens on to a personal computer (PC) for use in presentations for teaching and reporting of their pathology. Methods—A perspex box was constructed to international A4 size 100 mm deep. This box had a base of 3 mm clear perspex with sides and top of 5 mm white perspex. This box was partially filled with distilled water and a specimen immersed in it. It was then placed on top of a standard A4 scanner. The specimen was then scanned into a PC using image capture software. Results—The images produced showed noticeable improvement over normal photographs, especially with specimens prone to wet highlights. Conclusions—The method has proved to be a rapid and efficient means of producing macroscopic images of surgical specimens. Key Words: scanning • personal computer • macroscopic images • surgical specimens PMID:11304853

  13. A technique for optimizing grid blocks

    NASA Technical Reports Server (NTRS)

    Dannenhoffer, John F., III

    1995-01-01

    A new technique for automatically combining grid blocks of a given block-structured grid into logically-rectangular clusters which are 'optimal' is presented. This technique uses the simulated annealing optimization method to reorganize the blocks into an optimum configuration, that is, one which minimizes a user-defined objective function such as the number of clusters or the differential in the sizes of all the clusters. The clusters which result from applying the technique to two different two-dimensional configurations are presented for a variety of objective function definitions. In all cases, the automatically-generated clusters are significantly better than the original clusters. While this new technique can be applied to block-structured grids generated from any source, it is particularly useful for operating on block-structured grids containing many blocks, such as those produced by the emerging automatic block-structured grid generators.

  14. An original technique for surgical stabilisation of traumatic flail chest.

    PubMed Central

    Beltrami, V; Martinelli, G; Giansante, P; Gentile, K

    1978-01-01

    The treatment of chest wall injuries with severe paradoxical movement remains controversial. Intermittent positive-pressure respiration may be appropriate, but in some, especially those requiring exploratory thoracotomy for a visceral lesion, surgical fixation is desirable. We present a simple method using two or three stainless Kirschner wires placed in the chest wall. Results in five cases have been good. Images PMID:694812

  15. Multiobjective optimization techniques for structural design

    NASA Technical Reports Server (NTRS)

    Rao, S. S.

    1984-01-01

    The multiobjective programming techniques are important in the design of complex structural systems whose quality depends generally on a number of different and often conflicting objective functions which cannot be combined into a single design objective. The applicability of multiobjective optimization techniques is studied with reference to simple design problems. Specifically, the parameter optimization of a cantilever beam with a tip mass and a three-degree-of-freedom vabration isolation system and the trajectory optimization of a cantilever beam are considered. The solutions of these multicriteria design problems are attempted by using global criterion, utility function, game theory, goal programming, goal attainment, bounded objective function, and lexicographic methods. It has been observed that the game theory approach required the maximum computational effort, but it yielded better optimum solutions with proper balance of the various objective functions in all the cases.

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

    PubMed Central

    2014-01-01

    Background 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. Methods/Design 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

  17. Surgical techniques for the management of male infertility

    PubMed Central

    Lopushnyan, Natalya A; Walsh, Thomas J

    2012-01-01

    Evaluation and surgical treatment of male infertility has evolved and expanded, now leading to more precise diagnoses and tailored treatments with diminished morbidity and greater success. Surgeries for male infertility are divided into four major categories: (i) diagnostic surgery; (ii) surgery to improve sperm production; (iii) surgery to improve sperm delivery; and (iv) surgery to retrieve sperm for use with in vitro fertilization and intracytoplasmic sperm injection (IVF–ICSI). While today we are more successful than ever in treating male infertility, pregnancy is still not always achieved likely due to factors that remain poorly understood. Clinicians treating infertility should advocate for couple-based therapy, and require that both partners have a thorough evaluation and an informed discussion before undergoing specific surgical therapies. PMID:22120932

  18. Optimization techniques for integrating spatial data

    USGS Publications Warehouse

    Herzfeld, U.C.; Merriam, D.F.

    1995-01-01

    Two optimization techniques ta predict a spatial variable from any number of related spatial variables are presented. The applicability of the two different methods for petroleum-resource assessment is tested in a mature oil province of the Midcontinent (USA). The information on petroleum productivity, usually not directly accessible, is related indirectly to geological, geophysical, petrographical, and other observable data. This paper presents two approaches based on construction of a multivariate spatial model from the available data to determine a relationship for prediction. In the first approach, the variables are combined into a spatial model by an algebraic map-comparison/integration technique. Optimal weights for the map comparison function are determined by the Nelder-Mead downhill simplex algorithm in multidimensions. Geologic knowledge is necessary to provide a first guess of weights to start the automatization, because the solution is not unique. In the second approach, active set optimization for linear prediction of the target under positivity constraints is applied. Here, the procedure seems to select one variable from each data type (structure, isopachous, and petrophysical) eliminating data redundancy. Automating the determination of optimum combinations of different variables by applying optimization techniques is a valuable extension of the algebraic map-comparison/integration approach to analyzing spatial data. Because of the capability of handling multivariate data sets and partial retention of geographical information, the approaches can be useful in mineral-resource exploration. ?? 1995 International Association for Mathematical Geology.

  19. Software for the grouped optimal aggregation technique

    NASA Technical Reports Server (NTRS)

    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.

  20. Language abstractions for low level optimization techniques

    NASA Astrophysics Data System (ADS)

    Dévai, Gergely; Gera, Zoltán; Kelemen, Zoltán

    2012-09-01

    In case of performance critical applications programmers are often forced to write code at a low abstraction level. This leads to programs that are hard to develop and maintain because the program text is mixed up by low level optimization tricks and is far from the algorithm it implements. Even if compilers are smart nowadays and provide the user with many automatically applied optimizations, practice shows that in some cases it is hopeless to optimize the program automatically without the programmer's knowledge. A complementary approach is to allow the programmer to fine tune the program but provide him with language features that make the optimization easier. These are language abstractions that make optimization techniques explicit without adding too much syntactic noise to the program text. This paper presents such language abstractions for two well-known optimizations: bitvectors and SIMD (Single Instruction Multiple Data). The language features are implemented in the embedded domain specific language Feldspar which is specifically tailored for digital signal processing applications. While we present these language elements as part of Feldspar, the ideas behind them are general enough to be applied in other language definition projects as well.

  1. INFLUENCE OF SURGICAL TECHNIQUE IN THE PERITONEAL CARCINOMATOSIS SURGICAL WOUND IMPLANT: EXPERIMENTAL MODEL IN MICE

    PubMed Central

    ROSA, Roberto Maranhão; CAIADO, Rafael Coelho; REIS, Paulo Roberto de Melo; LACERDA, Elisângela de Paula Silveira; SUGITA, Denis Masashi; MRUÉ, Fátima

    2015-01-01

    Background The number of malignancies increased alarmingly. Surgery constitutes one of the most efficient therapeutic modalities for the treatment of solid tumors. The neoplastic implant in surgical wound is a complication whose percentage of occurrence reported in the literature is variable, but sets with high morbidity and therapeutic difficulties. Protecting the wound is one of the recommended principles of oncologic surgery. Aim To evaluate the influence of wound protection in the development of tumor implantation. Methods Sarcoma 180 tumor cells were used, with intraperitoneal inoculation in Swiss mice. After the establishment of neoplastic ascites, animals were randomized into two groups of 10, each group consisting of five males and five females. In both groups, laparotomy and manipulation of intra-abdominal organs was performed. In a group laparotomy was performed using the protection of the abdominal wound and the other group without it. On the 9th postoperative day macroscopic evaluation of the operative scar was performed, which was later removed for microscopic evaluation. Results There was microscopic infiltration of tumor cells in the wound of all animals. However, the group that held the protection, infiltration was less intense when compared to the group without it. The infiltration was also more severe in females than in males of the same group. Conclusion Tumor infiltration into the wound was more intense in the group in which the protection of the surgical site was not performed, and in females when compared to males of the same group. PMID:25861061

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

    PubMed Central

    Alvis-Miranda, Hernando Raphael; Farid-Escorcia, Hector; Alcalá-Cerra, Gabriel; Castellar-Leones, Sandra Milena; Moscote-Salazar, Luis Rafael

    2014-01-01

    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. PMID:25336831

  3. Surgical Technique of Anterolateral Approach for Tibial Plateau Fracture.

    PubMed

    Wang, Peng-cheng; Ren, Dong; Zhou, Bing

    2015-11-01

    A 66-year-old woman had sustained crush injury 3 hours prior to her presentation to our hospital. The diagnosis was defined as lateral tibial plateau fracture of the right knee (Schatzker III). Supine position was set up and a pad was put under the affected hip. After sterilization of the surgical field the sterilized sheets were placed beneath the leg in order to be higher than the other side. A rolled sheet was put under the knee joint so that the knee joint was flexed around 30° to 40°. After the surgical field was draped the skin was incised. Iliotibial band was incised by blade (not by electrotomy) and sharp dissection was performed in the Gerdy's tubercle. Capsulotomy was made by cutting the tibial meniscal ligament. Then the meniscus was tagged superiorly and the articular surface was clearly visualized. A window was made in the lateral cortex beneath the plateau, so the impacted fragment was elevated through the window. The metaphyseal void was filled by bone allograft. The placement of the raft-screw plate must be ensured that the raft screws passing the plate could purchase the subchondral bone. After perfect placement of the plate was defined, the femoral distractor was removed and the knee joint was relaxed. It was ensured that the alignment of the lower leg was normal, and then the other screws were inserted. Following placing drainage in the wound the iliotibial band was closed and the subcutaneous soft tissue and skin were closed in layer. PMID:26791810

  4. Combined operative technique with anterior surgical approach and video-assisted thoracoscopic surgical lobectomy for anterior superior sulcus tumours.

    PubMed

    Yokoyama, Yuhei; Chen, Fengshi; Aoyama, Akihiro; Sato, Toshihiko; Date, Hiroshi

    2014-11-01

    Video-assisted thoracoscopic surgery (VATS) has been widely used, but surgical resections of superior sulcus tumours remain challenging because of their anatomical location. For such cases, less-invasive procedures, such as the anterior transcervical-thoracic and transmanubrial approaches, have been widely performed because of their excellent visualization of the subclavian vessels. Recently, a combined operative technique with an anterior surgical approach and VATS for anterior superior sulcus tumours has been introduced. Herein, we report three cases of anterior superior sulcus tumours successfully resected by surgical approaches combined with a VATS-based lobectomy. In all cases, operability was confirmed by VATS, and upper lobectomies with hilar and mediastinal lymph node dissections were performed. Subsequently, dissections of the anterior inlet of the tumours were performed using the transmanubrial approach in two patients and the anterior trans-cervical-thoracic approach in one patient. Both approaches provided excellent access to the anterior inlet of the tumour and exposure of the subclavian vessels, resulting in radical resection of the tumour with concomitant resection of the surrounding anatomical structures, including the chest wall and vessels. In conclusion, VATS lobectomy combined with the anterior surgical approach might be an excellent procedure for the resection of anterior superior sulcus tumours. PMID:25028075

  5. Pediatric appendectomy: optimal surgical timing and risk assessment.

    PubMed

    Burjonrappa, Sathyaprasad; Rachel, Dana

    2014-05-01

    Appendicitis is one of the most common pediatric surgical problems. In the older surgical paradigm, appendectomy was considered to be an emergent procedure; however, with changes to resident work hours and other economic factors, the operation has evolved into an urgent and deliberately planned intervention. This paradigm shift in care has not necessarily seen universal buy-in by all stakeholders. Skeptics worry about the higher incidence of complications, particularly intra-abdominal abscess (IAA), associated with the delay to appendectomy with this strategy. Development of IAA after pediatric appendectomy greatly burdens the healthcare system, incapacitates patients, and limits family functionality. The risk factors that influence the development of IAA after appendectomy were evaluated in 220 children admitted to a large urban teaching hospital over a recent 1.5-year period. Preoperative risk factors included in the study were age, sex, weight, ethnicity, duration and nature of symptoms, white cell count, and ultrasound or computed tomography scan findings (appendicolith, peritoneal fluid, abscess, phlegmon), failed nonoperative management, antibiotics administered, and timing. Intraoperative factors included were timing of appendectomy, surgical and pathological findings of perforation, open or laparoscopic procedure, and use of staple or Endoloop to ligate the appendix. Postoperative factors included were duration and type of antibiotic therapy. There were 94 (43%) perforated and 126 (57%) nonperforated appendicitis during the study period. The incidence of postoperative IAA was 4.5 per cent (nine of 220). Children operated on after overnight antibiotics and resuscitation had a significantly lower risk of IAA as compared with children managed by other strategies (P < 0.0003). Of the preoperative factors, only the presence of a fever in the emergency department (P < 0.001) and identification of complicated appendicitis on imaging (P < 0.0001) were significant

  6. Osteoradionecrosis of the temporal bone: a surgical technique of treatment

    SciTech Connect

    Ma, K.H.; Fagan, P.A.

    1988-05-01

    Osteoradionecrosis of the temporal bone is a well-documented complication of radiotherapy to the ear, with potentially lethal complications. Three cases of advanced disease, treated surgically, are presented. In two of these, subtotal petrosectomy with blind-sac closure of the external auditory canal was carried out via an anterior approach. The enclosed space was obliterated with pedicled temporalis muscle. Primary healing took place. One case was similarly obliterated using a prolonged posterior incision. The wound broke down, requiring a microvascular free flap for closure. Radiotherapy jeopardizes the viability of skin flaps. An anterior incision bases the flap behind on the occipital and postauricular arteries. When radiotherapy has been used, this incision has theoretical and practical advantages over a standard posterior incision.

  7. Ileocolostomy. A technique for surgical management of equine cecal impaction.

    PubMed

    Craig, D R; Pankowski, R L; Car, B D; Hackett, R P; Erb, H N

    1987-01-01

    Several surgical alternatives have been described for the management of cecal impaction in the horse, but none has met with consistently successful results. This study was done to evaluate a surgical bypass of the cecum by anastomosis of the ileum to the right ventral colon (ileocolostomy). A ventral midline celiotomy was performed on nine adult ponies (155-350 kg) and a mechanically stapled 10 cm side-to-side ileocolostomy was created. In five ponies a complete cecal bypass (CCB) was created by transecting the ileum distal to the anastomosis. In the other four, an incomplete cecal bypass (ICB) was created with no interruption of the ileum. Six horses with clinical cecal impaction also underwent cecal bypass procedures. Five had a CCB and one had an ICB. All the ponies maintained body weight, had no change in consistency of the feces and had no abdominal pain during the 6 month observation period. At necropsy, the lengths of the lateral cecal band, lateral free band of the colon, and the diameter of the anastomotic stoma were compared to measurements made at surgery. The lateral cecal band length decreased significantly more in the CCB ponies than in the ICB ponies (p = 0.008). The anastomotic stoma diameter was significantly larger in the ICB group than in the CCB group (p = 0.032). Five of the six clinical cases recovered and returned to their previous activity. CCB by an ileocolostomy resulted in removal of the cecum from the functional flow of ingesta without complication in the ponies, and was successful in five clinical cases of cecal impaction. PMID:3507180

  8. Auricular reconstruction for microtia: Part II. Surgical techniques.

    PubMed

    Walton, Robert L; Beahm, Elisabeth K

    2002-07-01

    Reconstruction of the microtic ear represents one of the most demanding challenges in reconstructive surgery. In this review the two most commonly used techniques for ear reconstruction, the Brent and Nagata techniques, are addressed in detail. Unique to this endeavor, the originator of each technique has been allowed to submit representative case material and to address the pros and cons of the other's technique. What follows is a detailed, insightful overview of microtia reconstruction, as a state of the art. The review then details commonly encountered problems in ear reconstruction and pertinent technical points. Finally, a glimpse into the future is offered with an accounting of the advances made in tissue engineering as this technology applies to auricular reconstruction. PMID:12087261

  9. Surgical techniques and innovations in living related liver transplantation.

    PubMed Central

    Tanaka, K; Uemoto, S; Tokunaga, Y; Fujita, S; Sano, K; Nishizawa, T; Sawada, H; Shirahase, I; Kim, H J; Yamaoka, Y

    1993-01-01

    The authors successfully performed a series of 33 living related liver transplantations (LRLT) on children (15 males and 18 females, ranging from 7 months to 15 years of age) from June 1990 to May 1992, with the informed consent of their parents and the approval of the Ethics Committee of Kyoto University. Before operation, six of the children required intensive care, another 14 were hospitalized, and 13 were homebound. Donors (12 paternal and 21 maternal) were selected solely from the parents of the recipients on the basis of ABO blood group and graft/recipient size matching determined by computed tomography scanning. Procurement of graft was performed using ultrasonic aspirator and bipolar electrocautery without blood vessel clamping and without graft manipulation. All donors subsequently had normal liver function and returned to normal life. The left lateral segment (16 cases), left lobe (16 cases), or right lobe (one case) were used as grafts. The partial liver graft was transplanted into the recipient who underwent total hepatectomy with preservation of the inferior vena cava using a vascular side clamp. Twenty-seven of 33 recipients are alive and well with the original graft and have normal liver function. The patient survival rate was 89% (24/27) in elective cases and 50% (3/6) in emergent cases. The other six recipients had functioning grafts but died of extrahepatic complications. Complications of the graft were minimal in all cases. Hepatic vein stenosis, which occurred three times in two cases, was successfully treated by balloon dilatation. In cases with sclerotic portal vein, the authors anastomosed the portal vein of the graft to the confluence of the splenic vein and the superior mesenteric vein without a vascular graft, after experiencing a case of vascular graft thrombosis. After hepatic artery thrombosis occurred in one of the initial seven recipients whose arterial anastomosis was done with surgical loupe, microsurgery was introduced for hepatic

  10. Surgical Rehabilitation Techniques in Children with Poor Prognosis Short Bowel Syndrome.

    PubMed

    Dore, Mariela; Junco, Paloma Triana; Andres, Ane M; Sánchez-Galán, Alba; Amesty, Maria Virginia; Ramos, Esther; Prieto, Gerardo; Hernandez, Francisco; Lopez Santamaria, Manuel

    2016-02-01

    Intestinal failure (IF) requires a multidisciplinary management based on nutritional support, surgical and medical rehabilitation, and transplantation. The aim of this study is to review our experience with surgical rehabilitation techniques (SRTs: enteroplasty, Bianchi, Serial Transverse Enteroplasty Procedure [STEP]) in patients with short bowel syndrome (SBS) and poor prognosis due to complex abdominal pathology. We performed a single-center retrospective study of patients with IF evaluated for intestinal transplantation in the Intestinal Rehabilitation Unit who underwent an SRT. Nonparametric tests were used for statistical analysis.A total of 205 patients (107 males/98 females) with mean age of 25 ± 7 months were assessed for IF. A total of 433 laparotomies were performed on 130 patients including intestinal resection, enteroplasties, adhesiolysis, and transit reconstruction. SRT were performed in 22 patients: 12 enteroplasties, 8 STEPs, and 4 Bianchi procedures. All patients were parenteral nutrition (PN) dependent with different stages of liver disease: mild (13), moderate (5), and severe (4). The adaptation rate for patients who underwent enteroplasty, STEP, and Bianchi were 70, 63, and 25%, respectively, although the techniques are not comparable. Overall, intestinal adaptation was achieved in nine (41%) patients, and four (18%) patients showed significant reduction of PN needs. One child did not respond to SRT and did not meet transplantation criteria. The remaining eight (36%) patients were included on the waiting list for transplant: four were transplanted, two are still on the waiting list, and two died. Better outcomes were observed in milder cases of liver disease (mild 77%, moderate 40%, severe 25%) (p < 0.05). Conversely, a trend toward a poorer outcome was observed in cases with ultrashort bowel (p > 0.05). One patient required reoperation after a Bianchi procedure due to intestinal ischemia and six needed further re-STEP or adhesiolysis

  11. Leg-length inequalities following THA based on surgical technique.

    PubMed

    Nam, Denis; Sculco, Peter K; Abdel, Matthew P; Alexiades, Michael M; Figgie, Mark P; Mayman, David J

    2013-04-01

    Leg-length inequality after total hip arthroplasty (THA) is a source of patient morbidity and concern, potentially contributing to nerve palsies, low back pain, and abnormal gait mechanics. The purpose of this study was to compare the degrees of leg-length inequality in patients undergoing primary THA via 3 surgical approaches: anterior, conventional posterior, and posterior-navigated (ie, using computer navigation).The authors reviewed the most recent 90 patients who underwent primary unilateral THA performed by a senior surgeon using an anterior, conventional posterior, or posterior-navigated approach. Measurements of leg-length inequality of the operative extremity were performed using interischial and interteardrop reference lines. One-way analysis of variance demonstrated no statistical difference in postoperative absolute leg-length inequality using interischial (P=.11) and interteardrop (P=.90) reference lines between the 3 approaches. In addition, no significant difference existed in the number of outliers in each cohort when measured relative to the interteardrop reference line. When a leg-length inequality more than 5 mm was considered an outlier, 31.1%, 20.0%, and 23.3% of patients in the anterior, conventional posterior, and posterior-navigated groups, respectively, were outliers (P values range, .12 to .71). Mean±SD absolute-leg-length inequality relative to the interteardrop reference line in the anterior, conventional posterior, and posterior-navigated groups were 3.8±3.9, 3.9±3.0, and 3.9±2.7 mm, respectively. The anterior and posterior-navigated approaches demonstrated no superiority over the conventional posterior approach; all methods provided reliable leg-length equalization. PMID:23590775

  12. Step-by-step surgical technique for mandibular reconstruction with fibular free flap: application of digital technology in virtual surgical planning.

    PubMed

    Succo, G; Berrone, M; Battiston, B; Tos, P; Goia, F; Appendino, P; Crosetti, E

    2015-06-01

    At present, mandibular reconstruction with a fibular free flap is the gold standard for functional and esthetic rehabilitation after oncological surgery. The purpose of this study was to describe the computer-assisted mandibular reconstruction procedure adopting the customized solution Synthes ProPlan CMF. The study reports five consecutive patients with benign or malignant disease requiring mandibular reconstruction using a microvascular fibular free flap, pre-operative virtual planning, construction of cutting guides and customized laser pre-bent titanium plates. The surgical technique is discussed in a step-by-step fashion. The average post-operative hospital stay was 18 ± 3 days. Ischemia time was recorded in all five cases, with an average of 75 ± 8 min. No problems were encountered in any surgical step and there were no major complications. Excellent precision of cutting guides and a good fit of pre-bent plates were found on both the mandible and fibula. There was excellent precision in bone to bone contact and position between mandible and fibula graft. Measurement data from the pre-operative and post-operative CT scans were compared. The average difference (Δ) between programed segment lengths and CT control segment lengths was 0.098 ± 0.077 cm. Microsurgical mandibular reconstruction using a virtual surgical planning yields significantly shorter ischemia times and allows more precise osteotomies. The technology is becoming increasingly recognized for its ability to optimize surgical outcomes and minimize operating time. Considering that the extent of resection can be wider than predicted, this results in safer modeling of the fibula only after frozen sections have demonstrated the radicality of resection. PMID:24816745

  13. Robot assisted radical prostatectomy: how I do it. Part II: Surgical technique.

    PubMed

    Valdivieso, Roger F; Hueber, Pierre-Alain; Zorn, Kevin C

    2013-12-01

    The introduction of the "da Vinci Robotic Surgical System" (Intuitive Surgical, Sunnyvale, CA, USA) has been an important step towards a minimally invasive approach to radical prostatectomy. Technologic peculiarities, such as three-dimensional vision, wristed instrumentation with seven degrees of freedom of motion, lack of tremor, a 10x-magnification and a comfortable seated position for the surgeon has added value to the procedure for the surgeon and the patient. In this article, we describe the 9 step surgical technique for robot assisted radical prostatectomy (RARP) that is currently used in our institution (University of Montreal Hospital Center (CHUM) - Hopital St-Luc). We use the four-arm da Vinci Surgical System. Our experience with RARP is now over 250 cases with the senior surgeon having performed over 1200 RARPs and we have continually refined our technique to improve patient outcomes. PMID:24331353

  14. Penile prosthesis implant for erectile dysfunction: A new minimally invasive infrapubic surgical technique.

    PubMed

    Antonini, Gabriele; Busetto, Gian Maria; De Berardinis, Ettore; Giovannone, Riccardo; Vicini, Patrizio; Gentile, Vincenzo; Perito, Paul E

    2015-12-01

    Erectile dysfunction, the most common male sexual disorder after premature ejaculation, with its important impact on man and partner's sexuality and quality of life is a persistent inability to obtain and maintain an erection sufficient to permit satisfactory sexual performance. Non-surgical treatments with controversial results are usually applyed before surgical treatment that has reached high levels of satisfaction. We describe a new surgical technique to implant three-pieces penile prosthesis in patients suffering from erectile dysfunction (ED) not responding to conventional medical therapy or reporting side effects with such a therapy. Implantation of an inflatable prosthesis, for treatment of ED, is a safe and efficacious approach with high satisfaction reported by patients and partners. Surgical technique should be minimally invasive and latest technology equipment should be implanted in order to decrease common complications and to obtain a better aesthetic result. PMID:26766806

  15. A new technique for surgical treatment of vaginal agenesis using combined abdominal-perineal approach.

    PubMed

    Beksac, Mehmet Sinan; Salman, Mehmet Coskun; Dogan, Nasuh Utku

    2011-01-01

    Optimum therapeutic approach in vaginal agenesis has always been an area of extensive controversies. Although surgical management gained priority due to the evolution of techniques, there is currently no consensus in the literature regarding the best type of surgical approach. The most commonly preferred surgical procedure among gynecologists is McIndoe operation which involves the creation of a space between bladder and rectum, insertion of a mold covered with split-thickness skin graft into that neovaginal space, and use of postoperative vaginal dilation to avoid stenosis. However, many modifications have been introduced in time in an attempt to increase the success rates. In this paper, we describe two cases with vaginal agenesis with functioning uterus who were subjected to surgery by combined abdominal-perineal approach. The surgical technique also included the use of a specially designed vaginal mold made up of polymethyl methacrylate and use of Hyalobarrier gel which is an adhesion-preventing agent. PMID:21577259

  16. Subtle Lisfranc joint ligament lesions: surgical neoligamentplasty technique.

    PubMed

    Nery, Caio; Réssio, Cibele; Alloza, José Felipe Marion

    2012-09-01

    The results achieved with this technique after a mean follow-up of 8 years (85% excellent and good results) allow neoligamentplasty to be considered as a viable alternative to the classic procedures in the treatment of subtle intercuneiform and tarsometatarsal joint lesions. PMID:22938639

  17. A Review of Modern Surgical Hair Restoration Techniques

    PubMed Central

    Shiell, Richard C

    2008-01-01

    The field of hair restoration has had a chequered history. From the days of punch grafting to the present day techniques of follicular unit hair transplantation, the field has seen a number of new advances. This article reviews these developments. PMID:20300332

  18. Surgical repair of chronic rupture of the distal end of the biceps brachii. A modified anterior surgical repair technique.

    PubMed

    Sharma, Dinesh K; Goswami, Ved; Wood, Jane

    2004-06-01

    The authors have used a modified surgical technique for repair of the distal end of the biceps brachii in three patients who presented with chronic rupture, all more than 6 weeks old. All patients were males; two lesions were on the dominant right side and one was on the non-dominant left side. An anterior incision was made over the cubital fossa, a hole was drilled over the radial tuberosity and a simple pull-through technique with an Ethibond suture was used to attach the tendon to an endobutton over the posterior surface of the radius. All patients returned to their employment and preinjury activity levels by six months. There were no postoperative complications and clinically all repairs remained intact. The patients regained their normal range of movements in 3 months; all but one regained the endurance and strength of their bicep in 6 months as assessed by Cybex testing. Surgical repair of the distal end of the biceps using the technique reported has given excellent results in these three patients. PMID:15287407

  19. All-Arthroscopic Patch Augmentation of a Massive Rotator Cuff Tear: Surgical Technique

    PubMed Central

    Chalmers, Peter N.; Frank, Rachel M.; Gupta, Anil K.; Yanke, Adam B.; Trenhaile, Scott W.; Romeo, Anthony A.; Bach, Bernard R.; Verma, Nikhil N.

    2013-01-01

    Surgical management of massive rotator cuff tears remains challenging, with failure rates ranging from 20% to 90%. Multiple different arthroscopic and open techniques have been described, but there is no current gold standard. Failure after rotator cuff repair is typically multifactorial; however, failure of tendon-footprint healing is often implicated. Patch augmentation has been described as a possible technique to augment the biology of rotator cuff repair in situations of compromised tendon quality and has shown promising short-term results. The purpose of this article is to describe our preferred surgical technique for arthroscopic rotator cuff repair with patch augmentation. PMID:24400198

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

    PubMed Central

    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

  1. The surgical technique of bilateral sequential lung transplantation

    PubMed Central

    Hayanga, J. W. Awori

    2014-01-01

    Since the first successful lung transplant performed three decades ago, the technique of lung transplantation has evolved with acceptable short- and long-term outcomes such that it has become the standard for those with end stage pulmonary disease. Herein, we describe our current favored approach and discuss some of the current areas in need of further investigation as they relate to the technical aspects of the operation. PMID:25132973

  2. Machine Learning Techniques in Optimal Design

    NASA Technical Reports Server (NTRS)

    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

  3. Teaching and evaluation of basic surgical techniques: the University of British Columbia experience.

    PubMed

    Qayumi, A K; Cheifetz, R E; Forward, A D; Baird, R M; Litherland, H K; Koetting, S E

    1999-01-01

    Surgical technical education has traditionally followed an apprenticeship format. The need for innovative undergraduate programs using dry and wet labs prior to clinical exposure continues to be an area of debate. Specific programs have been described to improve surgical skills; however, an accepted platform for training and evaluation of surgical skills programs has not been recognized. Therefore, introduction of specific programs to teach undergraduate medical students surgical skills is essential. This article describes the Basic Surgical Technique (BST) program taught at the University of British Columbia and reports the effectiveness of this program in improving the practical skills of undergraduate medical students. The program includes BST I for third-year students performed in a dry lab setting, and BST II for medical student interns (MSI) performed at the animal laboratories using female domestic swine as subjects. A total of 87 students participated in the study. The program is designed using Piaget's and Vygotsky's pedagogical philosophy of "learning by doing." A semiquantitative method is used to measure and analyze the outcome of this project. Data were validated using student self-evaluation tests and by quantitative evaluation by surgical staff from the surgical wards. Results of this prospective project indicated that the BST program significantly (p < .05) improved the surgical performance of undergraduate students, and that the time lapse between BST I and II has had a negative impact in retention of acquired surgical skills. This study concludes that the BST program taught at the University of British Columbia significantly improves the surgical skills of medical students and improves their self-confidence during their internship. PMID:10630398

  4. Intraoperative neuromonitoring techniques in the surgical management of acoustic neuromas.

    PubMed

    Oh, Taemin; Nagasawa, Daniel T; Fong, Brendan M; Trang, Andy; Gopen, Quinton; Parsa, Andrew T; Yang, Isaac

    2012-09-01

    Unfavorable outcomes such as facial paralysis and deafness were once unfortunate probable complications following resection of acoustic neuromas. However, the implementation of intraoperative neuromonitoring during acoustic neuroma surgery has demonstrated placing more emphasis on quality of life and preserving neurological function. A modern review demonstrates a great degree of recent success in this regard. In facial nerve monitoring, the use of modern electromyography along with improvements in microneurosurgery has significantly improved preservation. Recent studies have evaluated the use of video monitoring as an adjunctive tool to further improve outcomes for patients undergoing surgery. Vestibulocochlear nerve monitoring has also been extensively studied, with the most popular techniques including brainstem auditory evoked potential monitoring, electrocochleography, and direct compound nerve action potential monitoring. Among them, direct recording remains the most promising and preferred monitoring method for functional acoustic preservation. However, when compared with postoperative facial nerve function, the hearing preservation is only maintained at a lower rate. Here, the authors analyze the major intraoperative neuromonitoring techniques available for acoustic neuroma resection. PMID:22937857

  5. Sentinel lymph node biopsy for conjunctival malignant melanoma: surgical techniques

    PubMed Central

    Wainstein, Alberto JA; Drummond-Lage, Ana P; Kansaon, Milhem JM; Bretas, Gustavo O; Almeida, Rodrigo F; Gloria, Ana LF; Figueiredo, Ana RP

    2015-01-01

    Background The purpose of this report is to examine the viability and safety of preoperative lymphoscintigraphy and radio guided sentinel lymph node (SLN) biopsy for conjunctival melanoma, and to identify the best technique to perform this procedure. Methods Three patients diagnosed with malignant melanoma of the conjunctiva underwent lymphoscintigraphy and SLN biopsy using a dual technique comprising isosulfan blue dye and technetium Tc 99m sulfur colloid. Each patient was anesthetized and the conjunctival melanoma was excised. SLNs were localized by a gamma probe, identified according to radioactivity and sentinel blue printing, and dissected, along with drainage of the associated lymphatic basins. The SLNs were evaluated by a pathologist using hematoxylin-eosin staining following serial sectioning and immunohistochemistry using a triple melanoma cocktail (S-100, Melan-A, and HMB-45 antigens). Results Two SLNs were stained in the jugular chain during preoperative lymphoscintigraphy in the first patient, two SLNs were identified in the preauricular and submandibular areas in the second patient, and two SLNs were identified in the submandibular and parotid areas in the third patient. All lymph nodes identified by lymphoscintigraphy were dissected and identified at surgery with 100% accuracy in all three patients. All SLNs were histologically and immunohistochemically negative. Patients had good cosmetic and functional results, and maintained their visual acuity and ocular motility. Conclusion Patients with conjunctival melanoma can undergo preoperative lymphoscintigraphy and SLN biopsy safely using radioactive technetium and isosulfan blue dye. PMID:25565762

  6. Cache Energy Optimization Techniques For Modern Processors

    SciTech Connect

    Mittal, Sparsh

    2013-01-01

    and veterans in the field of cache power management. It will help graduate students, CAD tool developers and designers in understanding the need of energy efficiency in modern computing systems. Further, it will be useful for researchers in gaining insights into algorithms and techniques for micro-architectural and system-level energy optimization using dynamic cache reconfiguration. We sincerely believe that the ``food for thought'' presented in this book will inspire the readers to develop even better ideas for designing ``green'' processors of tomorrow.

  7. A novel surgical technique for transverse sternal bone defects using flexible intramedullary nailing.

    PubMed

    Böcker, W; Euler, E; Schieker, M; Kettler, M; Mutschler, W

    2006-12-01

    Transverse sternal bone defects as a result of surgery or trauma remain an important clinical condition with serious sequelae. Patients sometimes complain of local pain during movement and breathing. Usually, defects are filled with prosthetic materials which remain permanently IN SITU. Small defects can be treated with autogenous bone grafts, whereas large defects are difficult to stabilize with common osteosynthetic techniques. Here, we report a new surgical technique using flexible intramedullary nailing ("Elastic Stable Intramedullary Nailing"--ESIN or "Embrochage Centro-Medullaire Elastique Stable"--ECMES) to stabilize a sternal defect after surgical removal of an osteochondral lesion. The defect was bridged by two elastic titanium nails and an autogenous corticocancellous bone graft. This new surgical technique showed a good clinical and functional outcome. PMID:17151979

  8. Global Optimization Techniques for Fluid Flow and Propulsion Devices

    NASA Technical Reports Server (NTRS)

    Shyy, Wei; Papila, Nilay; Vaidyanathan, Raj; Tucker, Kevin; Griffin, Lisa; Dorney, Dan; Huber, Frank; Tran, Ken; Turner, James E. (Technical Monitor)

    2001-01-01

    This viewgraph presentation gives an overview of global optimization techniques for fluid flow and propulsion devices. Details are given on the need, characteristics, and techniques for global optimization. The techniques include response surface methodology (RSM), neural networks and back-propagation neural networks, design of experiments, face centered composite design (FCCD), orthogonal arrays, outlier analysis, and design optimization.

  9. [Surgical treatment of hemorrhoids using Milligan-Morgan technique. Survey of 366 cases].

    PubMed

    Latteri, M; Grassi, N; Salanitro, L; Pantuso, G; Bottino, A; Gitto, C; Farro, G

    1991-10-31

    After a careful review of the Author's own case list and of the literature on this subject, Milligan-Morgans' technique is assessed and compared with different surgical techniques as far as early and late complications are concerned. The Authors conclude that the Milligan-Morgan technique is to be preferred because of its simplicity, safety and flexibility, particularly if associated with sphincterectomy, with or without rhagade, in order to prevent the cicatricial scars. PMID:1766559

  10. Laparoscopic Paravaginal Defect Repair: Surgical Technique and a Literature Review.

    PubMed

    Chinthakanan, Orawee; Miklos, John R; Moore, Robert D

    2015-11-01

    Paravaginal defects, commonly seen in patients with anterior vaginal wall prolapse, are due to the detachment of pubocervical fascia from the arcus tendineus fascia pelvis (ATFP), at or near its lateral attachment. The majority of anterior vaginal wall prolapse is thought to be caused by paravaginal defects. Richardson et al. first described and demonstrated the anatomy of the paravaginal defect, as well as described the initial technique of the abdominal approach to repair. Since that time, the laparoscopic approach for repair has been developed and described with success rates of laparoscopic paravaginal defect repair reported in the range of 60% to 89%. This minimally invasive approach to address anterior wall prolapse eliminates the need for a vaginal incision, reduces risk of vaginal shortening and can be completed at the same time as other laparoscopic procedures, such as hysterectomy, sacralcolpopexy, and/or Burch Urethropexy. Compared to the open abdominal approach, there is improved visualization, less risk of bleeding, and faster recovery with the laparoscopic method. Compared to an anterior colporrhaphy, laparoscopic paravaginal repair is a much more anatomic repair of lateral defects and does not result in vaginal shortening. The laparoscopic paravaginal repair should be considered as the first-line treatment of anterior vaginal wall prolapse caused by lateral defects, including at time of laparoscopic/robotic sacralcolpopexy. PMID:26680393

  11. Imaging techniques for infections in the surgical patient

    SciTech Connect

    Gerzof, S.G.; Oates, M.E.

    1988-02-01

    Gallium-67 citrate is easy to use and readily available, but the need to delay imaging for 2 to 4 days after injection hinders rapid diagnosis. Moreover, normal gastrointestinal activity limits its usefulness in evaluating the abdomen. Labeling leukocytes with Indium-111 oxine is a time-consuming, technically involved process, yet the images obtained at 24 hours will usually reveal sites of inflammation or infection. Although the techniques have similar sensitivities, the higher specificity of In-111 makes it the superior agent for many clinical situations. When there are localizing signs or symptoms or a reason to suspect a specific body region, CT or ultrasonography is the imaging modality of choice. Guided needle aspiration can then be performed and is usually diagnostic. Radionuclide imaging with either Ga-67 or In-111 is available as an adjunct if needle aspiration cannot be performed or is inconclusive. Since it provides total-body surveillance, radionuclide imaging is particularly useful for screening when there are no localizing signs and in cases of occult sepsis or fever of unknown origin. If positive, it can direct further imaging with CT or ultrasound. 46 references.

  12. Surgical Derotation Technique: A Novel Approach in the Management of Rotated Immature Permanent Incisor

    PubMed Central

    Krishnapriya, V; Sriram, CH; Reddy, Maheshwar KR

    2015-01-01

    ABSTRACT Surgical derotation is a method of placing a rotated tooth in normal alignment in a dental arch; surgically, immediately and permanently. It is a potentially convenient and cost-effective treatment modality as compared to conventional orthodontic procedure for rotated maxillary incisor with open apex. Here is a presentation of a severely rotated maxillary left permanent central incisor in a nine and half years old girl, with a radiographic evidence of immature root apex which was surgically derotated, orthodontically retroclined and intruded to its normal position. Postsurgical clinical and radiographic evaluation was done for a period of one and half years to confirm the vitality and continued physiological root formation of the affected tooth. How to cite this article: Dutta B, Krishnapriya V, Sriram CH, Reddy MKR. Surgical Derotation Technique: A Novel Approach in the Management of Rotated Immature Permanent Incisor. Int J Clin Pediatr Dent 2015;8(3):220-223. PMID:26604541

  13. Surgical Technique: Endoscopic Endonasal Transphenoidal Resection of a Large Suprasellar Mixed Germ Cell Tumor

    PubMed Central

    Chakravarthy, Vikram; Hanna, George; DeLos Reyes, Kennethy

    2016-01-01

    The endoscopic endonasal transphenoidal approach has proven to be a very versatile surgical approach for the resection of small midline skull base tumors. This is due to its minimally invasive nature, the potentially fewer neurological complications, and lower morbidity in comparison to traditional craniotomies. This surgical approach has been less commonly utilized for large midline tumors such as suprasellar germ cell tumors, due to numerous reasons including the surgeon’s comfort with the surgical approach, a higher chance of postoperative cerebrospinal fluid (CSF) leak, limited visualization due to arterial/venous bleeding, and limited working space. We present our surgical technique in the case of a large suprasellar and third ventricular mixed germ cell tumor that was resected via an endoscopic endonasal approach with favorable neurological outcome and no postoperative CSF leak. PMID:27014537

  14. A Practical Surgical Technique to Expose the Mental Nerve in Narrowing Genioplasty.

    PubMed

    Wang, Chenglong; Gui, Lai; Liu, Jianfeng

    2015-11-01

    In this article, the authors present a practical surgical technique using the anatomical character of the inferior alveolar nerve to fully expose the mental nerve (MN) in narrowing genioplasty. During the procedure, a rectangular mandibular outer cortex adjacent to the mental foramen is removed before the osteotomy. The objective is to avoid the injury of the MN from the reciprocating saw or bur and offer abundant space for the surgical operation. The technique has a minimal learning curve and will be useful to plastic surgeons to minimize unintentional cutting or pulling injury to the MN in narrowing genioplasty. PMID:26893979

  15. Latissimus dorsi tendon transfer for massive, irreparable posterosuperior rotator cuff tears: surgical technique.

    PubMed

    Qadir, Rabah; Romine, Lucas; Yao, David C; Duncan, Scott F M

    2014-09-01

    Massive rotator cuff tears remain a complex and challenging problem for both the patient and the surgeon. Although significant advancements in surgical techniques as well as technology for arthroscopic and mini-open rotator cuff repairs have been made, many massive tears result in failed repair with continued progressive tendon retraction and degeneration. In cases when primary tendon to bone healing is impractical, latissimus dorsi tendon transfer provides promising and reproducible clinical results. Herein, we present a latissimus tendon transfer surgical technique, a procedure we have used as a salvage operation for failed arthroscopic/mini-open primary rotator cuff repair. PMID:24854152

  16. Brain abscess and subdural empyema. Factors influencing mortality and results of various surgical techniques.

    PubMed Central

    Van Alphen, H A; Dreissen, J J

    1976-01-01

    The authors review the results of various surgical techniques in relation to mortality and morbidity in 100 consecutive cases of brain abscess and subdural empyema. The mortality rate is the same with total excision and fractional drainage of brain abscesses, although in acute and subacute cases slight differences between both techniques are seen. In terms of morbidity, fractional drainage appears to be more favourable than total excision. The authors believe that factors other than surgical procedure influence mortality in cases of brain abscess and subdural empyema. These factors are defined in detail. Images PMID:932767

  17. Techniques for optimizing inerting in electron processors

    NASA Astrophysics Data System (ADS)

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

    1993-07-01

    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 <0.1 ppm, good control techniques are required involving either recombination of the O 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. In this case, 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 can be determined 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, Ġ, 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.

  18. Recognition and Surgical Techniques for Management of Nonrecurrent Laryngeal Nerve during Carotid Endarterectomy.

    PubMed

    Jimenez, Juan Carlos; Jabori, Sinan; Gelabert, Hugh A; Moore, Wesley S; Quinones-Baldrich, William J; O'Connell, Jessica

    2016-05-01

    The presence of a nonrecurrent laryngeal nerve (NRLN) during carotid endarterectomy (CEA) may significantly limit the exposure of the surgical field during this operation. Although its reported incidence is rare, NRLN typically overlies the carotid bifurcation and failure to recognize this anatomic variation increases the risk of NRLN injury. A retrospective chart review of all patients who underwent CEA for hemodynamically significant extracranial carotid stenosis between January 2005 and December 2014 was performed. All patients with NRLN encountered intraoperatively were identified. Clinical outcomes, surgical techniques, and complications were reviewed and reported. Four left-sided NRLN were identified and 4 were right sided. No cranial nerve deficits or injuries occurred after CEA in patients where NRLN was encountered. Two distinct surgical techniques were used to manage patients with NRLN and they are discussed in detail. PMID:26965812

  19. Endoscopic Debridement for Treatment of Chronic Plantar Fasciitis: An Innovative Surgical Technique.

    PubMed

    Cottom, James M; Maker, Jared M

    2016-01-01

    Plantar fasciitis is one the most common pathologies seen by foot and ankle surgeons. When nonoperative therapy fails, surgical intervention is warranted. Various surgical procedures are available for the treatment of recalcitrant plantar fasciitis. The most common surgical management typically consists of open versus endoscopic plantar fascia release. The documented comorbidities associated with the release of the plantar fascia include lateral column overload and metatarsalgia. We present a new technique for this painful condition that is minimally invasive, allows visualization of the plantar fascia, and maintains the integrity of this fascia. Our hypothesis was that the use of endoscopic debridement of the plantar fascia would provide a minimally invasive technique with acceptable patient outcomes. PMID:26952313

  20. Colorectal resection in deep pelvic endometriosis: Surgical technique and post-operative complications

    PubMed Central

    Milone, Marco; Vignali, Andrea; Milone, Francesco; Pignata, Giusto; Elmore, Ugo; Musella, Mario; De Placido, Giuseppe; Mollo, Antonio; Fernandez, Loredana Maria Sosa; Coretti, Guido; Bracale, Umberto; Rosati, Riccardo

    2015-01-01

    AIM: To investigate the impact of different surgical techniques on post-operative complications after colorectal resection for endometriosis. METHODS: A multicenter case-controlled study using the prospectively collected data of 90 women (22 with and 68 without post-operative complications) who underwent laparoscopic colorectal resection for endometriosis was designed to evaluate any risk factors of post-operative complications. The prospectively collected data included: gender, age, body mass index, American Society of Anesthesiologists risk class, endometriosis localization (from anal verge), operative time, conversion, intraoperative complications, and post-operative surgical complications such as anastomotic dehiscence, bleeding, infection, and bowel dysfunction. RESULTS: A similar number of complicated cases have been registered for the different surgical techniques evaluated (laparoscopy, single access, flexure mobilization, mesenteric artery ligation, and transvaginal specimen extraction). A multivariate regression analysis showed that, after adjusting for major clinical, demographic, and surgical characteristics, complicated cases were only associated with endometriosis localization from the anal verge (OR = 0.8, 95%CI: 0.74-0.98, P = 0.03). After analyzing the association of post-operative complications and each different surgical technique, we found that only bowel dysfunction after surgery was associated with mesenteric artery ligation (11 out of 44 dysfunctions in the mesenteric artery ligation group vs 2 out of 36 cases in the no mesenteric artery ligation group; P = 0.03). CONCLUSION: Although further randomized clinical trials are needed to give a definitive conclusion, laparoscopic colorectal resection for deep infiltrating endometriosis appears to be both feasible and safe. Surgical technique cannot be considered a risk factor of post-operative complications. PMID:26715819

  1. SHIELDED-NEEDLE TECHNIQUE FOR SURGICALLY IMPLANTING RADIO-FREQUENCY TRANSMITTERS IN FISH

    EPA Science Inventory

    Protruding whip antenna radio transmitters were implanted in fish with abdominal pelvic fins. This surgical technique enables the transmitter to be positioned anywhere in the peritoneal cavity without piercing vital organs through the use of a shielded needle to guide an antenna ...

  2. Surgical implant techniques of left ventricular assist devices: an overview of acute and durable devices

    PubMed Central

    2015-01-01

    Left ventricular support for the failing heart has evolved to include short-term and long-term devices. These devices are implanted percutaneously and surgically. This manuscript provides a general overview of the contemporary, typically practiced, implant techniques with additional insight on minimally invasive approaches. PMID:26793329

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

    PubMed Central

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

    2015-01-01

    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. PMID:26424914

  4. Successful surgical repair of a triple cardiac rupture using modified cohesive double patch technique.

    PubMed

    Dorobantu, Lucian Florin; Stiru, Ovidiu; Iliescu, Vlad Anton

    2016-02-01

    Introduction The association between both left and right ventricular free wall ruptures (FWR) and post-infarction anterior ventricular septal defect (VSD) is an exceptional situation. Case report We present the case of a patient who developed a VSD and two FWRs (of the left and right ventricle, respectively) shortly after the onset of an anterior AMI. We surgically closed this complex rupture using the cohesive double patch technique with two Teflon patches combined with an infarct exclusion technique. The left and right ventricular patches were attached cohesively to the septal wall and the infarcted area was excluded without reducing the left ventricular cavity. Conclusion Association between post-infarction ventricular septal rupture and both left and right free wall ruptures are a very rare and dangerous situation. The modified cohesive double patch technique associated the modified Cooley technique seems to be the correct surgical solution. PMID:27385145

  5. Optimizing correlation techniques for improved earthquake location

    USGS Publications Warehouse

    Schaff, D.P.; Bokelmann, G.H.R.; Ellsworth, W.L.; Zanzerkia, E.; Waldhauser, F.; Beroza, G.C.

    2004-01-01

    Earthquake location using relative arrival time measurements can lead to dramatically reduced location errors and a view of fault-zone processes with unprecedented detail. There are two principal reasons why this approach reduces location errors. The first is that the use of differenced arrival times to solve for the vector separation of earthquakes removes from the earthquake location problem much of the error due to unmodeled velocity structure. The second reason, on which we focus in this article, is that waveform cross correlation can substantially reduce measurement error. While cross correlation has long been used to determine relative arrival times with subsample precision, we extend correlation measurements to less similar waveforms, and we introduce a general quantitative means to assess when correlation data provide an improvement over catalog phase picks. We apply the technique to local earthquake data from the Calaveras Fault in northern California. Tests for an example streak of 243 earthquakes demonstrate that relative arrival times with normalized cross correlation coefficients as low as ???70%, interevent separation distances as large as to 2 km, and magnitudes up to 3.5 as recorded on the Northern California Seismic Network are more precise than relative arrival times determined from catalog phase data. Also discussed are improvements made to the correlation technique itself. We find that for large time offsets, our implementation of time-domain cross correlation is often more robust and that it recovers more observations than the cross spectral approach. Longer time windows give better results than shorter ones. Finally, we explain how thresholds and empirical weighting functions may be derived to optimize the location procedure for any given region of interest, taking advantage of the respective strengths of diverse correlation and catalog phase data on different length scales.

  6. A Surgical Technique for the Management of Suction Cup-Induced Palatal Perforation: A Technical Note

    PubMed Central

    Rahpeyma, Amin

    2015-01-01

    Suction cap-induced palatal perforation is uncommon today. In the surgical management of such a complication, the surgeon should consider the large bony defect hidden behind the small slit in the palatal mucosa. In this article a case is presented,in which a combination of anteriorly based inferior turbinate flap and posteriorly based palatal submucosal flap solved the problem properly. The advantages of this technique are two-layer closure and predictability of the technique. PMID:26393223

  7. Simple, minimally invasive surgical technique for treatment of type 2 fractures of the distal clavicle.

    PubMed

    Levy, Ofer

    2003-01-01

    Neer type 2 fractures of the distal clavicle have a high rate of nonunion and delayed union. A simple, minimally invasive surgical technique using suture fixation is introduced. In this series 12 patients were treated with suture fixation of this fracture with absorbable suture material, resulting in union of all fractures. There was a rapid return to function and no complications. This technique allows simple, minimally invasive fixation with good fracture healing and early return to work and sports. PMID:12610482

  8. Optimization of a vector quantization codebook for objective evaluation of surgical skill.

    PubMed

    Kowalewski, Timothy M; Rosen, Jacob; Chang, Lily; Sinanan, Mika N; Hannaford, Blake

    2004-01-01

    Surgical robotic systems and virtual reality simulators have introduced an unprecedented precision of measurement for both tool-tissue and tool-surgeon interaction; thus holding promise for more objective analyses of surgical skill. Integrative or averaged metrics such as path length, time-to-task, success/failure percentages, etc., have often been employed towards this end but these fail to address the processes associated with a surgical task as a dynamic phenomena. Stochastic tools such as Markov modeling using a 'white-box' approach have proven amenable to this type of analysis. While such an approach reveals the internal structure of the of the surgical task as a process, it requires a task decomposition based on expert knowledge, which may result in a relatively large/complex model. In this work, a 'black box' approach is developed with generalized cross-procedural applications., the model is characterized by a compact topology, abstract state definitions, and optimized codebook size. Data sets of isolated tasks were extracted from the Blue DRAGON database consisting of 30 surgical subjects stratified into six training levels. Vector quantization (VQ) was employed on the entire database, thus synthesizing a lexicon of discrete, task-independent surgical tool/tissue interactions. VQ has successfully established a dictionary of 63 surgical code words and displayed non-temporal skill discrimination. VQ allows for a more cross-procedural analysis without relying on a thorough study of the procedure, links the results of the black-box approach to observable phenomena, and reduces the computational cost of the analysis by discretizing a complex, continuous data space. PMID:15544266

  9. A giant, complex fronto-ethmoidal ivory osteoma: Surgical technique in a resource-limited practice

    PubMed Central

    Adeleye, Amos Olufemi

    2010-01-01

    Background: Unlike small and medium size fronto-ethmoidal osteomas which are amenable to surgical excision through limited craniofacial openings, giant lesions require extensive and complex craniofacial dissection, and post lesionectomy reconstruction using an array of modern-day surgical adjuncts. This is a report of our surgical technique for the successful and esthetically fair operative resection of a giant fronto-ethmoidal osteoma in a difficult practice setting. Case Description: A 32-year-old Nigerian lady harbored a giant complex fronto-ethmoidal ivory osteoma. Deploying our understanding of modern-day advanced microsurgical anatomy and technique of skull base surgery, but under severe resource limitations, a radical total surgical resection was performed and an esthetically fair post lesionectomy reconstruction was achieved. The patient remains tumor-free in 20 months, so far, of postoperative follow-up. Conclusions: Even under severe resource limitations, inventive adaptations of modern-day skull base surgery techniques can facilitate hitherto unusual functional and esthetically successful resection of giant osteomas of the fronto-ethmoidal sinus complex. PMID:21245944

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

    PubMed Central

    Gani, Johan; Chee, Justin

    2016-01-01

    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. PMID:27437540

  11. Surgical repair of rectocele. Comparison of transvaginal and transanal approach and personal technique.

    PubMed

    Leanza, V; Intagliata, E; Leanza, G; Cannizzaro, M A; Zanghì, G; Vecchio, R

    2013-01-01

    Rectocele is defined as a herniation of the rectal wall inside the vagina due to a defect of the recto-vaginal septum. It is traditionally considered a posterior compartment damage with weakness of posterior vaginal wall support resulting in a bulging of the rectum into the vaginal cavity. One of the main causes of rectal prolapse is the operative vaginal birth, although the evidence of the defect may occur after many years The treatment of rectocele is surgical, and the approach can be transperineal, transvaginal, and transanal or, in selected cases, transperitoneal through open or laparoscopic techniques. In this study we compare two transvaginal surgical techniques - i.e. the perineal body anchorage to the posterior septum and the traditional Denonvilliers' transversal suture after removing of the vaginal skin, with the mostly performed transanal procedure, the STARR - comparing the data from the literature on their results. Mean hospital stay, rectal symptoms, dyspareunia, quality of life, recurrence rate and postoperative complications have been considered. Both transvaginal and transrectal surgical techniques are effective to solve posterior compartment defect and to improve the quality of life. Vaginal approach may interfere with the sexual activity; furthermore it is associated with minimal postoperative pain than the transanal approach. Better anatomic results are assured after endovaginal surgery, while better rectal function prevail after the transanal approach. Vaginal techniques are more suitable to gynecologists, whereas the transrectal ones are usually performed by colo-proctologists or general surgeons. PMID:24342163

  12. Distal humerus shear-fractures: “Built-on” surgical technique

    PubMed Central

    Rapariz, Jose M.; Martin, Silvia; Far-Riera, Aina; Lirola-Palmero, Serafin

    2014-01-01

    When treating a distal humeral shear fracture, comminution of the lateral column may preclude the reconstruction of the lateral articular fragments. In this article a new strategy for the management lateral column comminuted shear-fractures (LCCSF) is presented, called the “built-on” surgical technique. Three goals are obtained by this technique: (1) Restoration of the lateral column bone stock; (2) Provision of a solid scaffold for the repair of the lateral ulnar collateral ligament (LUCL); and (3) Provision of a sable platform for the reconstruction and fixation of the articular fragments. We will obtain these goals through the following surgical steps: 1/ Reconstruction of the lateral trochlea. 2/ Reconstruction of the lateral column 3/ Fixation of the Capitellum 4/ Reconstruction of the LUCL PMID:24926163

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

    PubMed

    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. PMID:25840860

  14. Management of posttraumatic kyphosis: surgical technique to facilitate a combined approach.

    PubMed

    Marré, Bartolomé

    2005-07-01

    This report describes a variation of the "posterior-anterior-posterior" surgical techniques to correct posttraumatic kyphosis of the thoracic and lumbar spine with the USS internal fixator. This modification is based on the use of "temporary screws" to mark the entrance of the pedicles in the first stage of the operation (posterior approach, with the patient in prone position). Approaching both columns of the spine simultaneously facilitates correction of the kyphotic defect and permits 360 reconstruction of the spine. PMID:15993120

  15. Toric intraocular lenses: historical overview, patient selection, IOL calculation, surgical techniques, clinical outcomes, and complications.

    PubMed

    Visser, Nienke; Bauer, Noël J C; Nuijts, Rudy M M A

    2013-04-01

    We present an overview of currently available toric intraocular lenses (IOLs) and multifocal toric IOLs. Relevant patient selection criteria, IOL calculation issues, and surgical techniques for IOL implantation are discussed. Clinical outcomes including uncorrected visual acuity, residual refractive astigmatism, and spectacle independency, which have been reported for both toric IOLs and multifocal toric IOLs, are reviewed. The incidence of misalignment, the most important complication of toric IOLs, is determined. Finally, future developments in the field of toric IOLs are discussed. PMID:23522584

  16. A surgical glove port technique for laparoscopic-assisted ovariohysterectomy for pyometra in the bitch.

    PubMed

    Becher-Deichsel, Anja; Aurich, Jörg E; Schrammel, Nadine; Dupré, Gilles

    2016-07-15

    The objective of the study was to describe the feasibility of a glove port technique for laparoscopic-assisted surgical treatment of canine pyometra. In this retrospective case series, a total of 10 female dogs (median age 7 years, range 5.5-10.5 years; median weight 37.0 kg, range 12.9-64.0 kg) with pyometra were included. A multiaccess port was created from a surgical glove attached to an Alexis wound retractor and placed in the ventral midline between the middle and caudal third of the distance between umbilicus and pubic rim. A vessel sealing device was used for transection of the ovarian pedicle. The port size was selected on the basis of maximum uterine diameter determined by ultrasound. Median incision length was 5.0 cm (range 3.1-7.7 cm) for a maximum uterine diameter of 4.0 cm (range 2.0-7.0 cm). Median surgical time was 57 minutes (range 48-65 minutes). No case had to be converted to open celiotomy. Complications included one case of minor, self-limiting splenic trauma by the endoscope. In eight dogs, the distended uterine horns endangered safe access to the ovarian pedicle, and the vessel sealing device was inserted through a second cannula placed periumbilically. Extension of the original incision was necessary to exteriorize organs in two dogs. All dogs recovered quickly and were discharged either on the day of surgery or 1 day thereafter. In conclusion, a surgical glove port technique in combination with an Alexis wound retractor is feasible for surgical laparoscopic treatment of canine pyometra up to a diameter of 7 cm. PMID:27039076

  17. Cranial cruciate ligament rupture in the dog--a retrospective study comparing surgical techniques.

    PubMed

    Moore, K W; Read, R A

    1995-08-01

    Three surgical techniques, grouped as intra-articular techniques, extracapsular techniques and fibular head transposition, were used for repair of the cranial cruciate ligament (CCL)-deficient stifle in 113 dogs over a 4 year 4 month period. The clinical outcome of the techniques were compared using information provided by the owners and physical examination. Regardless of surgical technique, 85.7 to 91.0% of dogs showed clinical improvement after surgery. However, less than 50% of dogs became clinically sound on the operated leg and 9.0 to 14.3% of dogs remained persistently lame on the operated leg. No statistical association was found between result after surgery and age, body weight, sex, duration of injury before surgery, association with injury, tibial plateau angle, degree of radiographic osteoarthritis before surgery or the presence of concurrent medial meniscal injury. On physical examination, extra-capsular techniques appeared superior to the fibular head transposition in terms of joint stability and limb function. Concurrent medial meniscal injury necessitating meniscectomy existed in 48.0% of cases. Twenty-two percent of dogs ruptured their contralateral CCL at an average of 14 months after the first. PMID:8579557

  18. Optimal surgical options for descending necrotizing mediastinitis of the anterior mediastinum.

    PubMed

    Guan, Xin; Zhang, Wei Jie; Liang, Xi; Liang, Xiang; Wang, Feng; Guo, Xiang; Zhou, Yaodong

    2014-09-01

    The mortality rates from descending necrotizing mediastinitis (DNM) are between 25 and 40 % mainly because of delayed diagnosis and inappropriate surgical treatment. This study was undertaken to examine two surgical options for DNM and determine the optimal surgical option for DNM of the anterior mediastinum. Fifteen cases of DNM of the anterior mediastinum, January 2001 and October 2010, were retrospectively reviewed. Eleven were anterosuperior mediastinitis, with infection located above the tracheal bifurcation and four had infections involving the entire anterior mediastinum. Depending on the location of mediastinitis, open drainage of the submandibular and neck abscesses, in addition to other surgical treatments, was performed. If the infection was anterosuperior, transcervical mediastinal drainage or thoracotomy was performed. If the entire anterior mediastinum was involved, necrotic tissue was removed with thoracoscopic via subxiphoid incision, the bilateral pleurae were opened for drainage, and a tunnel connecting the neck incision and the subxiphoid incision through the whole anterior mediastinum was made for drainage. The anterosuperior mediastinitis cases were treated with either transcervical mediastinal drainage (n = 8) or thoracotomy (n = 3). Patients healed after an average of 24.5 and 20.0 days in the hospital, respectively. For the four other cases, one patient died of septic shock, while the other three patients were healed after and an average of 43.3 days in the hospital. Mortality rate was 6.7 %. The surgical procedure used to treat DNM should be selected according to the location of the infection. DNM involving the anterosuperior mediastinum can be treated by transcervical mediastinal drainage. If anterosuperior mediastinitis spreads to the side of the trachea, open thoracotomy is a suitable therapy. If the entire anterior mediastinum is involved, debridement and drainage of the anterior mediastinum should be performed with a thoracoscope via

  19. Objective measurement of the deviated nose and a review of surgical techniques for correction.

    PubMed

    Erdem, Tamer; Ozturan, Orhan

    2008-03-01

    Although many surgical techniques have been introduced, there are few clinical studies investigating postoperative results in crooked nose deformity. The aim of this study is to discuss the surgical choices for specific deformities and to report the long-term quantitative surgical results of our cases. One hundred and twenty cases (38 women, 82 men) with crooked noses (48 I-shaped, 72 C-shaped) operated on by the authors were included in the study. The patients have been followed for 6 to 46 months (mean 19 months) postoperatively. The Scion Image software program was utilized for numerical measurement of the nasal crookedness. In cases with I-shaped and C-shaped crooked nose deformity, preoperative and postoperative angle values were as follows: 6.84 +/- 2.58 degrees, 2.01 +/- 1.53, 152.97 +/- 9.03 degrees and 173.67 +/- 4.55 degrees, respectively. In both groups, postoperative correction rates were statistically significant (p = 0.0001). Despite these results, patients undergoing surgical treatment should be informed about imperfect outcomes, possibility of persistent deformity and the need of revision surgery. PMID:18444494

  20. [NEW SURGICAL APPROACH IN PRIMARY OPEN-ANGLE GLAUCOMA: XEN GEL STENT A MINIMALLY INVASIVE TECHNIQUE].

    PubMed

    Dupont, G; Collignon, N

    2016-02-01

    Primary open-angle glaucoma is a progressive ocular disease affecting adults and associated with visual field defect. The aim of its treatment is to lower the ocular pressure by means of ocular drops, laser or surgery. To date, traditional surgical techniques still remain quite invasive, but recent research efforts have been made with a view to develop minimally invasive techniques. The Xen Gel Stent is one of them. It allows a safe and efficient lowering of ocular pressure by creating a sub-conjunctival flow, following an ab interno procedure that highly preserves the architecture of the treated eye. PMID:27141652

  1. Unique Technique for Open Surgical Repair after Failed Endovascular Aneurysm Repair with Proximal Anastomoses

    PubMed Central

    Hirota, Jun; Mori, Kazuki; Shuto, Takashi; Okamoto, Keitaro; Sato, Aiko; Wada, Tomoyuki; Anai, Hirofumi; Miyamoto, Shinji

    2016-01-01

    Endovascular aortic aneurysm repair (EVAR) has revolutionized the management of abdominal aortic aneurysms (AAAs), with lower perioperative morbidity and mortality compared to conventional surgical repair. However, late secondary re-interventions after EVAR are still needed before aneurysm rupture in many cases. A patient with impending rupture of an AAA associated with a type I endoleak 7 years after EVAR who was successfully treated with a unique technique of fixation of the proximal aortic neck taking into account the structure of the stent graft is reported. This technique offers a safe solution to late open conversion after failed EVAR. PMID:27375808

  2. A mesh gradient technique for numerical optimization

    NASA Technical Reports Server (NTRS)

    Willis, E. A., Jr.

    1973-01-01

    A class of successive-improvement optimization methods in which directions of descent are defined in the state space along each trial trajectory are considered. The given problem is first decomposed into two discrete levels by imposing mesh points. Level 1 consists of running optimal subarcs between each successive pair of mesh points. For normal systems, these optimal two-point boundary value problems can be solved by following a routine prescription if the mesh spacing is sufficiently close. A spacing criterion is given. Under appropriate conditions, the criterion value depends only on the coordinates of the mesh points, and its gradient with respect to those coordinates may be defined by interpreting the adjoint variables as partial derivatives of the criterion value function. In level 2, the gradient data is used to generate improvement steps or search directions in the state space which satisfy the boundary values and constraints of the given problem.

  3. Optimal control techniques for active noise suppression

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Keeling, S. L.; Silcox, R. J.

    1988-01-01

    Active suppression of noise in a bounded enclosure is considered within the framework of optimal control theory. A sinusoidal pressure field due to exterior offending noise sources is assumed to be known in a neighborhood of interior sensors. The pressure field due to interior controlling sources is assumed to be governed by a nonhomogeneous wave equation within the enclosure and by a special boundary condition designed to accommodate frequency-dependent reflection properties of the enclosure boundary. The form of the controlling sources is determined by considering the steady-state behavior of the system, and it is established that the control strategy proposed is stable and asymptotically optimal.

  4. Comparative study of two surgical techniques for root coverage of large recessions in heavy smokers.

    PubMed

    Reino, Danilo M; Maia, Luciana P; Novaes, Arthur B; Souza, Sérgio L S

    2015-01-01

    Reduced root coverage due to diminished periodontal vascularity can be expected in heavy smokers. The aim of this study was to evaluate the root coverage obtained for large gingival recessions in heavy smokers using two different surgical techniques. Twenty heavy smokers were selected. Each patient had large, bilateral Miller class I or II gingival recessions (Control Group (CG): 3.30 ± 1.29; Test Group (TG): 3.45 ± 0.80) on nonmolar teeth. Clinical measurements of probing pocket depth (PPD), clinical attachment level (CAL), recession height (RH), keratinized mucosa height (KMH), and keratinized mucosa thickness (KMT) were determined at baseline and after 12 months. One side received a coronally positioned flap (CPF), while the contralateral side received the extended flap technique (EFT), both procedures carried out in conjunction with a subepithelial connective tissue graft (SCTG). Saliva samples to measure cotinine levels were taken at baseline and after 12 months as an indicator of the level of exposure to nicotine. Intergroup and intragroup analysis showed no statistical differences for the evaluated clinical parameters. Patients maintained the same exposure to smoke during the evaluation period. Both techniques resulted in low root coverage (CPF: 48.60%; EFT: 54.28%), but both techniques were effective in decreasing the gingival recessions (P ≤ 0.01). The variables smoke exposure, root coverage, and the thickness and height of keratinized tissue were subjected to linear regression. Regardless of the surgical technique used, heavy smoking strongly limits root coverage, especially for large recessions. PMID:26171447

  5. Optimization Techniques for College Financial Aid Managers

    ERIC Educational Resources Information Center

    Bosshardt, Donald I.; Lichtenstein, Larry; Palumbo, George; Zaporowski, Mark P.

    2010-01-01

    In the context of a theoretical model of expected profit maximization, this paper shows how historic institutional data can be used to assist enrollment managers in determining the level of financial aid for students with varying demographic and quality characteristics. Optimal tuition pricing in conjunction with empirical estimation of…

  6. Axillary dissection in primary breast cancer: variations of the surgical technique and influence on morbidity

    PubMed Central

    Wojcinski, Sebastian; Nuengsri, Sirin; Hillemanns, Peter; Schmidt, Werner; Deryal, Mustafa; Ertan, Kubilay; Degenhardt, Friedrich

    2012-01-01

    Lymphedema of the arm is the most common and impairing complication after breast cancer surgery with axillary lymph node dissection (ALND). Our prospective study evaluated the effect of two different surgical techniques for ALND on postoperative morbidity. Patients were scheduled to undergo ALND. Patients in group 1 (n = 17) underwent the most common and standard technique of ALND, which uses sharp dissection of the tissue and subsequent electro-coagulation of bleedings. Patients in group 2 (n = 17) underwent a modified standard technique of ALND with clamping and ligatures of all resection margins. Postoperative wound secretion was quantified and patients were followed up for 6 months to assess long-term morbidity. The variations in surgical technique had no significant influence on the outcome variables. However, patients in group 2 showed a tendency to less wound secretion (713 versus 802 mL; P = nonsignificant), a decreased rate of immediate postoperative seromas (11.8 versus 23.5%; P = nonsignificant) and less lymphedema after 3 months (29.4 versus 41.2%; P = nonsignificant). Moreover, the number of resected lymph nodes correlated with the total amount of drained fluid (P = 0.006), the duration of the drain (P = 0.015), and the risk for the development of lymphedema after 3 months (P = 0.016). The described variations in surgical technique had no influence on the outcomes of the patients. The number of resected axillary lymph nodes remains the most important risk factor for treatment-related morbidity. Therefore, a well-balanced choice of the extent of the axillary dissection should be the surgeon’s main concern. PMID:22570566

  7. Axillary dissection in primary breast cancer: variations of the surgical technique and influence on morbidity.

    PubMed

    Wojcinski, Sebastian; Nuengsri, Sirin; Hillemanns, Peter; Schmidt, Werner; Deryal, Mustafa; Ertan, Kubilay; Degenhardt, Friedrich

    2012-01-01

    Lymphedema of the arm is the most common and impairing complication after breast cancer surgery with axillary lymph node dissection (ALND). Our prospective study evaluated the effect of two different surgical techniques for ALND on postoperative morbidity. Patients were scheduled to undergo ALND. Patients in group 1 (n = 17) underwent the most common and standard technique of ALND, which uses sharp dissection of the tissue and subsequent electro-coagulation of bleedings. Patients in group 2 (n = 17) underwent a modified standard technique of ALND with clamping and ligatures of all resection margins. Postoperative wound secretion was quantified and patients were followed up for 6 months to assess long-term morbidity. The variations in surgical technique had no significant influence on the outcome variables. However, patients in group 2 showed a tendency to less wound secretion (713 versus 802 mL; P = nonsignificant), a decreased rate of immediate postoperative seromas (11.8 versus 23.5%; P = nonsignificant) and less lymphedema after 3 months (29.4 versus 41.2%; P = nonsignificant). Moreover, the number of resected lymph nodes correlated with the total amount of drained fluid (P = 0.006), the duration of the drain (P = 0.015), and the risk for the development of lymphedema after 3 months (P = 0.016). The described variations in surgical technique had no influence on the outcomes of the patients. The number of resected axillary lymph nodes remains the most important risk factor for treatment-related morbidity. Therefore, a well-balanced choice of the extent of the axillary dissection should be the surgeon's main concern. PMID:22570566

  8. Surgical Technique for Spinal Cord Delivery of Therapies: Demonstration of Procedure in Gottingen Minipigs

    PubMed Central

    Federici, Thais; Hurtig, Carl V.; Burks, Kentrell L.; Riley, Jonathan P.; Krishna, Vibhor; Miller, Brandon A.; Sribnick, Eric A.; Miller, Joseph H.; Grin, Natalia; Lamanna, Jason J.; Boulis, Nicholas M.

    2012-01-01

    This is a compact visual description of a combination of surgical technique and device for the delivery of (gene and cell) therapies into the spinal cord. While the technique is demonstrated in the animal, the procedure is FDA-approved and currently being used for stem cell transplantation into the spinal cords of patients with ALS. While the FDA has recognized proof-of-principle data on therapeutic efficacy in highly characterized rodent models, the use of large animals is considered critical for validating the combination of a surgical procedure, a device, and the safety of a final therapy for human use. The size, anatomy, and general vulnerability of the spine and spinal cord of the swine are recognized to better model the human. Moreover, the surgical process of exposing and manipulating the spinal cord as well as closing the wound in the pig is virtually indistinguishable from the human. We believe that the healthy pig model represents a critical first step in the study of procedural safety. PMID:23242422

  9. Surgical Removal of Neglected Soft Tissue Foreign Bodies by Needle-Guided Technique

    PubMed Central

    Ebrahimi, Ali; Radmanesh, Mohammad; Rabiei, Sohrab; kavoussi, Hossein

    2013-01-01

    Introduction: The phenomenon of neglected foreign bodies is a significant cause of morbidity in soft tissue injuries and may present to dermatologists as delayed wound healing, localized cellulitis and inflammation, abscess formation, or foreign body sensation. Localization and removal of neglected soft tissue foreign bodies (STFBs) is complex due to possible inflammation, indurations, granulated tissue, and fibrotic scar. This paper describes a simple method for the quick localization and (surgical) removal of neglected STFBs using two 23-gauge needles without ultrasonographic or fluoroscopic guidance. Materials and Methods: A technique based on the use of two 23-gauge needles was used in 41 neglected STFBs in order to achieve proper localization and fixation of foreign bodies during surgery. Results: Surgical removal was successful in 38 of 41 neglected STFBs (ranging from 2–13mm in diameter). Conclusion: The cross-needle-guided technique is an office-based procedure that allows the successful surgical removal of STFBs using minimal soft tissue exploration and dissection via proper localization, fixation, and propulsion of the foreign body toward the surface of the skin. PMID:24303416

  10. The many faces of ALPPS: surgical indications and techniques among surgeons collaborating in the international registry

    PubMed Central

    Buac, Suzana; Schadde, Erik; Schnitzbauer, Andreas A.; Vogt, Kelly; Hernandez-Alejandro, Roberto

    2016-01-01

    Background ALPPS was developed to induce accelerated future liver remnant (FLR) hypertrophy in order to increase hepatic tumour resectability and reduce the risk of post-operative liver failure. While early studies demonstrated concerning complication rates, others reported favourable results. This inconsistency may be due to variability in surgical indications and technique. Methods A web-based survey was sent to surgeons participating in the International ALPPS Registry in September of 2014. Questions addressed surgeon demographics and training, surgical indications and technique, and clinical management approaches. Results Fifty six out of 85 surgeons from 78 centers responded (66%) and half (n = 30) had training in liver transplantation. Forty seven (84%) did not reserve ALPPS solely for colorectal liver metastases (CRLM) and 30 (54%) would perform ALPPS for an FLR over 30%. Neoadjuvant chemotherapy for CRLM was recommended by 37 (66%) respondents. Surgical approaches varied considerably, with 30% not preserving outflow to the middle hepatic vein and 39% believing it necessary to skeletonize the hepatoduodenal ligament. Twenty five (45%) surgeons have observed segment 4 necrosis. Conclusion There is considerable variability in how ALPPS is performed internationally. This heterogeneity in practice patterns may explain the current incongruity in published outcomes, and highlights the need for standardization. PMID:27154808

  11. GPU-based Efficient Realistic Techniques for Bleeding and Smoke Generation in Surgical Simulators

    PubMed Central

    Halic, Tansel; Sankaranarayanan, Ganesh; De, Suvranu

    2010-01-01

    Background In actual surgery, smoke and bleeding due to cautery processes, provide important visual cues to the surgeon which have been proposed as factors in surgical skill assessment. While several virtual reality (VR)-based surgical simulators have incorporated effects of bleeding and smoke generation, they are not realistic due to the requirement of real time performance. To be interactive, visual update must be performed at least 30 Hz and haptic (touch) information must be refreshed at 1 kHz. Simulation of smoke and bleeding is, therefore, either ignored or simulated using highly simplified techniques since other computationally intensive processes compete for the available CPU resources. Methods In this work, we develop a novel low-cost method to generate realistic bleeding and smoke in VR-based surgical simulators which outsources the computations to the graphical processing unit (GPU), thus freeing up the CPU for other time-critical tasks. This method is independent of the complexity of the organ models in the virtual environment. User studies were performed using 20 subjects to determine the visual quality of the simulations compared to real surgical videos. Results The smoke and bleeding simulation were implemented as part of a Laparoscopic Adjustable Gastric Banding (LAGB) simulator. For the bleeding simulation, the original implementation using the shader did not incur in noticeable overhead. However, for smoke generation, an I/O (Input/Output) bottleneck was observed and two different methods were developed to overcome this limitation. Based on our benchmark results, a buffered approach performed better than a pipelined approach and could support up to 15 video streams in real time. Human subject studies showed that the visual realism of the simulations were as good as in real surgery (median rating of 4 on a 5-point Likert scale). Conclusions Based on the performance results and subject study, both bleeding and smoke simulations were concluded to be

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

    PubMed Central

    JUNQUEIRA, Marina Azevedo; CUNHA, Nayara Nery Oliveira; SILVA, Lidiane Lucas Costa e; ARAÚJO, Leandro Borges; MORETTI, Ana Beatriz Silveira; COUTO FILHO, Carlos Eduardo Gomes; SAKAI, Vivien Thiemy

    2014-01-01

    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. PMID:25025566

  13. Computer-assisted surgical techniques: can they really improve laser surgery?

    NASA Astrophysics Data System (ADS)

    Reinisch, Lou; Arango, Pablo; Howard, John G.; Mendenhall, Marcus H.; Ossoff, Robert H.

    1995-05-01

    As part of our Computer-Assisted Surgical Techniques (CAST) program, we use computers to guide surgical lasers, create minimal incision widths, regulate the rate of tissue ablation, monitor the types of tissue being ablated with photo-acoustic feedback, and track and compensate for patient motions due to respiration and heart beat. The union of the computer, robotics and lasers can assist the surgeon and permit several new applications. Although these advances in laser surgery appear to have obvious benefits, it is important to evaluate and quantify the clinical advantages. We have compared the CAST system to manually controlled laser surgery and studied the wound healing after laser incision. We have found definite advantages to the CAST system. However, the computer, alone, cannot compensate for the thermal damage lateral to the incision site. The results suggest the need for motion tracking and compensation to be a part of the CAST system.

  14. Neural network training with global optimization techniques.

    PubMed

    Yamazaki, Akio; Ludermir, Teresa B

    2003-04-01

    This paper presents an approach of using Simulated Annealing and Tabu Search for the simultaneous optimization of neural network architectures and weights. The problem considered is the odor recognition in an artificial nose. Both methods have produced networks with high classification performance and low complexity. Generalization has been improved by using the backpropagation algorithm for fine tuning. The combination of simple and traditional search methods has shown to be very suitable for generating compact and efficient networks. PMID:12923920

  15. Components separation in complex ventral hernia repair: surgical technique and post-operative outcomes.

    PubMed

    Ross, Samuel W; Oommen, Bindhu; Heniford, B Todd; Augenstein, Vedra A

    2014-03-01

    There are over 350,000 ventral hernia repairs (VHR) performed in the United States annually and a variety of laparoscopic and open surgical techniques are described and utilized. Complex ventral hernias such as recurrent hernias, those with infected mesh, open wounds, coexisting enteric fistulas, parastomal hernias, and massive hernias-especially those with loss of abdominal domain-require sophisticated repair techniques. Many of these repairs are performed via an open approach. Ideally, the aim is to place mesh under the fascia with a large overlap of the defect and obtain primary fascial closure. However, it is often impossible to bring together fascial edges in very large hernias. Component separation is an excellent surgical technique in selected patients which involves release of the different layers of the abdominal wall and in turn helps accomplish primary fascial approximation. The posterior rectus sheath, external oblique or the transverse abdominis fascia can be cut and allows for closure of fascia in a tension free manner in a majority of patients. In this chapter we describe the various techniques for component separation, indications for use, how to select an appropriate type of release and post-operative outcomes. PMID:24700223

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

    PubMed Central

    Khairnar, Mayur; Pawar, Babita; Khairnar, Darshana

    2014-01-01

    Ankyloglossia or “tongue-tie” is a congenital anomaly caused by tight lingual frenulum that abnormally connects the tongue base to the floor of the mouth. Ankyloglossia can results in difficulty during speech and deglutition. This case series presents a novel surgical technique in the management of ankyloglossia in using presuturing technique in which different sets of sutures are given on lingual frenum before severing it. This results in reduced opening of the wound, minimal bleeding, pain and discomfort. Two male patients with severe ankyloglossia had been managed with this technique and after 2 years of follow-up of these cases showed satisfactory protrusive and lateral movement of the tongue with minimal scarring and discomfort. PMID:25598942

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

    PubMed

    Khairnar, Mayur; Pawar, Babita; Khairnar, Darshana

    2014-01-01

    Ankyloglossia or "tongue-tie" is a congenital anomaly caused by tight lingual frenulum that abnormally connects the tongue base to the floor of the mouth. Ankyloglossia can results in difficulty during speech and deglutition. This case series presents a novel surgical technique in the management of ankyloglossia in using presuturing technique in which different sets of sutures are given on lingual frenum before severing it. This results in reduced opening of the wound, minimal bleeding, pain and discomfort. Two male patients with severe ankyloglossia had been managed with this technique and after 2 years of follow-up of these cases showed satisfactory protrusive and lateral movement of the tongue with minimal scarring and discomfort. PMID:25598942

  18. A systematic review on skin complications of bone-anchored hearing aids in relation to surgical techniques.

    PubMed

    Mohamad, Shwan; Khan, Imran; Hey, S Y; Hussain, S S Musheer

    2016-03-01

    A systematic review to study the skin complications associated with the bone-anchored hearing aid in relation to surgical techniques. The following databases have been searched: MEDLINE, EMBASE, the Cochrane Library , Google scholar and the PubMed. The literature search date was from January 1977 until November 2013. Randomised controlled trials and retrospective studies were included. Initial search identified 420 publications. Thirty articles met the inclusion criteria of this review. The most common surgical techniques identified were full-thickness skin graft, Dermatome and linear incision techniques. The result shows that dermatome technique is associated with higher rate of skin complications when compared to linear incision and skin graft techniques. Based on the available literature, the use of a linear incision technique appears to be associated with lower skin complications; however, there is limited data available supporting this. Higher quality studies would allow a more reliable comparison between the surgical techniques. PMID:25503356

  19. Optimization of Lamb wave inspection techniques

    NASA Astrophysics Data System (ADS)

    Alleyne, David N.; Cawley, Peter

    Some problems associated with Lamb wave inspection techniques are briefly reviewed, and factors to be considered when selecting a practical Lamb wave inspection regime and ways to minimize possible problems are discussed. Tests on a butt-welded steel plate with simulated weld defects of different depths demonstrate that, operating below the a1 cut-off frequency with judicious selection of the testing technique, the presence of defects with depths around 30 percent of the plate thickness can be detected reliably from changes in the shape of the received waveform, The 2D Fourier transform method makes it possible to determine the amplitudes of the different propagating Lamb modes over the full frequency range of the input, yielding information which can be used for defect sizing.

  20. Optimizing ECM techniques against monopulse acquisition and tracking radars

    NASA Astrophysics Data System (ADS)

    Kwon, Ki Hoon

    1989-09-01

    Electronic countermeasure (ECM) techniques against monopulse radars, which are generally employed in the Surface-to-Air Missile targeting system, are presented and analyzed. Particularly, these ECM techniques are classified into five different categories, which are; denial jamming, deception jamming, passive countermeasures, decoys, and destructive countermeasures. The techniques are fully discussed. It was found difficult to quantize the jamming effectiveness of individual techniques, because ECM techniques are involved with several complex parameters and they are usually entangled together. Therefore, the methodological approach for optimizing ECM techniques is based on purely conceptual analysis of the techniques.

  1. The impact of surgical technique on neck dissection nodal yield: making a difference.

    PubMed

    Lörincz, Balazs B; Langwieder, Felix; Möckelmann, Nikolaus; Sehner, Susanne; Knecht, Rainald

    2016-05-01

    The nodal yield of neck dissections is an independent prognostic factor in several types of head and neck cancer. The authors aimed to determine whether the applied dissection technique has a significant impact on nodal yield. This is a single-institution, prospective study with internal control group (level of evidence: 2A). Data of 150 patients undergoing 223 neck dissections between February 2011 and March 2013 have been collected in a comprehensive cancer centre. Eighty-two patients underwent neck dissection with unwrapping the cervical fascia from lateral to medial, while 68 patients were operated without specifically unwrapping the fascia, in a caudal to cranial fashion. The standardised, horizontal neck dissection technique along the fascial planes resulted in a significantly higher nodal count in Levels I, II, III and IV, as well as in terms of overall nodal yield (mean: n = 22.53) than that of the vertical dissection applied in the control group (mean: n = 15.00). This is the first publication showing a direct correlation between neck dissection nodal yield and surgical technique. Therefore, it is paramount to optimise the applied surgical concept to maximise the oncological benefit. PMID:25784183

  2. Reconstruction of medial patello-femoral ligament: Comparison of two surgical techniques.

    PubMed

    Criscenti, G; De Maria, C; Sebastiani, E; Tei, M; Placella, G; Speziali, A; Vozzi, G; Cerulli, G

    2016-06-01

    The medial patello-femoral ligament is considered the most important passive patellar stabilizer and its proper functionality is essential for the patello-femoral joint stability. In this work, 18 human knees were randomly divided into two groups and reconstructed through two different surgical techniques: the "Through tunnel tendon" and the "Double converging tunnel" reconstructions. Subsequently, the samples were mechanically tested to evaluate the structural properties of reconstructed femur-MPFL-Patella complex (rFMPC). Particular attention was given to maintain the anatomical orientation between the patella and the graft. Both procedures showed lower stiffness and higher ultimate strain and absorbed energy compared to the native MPFL, but the advantages of the double converging tunnel technique are related to the restoration of the native MPFL sail-shape, to a better stress distribution on the patella, to the use of a single interference screw as fixation device and to the simplicity, rapidity and cost-effectivity of the surgical procedure. The evaluation of the structural properties of rMPFL is fundamental to evaluate the adequacy of the different techniques to restore the physiological structural properties of the native MPFL. PMID:26894660

  3. The Venetian blind technique: modification of the Pi procedure for the surgical correction of sagittal synostosis.

    PubMed

    Wexler, Andrew; Cahan, Leslie

    2012-11-01

    Numerous methods of surgical repair for scaphocephaly (sagittal synostosis) have been reported in the literature, from strip craniectomies to more complex methods of calvarial vault remodeling. While good cosmesis and restoration of a normal anteroposterior diameter may be obtained with these methods, a more rounded contour of the biparietal areas is often more difficult to achieve. We describe a modification of the Pi technique, described by Jane in 1976, that results in a more rounded contour of the biparietal areas. We report our experience on cranial vault remodeling for the correction of scaphocephaly in 51 patients from 1998 to 2011. PMID:23154346

  4. Novel techniques for the surgical management of abdominopelvic constriction rings in amniotic band syndrome.

    PubMed

    Capone, Avery C; Balasundaram, Naveen; Caouette-Laberge, Louise; Papay, Frank A; Lucas, Armand R; Seifarth, Federico G; Doumit, Gaby D

    2015-02-01

    Constriction rings are associated with amniotic band syndrome and most often present in the extremities. Constriction bands of the trunk are rare, and a standard of surgical care remains elusive. Traditional methods of constriction ring excision rely on soft-tissue rearrangement with multiple Z-plasties, but renewed interest in linear closure and limited Z-plasty has emerged. The authors review contemporary literature and report two cases of abdominopelvic constriction ring reconstruction with long-term follow-up. Novel techniques including anterior sheath Y-V plasty, pteruges release of the Scarpa fascia, and limited Z-plasty closure may minimize the need for serrated scar patterns. PMID:25626800

  5. Lateralization of the inferior alveolar nerve with simultaneous implant placement: surgical techniques.

    PubMed

    Garg, A K; Morales, M J

    1998-01-01

    In the event of moderate to severe mandibular bone resorption posterior to the mental foramen, repositioning of the inferior alveolar nerve provides a greater amount of available bone for implant placement and reduces the risk of nerve injury. While neural paresthesia may initially occur, this altered sensation generally resolves spontaneously. Alveolar nerve repositioning may be possible in cases in which other procedures cannot be performed due to the extent of atrophy of the posterior mandibular alveolar crest. This article presents the surgical technique to achieve this objective. PMID:10093565

  6. Peroneal Tenodesis With the Use of Tendoscopy: Surgical Technique and Report of 1 Case

    PubMed Central

    Mattos e Dinato, Mauro Cesar; de Faria Freitas, Marcio; Pereira Filho, Miguel Viana

    2014-01-01

    Peroneus brevis tendon injury is the most common lesion of the peroneal tendons. The initial treatment is conservative, and surgical treatment is indicated if conservative treatment fails. It is often necessary to open the entire upper and lower retinaculum to obtain adequate visualization of the structures. We present a case in which the peroneus brevis tenodesis was used with the aid of tendoscopy. This technique should be used for patients with lesions affecting more than 50% of the tendon diameter. We found that, by making small incisions, the patient recovered well, quickly, with resolution of pain. PMID:24749027

  7. Case Report: ALCAPA syndrome: successful repair with an anatomical and physiological alternative surgical technique.

    PubMed

    Vilá Mollinedo, Luis Gustavo; Jaime Uribe, Andrés; Aceves Chimal, José Luis; Martínez-Rubio, Roberto Pablo; Hernández-Romero, Karen Patricia

    2016-01-01

    Anomalous left coronary artery from the pulmonary artery, or ALCAPA syndrome, is a rare congenital cardiac disease that can cause myocardial infarction, heart failure and even death in paediatric patients. Only few untreated patients survive until adult age. Here we present the case of a 33-year-old female patient with paroxysmal tachycardia, syncope and mild exertional dyspnoea. She was diagnosed with ALCAPA syndrome and underwent surgical correction with an alternative technique of left main coronary artery extension to the aorta. PMID:27547381

  8. Case Report: ALCAPA syndrome: successful repair with an anatomical and physiological alternative surgical technique

    PubMed Central

    Vilá Mollinedo, Luis Gustavo; Jaime Uribe, Andrés; Aceves Chimal, José Luis; Martínez-Rubio, Roberto Pablo; Hernández-Romero, Karen Patricia

    2016-01-01

    Anomalous left coronary artery from the pulmonary artery, or ALCAPA syndrome, is a rare congenital cardiac disease that can cause myocardial infarction, heart failure and even death in paediatric patients. Only few untreated patients survive until adult age. Here we present the case of a 33-year-old female patient with paroxysmal tachycardia, syncope and mild exertional dyspnoea. She was diagnosed with ALCAPA syndrome and underwent surgical correction with an alternative technique of left main coronary artery extension to the aorta. PMID:27547381

  9. Racial and ethnic disparities in gastric cancer outcomes: More important than surgical technique?

    PubMed Central

    Merchant, Shaila J; Li, Lily; Kim, Joseph

    2014-01-01

    Racial and ethnic disparities in cancer care are major public health concerns and their identification is necessary to develop interventions to eliminate these disparities. We and others have previously observed marked disparities in gastric cancer outcomes between Eastern and Western patients. These disparities have long been attributed to surgical technique and extent of lymphadenectomy. However, more recent evidence suggests that other factors such as tumor biology, environmental factors such as Helicobacter pylori infection and stage migration may also significantly contribute to these observed disparities. We review the literature surrounding disparities in gastric cancer and provide data pertaining to potential contributing factors. PMID:25206261

  10. Minimally Invasive Surgical Technique in Periodontal Regeneration: A Randomized Controlled Clinical Trial Pilot Study.

    PubMed

    Ghezzi, Carlo; Ferrantino, Luca; Bernardini, Luigi; Lencioni, Margherita; Masiero, Silvia

    2016-01-01

    The purpose of this study was to compare two minimally invasive surgical techniques (MISTs) for the treatment of periodontal defects: (1) guided tissue regeneration (GTR) using resorbable minimembrane and particulate xenograft (DBBM); and (2) inductive periodontal regeneration (IPR) using enamel matrix derivatives and DBBM. A sample of 20 infrabony periodontal defects in 20 patients were randomly assigned to either the GTR or the IPR group. A follow-up was performed at 12 months postoperative. Significant improvement in clinical parameters was observed in both groups, although no intergroup differences were found. MIST with GTR or IPR demonstrated very good outcomes 1 year after surgery, with no differences between treatment groups. PMID:27333004

  11. A Review of Current Concepts in Flexor Tendon Repair: Physiology, Biomechanics, Surgical Technique and Rehabilitation.

    PubMed

    Singh, Rohit; Rymer, Ben; Theobald, Peter; Thomas, Peter B M

    2015-12-28

    Historically, the surgical treatment of flexor tendon injuries has always been associated with controversy. It was not until 1967, when the paper entitled Primary repair of flexor tendons in no man's land was presented at the American Society of Hand Surgery, which reported excellent results and catalyzed the implementation of this technique into worldwide practice. We present an up to date literature review using PubMed and Google Scholar where the terms flexor tendon, repair and rehabilitation were used. Topics covered included functional anatomy, nutrition, biome-chanics, suture repair, repair site gapping, and rehabilitation. This article aims to provide a comprehensive and complete overview of flexor tendon repairs. PMID:26793293

  12. Evaluation of a training course on open vascular surgical techniques in aortoiliac pathology - 5 years of experience

    PubMed Central

    STANCU, BOGDAN; BETEG, FLORIN; MIRONIUC, AUREL; MUSTE, AUREL; GHERMAN, CLAUDIA

    2015-01-01

    Introduction The aim of this prospective study was to assess the efficacy of a vascular surgery course (2008–2012), and to verify the viability and the feasibility of vascular anastomoses. Material and method The vascular surgical techniques performed simultaneously on pigs were: enlargement prosthetic angioplasty, abdominal aortic interposition graft and aortoiliac bypass. The endpoints of the study were the surgical skills and the technical quality, assessed on a scale ranging from 1 (satisfactory) to 3 (very good) for our participants. Results A significant improvement in vascular surgical skills tasks was observed during the study years and we also found a significant statistical association between the quality of the suture and the surgical technique used (Kendall coefficient=0.71, p=0.001<0.05). Conclusions Our course contributed to the improvement of the technical vascular surgical skills of the operator teams, reproducing in vivo, in pigs, the intraoperative environment of human patients. PMID:26528071

  13. Intradural Intramedullary Mixed Type Hemangioma: Optimizing the Surgical Management through Intraoperative Neurophysiological Monitoring

    PubMed Central

    Rahyussalim, Ahmad Jabir; Situmeang, Adrian; Safri, Ahmad Yanuar; Fadhly, Zulfa Indah K.

    2015-01-01

    Intradural intramedullary mixed type hemangioma is a rare histotype of primary spinal cord tumors, though it can carry a severe clinical burden leading to limb dysfunction or motor and sensory disturbances. Timely intervention with radical resection is the hallmark of treatment but achieving it is not an easy task even for experienced neurosurgeons. We herein present an exemplificative case presenting with sudden paraplegia in which total resection was achieved under intraoperative neurophysiology monitoring. A thorough discussion on the operative technique and the role of neuromonitoring in allowing a safe surgical management of primary spinal cord tumors is presented. PMID:26839729

  14. The analytical representation of viscoelastic material properties using optimization techniques

    NASA Technical Reports Server (NTRS)

    Hill, S. A.

    1993-01-01

    This report presents a technique to model viscoelastic material properties with a function of the form of the Prony series. Generally, the method employed to determine the function constants requires assuming values for the exponential constants of the function and then resolving the remaining constants through linear least-squares techniques. The technique presented here allows all the constants to be analytically determined through optimization techniques. This technique is employed in a computer program named PRONY and makes use of commercially available optimization tool developed by VMA Engineering, Inc. The PRONY program was utilized to compare the technique against previously determined models for solid rocket motor TP-H1148 propellant and V747-75 Viton fluoroelastomer. In both cases, the optimization technique generated functions that modeled the test data with at least an order of magnitude better correlation. This technique has demonstrated the capability to use small or large data sets and to use data sets that have uniformly or nonuniformly spaced data pairs. The reduction of experimental data to accurate mathematical models is a vital part of most scientific and engineering research. This technique of regression through optimization can be applied to other mathematical models that are difficult to fit to experimental data through traditional regression techniques.

  15. Optimal and suboptimal control technique for aircraft spin recovery

    NASA Technical Reports Server (NTRS)

    Young, J. W.

    1974-01-01

    An analytic investigation has been made of procedures for effecting recovery from equilibrium spin conditions for three assumed aircraft configurations. Three approaches which utilize conventional aerodynamic controls are investigated. Included are a constant control recovery mode, optimal recoveries, and a suboptimal control logic patterned after optimal recovery results. The optimal and suboptimal techniques are shown to yield a significant improvement in recovery performance over that attained by using a constant control recovery procedure.

  16. An investigation of optimization techniques for drawing computer graphics displays

    NASA Technical Reports Server (NTRS)

    Stocker, F. R.

    1979-01-01

    Techniques for reducing vector data plotting time are studied. The choice of tolerances in optimization and the application of optimization to plots produced on real time interactive display devices are discussed. All results are developed relative to plotting packages and support hardware so that results are useful in real world situations.

  17. Comparison of surgically induced astigmatism between one-handed and two-handed cataract surgery techniques

    PubMed Central

    Kawahara, Asushi; Kurosaka, Daijiro; Yoshida, Aktoshi

    2013-01-01

    Background The purpose of this study was to compare surgically induced astigmatism (SIA) between one-handed and two-handed cataract surgery techniques. Methods Eighty-eight eyes of 44 patients with no ocular disease other than cataract, who underwent cataract surgery by a single surgeon, were selected for this study. Cataract surgery was performed by coaxial phacoemulsification and intraocular lens implantation via a 2.4 mm transconjunctival single-plane sclerocorneal incision at the 12 o’clock position. In each patient, one eye was subjected to coaxial phacoemulsification using a one-handed technique while the fellow eye was subjected to coaxial phacoemulsification using a two-handed technique. For the two-handed technique, a corneal side port was created at the 2 o’clock position. The appropriate incision meridian was identified by a preoperative axis mark. SIA was calculated using the Alpins method. Results Mean SIA was 0.40 ± 0.28 diopters (D) in the one-handed technique group and 0.39 ± 0.25 D in the two-handed technique group. No statistically significant difference was found in the mean SIA score. The mean torque value was −0.05 ± 0.26 D in the one-handed technique group and 0.11 ± 0.37 D in the two-handed technique group. Mean torque was significantly lower (P<0.05) in the one-handed technique group than in the two-handed technique group. Conclusion The results indicate that the corneal side port in two-handed cataract surgery has a rotating effect on the axis of astigmatism. PMID:24124349

  18. The “excluding” suture technique for surgical closure of ventricular septal defects: A retrospective study comparing the standard technique

    PubMed Central

    Varghese, Roy; Saheed, Sanni; Ravi, Amrutha K; Sherrif, Ejaz Ahmed; Agarwal, Ravi; Kothandam, Sivakumar

    2016-01-01

    Background: Conventional methods of closure of ventricular septal defects involve placement of sutures 4-5 mm from the posterior inferior margin. This study compares the conventional method with an alternative technique wherein sutures are placed along the edge of the defect thereby “excluding” the conduction system and the tensor apparatus of the tricuspid valve from the suture line. Materials and Methods: Between January 2013 and January 2016, 409 consecutive patients were retrospectively reviewed and divided into two matched groups. Group A (n = 174) underwent closure using the alternative technique and Group B (n = 235) with the conventional technique. Patients with isolated ventricular septal defects (VSDs) (n = 136) were separately analyzed as were infants within this subset. Results: Immediate postoperative results were similar with no statistically significant differences in either group in terms of incidence of residual defects or postoperative tricuspid regurgitation. There was however a significantly increased incidence of post operative complete heart block (CHB) among patients in the conventional group (P = 0.02). Incidence of temporary heart block that reverted to sinus rhythm was also more in the conventional method group (Group B) (P = 0.03) as was right bundle branch block (P ≤ 0.05) in all the subsets of patients analyzed. Conclusion: Surgical closure of VSDs can be accomplished by placing sutures along the margins or away with comparable results. The incidence of CHB, however, seems to be less when the “excluding” technique is employed. PMID:27625520

  19. Comparison of two surgical techniques for the management of cervical spondylomyelopathy in dobermanns.

    PubMed

    Rusbridge, C; Wheeler, S J; Torrington, A M; Pead, M J; Carmichael, S

    1998-09-01

    A study was undertaken to compare the efficacy of two surgical techniques for the treatment of caudal cervical spondylomyelopathy (CCSM): ventral decompression (slot) and vertebral distraction and stabilisation with a screw and washer (screw/washer). Twenty-eight dobermanns managed surgically for disc-associated CCSM during a four-year period were studied retrospectively. The maximum postoperative period was 40 months. Cases were excluded if a minimum follow-up of 24 months after surgery could not be made. A 'slot' took a longer time to perform and had a higher rate of immediate postoperative deterioration. Duration of hospital stay was similar for both procedures. At six months after surgery the two techniques were comparable; 12/14 (screw/washer) and 13/14 (slot) patients were deemed to have a satisfactory outcome. Recurrence of cervical spinal cord disease was higher in the screw/washer dogs. At one year after surgery the recurrence rate was zero (slot) and 5/14 (screw/washer), respectively. At two years after surgery 4/14 of the slot dogs had deteriorated compared to 7/14 of the screw/washer dogs. Where investigated, the cause of deterioration was either a domino disc lesion or vertebral endplate collapse and dorsal displacement of the screw and washer. PMID:9791829

  20. Surgical techniques for smile restoration in patients with Möbius syndrome

    PubMed Central

    Ortiz-Rincones, María A.; Suárez-Gorrin, Fabiola

    2013-01-01

    Möbius syndrome is a congenital condition, the etiology when is not associated with misoprostol is not well defined. Signs and symptoms include difficulty swallowing, speech problems, drooling, strabismus, limitation of eye movement and more importantly, the facial blankness that these individuals have, result of the facial paralysis, due to atrophy of the cranial nerves that are involved in this condition. The ability to express emotions is affected and are considered “children without a smile.” There is currently no treatment to solvent the birth defects, the treatment options for reduce these alterations is the surgical option that has as main objective to restore muscle function through various techniques, used as required, the possibilities of applying them, is taking into consideration the outcome of the procedure to execute. Among the surgical techniques used mainly: the lengthening myoplasty of the temporal muscle,muscle transfers, cross-facial grafting, neurorrhaphy and nerve transposition, of which latter are the best performers, giving the patient a more natural, in as far as regards expression and function. Key words:Möbius syndrome, surgery, smile, facial nerve, muscle transfer, transfer nerve, temporalis muscle. PMID:24455082

  1. A variant technique for the surgical treatment of left ventricular aneurysms

    PubMed Central

    Evora, Paulo Roberto Barbosa; Tubino, Paulo Victor Alves; Gali, Luis Gustavo; Alves Junior, Lafaiete; Ferreira, Cesar Augusto; Bassetto, Solange; Menardi, Antônio Carlos; Rodrigues, Alfredo José; Vicente, Walter Vilella de Andrade

    2014-01-01

    Objective To present a surgical variant technique to repair left ventricular aneurysms. Methods After anesthesia, cardiopulmonary bypass, and myocardial protection with hyperkalemic tepic blood cardioplegia: 1) The left ventricle is opened through the infarct and an endocardial encircling suture is placed at the transitional zone between the scarred and normal tissue; 2) Next, the scar tissue is circumferentially plicated with deep stitches using the same suture thread, taking care to eliminate the entire septal scar; 3) Then, a second encircling suture is placed, completing the occlusion of the aneurysm, and; 4) Finally, the remaining scar tissue is oversewn with an invaginating suture, to ensure hemostasis. Myocardium revascularization is performed after correction of the left ventricle aneurysm. The same surgeon performed all the operations. Results Regarding the post-surgical outcome 4 patients (40%) had surgery 8 eight years ago, 2 patients (20%) were operated on over 6 years ago, and 1 patient (10%) was operated on more than 5 years ago. Three patients (30%) were in functional class I, class II in 2 patients (20%) and 2 patients (20%) with severe comorbidities remains in class III of the NYHA. There were three deaths (at four days, 15 days and eight months) in septuagenarians with acute myocardial infarction, diabetes and pulmonary emphysema. Conclusion The technique is easy to perform, safe and it can be an option for the correction of left ventricle aneurysms. PMID:25714220

  2. Laparoscopic vasectomy in African savannah elephant (Loxodonta africana); surgical technique and results.

    PubMed

    Marais, Hendrik J; Hendrickson, Dean A; Stetter, Mark; Zuba, Jeffery R; Penning, Mark; Siegal-Willott, Jess; Hardy, Christine

    2013-12-01

    Several small, enclosed reserves in southern Africa are experiencing significant elephant population growth, which has resulted in associated environmental damage and changes in biodiversity. Although several techniques exist to control elephant populations, e.g., culling, relocation, and immunocontraception, the technique of laparoscopic vasectomy of free-ranging bull elephants was investigated. Bilateral vasectomies were performed in 45 elephants. Of these elephants, one died within 24 hr of recovery and two had complications during surgery but recovered uneventfully. Histologic examination confirmed the resected tissue as ductus deferens in all the bulls. Most animals recovered uneventfully and showed no abnormal behavior after surgery. Complications recorded included incisional dehiscence, 1 full-thickness and 2 partial-thickness lacerations of the large intestine, and initial sling-associated complications, for example, deep radial nerve paresis. One bull was found dead 6 weeks after surgery without showing any prior abnormal signs. Vasectomy in free-ranging African bull elephants may be effectively performed in their normal environment. The surgical procedure can be used as a realistic population management tool in free-ranging elephants without major anesthetic, surgical, or postoperative complications. PMID:24437080

  3. Thirteen years follow-up of heart myxoma operated patients: what is the appropriate surgical technique?

    PubMed Central

    Siminelakis, Stavros; Kakourou, Alexandra; Batistatou, Alexandra; Sismanidis, Stelios; Ntoulia, Alexandra; Tsakiridis, Kosmas; Syminelaki, Theodora; Apostolakis, Eleftherios; Tsiouda, Theodora; Katsikogiannis, Nikolaos; Kougioumtzi, Ioanna; Dryllis, Georgios; Machairiotis, Nikolaos; Mpakas, Andreas; Beleveslis, Thomas; Zarogoulidis, Konstantinos

    2014-01-01

    Background Cardiac myxoma is a benign neoplasm that represents the most prevalent primary tumor of the heart. If not treated with the right surgical technique recurrence occurs. Aim of our study is to present our surgical approach and the histology of the tumors resected. Methods All patients, except for one, underwent extracorporeal circulation and mild hypothermia, right atrial or both atrial incision and excision of the fossa ovalis, followed by prosthetic patch suturing. All specimens were submitted for microscopic evaluation (haematoxylin-eosin). We contacted personally each patient and asked them to complete a standardized questionnaire, concerning their peri-operative characteristics. Results Six cases were “active” myxomas, 3 were “mildly active” and 3 were “inactive”. “Normal differentiation” was seen in 6, “medium” in 1 and “poor” in 5 cases. In our series there were no recurrences recorded during the follow-up period. Conclusions The ideal approach, according to our experience is right atrial or both atrial incision as described by Shumacker and King, with excision of the fossa ovalis and the surrounding tissues and closure with a pericardial patch. Such a technique provides an excellent long-term survival in these patients. PMID:24672697

  4. Surgical technique for transscleral fixation of a foldable posterior chamber intraocular lens.

    PubMed

    Yepez, Juan B; de Yepez, Jazmin Cedeño; Valero, Alejandro; Arevalo, J Fernando

    2006-01-01

    The safety and efficacy of a modified technique for transscleral fixation of a foldable posterior chamber intraocular lens (IOL) for intracapsular aphakia (secondary IOL) or after complicated phacoemulsification was evaluated. All eyes had inadequate or no posterior capsular support. Follow-up was between 4 and 26 months (mean, 12 months). Uncorrected visual acuity improved (> 2 lines) in all patients. During follow-up, the IOL was correctly positioned in all cases. There were no major complications, such as endophthalmitis or suture erosion through the conjunctiva at the site of fixation. No patient required further surgical interventions. This modified technique of transscleral fixation of foldable posterior chamber IOL offers the advantages of a small incision and rapid visual rehabilitation, and minimizes the risk of intraoperative and postoperative complications. PMID:16749265

  5. ARTHROSCOPIC RELEASE OF THE SUPRASCAPULAR NERVE: SURGICAL TECHNIQUE AND EVALUATION OF CLINICAL CASES

    PubMed Central

    Garcia Júnior, José Carlos; Paccola, Ana Maria Ferreira; Tonoli, Cristiane; Zabeu, José Luis Amin; Garcia, Jesely Pereira Myrrha

    2015-01-01

    To describe a specific surgical technique for arthroscopic decompression of the suprascapular nerve (SSN) and evaluate its preliminary results. Methods: Ten shoulders of nine patients were operated using a technique with portals differing from the already-known techniques, which did not use traction and made use of materials available within the public healthcare system. Results: Among the ten shoulders of nine patients, eight were right shoulders and two were left shoulders. The mean age was 69.5 years. The UCLA score increased from 11.7 to 26.1 points over the postoperative follow-up of 16.6 months. The SF-36 questionnaire score was 122.9 and the raw pain scale value was 88%. Conclusion: Arthroscopic decompression of the SSN in accordance with the described technique is reproducible and less traumatic than the open techniques. The patients achieved improvements in many of the parameters evaluated, particularly with regard to pain. Arthroscopic decompression of the SSN may be a therapeutic option for pathological compression of the SSN. PMID:27027028

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

    PubMed Central

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

    PubMed

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

    2013-12-31

    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

  8. Imaging equipment and techniques for optimal intraoperative imaging during endovascular interventions.

    PubMed

    Fillinger, M F; Weaver, J B

    1999-12-01

    Because endovascular procedures represent an ever-increasing portion of many vascular surgery practices, many surgeons are faced with difficult choices. Endovascular procedures often require open surgery, and open surgical techniques increasingly require fluoroscopic imaging. Without good intraoperative imaging, endovascular procedures are difficult and endovascular aneurysm repair is impossible. How does one balance the need for optimal imaging without sacrificing the ability to safely perform open surgical procedures, especially in the early stages of a developing endovascular program? Strategies include the use of a portable c-arm and carbon fiber table in the operating room (OR), adding a fixed imaging platform to an OR, gaining access to an angiography suite that does not meet OR requirements, and modifying it into an interventional suite that does meet operating room standards. Once the optimal equipment and facilities have been chosen, other choices must be considered. Should a radiology technician be hired? Should an interventional radiologist be available to assist or be incorporated as a routine member of the team? How will typical operating room procedures and technique need to be altered in an effort to optimize intraoperative imaging for endovascular procedures? This article gives an overview of the many issues that arise as a vascular surgery practice evolves to incorporate complex endovascular procedures. PMID:10651460

  9. Percutaneous Endoscopic Lumbar Foraminotomy: An Advanced Surgical Technique and Clinical Outcomes

    PubMed Central

    Oh, Hyun-Kyong; Kim, Ho; Lee, Sang-Ho; Lee, Haeng-Nam

    2014-01-01

    BACKGROUND: Although several authors have reported the use of endoscopic techniques to treat lumbar foraminal stenosis, the practical application of these techniques has been limited to soft disc herniation. OBJECTIVE: To describe the details of the percutaneous endoscopic lumbar foraminotomy (ELF) technique for bony foraminal stenosis and to demonstrate the clinical outcomes. METHODS: Two years of prospective data were collected from 33 consecutive patients with lumbar foraminal stenosis who underwent ELF. The surgical outcomes were assessed using the visual analog scale, Oswestry Disability Index, and modified MacNab criteria. The procedure begins at the safer extraforaminal zone rather than the riskier intraforaminal zone. Then, a full-scale foraminal decompression can be performed using a burr and punches under endoscopic control. RESULTS: The mean age of the 18 female and 15 male patients was 64.2 years. The mean visual analog scale score for leg pain improved from 8.36 at baseline to 3.36 at 6 weeks, 2.03 at 1 year, and 1.97 at 2 years post-surgery (P < .001). The mean Oswestry Disability Index improved from 65.8 at baseline to 31.6 at 6 weeks, 19.7 at 1 year, and 19.3 at 2 years post-surgery (P < .001). Based on the modified MacNab criteria, excellent or good results were obtained in 81.8% of the patients, and symptomatic improvements were obtained in 93.9%. CONCLUSION: Percutaneous ELF under local anesthesia could be an efficacious surgical procedure for the treatment of foraminal stenosis. This procedure may offer safe and reproducible results, especially for elderly or medically compromised patients. ABBREVIATIONS: ELF,endoscopic lumbar foraminotomy ODI, Oswestry Disability Index VAS, visual analog scale PMID:24691470

  10. True Percutaneous Transforaminal Lumbar Interbody Fusion: Case Illustrations, Surgical Technique, and Limitations.

    PubMed

    Syed, Hasan; Voyadzis, Jean-Marc

    2016-07-01

    Objective The last decade has seen significant advances in minimally invasive techniques for lumbar interbody fusion that have reduced approach-related morbidity. Percutaneous lumbar interbody fusion involves a posterior transforaminal approach to the disk space with a minimal access port through the Kambin triangle. This technique obviates the need for the facetectomy or laminectomy required in a traditional transforaminal approach. This article describes the surgical technique, potential advantages and limitations, and representative case illustrations. Methods Percutaneous transforaminal interbody fusion was performed on two patients with axial back and leg pain as a result of degenerative disk disease. Diskectomy and interbody cage insertion were completed through a tubular dilator placed onto the disk space in the Kambin triangle. Posterior fixation was achieved with percutaneous transfacet screws. Clinical outcome and postoperative complications are discussed. Results Both patients demonstrated significant clinical improvement after surgery with > 1 year follow-up despite experiencing transient neurologic symptoms. Conclusion Although this report demonstrates the feasibility and advantages of the approach, the technique is limited by the potential for nerve root injury and pseudoarthrosis. PMID:26291889

  11. [Surgical technique: reconstruction of deficient extensor apparatus of the knee - a case report].

    PubMed

    Wilken, F; Harrasser, N; Pohlig, F; Laux, F M; von Eisenhart-Rothe, R

    2015-04-01

    Injuries to the extensor apparatus of the knee are a rare but in case of their occurrence a serious injury. In the following discussion, the focus is on treatment of chronic patellar tendon tears. The aim of surgical treatment is the recovery of the active extension and full weight-bearing ability of the leg. The video presentation shows the operative treatment of a patient with a chronic extensor mechanism deficiency of the knee after multiple revision of a total knee arthroplasty due to periprosthetic infection and three-times occurrence of a patella tendon tear. A frame-shaped reinforcement between patella and tibial tuberosity by FiberTape® combined with a medial gastrocnemius flap was performed. This type of surgery is indicated in cases of large defects of the patellar tendon that cannot be treated with end-to-end suture or simple augmentation with autologous tendons (e.g. semitendinosus). In addition to augmentation of the tendon defect, cutaneous soft tissue defects around the knee and proximal lower leg can be covered. In general, the best treatment option is chosen according to size of the defect, the quality of the tendon tissue and possible previous surgery on the knee joint. There are no reports of large series of chronic patella tendon tears, but only isolated cases using a variety of techniques. In addition with low level of evidence, there is currently no established gold standard in the surgical treatment of insufficiencies of the extensor apparatus of the knee. PMID:25874403

  12. The utilization of six sigma and statistical process control techniques in surgical quality improvement.

    PubMed

    Sedlack, Jeffrey D

    2010-01-01

    Surgeons have been slow to incorporate industrial reliability techniques. Process control methods were applied to surgeon waiting time between cases, and to length of stay (LOS) after colon surgery. Waiting times between surgeries were evaluated by auditing the operating room records of a single hospital over a 1-month period. The medical records of 628 patients undergoing colon surgery over a 5-year period were reviewed. The average surgeon wait time between cases was 53 min, and the busiest surgeon spent 291/2 hr in 1 month waiting between surgeries. Process control charting demonstrated poor overall control of the room turnover process. Average LOS after colon resection also demonstrated very poor control. Mean LOS was 10 days. Weibull's conditional analysis revealed a conditional LOS of 9.83 days. Serious process management problems were identified in both analyses. These process issues are both expensive and adversely affect the quality of service offered by the institution. Process control mechanisms were suggested or implemented to improve these surgical processes. Industrial reliability and quality management tools can easily and effectively identify process control problems that occur on surgical services. PMID:20946422

  13. Triceps fascial tongue exposure for total elbow arthroplasty: surgical technique and case series.

    PubMed

    Marinello, Patrick G; Peers, Sebastian; Styron, Joseph; Pervaiz, Khurram; Evans, Peter J

    2015-06-01

    During a posterior approach to the elbow, the triceps muscle body and tendon insertion must be addressed during exposure. Several methods exist including performing an olecranon osteotomy. The triceps fascial tongue exposure, originally described by Van Gorder in 1940, provides an excellent view of the joint while causing minimal trauma to the extensor mechanism facilitating tendon healing, and easy intraoperative conversion from fracture fixation to a total elbow arthroplasty if a fracture is not able to be reconstructed. Using a standard posterior approach to the elbow, a triceps tongue is created. A distally based flap of the triceps tendon approximately 10 cm long and 2 to 3 cm wide is created and a remnant of the tendon is kept on all sides to secure a meticulous repair with nonabsorbable figure-of-eight sutures at the conclusion of the case. In our case series, 29 patients underwent 30 total elbow arthroplasties. There were no triceps-related failures. This surgical technique is a useful alternative surgical exposure to the posterior elbow for fractures and arthroplasty. PMID:25929418

  14. Open versus Laparoscopic Surgery: Does the Surgical Technique Influence Pain Outcome? Results from an International Registry

    PubMed Central

    Allvin, Renée; Rawal, Narinder; Johanzon, Eva; Bäckström, Ragnar

    2016-01-01

    Postoperative pain management relevant for specific surgical procedures is debated. The importance of evaluating pain with consideration given to type of surgery and the patient's perspective has been emphasized. In this prospective cohort study, we analysed outcome data from 607 patients in the international PAIN OUT registry for assessment and comparison of postoperative pain outcome within the 24 first hours after laparoscopic and open colonic surgery. Patients from the laparoscopic group scored minimum pain at a higher level than the open group (P = 0.012). Apart from minimum pain, no other significant differences in patient reported outcomes were observed. Maximum pain scores >3 were reported from 77% (laparoscopic) and 68% (open) patients (mean ≥ 5 in both groups). Pain interference with mobilization was reported by 87–93% of patients. Both groups scored high levels of patient satisfaction. In the open group, a higher frequency of patients received a combination of general and regional anaesthesia, which had an impact of the minimum pain score. Our results from registry data indicate that surgical technique does not influence the quality of postoperative pain management during the first postoperative day if adequate analgesia is given. PMID:27127649

  15. Using optimization models to demonstrate the need for structural changes in training programs for surgical medical residents.

    PubMed

    Turner, Jonathan; Kim, Kibaek; Mehrotra, Sanjay; DaRosa, Debra A; Daskin, Mark S; Rodriguez, Heron E

    2013-09-01

    The primary goal of a residency program is to prepare trainees for unsupervised care. Duty hour restrictions imposed throughout the prior decade require that residents work significantly fewer hours. Moreover, various stakeholders (e.g. the hospital, mentors, other residents, educators, and patients) require them to prioritize very different activities, often conflicting with their learning goals. Surgical residents' learning goals include providing continuity throughout a patient's pre-, peri-, and post-operative care as well as achieving sufficient surgical experience levels in various procedure types and participating in various formal educational activities, among other things. To complicate matters, senior residents often compete with other residents for surgical experience. This paper features experiments using an optimization model and a real dataset. The experiments test the viability of achieving the above goals at a major academic center using existing models of delivering medical education and training to surgical residents. It develops a detailed multi-objective, two-stage stochastic optimization model with anticipatory capabilities solved over a rolling time horizon. A novel feature of the models is the incorporation of learning curve theory in the objection function. Using a deterministic version of the model, we identify bounds on the achievement of learning goals under existing training paradigms. The computational results highlight the structural problems in the current surgical resident educational system. These results further corroborate earlier findings and suggest an educational system redesign is necessary for surgical medical residents. PMID:23519945

  16. Surgical resection technique of a fused supernumerary lateral incisor: a clinical report and review of the literature.

    PubMed

    Beier, Ulrike Stephanie; Dumfahrt, Herbert; Widmann, Gerlig; Puelacher, Wolfgang

    2012-01-01

    This case report presents the surgical and restorative management of a fused supernumerary left lateral incisor. The diagnosis was confirmed using conventional radiographs and CT. The case report discusses the value of CT for evaluation of the root relationships and describes the varied morphology associated with supernumerary incisors, the surgical resection technique, partial pulpotomy, and restoration with composite resin after mechanical exposure of the remaining tooth's pulp. PMID:22782063

  17. Optimizing integration of electrosurgical hand controls within a laparoscopic surgical tool.

    PubMed

    Rousek, Justin B; Brown-Clerk, Bernadette; Lowndes, Bethany R; Balogh, Bradley J; Hallbeck, M Susan

    2012-05-01

    Abstract In laparoscopic surgery, electrosurgical equipment is operated by means of one or more foot pedals positioned on the floor in front of the surgeon causing poor ergonomic posture and physical discomfort. The focus of this study was to ergonomically explore the integration of electrosurgical hand controls within the previously designed Intuitool™ laparoscopic surgical instrument to optimize functionality. Three different hand control designs (CDs) were implemented within the Intuitool™ and each CD contained the standard cutting and coagulation features, previously operated by foot pedals. This study used 26 right-handed participants, with no previous laparoscopic surgery experience. The participants completed simple tasks using all three CDs within a simulated abdomen. Electromyography (EMG) sensors and force sense resistors (FSRs) were utilized to measure muscle activity and button actuation force, respectively. A questionnaire was also utilized to measure comfort level of each CD. The results indicated that the close proximity of CD 1 generated greater actuation force for all tasks, was rated easier to use (P = 0.003) and was preferred more frequently by the participants (53.8%) compared to CD 2 and 3. As a result, CD 1 was determined to be an optimal ergonomic design for electrosurgical hand controls within the Intuitool™. PMID:21919825

  18. "Modified Adductor Sling Technique"- a surgical therapy for patellar instability in children and adolescents

    PubMed Central

    Alm, Lena; Frosch, Karl-Heinz; Preiss, Achim; Heitmann, Maximilian; Akoto, Ralph

    2016-01-01

    Aims and Objectives: Due to open femoral physis, the therapy of patellar instability in children and adolescents is challenging. We developed a surgical technique, modified form of the "Adductor-Sling-Technique" by Sillanpää which offers a surgical treatment to avoid damage to the femoral physis. The purpose of this study is to determine whether there is a benefit in the clinical outcome for patients operated by the "modified Adductor Sling Technique" in comparison to patients with other surgical procedures. Materials and Methods: Twenty "modified Adductor Sling" reconstructions in 19 patients (age 11-24) were included in the study until now, 15 patients with open physis and 4 patients with closed physis with special indications. Since 2010 "modified Adductor Sling" reconstruction was performed by looping the gracilis tendon around the adductor magnus tendon and attaching it at the medial facette of the patella. Clinical outcome was retrospectively evaluated at a mean follow-up period of 1.3 years (range 0.5-3.6). The evaluation also included Lysholm Score, Kujala Score and DGU score. Statistical analysis was performed using IBM®SPSS®Statistics Version 21. A P value less than 0.5 was considered significant. Results: The average age at the time of operation was 14.9 years (range 11.2-24.3). Recurrent dislocation occurred in 4 out of 20 cases (20%). It was noticeable that out of those 4 patients 2 patients had a lateral release in addition to the "modified Adductor Sling Technique" due to lateral hyperpression. No other patients had a lateral release in our patient population. Also, out of those 4 patients 3 patients had an additional maltracking of the patella, caused by a high TTTG, severe trochlea dysplasia or additional axial deformity. The overall Kujala Score was 87 (range 46-100) points, in patients without re-dislocation it was 94 (range 46-100) points. The overall Lysholm Score was 85 (range 39-100) points, in the group without re-dislocation 90 (range

  19. A Modified Particle Swarm Optimization Technique for Finding Optimal Designs for Mixture Models.

    PubMed

    Wong, Weng Kee; Chen, Ray-Bing; Huang, Chien-Chih; Wang, Weichung

    2015-01-01

    Particle Swarm Optimization (PSO) is a meta-heuristic algorithm that has been shown to be successful in solving a wide variety of real and complicated optimization problems in engineering and computer science. This paper introduces a projection based PSO technique, named ProjPSO, to efficiently find different types of optimal designs, or nearly optimal designs, for mixture models with and without constraints on the components, and also for related models, like the log contrast models. We also compare the modified PSO performance with Fedorov's algorithm, a popular algorithm used to generate optimal designs, Cocktail algorithm, and the recent algorithm proposed by [1]. PMID:26091237

  20. A Modified Particle Swarm Optimization Technique for Finding Optimal Designs for Mixture Models

    PubMed Central

    Wong, Weng Kee; Chen, Ray-Bing; Huang, Chien-Chih; Wang, Weichung

    2015-01-01

    Particle Swarm Optimization (PSO) is a meta-heuristic algorithm that has been shown to be successful in solving a wide variety of real and complicated optimization problems in engineering and computer science. This paper introduces a projection based PSO technique, named ProjPSO, to efficiently find different types of optimal designs, or nearly optimal designs, for mixture models with and without constraints on the components, and also for related models, like the log contrast models. We also compare the modified PSO performance with Fedorov's algorithm, a popular algorithm used to generate optimal designs, Cocktail algorithm, and the recent algorithm proposed by [1]. PMID:26091237

  1. A Review of Current Concepts in Flexor Tendon Repair: Physiology, Biomechanics, Surgical Technique and Rehabilitation

    PubMed Central

    Rymer, Ben; Theobald, Peter; Thomas, Peter B.M.

    2015-01-01

    Historically, the surgical treatment of flexor tendon injuries has always been associated with controversy. It was not until 1967, when the paper entitled Primary repair of flexor tendons in no man’s land was presented at the American Society of Hand Surgery, which reported excellent results and catalyzed the implementation of this technique into worldwide practice. We present an up to date literature review using PubMed and Google Scholar where the terms flexor tendon, repair and rehabilitation were used. Topics covered included functional anatomy, nutrition, biome-chanics, suture repair, repair site gapping, and rehabilitation. This article aims to provide a comprehensive and complete overview of flexor tendon repairs. PMID:26793293

  2. [Surgical Techniques for Patella Replacement in Cases of Deficient Bone Stock in Revision TKA].

    PubMed

    Ritschl, P; Machacek, F; Strehn, L; Kloiber, J

    2015-06-01

    The patella replacement in revision surgery is a challenge especially in cases of unsufficient bone stock. Depending on the extent of the bone defect, the following videos demonstrate different approaches: Video 1: bone sparing removal of the patella implant: onlay-type patella implants. Video 2: complete cortical bone rim of the patella, residual thickness between 6 to 10 mm: biconvex patella implant. Video 3 and 4: small defects of the cortical bone rim of the patella, residual thickness 1 to 5 mm (patella shell): gull-wing osteotomy, patella bone grafting techniques. Video 5: partial necrosis/defect of the patella shell with incomplete cortical bone rim: porous tantalum patella prosthesis. On account of the various surgical options for different bone defects of the patella, patellectomy and pure patelloplasty should be avoided to prevent functional shortcomings. PMID:26114564

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

    PubMed Central

    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

  4. Process sequence optimization for digital microfluidic integration using EWOD technique

    NASA Astrophysics Data System (ADS)

    Yadav, Supriya; Joyce, Robin; Sharma, Akash Kumar; Sharma, Himani; Sharma, Niti Nipun; Varghese, Soney; Akhtar, Jamil

    2016-04-01

    Micro/nano-fluidic MEMS biosensors are the devices that detects the biomolecules. The emerging micro/nano-fluidic devices provide high throughput and high repeatability with very low response time and reduced device cost as compared to traditional devices. This article presents the experimental details for process sequence optimization of digital microfluidics (DMF) using "electrowetting-on-dielectric" (EWOD). Stress free thick film deposition of silicon dioxide using PECVD and subsequent process for EWOD techniques have been optimized in this work.

  5. Application of optimization techniques to vehicle design: A review

    NASA Technical Reports Server (NTRS)

    Prasad, B.; Magee, C. L.

    1984-01-01

    The work that has been done in the last decade or so in the application of optimization techniques to vehicle design is discussed. Much of the work reviewed deals with the design of body or suspension (chassis) components for reduced weight. Also reviewed are studies dealing with system optimization problems for improved functional performance, such as ride or handling. In reviewing the work on the use of optimization techniques, one notes the transition from the rare mention of the methods in the 70's to an increased effort in the early 80's. Efficient and convenient optimization and analysis tools still need to be developed so that they can be regularly applied in the early design stage of the vehicle development cycle to be most effective. Based on the reported applications, an attempt is made to assess the potential for automotive application of optimization techniques. The major issue involved remains the creation of quantifiable means of analysis to be used in vehicle design. The conventional process of vehicle design still contains much experience-based input because it has not yet proven possible to quantify all important constraints. This restraint on the part of the analysis will continue to be a major limiting factor in application of optimization to vehicle design.

  6. Effect of Opiates, Anesthetic Techniques, and Other Perioperative Factors on Surgical Cancer Patients

    PubMed Central

    Kaye, Alan David; Patel, Nayan; Bueno, Franklin Rivera; Hymel, Brad; Vadivelu, Nalini; Kodumudi, Gopal; Urman, Richard D.

    2014-01-01

    Background Opioid pharmacotherapy is often used to treat cancer pain. However, morphine and other opioid-like substance use in patients with cancer may have significant adverse consequences, including the suppression of both innate and acquired immune responses. Although studies have examined the possibility that regional anesthesia attenuates the immunosuppressive response of surgery, the effects of morphine and other opioid-related substances on tumor progression remain unknown. Methods This article presents an evidence-based review of the influence of opioids and anesthetic technique on the immune system in the context of cancer recurrence. The review focuses on the field of regional anesthesia and the setting of surgical oncologic procedures. The method for perioperative pain management and the technique of anesthesia chosen for patients in cancer surgery were explored. Results General anesthetics have been indicated to suppress both cell-mediated immunity and humoral immunity. Evidence suggests that intravenous opioids suppress the immune system. However, the mechanisms by which anesthetics and analgesics inhibit the immune system are not understood. Compared with the alternatives, regional analgesia offers reduced blood loss and superior postoperative analgesia. Because of these advantages, the use of regional analgesia has increased in oncologic surgeries. Conclusion Immune responses from all components of the immune system, including both the humoral and cell-mediated components, appear to be suppressed by anesthetics and analgesics. The clinical anesthesiologist should consider these factors in the application of technique, especially in cancer surgery. PMID:24940132

  7. Enhanced Multiobjective Optimization Technique for Comprehensive Aerospace Design. Part A

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Aditi; Rajadas, John N.

    1997-01-01

    A multidisciplinary design optimization procedure which couples formal multiobjectives based techniques and complex analysis procedures (such as computational fluid dynamics (CFD) codes) developed. The procedure has been demonstrated on a specific high speed flow application involving aerodynamics and acoustics (sonic boom minimization). In order to account for multiple design objectives arising from complex performance requirements, multiobjective formulation techniques are used to formulate the optimization problem. Techniques to enhance the existing Kreisselmeier-Steinhauser (K-S) function multiobjective formulation approach have been developed. The K-S function procedure used in the proposed work transforms a constrained multiple objective functions problem into an unconstrained problem which then is solved using the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. Weight factors are introduced during the transformation process to each objective function. This enhanced procedure will provide the designer the capability to emphasize specific design objectives during the optimization process. The demonstration of the procedure utilizes a computational Fluid dynamics (CFD) code which solves the three-dimensional parabolized Navier-Stokes (PNS) equations for the flow field along with an appropriate sonic boom evaluation procedure thus introducing both aerodynamic performance as well as sonic boom as the design objectives to be optimized simultaneously. Sensitivity analysis is performed using a discrete differentiation approach. An approximation technique has been used within the optimizer to improve the overall computational efficiency of the procedure in order to make it suitable for design applications in an industrial setting.

  8. Surgical Technique for Repair of Peripheral Pulmonary Artery Stenosis and Other Complex Peripheral Reconstructions.

    PubMed

    Mainwaring, Richard D; Ibrahimiye, Ali N; Hanley, Frank L

    2016-08-01

    Surgical reconstruction of peripheral pulmonary artery stenosis is a technically challenging procedure due to the need to access all lobar and segmental branches. This paper describes our surgical approach that entails division of the main pulmonary and separation of the branch pulmonary arteries. This surgical approach can also be utilized for other complex peripheral pulmonary artery reconstructions. PMID:27449462

  9. Stochastic optimization techniques for NDE of bridges using vibration signatures

    NASA Astrophysics Data System (ADS)

    Yi, Jin-Hak; Feng, Maria Q.

    2003-08-01

    A baseline model updating is the first step for the model-based non destructive evaluation for civil infrastructures. Many researches have been drawn to obtain a more reliable baseline model. In this study, heuristic optimization techniques (or called as stochastic optimization techniques) including the genetic algorithm, the simulated annealing, and the tabu search, were have been investigated for constructing the reliable baseline model for an instrumented new highway bridge, and also were compared with the result of conventional sensitivity method. The preliminary finite element model of the bridge was successfully updated to a baseline model based on measured vibration data.

  10. Surgical Fixation of Sternal Fractures: Preoperative Planning and a Safe Surgical Technique Using Locked Titanium Plates and Depth Limited Drilling

    PubMed Central

    Schulz-Drost, Stefan; Oppel, Pascal; Grupp, Sina; Schmitt, Sonja; Carbon, Roman Th.; Mauerer, Andreas; Hennig, Friedrich F.; Buder, Thomas

    2015-01-01

    Different ways to stabilize a sternal fracture are described in literature. Respecting different mechanisms of trauma such as the direct impact to the anterior chest wall or the flexion-compression injury of the trunk, there is a need to retain each sternal fragment in the correct position while neutralizing shearing forces to the sternum. Anterior sternal plating provides the best stability and is therefore increasingly used in most cases. However, many surgeons are reluctant to perform sternal osteosynthesis due to possible complications such as difficulties in preoperative planning, severe injuries to mediastinal organs, or failure of the performed method. This manuscript describes one possible safe way to stabilize different types of sternal fractures in a step by step guidance for anterior sternal plating using low profile locking titanium plates. Before surgical treatment, a detailed survey of the patient and a three dimensional reconstructed computed tomography is taken out to get detailed information of the fracture’s morphology. The surgical approach is usually a midline incision. Its position can be described by measuring the distance from upper sternal edge to the fracture and its length can be approximated by the summation of 60 mm for the basis incision, the thickness of presternal soft tissue and the greatest distance between the fragments in case of multiple fractures. Performing subperiosteal dissection along the sternum while reducing the fracture, using depth limited drilling, and fixing the plates prevents injuries to mediastinal organs and vessels. Transverse fractures and oblique fractures at the corpus sterni are plated longitudinally, whereas oblique fractures of manubrium, sternocostal separation and any longitudinally fracture needs to be stabilized by a transverse plate from rib to sternum to rib. Usually the high convenience of a patient is seen during follow up as well as a precise reconstruction of the sternal morphology. PMID

  11. RADIOGRAPHIC ABNORMALITIES OF THE TALUS IN PATIENTS WITH CLUBFOOT AFTER SURGICAL RELEASE USING THE MCKAY TECHNIQUE

    PubMed Central

    Pinto, José Antonio; Hernandes, Andréa Canizares; Buchaim, Thais Paula; Blumetti, Francesco Camara; Chertman, Carla; Yamane, Patrícia Corey; da Rocha Corrêa Fernandes, Artur

    2015-01-01

    Objective: To analyze morphological abnormalities of the talus in patients with clubfoot after surgical treatment using the McKay technique. Method: Lateral standing-position radiographs of the feet of 14 patients with unilateral clubfoot who underwent treatment by means of the doubleincision McKay technique were retrospectively analyzed. All the patients were operated by the same surgeon, with an average of 6.53 years between surgery and the radiograph. We compared the radiographic characteristics of the talus between the operated and the contralateral foot. We assessed the presence of deformity of the talar dome and head (sphericity evaluation); the talar length and height; the percentage and degree of navicular subluxation; abnormalities of the Gissane angle; and the trabecular bone pattern. Results: Abnormalities of the talar head occurred in 92.8% of the patients; of the talar dome in 92.8%; and of the trabecular pattern in 100%. The talar length ratio between the operated and the contralateral foot ranged from 0.61 to 0.88 (mean 0.79; SD = 0.09), while the height ratio ranged from 0.57 to 0.98 (mean 0.82; SD = 0.12). The Gissane angle was greater in all of the operated feet, and all of them also showed navicular subluxation, at a rate ranging from 6.43 to 59.75% (mean 26.34%; SD = 16.66%). Conclusion: Talar abnormalities occurred in 100% of the feet treated using the McKay technique. It was shown that establishing radiographic parameters to describe and quantify these deformities was feasible, through simple and easy-to-perform techniques. PMID:27047821

  12. Efficiency of Various Cerebral Protection Techniques Used during the Surgical Treatment of Chronic Pulmonary Thromboembolism

    PubMed Central

    Kamenskaya, Oksana Vasilyevna; Cherniavsky, Alexander Mikhailovich; Klinkova, Asya Stanislavovna; Cherniavsky, Mikhail Alexandrovich; Meshkov, Ivan Olegovich; Lomivorotov, Vladimir Vladimirovich; Kornilov, Igor Anatolyevich; Karaskov, Alexander Mikhailovich

    2015-01-01

    Abstract: Circulatory arrest during pulmonary thromboendarterectomy (PTE) for chronic pulmonary embolism leads to an increased risk of cerebral ischemia and neurological complications. This study aimed to assess the efficacy of various cerebral protection techniques used during the surgical treatment of chronic pulmonary thromboembolism. We prospectively studied 61 patients with chronic pulmonary thromboembolism who underwent PTE. We compared the dynamics of cerebral oxygen saturation (rSO2, %) during the surgical treatment and analyzed neurological complications during the early postoperative period in two groups of patients: 30 patients who underwent surgery under conditions of moderate hypothermia (23°C–24°C) combined with antegrade unilateral cerebral perfusion (ACP group) and 31 patients who underwent thromboendarterectomy under deep hypothermic circulatory arrest (18°C, DHCA group) combined with craniocerebral hypothermia. In the ACP group, regional rSO2 decreased by less than 20% from baseline during the course of PTE. In the DHCA group, a more profound reduction of cerebral oxygen supply (by >30% from baseline) was recorded compared with the ACP group (p < .05). During the early postoperative period, 29% of patients in the DHCA group exhibited neurological complications, compared with only 7% of patients from the ACP group. The results of logistic regression analysis indicated that the risk of progressive neurological deficit depended on the duration of the intraoperative period when the absolute values of regional rSO2 were <40%. The method with the best adjustment to human physiology in patients with chronic pulmonary thromboembolism was antegrade cerebral perfusion. This method provides a smaller decrease in cerebral oxygen supply during thromboendarterectomy and significantly reduces the risk of ischemia and neurological complications in the early postoperative period. PMID:26405357

  13. ‘Minimum-incision’ endoscopically assisted transvesical prostatectomy: Surgical technique and early outcomes

    PubMed Central

    El-Karamany, Tarek M.; Al-Adl, Ahmed M.; Abdel-Baky, Shabieb A.; Abdel-Azeem, Abdallah F.; Zaazaa, Mohamed A.

    2014-01-01

    Objective To describe the surgical technique and report the early outcomes of a ‘minimum-incision’ endoscopically assisted transvesical prostatectomy (MEATP) for managing benign prostatic obstruction secondary to a large (>80 g) prostate. Patients and methods In a prospective feasibility trial, 60 men with large benign prostates underwent MEATP. The baseline and postoperative evaluation included the International Prostate Symptom Score (IPSS), a measurement of maximum urinary flow rate (Qmax), and the postvoid residual (PVR) urine volume. The adenoma was enucleated digitally through a 3-cm suprapubic skin incision, and haemostasis was completed with endoscopic coagulation of the prostatic fossa. Perioperative complications were recorded and stratified according to the modified Clavien–Dindo score. Results The mean (SD, range) prostate weight estimated by ultrasonography was 102.9 (15.4, 80–160) g, the operative duration was 52 (8, 40–65) min, the haemoglobin loss was 2.1 (1, 0.4–5) g/dL, the catheterisation time was 5.2 (1.3, 4–9) days, and the hospital stay was 6.2 (1.4, 5–10) days. There were 21 complications recorded in 16 (27%) patients, and most (86%) were of grades 1 and 2. The most frequent complications were bleeding requiring a blood transfusion (8%), and prolonged drainage (5%). There was a significant improvement at 3 months after surgery in the IPSS (8.6 vs. 21.6, P < 0.001), Qmax (19.5 vs. 7.7, P < 0.001), and PVR (15.8 vs. 83.9 mL, P < 0.001). Conclusion MEATP is feasible, safe and effective. Comparative studies and long-term data are required to determine its role in the surgical treatment of large-volume BPH. PMID:26019954

  14. Development of Multiobjective Optimization Techniques for Sonic Boom Minimization

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Aditi; Rajadas, John Narayan; Pagaldipti, Naryanan S.

    1996-01-01

    A discrete, semi-analytical sensitivity analysis procedure has been developed for calculating aerodynamic design sensitivities. The sensitivities of the flow variables and the grid coordinates are numerically calculated using direct differentiation of the respective discretized governing equations. The sensitivity analysis techniques are adapted within a parabolized Navier Stokes equations solver. Aerodynamic design sensitivities for high speed wing-body configurations are calculated using the semi-analytical sensitivity analysis procedures. Representative results obtained compare well with those obtained using the finite difference approach and establish the computational efficiency and accuracy of the semi-analytical procedures. Multidisciplinary design optimization procedures have been developed for aerospace applications namely, gas turbine blades and high speed wing-body configurations. In complex applications, the coupled optimization problems are decomposed into sublevels using multilevel decomposition techniques. In cases with multiple objective functions, formal multiobjective formulation such as the Kreisselmeier-Steinhauser function approach and the modified global criteria approach have been used. Nonlinear programming techniques for continuous design variables and a hybrid optimization technique, based on a simulated annealing algorithm, for discrete design variables have been used for solving the optimization problems. The optimization procedure for gas turbine blades improves the aerodynamic and heat transfer characteristics of the blades. The two-dimensional, blade-to-blade aerodynamic analysis is performed using a panel code. The blade heat transfer analysis is performed using an in-house developed finite element procedure. The optimization procedure yields blade shapes with significantly improved velocity and temperature distributions. The multidisciplinary design optimization procedures for high speed wing-body configurations simultaneously

  15. Complete mesocolic excision and central vascular ligation for colon cancer: Principle, anatomy, surgical technique, and outcomes.

    PubMed

    Kim, Nam Kyu; Kim, Young Wan; Han, Yoon Dae; Cho, Min Soo; Hur, Hyuk; Min, Byung Soh; Lee, Kang Young

    2016-09-01

    Classic colon cancer surgery refers to a wide resection of the tumor-bearing segment and the lymphatics draining along the named artery. The concept of TME has been applied to colon cancer and complete mesocolic excision (CME) in conjuction with central vascular ligation (CVL) has been introduced as the surgical treatment for colon cancer. Here, we discuss appropriate CME procedure with regard to the oncologic backgrounds, essential components, applied anatomy, laparoscopic technique, short-term, and oncologic outcomes. The introduction of CME has improved oncologic outcomes greatly in patients with colon cancer. The improved outcomes with CME can be attributed to underlying sound oncologic principles such as dissection through the proper plane of mesocolic excision, central vascular ligation, and sufficient length of proximal and distal margins. Thereby, CME technique can achieve en bloc removal of the diseased lesion with the increased amount of the colonic mesentery even though the length of for both bowel and mesentery resection remains a matter of debate. CME is a technically demanding operation thus, comprehensive understanding of the applied vascular anatomy is essential for successful CME. Favorable outcomes of open CME have been replicated with a laparoscopic approach. In future perspective, incorporating a structured education program on minimally invasive (laparoscopy or robot) CME would be beneficial. PMID:27566031

  16. Techniques for trajectory optimization using a hybrid computer

    NASA Technical Reports Server (NTRS)

    Neely, P. L.

    1975-01-01

    The use of a hybrid computer in the solution of trajectory optimization problems is described. The solution technique utilizes the indirect method and requires iterative computation of the initial condition vector of the co-state variables. Convergence of the iteration is assisted by feedback switching and contour modification. A simulation of the method in an on-line updating scheme is presented.

  17. Optimal Pid Tuning for Power System Stabilizers Using Adaptive Particle Swarm Optimization Technique

    NASA Astrophysics Data System (ADS)

    Oonsivilai, Anant; Marungsri, Boonruang

    2008-10-01

    An application of the intelligent search technique to find optimal parameters of power system stabilizer (PSS) considering proportional-integral-derivative controller (PID) for a single-machine infinite-bus system is presented. Also, an efficient intelligent search technique, adaptive particle swarm optimization (APSO), is engaged to express usefulness of the intelligent search techniques in tuning of the PID—PSS parameters. Improve damping frequency of system is optimized by minimizing an objective function with adaptive particle swarm optimization. At the same operating point, the PID—PSS parameters are also tuned by the Ziegler-Nichols method. The performance of proposed controller compared to the conventional Ziegler-Nichols PID tuning controller. The results reveal superior effectiveness of the proposed APSO based PID controller.

  18. Satellite tracking by combined optimal estimation and control techniques.

    NASA Technical Reports Server (NTRS)

    Dressler, R. M.; Tabak, D.

    1971-01-01

    Combined optimal estimation and control techniques are applied for the first time to satellite tracking systems. Both radio antenna and optical tracking systems of NASA are considered. The optimal estimation is accomplished using an extended Kalman filter resulting in an estimated state of the satellite and of the tracking system. This estimated state constitutes an input to the optimal controller. The optimal controller treats a linearized system with a quadratic performance index. The maximum principle is applied and a steady-state approximation to the resulting Riccati equation is obtained. A computer program, RATS, implementing this algorithm is described. A feasibility study of real-time implementation, tracking simulations, and parameter sensitivity studies are also reported.

  19. Supracondylar osteotomy of the paediatric femur using the locking compression plate: a refined surgical technique.

    PubMed

    Brunner, Reinald; Camathias, Carlo; Gaston, Mark; Rutz, Erich

    2013-12-01

    Locking compression plates (LCP) have been developed for paediatric patients, and these provide safe bone fixation and allow for immediate weight-bearing. These plates are becoming increasingly popular and are proving to especially useful for the treatment of proximal and distal (supracondylar) femoral osteotomies. They are thought to provide better grip in osteoporotic bone. The technique has been described in the provider's manual as well as recently by Joeris et al. (Int Orthop 2012: 36:2299-2306). The LCP system offers optimal stability after the final fixation, but temporary fixation using the originally described method is unstable, and we consider the medialisation instrument unsatisfactory as it has very small contact area with the lateral aspect of the femur and does not provide sound rotational control. For this reason we have developed a technique whereby temporary, stable fixation using fine K-wires can be attained for the proximal, diaphyseal fragment, following sound fixation with locking screws of the distal fragment. This procedure allows for full clinical (including rotation) and radiographic assessment intraoperatively, as well as fine adjustment in all three planes. This modification enables optimal correction before the final fixation and avoids unnecessary, large drill holes which may otherwise act as dangerous tress risers, endangering stability and weight-bearing. Here we describe a refined technique of the supracondylar femoral osteotomy using the paediatric LCP Condylar Plate. PMID:24432123

  20. A method to objectively optimize coral bleaching prediction techniques

    NASA Astrophysics Data System (ADS)

    van Hooidonk, R. J.; Huber, M.

    2007-12-01

    Thermally induced coral bleaching is a global threat to coral reef health. Methodologies, e.g. the Degree Heating Week technique, have been developed to predict bleaching induced by thermal stress by utilizing remotely sensed sea surface temperature (SST) observations. These techniques can be used as a management tool for Marine Protected Areas (MPA). Predictions are valuable to decision makers and stakeholders on weekly to monthly time scales and can be employed to build public awareness and support for mitigation. The bleaching problem is only expected to worsen because global warming poses a major threat to coral reef health. Indeed, predictive bleaching methods combined with climate model output have been used to forecast the global demise of coral reef ecosystems within coming decades due to climate change. Accuracy of these predictive techniques has not been quantitatively characterized despite the critical role they play. Assessments have typically been limited, qualitative or anecdotal, or more frequently they are simply unpublished. Quantitative accuracy assessment, using well established methods and skill scores often used in meteorology and medical sciences, will enable objective optimization of existing predictive techniques. To accomplish this, we will use existing remotely sensed data sets of sea surface temperature (AVHRR and TMI), and predictive values from techniques such as the Degree Heating Week method. We will compare these predictive values with observations of coral reef health and calculate applicable skill scores (Peirce Skill Score, Hit Rate and False Alarm Rate). We will (a) quantitatively evaluate the accuracy of existing coral reef bleaching predictive methods against state-of- the-art reef health databases, and (b) present a technique that will objectively optimize the predictive method for any given location. We will illustrate this optimization technique for reefs located in Puerto Rico and the US Virgin Islands.

  1. “Two-step” technique with OsiriX™ to evaluate feasibility of C2 pedicle for surgical fixation

    PubMed Central

    Marques, Luis Miguel Sousa; d’Almeida, Gonçalo Neto; Cabral, José

    2016-01-01

    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™. 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. PMID:27217652

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

    PubMed Central

    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

  3. Fitting Nonlinear Curves by use of Optimization Techniques

    NASA Technical Reports Server (NTRS)

    Hill, Scott A.

    2005-01-01

    MULTIVAR is a FORTRAN 77 computer program that fits one of the members of a set of six multivariable mathematical models (five of which are nonlinear) to a multivariable set of data. The inputs to MULTIVAR include the data for the independent and dependent variables plus the user s choice of one of the models, one of the three optimization engines, and convergence criteria. By use of the chosen optimization engine, MULTIVAR finds values for the parameters of the chosen model so as to minimize the sum of squares of the residuals. One of the optimization engines implements a routine, developed in 1982, that utilizes the Broydon-Fletcher-Goldfarb-Shanno (BFGS) variable-metric method for unconstrained minimization in conjunction with a one-dimensional search technique that finds the minimum of an unconstrained function by polynomial interpolation and extrapolation without first finding bounds on the solution. The second optimization engine is a faster and more robust commercially available code, denoted Design Optimization Tool, that also uses the BFGS method. The third optimization engine is a robust and relatively fast routine that implements the Levenberg-Marquardt algorithm.

  4. [Cervical laminoplasty--review of surgical techniques, indications, methods of efficacy evaluation, and complications].

    PubMed

    Derenda, Marek; Kowalina, Ireneusz

    2006-01-01

    Techniques of expansive cervical laminoplasty evolved in the 1970s in Japan as an alternative to laminectomy connected with many complications. They were developed and modified in the following years. Nowadays cervical laminoplasty is the standard method of posterior decompression of the cervical spine which reflects the aspiration to preserve the spine stabilising structures. Indications for laminoplasty are multilevel cervical pathological changes leading to spinal canal stenosis and myelopathy as a consequence. Historical background is discussed. Technical details of Z-type laminoplasty (Oyama), open-door laminoplasty (Hirabayashi), spinous process-splitting laminoplasty (Kurokawa), hardware-augmented laminoplasty (O'Brien with Shaffrey's modification) and dorso-lateral decompression (Ohtsuka) are described. The Japanese Orthopaedic Association scale is widely accepted for the clinical evaluation of cervical myelopathy. Effectiveness of surgical treatment is evaluated using the Hirabayashi recovery rate. Postoperative complications are: diminution of neck motion range, kyphotic deformity, axial neck pain, C5 nerve root palsy, restenosis and late deterioration of neurological postoperative outcome. Contemporary theories explaining problems connected with the complications are described. The subject is discussed based on a review of literature and own practice. PMID:17103356

  5. Peritoneal inflammatory response to surgical correction of left displaced abomasum using different techniques.

    PubMed

    Wittek, T; Fürll, M; Grosche, A

    2012-12-01

    The objective of this study was to compare the inflammatory response within the abdominal cavity between three surgical methods. The study comprised 45 cows with left displacement of the abomasum, which were allocated into three groups (n = 15). Right flank laparotomy and omentopexy (group R), left flank laparotomy and omentopexy (group L), and laparoscopic abomasopexy (group J) have been applied. Laparoscopic abomasopexy was the only technique that requires perforation of the abomasal wall. Blood and peritoneal fluid (PF) samples were obtained before, and on days 1, 2 and 3 after surgery. Macroscopic and microscopic evaluation of PF were performed. Cytological and biochemical parameters were analysed in blood and PF. No bacteria were present in PF after surgery. The number of PF leukocytes increased in all groups on day 1 after surgery with the highest value after laparoscopy (median, 1st quartile, 3rd quartile, R: 13.1, 6.4, 16.0; L: 13.6, 9.9, 17.4; J: 33.7, 21.1, 46.9 G/l). Laparotomy resulted in an increase of blood and PF CK on day 1 after surgery, whereas, laparoscopy caused an increased PF CK only. All groups had elevated PF D-dimer concentrations before surgery, with further increase in groups R and L on day 1 after surgery. PMID:23092974

  6. Should We Place Ureteral Stents in Retroperitoneal Laparoscopic Ureterolithotomy?: Consideration of Surgical Techniques and Complications

    PubMed Central

    You, Jae Hyung; Kim, Young Gon

    2014-01-01

    Purpose There is some debate over the necessity of ureteral stenting after laparoscopic ureterolithotomy. We evaluated the need for ureteral stenting after retroperitoneal laparoscopic ureterolithotomy (RLU). Materials and Methods Between January 2009 and January 2013, 41 patients underwent RLU to remove upper ureteral stones. The retroperitoneal approach was used in all patients by a single surgeon. A double J (D-J) stent was placed in the first 17 patients after the procedure but not in any of the next 24 patients. Results The mean patient age, serum creatinine levels, and stone size were not significantly different between the two groups. The stone-free rate was 100%. The mean operative time was significantly shorter in the stentless group than in the stent group (59.48 minutes vs. 77.88 minutes, p<0.001). Parenteral analgesic use and anticholinergic medication use were observed in the stent group only. The blood loss, drain removal day, and hospital stay were not significantly different between the two groups. No other significant complications occurred during or after the operation in any patients. Conclusions RLU is a safe and effective treatment modality for large impacted ureteral stones. In this study, D-J stent placement was not necessary after RLU. In the future, large-scale studies of RLU without D-J stenting, especially on the frequency of the development of complications according to the surgical technique, may be needed. PMID:25132944

  7. Systematic review of surgical treatment techniques for adult and pediatric patients with pectus excavatum

    PubMed Central

    2014-01-01

    This compares outcome measures of current pectus excavatum (PEx) treatments, namely the Nuss and Ravitch procedures, in pediatric and adult patients. Original investigations that stratified PEx patients based on current treatment and age (pediatric = 0–21; adult 17–99) were considered for inclusion. Outcome measures were: operation duration, analgesia duration, blood loss, length of stay (LOS), outcome ratings, complications, and percentage requiring reoperations. Adult implant patients (18.8%) had higher reoperation rates than adult Nuss or Ravitch patients (5.3% and 3.3% respectively). Adult Nuss patients had longer LOS (7.3 days), more strut/bar displacement (6.1%), and more epidural analgesia (3 days) than adult Ravitch patients (2.9 days, 0%, 0 days). Excluding pectus bar and strut displacements, pediatric and adult Nuss patients tended to have higher complication rates (pediatric - 38%; adult - 21%) compared to pediatric and adult Ravitch patients (12.5%; 8%). Pediatric Ravitch patients clearly had more strut displacements than adult Ravitch patients (0% and 6.4% respectively). These results suggest significantly better results in common PEx surgical repair techniques (i.e. Nuss and Ravitch) than uncommon techniques (i.e. Implants and Robicsek). The results suggest slightly better outcomes in pediatric Nuss procedure patients as compared with all other groups. We recommend that symptomatic pediatric patients with uncomplicated PEx receive the Nuss procedure. We suggest that adult patients receive the Nuss or Ravitch procedure, even though the long-term complication rates of the adult Nuss procedure require more investigation. PMID:24506826

  8. Tension plate for treatment of olecranon fractures: new surgical technique and case series study

    PubMed Central

    Lukšic, Bruno; Juric, Ivo; Boschi, Vladimir; Pogorelic, Zenon; Bekavac, Josip

    2015-01-01

    Background Our aim was to determine the effectiveness of a new surgical technique for olecranon fractures using a tension plate (TP) designed by the operating surgeon. Methods We included patients with olecranon fractures treated between September 2010 and August 2013 in our study. Treatment involved a new implant and operative technique, which combined the most favourable characteristics of 2 frequently used methods, tension band wiring and plate osteosynthesis, while eliminating their shortcomings. The new method was based on the newly constructed implant. Results Twenty patients participated in our study. We obtained the following functional results with our TP: median flexion 147.5° (interquartile range [IQR] 130°–155°), median extension 135°/deficit 10° (IQR 135°–145°), median pronation 90° (IQR 81.3°–90°), median supination 90° (IQR 80°–90°). Implant-related complications were noted in 1 patient, and implants were removed in 3 patients. The mean functional Mayo elbow performance score was 94.8 (range 65–100). The removal of the implant was considerably less frequent in patients operated using the new method and implant than in patients operated using conventional methods at our institution (p < 0.001). Mean duration of follow-up was 8 months. Conclusion Our TP for the treatment of olecranon fractures is safe and effective. Functional results are very good, with significantly decreased postoperative inconveniences and need to remove the implant. Less osteosynthetic material was used for TP construction, but stability was preserved. PMID:25427338

  9. The lateral lesser toe fillet flap for diabetic foot soft tissue closure: surgical technique and case report

    PubMed Central

    Chung, Sze-Ryn; Wong, Keng L.; Cheah, Andre E. J.

    2014-01-01

    Wound closure for the diabetic foot can be challenging and often involves amputation or reconstruction. The authors describe a surgical technique and a case report of lateral lesser toe fillet flap in the management of a diabetic foot wound. The lateral lesser toe fillet flap reconstruction is a reproducible technique that incurs comparatively minimal technical complexity and provides a favorable option in the management of diabetic foot wounds where soft tissue coverage is required. PMID:25527137

  10. Enhanced regeneration of corneal tissue via a bioengineered collagen construct implanted by a nondisruptive surgical technique.

    PubMed

    Koulikovska, Marina; Rafat, Mehrdad; Petrovski, Goran; Veréb, Zoltán; Akhtar, Saeed; Fagerholm, Per; Lagali, Neil

    2015-03-01

    Severe shortage of donor corneas for transplantation, particularly in developing countries, has prompted the advancement of bioengineered tissue alternatives. Bioengineered corneas that can withstand transplantation while maintaining transparency and compatibility with host cells, and that are additionally amenable to standardized low-cost mass production are sought. In this study, a bioengineered porcine construct (BPC) was developed to function as a biodegradable scaffold to promote corneal stromal regeneration by host cells. Using high-purity medical-grade type I collagen, high 18% collagen content and optimized EDC-NHS cross-linker ratio, BPCs were fabricated into hydrogel corneal implants with over 90% transparency and four-fold increase in strength and stiffness compared with previous versions. Remarkably, optical transparency was achieved despite the absence of collagen fibril organization at the nanoscale. In vitro testing indicated that BPC supported confluent human epithelial and stromal-derived mesenchymal stem cell populations. With a novel femtosecond laser-assisted corneal surgical model in rabbits, cell-free BPCs were implanted in vivo in the corneal stroma of 10 rabbits over an 8-week period. In vivo, transparency of implanted corneas was maintained throughout the postoperative period, while healing occurred rapidly without inflammation and without the use of postoperative steroids. BPC implants had a 100% retention rate at 8 weeks, when host stromal cells began to migrate into implants. Direct histochemical evidence of stromal tissue regeneration was observed by means of migrated host cells producing new collagen from within the implants. This study indicates that a cost-effective BPC extracellular matrix equivalent can incorporate cells passively to initiate regenerative healing of the corneal stroma, and is compatible with human stem or organ-specific cells for future therapeutic applications as a stromal replacement for treating blinding

  11. Model reduction using new optimal Routh approximant technique

    NASA Technical Reports Server (NTRS)

    Hwang, Chyi; Guo, Tong-Yi; Sheih, Leang-San

    1992-01-01

    An optimal Routh approximant of a single-input single-output dynamic system is a reduced-order transfer function of which the denominator is obtained by the Routh approximation method while the numerator is determined by minimizing a time-response integral-squared-error (ISE) criterion. In this paper, a new elegant approach is presented for obtaining the optimal Routh approximants for linear time-invariant continuous-time systems. The approach is based on the Routh canonical expansion, which is a finite-term orthogonal series of rational basis functions, and minimization of the ISE criterion. A procedure for combining the above approach with the bilinear transformation is also presented in order to obtain the optimal bilinear Routh approximants of linear time-invariant discrete-time systems. The proposed technique is simple in formulation and is amenable to practical implementation.

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

    PubMed Central

    2013-01-01

    Background 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. Methods 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. Results Fifteen important issues were extracted from the convergent interviews. Conclusion 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. PMID:23782771

  13. A technique for noise measurement optimization with spectrum analyzers

    NASA Astrophysics Data System (ADS)

    Carniti, P.; Cassina, L.; Gotti, C.; Maino, M.; Pessina, G.

    2015-08-01

    Measuring low noise of electronic devices with a spectrum analyzer requires particular care as the instrument could add significant contributions. A Low Noise Amplifier, LNA, is therefore necessary to be connected between the source to be measured and the instrument, to mitigate its effect at the LNA input. In the present work we suggest a technique for the implementation of the LNA that allows to optimize both low frequency noise and white noise, obtaining outstanding performance in a very broad frequency range.

  14. Laser treatment of 13 benign oral vascular lesions by three different surgical techniques

    PubMed Central

    Romeo, Umberto; Del Vecchio, Alessandro; Russo, Claudia; Gaimari, Gianfranco; Arnabat-Dominguez, Josep; España, Antoni J.

    2013-01-01

    Objectives: Benign Oral Vascular Lesions (BOVLs) are a group of vascular diseases characterized by congenital, inflammatory or neoplastic vascular dilations clinically evidenced as more or less wide masses of commonly dark bluish color. If traumatized BOVLs are characterized by a great risk of hemorrhage and their treatment usually requires great caution to prevent massive bleeding. In the last decades lasers have dramatically changed the way of treatment of BOVLs permitting the application of even peculiar techniques that gave interesting advantages in their management reducing hemorrhage risks. The aim of this study was to evaluate the capabilities and disadvantages of three laser assisted techniques in the management of BOVLs. Study design: In this study 13 BOVLs were treated by three different laser techniques: the traditional excisional biopsy (EB), and two less invasive techniques, the transmucosal thermocoagulation (TMT) and the intralesional photocoagulation (ILP). Two different laser devices were adopted in the study: a KTP laser (DEKA, Florence, Italy, 532nm) and a GaAlAs laser (Laser Innovation, Castelgandolfo, Italy, 808nm) selected since their great effectiveness on hemoglobin. Results: In each case, lasers permitted safe treatments of BOVLs without hemorrhages, both during the intervention and in the post-operative period. The minimally invasive techniques (TMT and ILP) permitted even the safe resolution of big lesions without tissue loss. Conclusions: Laser devices confirm to be the gold standard in BOVLs treatment, permitting even the introduction of minimal invasive surgery principles and reducing the risks of hemorrhage typical of these neoplasms. As usual in laser surgery, it is necessary a clear knowledge of the devices and of the laser-tissue interaction to optimize the results reducing risks and disadvantages. Key words:Oral vascular diseases, laser, photocoagulation. PMID:23385496

  15. Optimization of backward giant circle technique on the asymmetric bars.

    PubMed

    Hiley, Michael J; Yeadon, Maurice R

    2007-11-01

    The release window for a given dismount from the asymmetric bars is the period of time within which release results in a successful dismount. Larger release windows are likely to be associated with more consistent performance because they allow a greater margin for error in timing the release. A computer simulation model was used to investigate optimum technique for maximizing release windows in asymmetric bars dismounts. The model comprised four rigid segments with the elastic properties of the gymnast and bar modeled using damped linear springs. Model parameters were optimized to obtain a close match between simulated and actual performances of three gymnasts in terms of rotation angle (1.5 degrees ), bar displacement (0.014 m), and release velocities (<1%). Three optimizations to maximize the release window were carried out for each gymnast involving no perturbations, 10-ms perturbations, and 20-ms perturbations in the timing of the shoulder and hip joint movements preceding release. It was found that the optimizations robust to 20-ms perturbations produced release windows similar to those of the actual performances whereas the windows for the unperturbed optimizations were up to twice as large. It is concluded that robustness considerations must be included in optimization studies in order to obtain realistic results and that elite performances are likely to be robust to timing perturbations of the order of 20 ms. PMID:18089928

  16. The Role of Minimally Invasive Surgical Techniques in the Management of Large-gland Benign Prostatic Hypertrophy

    PubMed Central

    Sivarajan, Ganesh; Borofsky, Michael S; Shah, Ojas; Lingeman, James E; Lepor, Herbert

    2015-01-01

    Lower urinary tract symptoms (LUTS) secondary to benign prostatic hypertrophy (BPH) are among the most common medical issues for aging men. Population-based studies suggest that 13.8% of men in their 40s and more than 40% of men over age 60 have BPH. When LUTS are refractory to medical therapy and bothersome enough to warrant surgical intervention, transurethral resection of the prostate and open simple prostatectomy have been the historical reference-standard procedures for decades. Both procedures are highly effective and offer durable improvements in urinary functional outcomes. However, they also have the potential for considerable perioperative complications and morbidity. In an effort to limit surgical morbidity, a variety of minimally invasive surgical techniques to treat BPH have been introduced. Herein we present a comprehensive, evidence-based review of the efficacy and safety profile of modern minimally invasive treatments for large-gland BPH. PMID:26543428

  17. The Role of Minimally Invasive Surgical Techniques in the Management of Large-gland Benign Prostatic Hypertrophy.

    PubMed

    Sivarajan, Ganesh; Borofsky, Michael S; Shah, Ojas; Lingeman, James E; Lepor, Herbert

    2015-01-01

    Lower urinary tract symptoms (LUTS) secondary to benign prostatic hypertrophy (BPH) are among the most common medical issues for aging men. Population-based studies suggest that 13.8% of men in their 40s and more than 40% of men over age 60 have BPH. When LUTS are refractory to medical therapy and bothersome enough to warrant surgical intervention, transurethral resection of the prostate and open simple prostatectomy have been the historical reference-standard procedures for decades. Both procedures are highly effective and offer durable improvements in urinary functional outcomes. However, they also have the potential for considerable perioperative complications and morbidity. In an effort to limit surgical morbidity, a variety of minimally invasive surgical techniques to treat BPH have been introduced. Herein we present a comprehensive, evidence-based review of the efficacy and safety profile of modern minimally invasive treatments for large-gland BPH. PMID:26543428

  18. Technique Developed for Optimizing Traveling-Wave Tubes

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.

    1999-01-01

    A traveling-wave tube (TWT) is an electron beam device that is used to amplify electromagnetic communication waves at radio and microwave frequencies. TWT s are critical components in deep-space probes, geosynchronous communication satellites, and high-power radar systems. Power efficiency is of paramount importance for TWT s employed in deep-space probes and communications satellites. Consequently, increasing the power efficiency of TWT s has been the primary goal of the TWT group at the NASA Lewis Research Center over the last 25 years. An in-house effort produced a technique (ref. 1) to design TWT's for optimized power efficiency. This technique is based on simulated annealing, which has an advantage over conventional optimization techniques in that it enables the best possible solution to be obtained (ref. 2). A simulated annealing algorithm was created and integrated into the NASA TWT computer model (ref. 3). The new technique almost doubled the computed conversion power efficiency of a TWT from 7.1 to 13.5 percent (ref. 1).

  19. Limb Angular Deformity Correction Using Dyna-ATC: Surgical Technique, Calculation Method, and Clinical Outcome

    PubMed Central

    Park, Hoon; Kim, Hyun Woo; Park, Hui-Wan

    2011-01-01

    Purpose Dyna-ATC is a unilateral external fixator with angulator, lengthener, and translator, which allows for angular correction and compensation of the secondary displacement during angular correction. The purpose of this study is to introduce surgical technique and calculation methods and to evaluate the clinical outcome of angular deformity correction using Dyna-ATC. Materials and Methods The amounts of secondary displacement were calculated with the distances between axis of correction of angulation, Center of Rotational Angulation, and osteotomy and the amount of angular deformity. The rate of angular correction was determined to distract the corticotomy at 1 mm/day. Clinical and radiographic evaluation was performed on 13 patients who underwent deformity correction using Dyna-ATC. There were 8 proximal tibia vara, 1 tibia valga, 2 varus and 4 valgus deformities on distal femur. One patient underwent pelvic support femoral reconstruction. Concomitant lengthening was combined in all femur cases. Mean age at surgery was 17.5 years (7 to 64). Results All but one achieved bony healing and normal alignment with the index procedure. Mean mechanical axis deviation improved from 31.9 mm to 3.0 mm. The average amount of angular correction was 11.0° on tibiae and 10.0° on femora. The average length gain on femora was 6.4 cm, and the healing index averaged to 1.1 mo/cm. One patient underwent quadricepsplasty and one patient had three augmentation surgeries due to poor new bone formation. Conclusion We believe that Dyna-ATC is a useful alternative to bulky ring fixators for selective patients with angular deformity less than 30 degrees in the coronal plane around the knee joint. PMID:21786448

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

    PubMed

    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. PMID:21442420

  1. Comparison of early postoperative pain among surgical techniques for obstructive sleep apnea.

    PubMed

    Akcam, Timur; Arslan, Hasan Huseyin; Deniz, Suleyman; Genc, Hakan; Karakoc, Omer; Senkal, Serkan; Gerek, Mustafa

    2012-11-01

    One of the criticized aspects of surgeries for obstructive sleep apnea (OSA) is postoperative pain. We performed a study to compare the severity of pain occurring after different surgical techniques and to determine analgesic requirements in the first postoperative 24 h. Forty-eight patients with primary snoring or OSA who underwent anterior palatoplasty (AP), lateral pharyngoplasty (LP) or tongue base suspension suture (TBS) were included in this study. A visual analog scale (VAS) was used for measuring pain intensity. Tramadol with patient-controlled analgesia (PCA) device and when necessary rescue pethidine was used for pain relief. VAS pain scores, total PCA-tramadol consumptions and requirement of rescue analgesic in AP, LP and TBS groups were compared. Pain scores in TBS group were higher than AP group in all of the study time points except at 12th hour and LP group until the 10th hour. When compared with AP group, VAS was significantly higher in LP group at the 1st hour. Mean total tramadol consumptions were significantly different between the groups (AP-LP, p = 0.039; AP-TBS, p < 0.001; LP-TBS, p < 0.001). It was highest in the TBS group and lowest in the AP group. In the LP group, three patients (16.7 %) needed rescue analgesia in comparison with 11 (73.3 %) in the TBS group. None of the patients in the AP group needed rescue analgesic. AP is the least painful and TBS is the most painful procedure. PCA-bolus tramadol effectively treats pain caused by AP and LP; however, alleviation of pain caused by TBS usually needs rescue opioid analgesic. PMID:22699627

  2. Old technique revisited with surgical innovation: complicated Mallory–Weiss tear with bleeding gastric ulcer exclusion

    PubMed Central

    Yoshino, Osamu; Prichard, Peter J.; Choi, Julian

    2016-01-01

    Mallory–Weiss tears (MWTs) rarely require surgical intervention. A 60-year-old female presented with massive hematemesis secondary to MWT and gastric ulceration. After failure of endoscopic management, an operative approach was embarked on, with a direct surgical hemostasis of the Mallory–Weiss tear and exclusion of the gastric ulcer. This exclusion strategy may be applicable for other patients with uncontrolled upper gastrointestinal bleeding in whom a simple repair would be difficult. PMID:26757734

  3. Surgical Technique of Corrective Osteotomy for Malunited Distal Radius Fracture Using the Computer-Simulated Patient Matched Instrument.

    PubMed

    Murase, Tsuyoshi

    2016-06-01

    The conventional corrective osteotomy for malunited distal radius fracture that employs dorsal approach and insertion of a trapezoidal bone graft does not always lead to precise correction or result in a satisfactory surgical outcome. Corrective osteotomy using a volar locking plate has recently become an alternative technique. In addition, the use of patient-matched instrument (PMI) via computed tomography simulation has been developed and is expected to simplify surgical procedures and improve surgical precision. The use of PMI makes it possible to accurately position screw holes prior to the osteotomy and simultaneously perform the correction and place the volar locking plate once the osteotomy is completed. The bone graft does not necessarily require a precise block form, and the problem of the extensor tendon contacting the dorsal plate is avoided. Although PMI placement and soft tissue release technique require some degree of specialized skill, they comprise a very useful surgical procedure. On the other hand, because patients with osteoporosis are at risk of peri-implant fracture, tandem ulnar shortening surgery should be considered to avoid excessive lengthening of the radius. PMID:27454626

  4. Is the surgical knot tying technique associated with a risk for unnoticed glove perforation? An experimental study

    PubMed Central

    2014-01-01

    Background The issue of safety in the surgical procedure has recently been widely and openly discussed at the World Health Organization. The use of latex gloves is the current standard of protection during surgery, as they remain intact throughout the procedure. The present study was designed to evaluate the rate of glove perforation during a two-hand technique using polyester sutures in a controlled experimental study. Methods Hypothesis was that the gloves used during a two-hand technique using polyester suture suffer punctures. We used 150 pairs of gloves during the experiment. Each investigator performed 30 tests always using double gloving. They made five surgical knots on each test over a custom-made table specifically developed for the experiment. Ten tests were done at a time with a week- interval. The Control Group (CG) has 30 pairs of intact surgical gloves. The gloves were tested to impermeability by water filling and leaking was observed at three different times. Statistics relating to the perforation rate were analyzed using the chi-square test. A P value less than 0.05 was considered statistically significant. Results During the experiment there was no loss of gloves by drilling or inadvertent error in performing the impermeability test. No perforations were detected at any time during the impermeability test with the gloves used for sutures. Also, the CG presented no leakage of the liquid used for the test. There was no statistical difference between the groups underwent suture nor between them and the GC. Conclusion Under the studied conditions, the authors’ hypotheses could not be proved. There was no damage to the surgical gloves during the entire experiment. The authors believe that the skin abrasions observed in the ulnar side of the little finger, constant throughout the experiment, must be caused by friction. We feel there is no risk of perforation of surgical gloves during a two-hand technique using polyester suture. PMID:24991234

  5. Automated parameterization of intermolecular pair potentials using global optimization techniques

    NASA Astrophysics Data System (ADS)

    Krämer, Andreas; Hülsmann, Marco; Köddermann, Thorsten; Reith, Dirk

    2014-12-01

    In this work, different global optimization techniques are assessed for the automated development of molecular force fields, as used in molecular dynamics and Monte Carlo simulations. The quest of finding suitable force field parameters is treated as a mathematical minimization problem. Intricate problem characteristics such as extremely costly and even abortive simulations, noisy simulation results, and especially multiple local minima naturally lead to the use of sophisticated global optimization algorithms. Five diverse algorithms (pure random search, recursive random search, CMA-ES, differential evolution, and taboo search) are compared to our own tailor-made solution named CoSMoS. CoSMoS is an automated workflow. It models the parameters' influence on the simulation observables to detect a globally optimal set of parameters. It is shown how and why this approach is superior to other algorithms. Applied to suitable test functions and simulations for phosgene, CoSMoS effectively reduces the number of required simulations and real time for the optimization task.

  6. Techniques for developing reliability-oriented optimal microgrid architectures

    NASA Astrophysics Data System (ADS)

    Patra, Shashi B.

    2007-12-01

    Alternative generation technologies such as fuel cells, micro-turbines, solar etc. have been the focus of active research in the past decade. These energy sources are small and modular. Because of these advantages, these sources can be deployed effectively at or near locations where they are actually needed, i.e. in the distribution network. This is in contrast to the traditional electricity generation which has been "centralized" in nature. The new technologies can be deployed in a "distributed" manner. Therefore, they are also known as Distributed Energy Resources (DER). It is expected that the use of DER, will grow significantly in the future. Hence, it is prudent to interconnect the energy resources in a meshed or grid-like structure, so as to exploit the reliability and economic benefits of distributed deployment. These grids, which are smaller in scale but similar to the electric transmission grid, are known as "microgrids". This dissertation presents rational methods of building microgrids optimized for cost and subject to system-wide and locational reliability guarantees. The first method is based on dynamic programming and consists of determining the optimal interconnection between microsources and load points, given their locations and the rights of way for possible interconnections. The second method is based on particle swarm optimization. This dissertation describes the formulation of the optimization problem and the solution methods. The applicability of the techniques is demonstrated in two possible situations---design of a microgrid from scratch and expansion of an existing distribution system.

  7. Growth and physiological responses to surgical and gastric radio transmitter implantation techniques in subyearling chinook salmon (Oncorhynchus tshawytscha)

    USGS Publications Warehouse

    Martinelli, T.L.; Hansel, H.C.; Shively, R.S.

    1998-01-01

    We examined the effects of surgical and gastric transmitter implantation techniques on the growth, general physiology and behavior of 230 subyearling chinook salmon (Oncorhynchus tshawytscha, Walbaum) (100 mm-154 mm fork length). The transmitter weighed 1.3 g in air (0.9 g in water) and comprised, on average, 6% of the body weight of the fish (in air). Individuals were randomly assigned to an experimental group (control, surgical or gastric) and a sampling period (day 5 or day 21). Relative growth rate was expressed as% body weight gained/day. General condition was assessed by necropsy. Physiological response variables included hematocrit, leucocrit and plasma protein concentration. The mean relative growth rates of control, surgical and gastric fish were not significantly different at day 5. By day 21, the gastric group had a significantly lower relative growth rate (1.3%) as compared to the surgical group (1.8%) and the control group (1.9%) (P = 0.0001). Mean hematocrit values were significantly lower in the surgical (41.8%) and gastric (42.2%) groups as compared to controls (47.3%) at day 5 (P = 0.01), but all were within normal range for salmonids. No significant differences in hematocrit values were detected at day 21. Leucocrit values for all groups were ??? 1% in 99% of the fish. Both tagged groups had significantly lower mean plasma protein levels as compared to controls at day 5 (P = 0.001) and day 21 (P = 0.0001). At day 21 the gastric group (64.4 g 100 m1-1) had significantly lower mean plasma protein levels than the surgical group (68.8 g 100 ml-1) (P = 0.0001). Necropsies showed decreasing condition of gastrically tagged fish over time, and increasing condition of surgical fish. Paired releases of surgically and gastrically implanted yearling chinook salmon in the lower Columbia River in spring, 1996 revealed few significant differences in migration behavior through two reservoirs. We conclude that gastrically implanted fish show decreased growth and

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

    NASA Astrophysics Data System (ADS)

    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.

  9. On combining Laplacian and optimization-based mesh smoothing techniques

    SciTech Connect

    Freitag, L.A.

    1997-07-01

    Local mesh smoothing algorithms have been shown to be effective in repairing distorted elements in automatically generated meshes. The simplest such algorithm is Laplacian smoothing, which moves grid points to the geometric center of incident vertices. Unfortunately, this method operates heuristically and can create invalid meshes or elements of worse quality than those contained in the original mesh. In contrast, optimization-based methods are designed to maximize some measure of mesh quality and are very effective at eliminating extremal angles in the mesh. These improvements come at a higher computational cost, however. In this article the author proposes three smoothing techniques that combine a smart variant of Laplacian smoothing with an optimization-based approach. Several numerical experiments are performed that compare the mesh quality and computational cost for each of the methods in two and three dimensions. The author finds that the combined approaches are very cost effective and yield high-quality meshes.

  10. Machine learning techniques for energy optimization in mobile embedded systems

    NASA Astrophysics Data System (ADS)

    Donohoo, Brad Kyoshi

    Mobile smartphones and other portable battery operated embedded systems (PDAs, tablets) are pervasive computing devices that have emerged in recent years as essential instruments for communication, business, and social interactions. While performance, capabilities, and design are all important considerations when purchasing a mobile device, a long battery lifetime is one of the most desirable attributes. Battery technology and capacity has improved over the years, but it still cannot keep pace with the power consumption demands of today's mobile devices. This key limiter has led to a strong research emphasis on extending battery lifetime by minimizing energy consumption, primarily using software optimizations. This thesis presents two strategies that attempt to optimize mobile device energy consumption with negligible impact on user perception and quality of service (QoS). The first strategy proposes an application and user interaction aware middleware framework that takes advantage of user idle time between interaction events of the foreground application to optimize CPU and screen backlight energy consumption. The framework dynamically classifies mobile device applications based on their received interaction patterns, then invokes a number of different power management algorithms to adjust processor frequency and screen backlight levels accordingly. The second strategy proposes the usage of machine learning techniques to learn a user's mobile device usage pattern pertaining to spatiotemporal and device contexts, and then predict energy-optimal data and location interface configurations. By learning where and when a mobile device user uses certain power-hungry interfaces (3G, WiFi, and GPS), the techniques, which include variants of linear discriminant analysis, linear logistic regression, non-linear logistic regression, and k-nearest neighbor, are able to dynamically turn off unnecessary interfaces at runtime in order to save energy.

  11. Emerging Techniques for Dose Optimization in Abdominal CT

    PubMed Central

    Platt, Joel F.; Goodsitt, Mitchell M.; Al-Hawary, Mahmoud M.; Maturen, Katherine E.; Wasnik, Ashish P.; Pandya, Amit

    2014-01-01

    Recent advances in computed tomographic (CT) scanning technique such as automated tube current modulation (ATCM), optimized x-ray tube voltage, and better use of iterative image reconstruction have allowed maintenance of good CT image quality with reduced radiation dose. ATCM varies the tube current during scanning to account for differences in patient attenuation, ensuring a more homogeneous image quality, although selection of the appropriate image quality parameter is essential for achieving optimal dose reduction. Reducing the x-ray tube voltage is best suited for evaluating iodinated structures, since the effective energy of the x-ray beam will be closer to the k-edge of iodine, resulting in a higher attenuation for the iodine. The optimal kilovoltage for a CT study should be chosen on the basis of imaging task and patient habitus. The aim of iterative image reconstruction is to identify factors that contribute to noise on CT images with use of statistical models of noise (statistical iterative reconstruction) and selective removal of noise to improve image quality. The degree of noise suppression achieved with statistical iterative reconstruction can be customized to minimize the effect of altered image quality on CT images. Unlike with statistical iterative reconstruction, model-based iterative reconstruction algorithms model both the statistical noise and the physical acquisition process, allowing CT to be performed with further reduction in radiation dose without an increase in image noise or loss of spatial resolution. Understanding these recently developed scanning techniques is essential for optimization of imaging protocols designed to achieve the desired image quality with a reduced dose. © RSNA, 2014 PMID:24428277

  12. Arthroscopic-Assisted Acromioclavicular Joint Reconstruction Using the TightRope Device With Allograft Augmentation: Surgical Technique

    PubMed Central

    Frank, Rachel M.; Trenhaile, Scott W.

    2015-01-01

    Surgical management of acromioclavicular (AC) joint separations remains challenging, especially in the revision setting. Most commonly, Rockwood type I and II injuries are managed nonoperatively whereas type IV, V, and VI injuries are managed with surgery. Type III separations are more controversial, with evidence supporting both nonoperative and operative treatment options. Multiple different arthroscopic techniques have been described; however, there is no current gold standard. AC joint reconstruction with the TightRope device (Arthrex, Naples, FL) with the patient in the lateral decubitus position is a method of restoring joint stability that allows for a minimally invasive, low-profile fixation construct using a single drill hole through the clavicle. Allograft augmentation of this fixation construct helps to eliminate the stress risers potentially created by this device while increasing overall repair construct stability. The purpose of this article is to describe the surgical technique for arthroscopic AC joint reconstruction using a TightRope device with allograft augmentation. PMID:26759765

  13. A fuzzy optimal threshold technique for medical images

    NASA Astrophysics Data System (ADS)

    Thirupathi Kannan, Balaji; Krishnasamy, Krishnaveni; Pradeep Kumar Kenny, S.

    2012-01-01

    A new fuzzy based thresholding method for medical images especially cervical cytology images having blob and mosaic structures is proposed in this paper. Many existing thresholding algorithms may segment either blob or mosaic images but there aren't any single algorithm that can do both. In this paper, an input cervical cytology image is binarized, preprocessed and the pixel value with minimum Fuzzy Gaussian Index is identified as an optimal threshold value and used for segmentation. The proposed technique is tested on various cervical cytology images having blob or mosaic structures, compared with various existing algorithms and proved better than the existing algorithms.

  14. A fuzzy optimal threshold technique for medical images

    NASA Astrophysics Data System (ADS)

    Thirupathi Kannan, Balaji; Krishnasamy, Krishnaveni; Pradeep Kumar Kenny, S.

    2011-12-01

    A new fuzzy based thresholding method for medical images especially cervical cytology images having blob and mosaic structures is proposed in this paper. Many existing thresholding algorithms may segment either blob or mosaic images but there aren't any single algorithm that can do both. In this paper, an input cervical cytology image is binarized, preprocessed and the pixel value with minimum Fuzzy Gaussian Index is identified as an optimal threshold value and used for segmentation. The proposed technique is tested on various cervical cytology images having blob or mosaic structures, compared with various existing algorithms and proved better than the existing algorithms.

  15. Range of Hip Joint Motion in Developmental Dysplasia of the Hip Patients Following Total Hip Arthroplasty With the Surgical Technique Using the Concept of Combined Anteversion: A Study of Crowe I and II Patients.

    PubMed

    Zhang, Jingwei; Wei, Jianhe; Mao, Yuanqing; Li, Huiwu; Xie, Youzhuan; Zhu, Zhenan

    2015-12-01

    The combined anteversion surgical technique has been proposed and used in clinical practice. To more objectively evaluate the feasibility of this surgical technique using combined anteversion concept for DDH patients, we studied 34 DDH patients (40 hips) in this research. Every patient underwent pelvic CT scans before and after surgery and the HHSs were recorded. Optimal range of joint motion was measured using a three-dimensional reconstruction technique and a dynamic measurement technique. The results revealed that joint function met the requirements of daily life and the range of motion was not over-limited by impingement between the prosthesis and the skeleton. Moreover, the combined anteversion was found to be the most critical parameter in this study. PMID:26228491

  16. Surgical approach in primary total hip arthroplasty: anatomy, technique and clinical outcomes

    PubMed Central

    Petis, Stephen; Howard, James L.; Lanting, Brent L.; Vasarhelyi, Edward M.

    2015-01-01

    Total hip arthroplasty (THA) has revolutionized the treatment of hip arthritis. A number of surgical approaches to the hip joint exist, each with unique advantages and disadvantages. The most commonly used approaches include the direct anterior, direct lateral and posterior approaches. A number of technical intricacies allow safe and efficient femoral and acetabular reconstruction when using each approach. Hip dislocation, abductor insufficiency, fracture and nerve injury are complications of THA, although their relative risk varies by approach. Numerous clinical trials have sought to elicit differences in patient-reported outcomes, complication rates and return to function among the surgical approaches. This review outlines some of the technical pearls of performing a THA through either a direct anterior, direct lateral or posterior approach. A literature review outlines the impact of surgical approach on clinical outcomes and clinically relevant complication rates. PMID:25799249

  17. Optimizing third molar autotransplantation: applications of reverse-engineered surgical templates and rapid prototyping of three-dimensional teeth.

    PubMed

    Park, Ji-Man; Tatad, Jacquiline Czar I; Landayan, Maria Erika A; Heo, Seong-Joo; Kim, Sun-Jong

    2014-09-01

    The success of autogenous tooth transplantation depends on the vitality of the periodontal ligament attached to the donor tooth, and its viability decreases when it is exposed extraorally. This report describes the case of a 16-year-old patient in whom a rapid prototyped tooth model was performed using cone-beam technology and a surgical template guide for autotransplantation as an effective technique for a critical time-based procedure. PMID:25043146

  18. Techniques to reduce pain associated with hair transplantation: optimizing anesthesia and analgesia.

    PubMed

    Nusbaum, Bernard P

    2004-01-01

    The importance of pain control in hair transplantation cannot be overemphasized. Adequate preoperative sedation to reduce anxiety, raise pain threshold, and induce amnesia is fundamental to minimizing operative pain. Most of the pain associated with the procedure results from injection of the local anesthetic. Once initial anesthesia is achieved, proper maintenance of anesthesia is of paramount importance especially with the trend toward larger numbers of grafts being performed in one session with prolonged operative times. The choice of local anesthetic agents, infiltration technique, optimal field blocks and nerve blocks, proper hemostasis, timely repetition of anesthesia, and use of analgesics intraoperatively, with the goal of maintaining the patient pain-free during the procedure, are fundamental. In addition, reduced pain on infiltration can be achieved with buffering and warming of the local anesthetic solution as well as techniques to decrease sensation or partially anesthetize the skin prior to injection. Techniques such as bupivacaine donor area field block in the immediate postoperative period and early administration of analgesics can greatly influence postoperative pain. Along with excellent cosmetic results attainable with modern techniques, improving patients' experiences during the surgical process will enhance the public perception of hair transplantation and will encourage prospective patients to seek this treatment modality. PMID:14979739

  19. A Novel Surgical Technique for Removing Buried Cannulated Screws Using a Guidewire and Countersink: A Report of Two Cases

    PubMed Central

    Chen, Yongsheng; Giri, Krishna Prasad; Pearce, Christopher Jon

    2015-01-01

    Removal of metal implants is a common procedure that is performed for a variety of indications. However, problems such as a buried screw head may occasionally arise and render hardware removal difficult or even impossible. The problem is further compounded when the initial screw was inserted percutaneously or via a minimally-invasive (MIS) technique. In the present paper, we introduce a novel, minimally invasive technique to remove buried cannulated screws which obviates the need for excessive extension of the skin incision, surgical exploration, soft tissue dissection or excess bone removal, which surgeons may otherwise have to undertake to uncover the buried screw head. This technique is especially useful in removing cannulated screws which have been inserted using small stab incisions and MIS techniques initially. This technique can be applied to the removal of buried cannulated screws which are placed into any bone in the body. PMID:26161159

  20. High-level power analysis and optimization techniques

    NASA Astrophysics Data System (ADS)

    Raghunathan, Anand

    1997-12-01

    This thesis combines two ubiquitous trends in the VLSI design world--the move towards designing at higher levels of design abstraction, and the increasing importance of power consumption as a design metric. Power estimation and optimization tools are becoming an increasingly important part of design flows, driven by a variety of requirements such as prolonging battery life in portable computing and communication devices, thermal considerations and system cooling and packaging costs, reliability issues (e.g. electromigration, ground bounce, and I-R drops in the power network), and environmental concerns. This thesis presents a suite of techniques to automatically perform power analysis and optimization for designs at the architecture or register-transfer, and behavior or algorithm levels of the design hierarchy. High-level synthesis refers to the process of synthesizing, from an abstract behavioral description, a register-transfer implementation that satisfies the desired constraints. High-level synthesis tools typically perform one or more of the following tasks: transformations, module selection, clock selection, scheduling, and resource allocation and assignment (also called resource sharing or hardware sharing). High-level synthesis techniques for minimizing the area, maximizing the performance, and enhancing the testability of the synthesized designs have been investigated. This thesis presents high-level synthesis techniques that minimize power consumption in the synthesized data paths. This thesis investigates the effects of resource sharing on the power consumption in the data path, provides techniques to efficiently estimate power consumption during resource sharing, and resource sharing algorithms to minimize power consumption. The RTL circuit that is obtained from the high-level synthesis process can be further optimized for power by applying power-reducing RTL transformations. This thesis presents macro-modeling and estimation techniques for switching

  1. A Deep-Cutting-Plane Technique for Reverse Convex Optimization.

    PubMed

    Moshirvaziri, K; Amouzegar, M A

    2011-08-01

    A large number of problems in engineering design and in many areas of social and physical sciences and technology lend themselves to particular instances of problems studied in this paper. Cutting-plane methods have traditionally been used as an effective tool in devising exact algorithms for solving convex and large-scale combinatorial optimization problems. Its utilization in nonconvex optimization has been also promising. A cutting plane, essentially a hyperplane defined by a linear inequality, can be used to effectively reduce the computational efforts in search of a global solution. Each cut is generated in order to eliminate a large portion of the search domain. Thus, a deep cut is intuitively superior in which it will exclude a larger set of extraneous points from consideration. This paper is concerned with the development of deep-cutting-plane techniques applied to reverse-convex programs. An upper bound and a lower bound for the optimal value are found, updated, and improved at each iteration. The algorithm terminates when the two bounds collapse or all the generated subdivisions have been fathomed. Finally, computational considerations and numerical results on a set of test problems are discussed. An illustrative example, walking through the steps of the algorithm and explaining the computational process, is presented. PMID:21296710

  2. An optimal merging technique for high-resolution precipitation products

    SciTech Connect

    Houser, Paul

    2011-01-01

    Precipitation products are currently available from various sources at higher spatial and temporal resolution than any time in the past. Each of the precipitation products has its strengths and weaknesses in availability, accuracy, resolution, retrieval techniques and quality control. By merging the precipitation data obtained from multiple sources, one can improve its information content by minimizing these issues. However, precipitation data merging poses challenges of scale-mismatch, and accurate error and bias assessment. In this paper we present Optimal Merging of Precipitation (OMP), a new method to merge precipitation data from multiple sources that are of different spatial and temporal resolutions and accuracies. This method is a combination of scale conversion and merging weight optimization, involving performance-tracing based on Bayesian statistics and trend-analysis, which yields merging weights for each precipitation data source. The weights are optimized at multiple scales to facilitate multiscale merging and better precipitation downscaling. Precipitation data used in the experiment include products from the 12-km resolution North American Land Data Assimilation (NLDAS) system, the 8-km resolution CMORPH and the 4-km resolution National Stage-IV QPE. The test cases demonstrate that the OMP method is capable of identifying a better data source and allocating a higher priority for them in the merging procedure, dynamically over the region and time period. This method is also effective in filtering out poor quality data introduced into the merging process.

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

    PubMed

    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. PMID:26826455

  4. Surgical Airway

    PubMed Central

    Patel, Sapna A; Meyer, Tanya K

    2014-01-01

    Close to 3% of all intubation attempts are considered difficult airways, for which a plan for a surgical airway should be considered. Our article provides an overview of the different types of surgical airways. This article provides a comprehensive review of the main types of surgical airways, relevant anatomy, necessary equipment, indications and contraindications, preparation and positioning, technique, complications, and tips for management. It is important to remember that the placement of a surgical airway is a lifesaving procedure and should be considered in any setting when one “cannot intubate, cannot ventilate”. PMID:24741501

  5. [Surgical treatment of genital prolapse with a new lateral prosthetic hysteropexia technique combining vaginal and laparoscopic methods].

    PubMed

    Husaunndee, M; Rousseau, E; Deleflie, M; Geoffrion, H; Dallay, D; Descamps, P

    2003-06-01

    We describe a new surgical treatment of pelvic organ prolapse. The anterior and medium compartments are treated by a transversal hysteropexy by means of an anterior prosthesis fixed by vaginal route and by laparoscopy. The principle is based on the operative technique described by Kapandji but the prosthesis is fixed to the fascia of the external oblique muscle in a subperitoneal path. The posterior compartment is treated by a vaginal route exclusively. A posterior prosthesis is placed in the rectovaginal space and fixed to the elevator muscles. Further studies are necessary to evaluate this new operative technique. PMID:12843879

  6. Current surgical instrument labeling techniques may increase the risk of unintentionally retained foreign objects: a hypothesis

    PubMed Central

    2013-01-01

    Background Marking of surgical instruments is essential to ensure their proper identification after sterile processing. The National Quality Forum defines unintentionally retained foreign objects in a surgical patient as a serious reportable event also called "never event." Presentation of the hypothesis We hypothesize that established practices of surgical instrument identification using unkempt tape labels and plastic tags may expose patients to "never events" from retained disintegrating labels. Testing of the hypothesis We demonstrate the near miss of a "never event" during a surgical case in which the breakage of an instrument label remained initially unwitnessed. A fragment of the plastic label was accidentally found in the wound upon closing. Further clinical testing of the occurrence of this "never event" appears not feasible. As the name implies a patient should never be exposed to the risk of fragmenting labels. Implication of the hypothesis Current practice does not mandate verifying intact instrument markers as part of the instrument count. The clinical confirmation of our hypothesis mandates a change in perioperative practice: Mechanical labels need to undergo routine inspection and maintenance. The perioperative count must not only verify the quantity of surgical instruments but also the intactness of labels to ensure that no part of an instrument is left behind. Proactive maintenance of taped and dipped labels should be performed routinely. The implementation of newer labeling technologies - such as laser engraved codes - appears to eliminate risks seen in traditional mechanical labels. This article reviews current instrument marking technologies, highlights shortcomings and recommends safe instrument handling and marking practices implementing newer available technologies. PMID:24079615

  7. Surgical Technologists

    MedlinePlus

    ... in place during the procedure, or set up robotic surgical equipment. Technologists also may handle specimens taken ... sterilization techniques, how to set up technical or robotic equipment, and preventing and controlling infections. In addition ...

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

    PubMed Central

    Juodzbalys, Gintaras

    2015-01-01

    ABSTRACT 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. PMID:25937873

  9. Application of multivariable search techniques to structural design optimization

    NASA Technical Reports Server (NTRS)

    Jones, R. T.; Hague, D. S.

    1972-01-01

    Multivariable optimization techniques are applied to a particular class of minimum weight structural design problems: the design of an axially loaded, pressurized, stiffened cylinder. Minimum weight designs are obtained by a variety of search algorithms: first- and second-order, elemental perturbation, and randomized techniques. An exterior penalty function approach to constrained minimization is employed. Some comparisons are made with solutions obtained by an interior penalty function procedure. In general, it would appear that an interior penalty function approach may not be as well suited to the class of design problems considered as the exterior penalty function approach. It is also shown that a combination of search algorithms will tend to arrive at an extremal design in a more reliable manner than a single algorithm. The effect of incorporating realistic geometrical constraints on stiffener cross-sections is investigated. A limited comparison is made between minimum weight cylinders designed on the basis of a linear stability analysis and cylinders designed on the basis of empirical buckling data. Finally, a technique for locating more than one extremal is demonstrated.

  10. A technique for integrating engine cycle and aircraft configuration optimization

    NASA Technical Reports Server (NTRS)

    Geiselhart, Karl A.

    1994-01-01

    A method for conceptual aircraft design that incorporates the optimization of major engine design variables for a variety of cycle types was developed. The methodology should improve the lengthy screening process currently involved in selecting an appropriate engine cycle for a given application or mission. The new capability will allow environmental concerns such as airport noise and emissions to be addressed early in the design process. The ability to rapidly perform optimization and parametric variations using both engine cycle and aircraft design variables, and to see the impact on the aircraft, should provide insight and guidance for more detailed studies. A brief description of the aircraft performance and mission analysis program and the engine cycle analysis program that were used is given. A new method of predicting propulsion system weight and dimensions using thermodynamic cycle data, preliminary design, and semi-empirical techniques is introduced. Propulsion system performance and weights data generated by the program are compared with industry data and data generated using well established codes. The ability of the optimization techniques to locate an optimum is demonstrated and some of the problems that had to be solved to accomplish this are illustrated. Results from the application of the program to the analysis of three supersonic transport concepts installed with mixed flow turbofans are presented. The results from the application to a Mach 2.4, 5000 n.mi. transport indicate that the optimum bypass ratio is near 0.45 with less than 1 percent variation in minimum gross weight for bypass ratios ranging from 0.3 to 0.6. In the final application of the program, a low sonic boom fix a takeoff gross weight concept that would fly at Mach 2.0 overwater and at Mach 1.6 overland is compared with a baseline concept of the same takeoff gross weight that would fly Mach 2.4 overwater and subsonically overland. The results indicate that for the design mission

  11. Comparison of the Outcomes and Recurrence with Three Surgical Techniques for Chronic Subdural Hematoma: Single, Double Burr Hole, and Double Burr Hole Drainage with Irrigation

    PubMed Central

    Jang, Kyoung-Min; Hwang, Sung-Nam; Park, Yong-Sook; Nam, Taek-Kyun

    2015-01-01

    Objective Chronic subdural hematoma (CSDH), a disease commonly encountered by neurosurgeons, is treated by burr hole drainage (BHD). However, the optimal surgical technique among the three types of BHD has not been determined. Methods We conducted a retrospective study on BHD performed on 93 patients who were diagnosed with CSDH. The subjects were divided into three groups based on the surgical technique performed: single BHD without irrigation (Group A, n=31), double BHD without irrigation (Group B, n=32), and double BHD with irrigation (Group C, n=30). The clinical factors, radiological factors and recurrences were compared between the three groups. Moreover, independent factors affecting the recurrence were analyzed. Results The change in hematoma thickness was 29.77±7.94%, 49.73±12.87%, and 75.29±4.32% for Group A, B, and C, respectively, while the change in midline shift was 40.81±15.47%, 51.78±10.94%, and 56.16±16.16%, respectively. Thus, Group C showed the most effective for resolution of hematoma and midline shift (p<0.05). Group A, B, and C had 12 cases (38.7%), 8 cases (25.0%), and 3 cases (10.0%) of recurrences, respectively. Group C had a statistically significantly fewer recurrence rate than Group A (p<0.05). Double burr hole, irrigation, and coagulopathy were each identified as independent factors that reduce recurrence (p<0.05). Conclusion Among the three techniques, the double BHD with saline irrigation resulted in the fewest recurrences. It is probably the most effective technique for preventing the recurrence of CSDH. PMID:27169069

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

    SciTech Connect

    Shah, Chirag; Vicini, Frank A.

    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.

  13. Surgical technique: hemi-extensor carpi radialis brevis tenodesis for stabilizing the midcarpal joint in Ehlers-Danlos syndrome.

    PubMed

    Krijgh, David D; Harley, Oliver J; Hovius, Steven E; Coert, J Henk; Walbeehm, Erik T

    2014-10-01

    Patients with the hypermobility type of Ehlers-Danlos (EDS-HT) often complain of wrist pain, usually originating from subluxations. As a result of the laxity, wrist function in these patients can be highly limited. This paper presents a surgical technique that stabilizes the lunocapitate joint with the use of an extensor carpi radialis brevis strip. Five patients with confirmed EDS-HT were treated with an extensor carpi radialis brevis tenodesis for their midcarpal instability. Two patients presented with complications following surgery, one major and one minor. This paper presents a potentially satisfactory surgical solution to recurrent midcarpal instability in EDS-HT patients and demonstrates that the use of an autologous tendon might be feasible in spite of a background of abnormal collagen metabolism. PMID:25194773

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

    PubMed

    Ahsan, Rauf M; Early, Sarah A; O'Meara, Anne; Nölke, Lars

    2009-12-01

    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. PMID:19864154

  15. Laparoscopic partial cholecystectomy: A safe and effective alternative surgical technique in “difficult cholecystectomies”

    PubMed Central

    Kulen, Fatih; Tihan, Deniz; Duman, Uğur; Bayam, Emrah; Zaim, Gökhan

    2016-01-01

    Objective Laparoscopic cholecystectomy has become the “gold standard” for benign gallbladder diseases due to its advantages. In the presence of inflammation or fibrosis, the risk of bleeding and bile duct injury is increased during dissection. Laparoscopic partial cholecystectomy (LPC) is a feasible and safe method to prevent bile duct injuries and decrease the conversion (to open cholecystectomy) rates in difficult cholecystectomies where anatomical structures could not be demonstrated clearly. Material and Methods The feasibility, efficiency, and safety of LPC were investigated. The data of 80 patients with cholelithiasis who underwent LPC (n=40) and conversion cholecystectomy (CC) (n=40) were retrospectively examined. Demographic characteristics, ASA scores, operating time, drain usage, requirement for intensive care, postoperative length of hospital stay, surgical site infection, antibiotic requirement and complication rates were compared. Results The median ASA value was 1 in the CC group and 2 in the LPC group. Mean operation time was 123 minutes in the CC group, and 87.50 minutes in the LPC group. Surgical drains were used in 16 CC patients and 4 LPC patients. There was no significant difference between groups in postoperative length of intensive care unit stay (p=0.241). When surgical site infections were compared, the difference was at the limit of statistical significance (p=0.055). Early complication rates were not different (p=0.608) but none of the patients in the LPC group suffered from late complications. Conclusion LPC is an efficient and safe way to decrease the conversion rate. LPC seems to be an alternative procedure to CC with advantages of shorter operating time, lower rates of surgical site infection, shorter postoperative hospitalization and fewer complications in high-risk patients. PMID:27528821

  16. Modern surgical techniques for management of soft tissue sarcomas involving the spine: outcomes and complications.

    PubMed

    Mattei, Tobias A; Teles, Alisson R; Mendel, Ehud

    2015-04-01

    Several types of soft tissue sarcomas may locally extend to the spine. The best therapeutic strategy for such lesions strongly depends on the histological diagnosis. In this article the authors provide an up-to-date review of current guidelines regarding the management of soft tissue sarcomas involving the spine. Special attention is given to outcomes and complications of modern surgical series in order to highlight current challenges in the management of such lesions. PMID:25413665

  17. Alveolar Antral Artery: Review of Surgical Techniques Involving this Anatomic Structure

    PubMed Central

    Rahpeyma, Amin; Khajehahmadi, Saeedeh

    2014-01-01

    Introduction: The horizontal bony canal in the lateral maxillary wall is the site of anastomosis between the arterial branches from the posterior superior alveolar artery (PSAa) and the infraorbital artery. This anatomic structure is known as the ‘alveolar antral artery’. Materials and Methods: We performed a literature review. The anatomic location of the alveolar antral artery in the lateral maxillary sinus wall was researched and its importance in surgical procedures routinely performed on this bony wall discussed. Results: This artery can be accidentally involved during surgical procedures on the lateral maxillary sinus wall, such as open sinus lift surgery, horizontal osteotomy of the maxilla, Le Fort I fracture treatment, and Caldwell-Luc surgeries. Conclusion: The alveolar antral artery is an important anatomic structure in the lateral maxillary sinus wall. A preoperative cone beam computed tomography (CBCT) scan can be used as a good diagnostic procedure to reduce surgical complications in suspected cases as well as conditions that may involve this artery. PMID:24744995

  18. Production of piglets with sexed semen employing a non-surgical insemination technique.

    PubMed

    Grossfeld, R; Klinc, P; Sieg, B; Rath, D

    2005-05-01

    The aim of the present study was to ascertain whether multiparous sows could successfully be inseminated with sexed semen non-surgically. Spermatozoa were stained with Hoechst 33342 and separated flowcytometrically in X- and Y-chromosome bearing sperm populations employing the Beltsville Sperm Sexing Technology (BSST). After weaning, estrus was induced in sows with PMSG and hCG. Animals were inseminated once per estrus non-surgically with a specially designed catheter into the tip of the uterine horn, employing 50x10(6) of either sexed or non-sexed spermatozoa diluted in 2 ml Androhep. Pregnant sows were allowed to go to term. Mean pregnancy rate from inseminations with unsexed spermatozoa was 54.5% whereas inseminations with sexed spermatozoa resulted in 33.3% pregnant sows. All but one piglet born after insemination with sexed semen were of the predicted sex. The sex of those piglets born after inseminations with non-sexed spermatozoa was 61.1% for male and 38.9% for female sex. It is concluded that non-surgically inseminations with flowcytometrically sexed spermatozoa can be conducted successfully. PMID:15826689

  19. Surgical hand antisepsis in veterinary practice: evaluation of soap scrubs and alcohol based rub techniques.

    PubMed

    Verwilghen, Denis R; Mainil, Jacques; Mastrocicco, Emilie; Hamaide, Annick; Detilleux, Johann; van Galen, Gaby; Serteyn, Didier; Grulke, Sigrid

    2011-12-01

    Recent studies have shown that hydro-alcoholic solutions are more efficient than traditional medicated soaps in the pre-surgical hand antisepsis of human surgeons but there is little veterinary literature on the subject. The aim of this study was to compare the efficiency of medicated soaps and a hydro-alcoholic solution prior to surgery using an in-use testing method in a veterinary setting. A preliminary trial was performed that compared the mean log(10) number of bacterial colony forming units (CFU) and the reduction factors (RF) between two 5-min hand-scrubbing sessions using different soaps, namely, povidone iodine (PVP) and chlorhexidine gluconate (CHX), and the 1.5-min application of a hydro-alcoholic rub. A clinical in-use trial was then used to compare the hydro-alcoholic rub and CHX in a surgical setting. Sampling was performed using finger printing on agar plates. The hydro-alcoholic rub and CHX had a similar immediate effect, although the sustained effect was significantly better for the hydro-alcoholic rub, while PVP had a significantly lower immediate and sustained effect. The hydro-alcoholic rub showed good efficiency in the clinical trial and could be considered as a useful alternative method for veterinary surgical hand antisepsis. PMID:21316990

  20. An in-use microbiological comparison of two surgical hand disinfection techniques in cardiothoracic surgery: hand rubbing versus hand scrubbing.

    PubMed

    Carro, C; Camilleri, L; Traore, O; Badrikian, L; Legault, B; Azarnoush, K; Dualé, C; De Riberolles, C

    2007-09-01

    Surgical site infection after heart surgery increases morbidity and mortality. The method of presurgical hand disinfection could influence the infection risk. From February to April 2003, we compared the microbiological efficacy of hand-rubbing (R) and hand-scrubbing (S) procedures. The surgical team alternately used hand-scrubbing or hand-rubbing techniques every two weeks. Fingertip impressions were taken before and immediately after hand disinfection, every 2h and at the end of the operation. Acceptability of hand rubbing was assessed by a questionnaire. Mean durations of surgical procedures were 259+/-68 and 244+/-69min for groups S and R respectively (P=0.43). Bacterial counts immediately after hand disinfection were comparable with the two techniques, but significantly lower in group R at the end of surgery. No differences were observed between the percentages of negative samples taken after 2h, 4h and at the end of surgery between the two groups. Bacterial skin flora reduction immediately after hand disinfection, after 2h and 4h of operating time and at the end of surgery was better in group R, but the difference was not statistically significant. Before surgery, the hand-rubbing method with alcohol solution preceded by hand washing with mild neutral soap is as effective as hand scrubbing to reduce bacterial counts on hands. It decreased the bacterial counts both immediately after hand disinfection and at the end of long cardiothoracic surgical procedures. The acceptability of hand rubbing was excellent and it can be considered to be a valid alternative to the conventional hand-scrubbing protocol. PMID:17719131

  1. Cartilage repair: A review of Stanmore experience in the treatment of osteochondral defects in the knee with various surgical techniques

    PubMed Central

    Vijayan, S; Bentley, G; Briggs, TWR; Skinner, JA; Carrington, RWJ; Pollock, R; Flanagan, AM

    2010-01-01

    Articular cartilage damage in the young adult knee, if left untreated, it may proceed to degenerative osteoarthritis and is a serious cause of disability and loss of function. Surgical cartilage repair of an osteochondral defect can give the patient significant relief from symptoms and preserve the functional life of the joint. Several techniques including bone marrow stimulation, cartilage tissue based therapy, cartilage cell seeded therapies and osteotomies have been described in the literature with varying results. Established techniques rely mainly on the formation of fibro-cartilage, which has been shown to degenerate over time due to shear forces. The implantation of autologous cultured chondrocytes into an osteochondral defect, may replace damaged cartilage with hyaline or hyaline-like cartilage. This clinical review assesses current surgical techniques and makes recommendations on the most appropriate method of cartilage repair when managing symptomatic osteochondral defects of the knee. We also discuss the experience with the technique of autologous chondrocyte implantation at our institution over the past 11 years. PMID:20697474

  2. Design of vibration isolation systems using multiobjective optimization techniques

    NASA Technical Reports Server (NTRS)

    Rao, S. S.

    1984-01-01

    The design of vibration isolation systems is considered using multicriteria optimization techniques. The integrated values of the square of the force transmitted to the main mass and the square of the relative displacement between the main mass and the base are taken as the performance indices. The design of a three degrees-of-freedom isolation system with an exponentially decaying type of base disturbance is considered for illustration. Numerical results are obtained using the global criterion, utility function, bounded objective, lexicographic, goal programming, goal attainment and game theory methods. It is found that the game theory approach is superior in finding a better optimum solution with proper balance of the various objective functions.

  3. Techniques for developing approximate optimal advanced launch system guidance

    NASA Technical Reports Server (NTRS)

    Feeley, Timothy S.; Speyer, Jason L.

    1991-01-01

    An extension to the authors' previous technique used to develop a real-time guidance scheme for the Advanced Launch System is presented. The approach is to construct an optimal guidance law based upon an asymptotic expansion associated with small physical parameters, epsilon. The trajectory of a rocket modeled as a point mass is considered with the flight restricted to an equatorial plane while reaching an orbital altitude at orbital injection speeds. The dynamics of this problem can be separated into primary effects due to thrust and gravitational forces, and perturbation effects which include the aerodynamic forces and the remaining inertial forces. An analytic solution to the reduced-order problem represented by the primary dynamics is possible. The Hamilton-Jacobi-Bellman or dynamic programming equation is expanded in an asymptotic series where the zeroth-order term (epsilon = 0) can be obtained in closed form.

  4. On improving storm surge forecasting using an adjoint optimal technique

    NASA Astrophysics Data System (ADS)

    Li, Yineng; Peng, Shiqiu; Yan, Jing; Xie, Lian

    2013-12-01

    A three-dimensional ocean model and its adjoint model are used to simultaneously optimize the initial conditions (IC) and the wind stress drag coefficient (Cd) for improving storm surge forecasting. To demonstrate the effect of this proposed method, a number of identical twin experiments (ITEs) with a prescription of different error sources and two real data assimilation experiments are performed. Results from both the idealized and real data assimilation experiments show that adjusting IC and Cd simultaneously can achieve much more improvements in storm surge forecasting than adjusting IC or Cd only. A diagnosis on the dynamical balance indicates that adjusting IC only may introduce unrealistic oscillations out of the assimilation window, which can be suppressed by the adjustment of the wind stress when simultaneously adjusting IC and Cd. Therefore, it is recommended to simultaneously adjust IC and Cd to improve storm surge forecasting using an adjoint technique.

  5. Optimal technique for maximal forward rotating vaults in men's gymnastics.

    PubMed

    Hiley, Michael J; Jackson, Monique I; Yeadon, Maurice R

    2015-08-01

    In vaulting a gymnast must generate sufficient linear and angular momentum during the approach and table contact to complete the rotational requirements in the post-flight phase. This study investigated the optimization of table touchdown conditions and table contact technique for the maximization of rotation potential for forwards rotating vaults. A planar seven-segment torque-driven computer simulation model of the contact phase in vaulting was evaluated by varying joint torque activation time histories to match three performances of a handspring double somersault vault by an elite gymnast. The closest matching simulation was used as a starting point to maximize post-flight rotation potential (the product of angular momentum and flight time) for a forwards rotating vault. It was found that the maximized rotation potential was sufficient to produce a handspring double piked somersault vault. The corresponding optimal touchdown configuration exhibited hip flexion in contrast to the hyperextended configuration required for maximal height. Increasing touchdown velocity and angular momentum lead to additional post-flight rotation potential. By increasing the horizontal velocity at table touchdown, within limits obtained from recorded performances, the handspring double somersault tucked with one and a half twists, and the handspring triple somersault tucked became theoretically possible. PMID:26026290

  6. Optimal exposure techniques for iodinated contrast enhanced breast CT

    NASA Astrophysics Data System (ADS)

    Glick, Stephen J.; Makeev, Andrey

    2016-03-01

    Screening for breast cancer using mammography has been very successful in the effort to reduce breast cancer mortality, and its use has largely resulted in the 30% reduction in breast cancer mortality observed since 1990 [1]. However, diagnostic mammography remains an area of breast imaging that is in great need for improvement. One imaging modality proposed for improving the accuracy of diagnostic workup is iodinated contrast-enhanced breast CT [2]. In this study, a mathematical framework is used to evaluate optimal exposure techniques for contrast-enhanced breast CT. The ideal observer signal-to-noise ratio (i.e., d') figure-of-merit is used to provide a task performance based assessment of optimal acquisition parameters under the assumptions of a linear, shift-invariant imaging system. A parallel-cascade model was used to estimate signal and noise propagation through the detector, and a realistic lesion model with iodine uptake was embedded into a structured breast background. Ideal observer performance was investigated across kVp settings, filter materials, and filter thickness. Results indicated many kVp spectra/filter combinations can improve performance over currently used x-ray spectra.

  7. Surgical Revascularization versus Percutaneous Coronary Intervention and Optimal Medical Therapy in Diabetic Patients with Multi-Vessel Coronary Artery Disease.

    PubMed

    Giustino, Gennaro; Dangas, George D

    2015-01-01

    Coronary artery disease (CAD) is the leading cause of death in patients with diabetes mellitus (DM). Patients with DM and CAD undergoing revascularization with either a surgical or a percutaneous approach are at higher risk of adverse outcomes and mortality compared with non-DM patients. It is within this background that the optimal choice of revascularization is of critical importance in this high-risk population. The large FREEDOM trial randomized 1900 patients with DM and multivessel CAD to either revascularization with coronary artery by-pass graft (CABG) surgery or percutaneous coronary intervention (PCI). Compared with PCI, CABG significantly reduced the rates of death and myocardial infarction but was associated with a higher risk of stroke. In a real-world setting the decision-making process for the optimal revascularization strategy in these patients is challenging as many clinical factors may influence the decision to either pursue a surgical or a percutaneous revascularization. However, the current consensus is that CABG should be the preferred revascularization strategy in diabetic patients with extensive multivessel CAD. PMID:26255239

  8. Sigmoid vaginoplasty in testicular feminising syndrome: surgical technique, outcome and review of the literature.

    PubMed

    Sinha, Rahul Janak; Bhaskar, Ved; Mehrotra, Seema; Singh, Vishwajeet

    2016-01-01

    Vaginal agenesis occurs in approximately 1:5000 live female births. It results from failure of the sinovaginal bulbs to develop and form the vaginal plate. Mayer-Rokitansky-Kuster-Hauser syndrome (MRKH) is the most common cause of vaginal absence followed by complete or partial androgen insensitivity syndrome. Treatment of these patients encompasses a spectrum from simple non-operative dilation to the more complicated surgical creation of a neovagina. We present a case of a patient with testicular feminising syndrome who was reared as a female and underwent bilateral gonadal excision and sigmoid vaginoplasty. PMID:26873917

  9. Minced articular cartilage--basic science, surgical technique, and clinical application.

    PubMed

    McCormick, Frank; Yanke, Adam; Provencher, Matthew T; Cole, Brian J

    2008-12-01

    Minced articular cartilage procedures are attractive surgical approaches for repairing articular cartilage, as they are 1-staged, autologous, and inserted on a carrier that can potentially be placed arthroscopically. The principle of mincing the autologous donor cartilage is to create a larger surface area for cartilage expansion. Placement on a scaffold carrier allows for a chondro-inductive and chondro-conductive milieu. Early animal and preclinical models have demonstrated hyaline-like tissue repair. Further work needs to be conducted in this promising approach. PMID:19011553

  10. A Comparasion in Graft Resorption between Three Techniques of Diced Cartilage Using Surgical Blade, Electrical Grinder and Grater in Rabbit

    PubMed Central

    Manafi, Ali; Sabet, Mohammad; Emami, Abolhasan; Vasei, Mohammad; Mosavi, Jaber; Manafi, Amir; Hamedi, Zahra Sadat; Manafi, Farzad; Mehrabani, Golnoush; Manafi, Navid

    2014-01-01

    BACKGROUND In recent years, there is an increasing tendency to use diced cartilage grafts in rhinoplasty surgery for improving dorsum contour irregularities. This study was designed to compare graft resorption between three techniques of diced cartilage using surgical blade, electrical grinder and grater in rabbit model. METHODS Thirteen New Zealand rabbits were divided into three groups. Three 2×2 cm cartilage specimens were harvested from one of their ears. In group one, the cartilage was diced by use of No:11 surgical blade to o.5 to 1 mm cube pieces. In group two, an electrical grinder was used and in group three, a grater was applied. The grafts were placed in three subcutaneous pockets in the back of rabbits and after 12 weeks, the implants were removed and their weight and volume were recorded and were evaluated by histological techniques. RESULTS There was no difference between the three methods in the 3 groups for graft resorption. There was no change in the volume, but the weight showed a decrease in the control group. CONCLUSIONS As the histological results had no statistically difference between groups, we may recommend use of these two techniques in reconstructive and in aesthetic cases. PMID:25489525

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

    NASA Astrophysics Data System (ADS)

    Chernyshova, A. L.; Kolomiets, L. A.; Sinilkin, I. G.; Chernov, V. I.; Lyapunov, A. Yu.

    2016-08-01

    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.

  12. The iLappSurgery taTME app: a modern adjunct to the teaching of surgical techniques.

    PubMed

    Atallah, S; Brady, R R W

    2016-09-01

    Application-based technology has emerged as a method of modern information communication, and this has been applied towards surgical training and education. It allows surgeons the ability to obtain portable and instant access to information that is otherwise difficult to deliver. The iLappSurgery Foundation has recently launched the transanal total mesorectal excision educational application (taTME app) which provides a useful adjunct, especially for surgeons interested in mastery of the taTME technique and its principles. The article provides a detailed review of the application, which has achieved a large user-base since its debut in June, 2016. PMID:27503235

  13. Holospinal epidural abscess of the spinal axis: two illustrative cases with review of treatment strategies and surgical techniques.

    PubMed

    Smith, Gabriel A; Kochar, Arshneel S; Manjila, Sunil; Onwuzulike, Kaine; Geertman, Robert T; Anderson, James S; Steinmetz, Michael P

    2014-08-01

    Despite the increasing prevalence of spinal infections, the subcategory of holospinal epidural abscesses (HEAs) is extremely infrequent and requires unique management. Panspinal imaging (preferably MRI), modern aggressive antibiotic therapy, and prompt surgical intervention remain the standard of care for all spinal axis infections including HEAs; however, the surgical decision making on timing and extent of the procedure still remain ill defined for HEAs. Decompression including skip laminectomies or laminoplasties is described, with varied clinical outcomes. In this review the authors present the illustrative cases of 2 patients with HEAs who were treated using skip laminectomies and epidural catheter irrigation techniques. The discussion highlights different management strategies including the role of conservative (nonsurgical) management in these lesions, especially with an already identified pathogen and the absence of mass effect on MRI or significant neurological defects. Among fewer than 25 case reports of HEA published in the past 25 years, the most important aspect in deciding a role for surgery is the neurological examination. Nearly 20% were treated successfully with medical therapy alone if neurologically intact. None of the reported cases had an associated cranial infection with HEA, because the dural adhesion around the foramen magnum prevented rostral spread of infection. Traditionally a posterior approach to the epidural space with irrigation is performed, unless an extensive focal ventral collection is causing cord compression. Surgical intervention for HEA should be an adjuvant treatment strategy for all acutely deteriorating patients, whereas aspiration of other infected sites like a psoas abscess can determine an infective pathogen, and appropriate antibiotic treatment may avoid surgical intervention in the neurologically intact patient. PMID:25081960

  14. Surgical management of corneal limbal dermoids: retrospective study of different techniques and use of Mitomycin C

    PubMed Central

    Lang, S J; Böhringer, D; Reinhard, T

    2014-01-01

    Purpose We retrospectively studied the efficacy and safety of different surgical approaches to treating pediatric limbal dermoids with regard to intra and postoperative complications. Methods The data of 12 consecutive patients (14 eyes), who underwent monocentric surgery of a limbal demoid in the past 9 years, were retrospectively analyzed for intra and postoperative complications. Group one consists of eleven eyes: seven eyes with a bare-sclera deep lamellar excision of the dermoid and four eyes with an additional amniotic membrane transplantation subsequent to excision. Group two consists of three eyes: two eyes treated with Mitomycin C 0.02% over 2 min following the excision, and one eye treated with Mitomycin C and amniotic membrane transplantation after removal of the dermoid. Follow-up ranged from 2 to 53 months (median 17 months). Results Intraoperative complications did not occur in any of the patients. Postoperatively, all patients showed corneal reepithelialization within a week. Limbal stem cell deficiency with a pseudopterygium developed in four eyes, one treated with bare-sclera excision and the others with amniotic membrane transplantation. One pseudopterygium had to be removed surgically because of visual acuity deterioration. Not a single eye treated with Mitomycin C developed a pseudopterygium. Conclusions The transplantation of amniotic membrane following removal of a limbal dermoid cannot prevent the occurrence of a pseudopterygium. However, the use of Mitomycin C seems to have a protective effect. PMID:24858530

  15. Optimal Surgical Management of Severe Ischemic Mitral Regurgitation: To Repair or to Replace?

    PubMed Central

    Perrault, Louis P.; Moskowitz, Alan J.; Kron, Irving L.; Acker, Michael A.; Miller, Marissa A.; Horvath, Keith A.; Thourani, Vinod H.; Argenziano, Michael; D'Alessandro, David A.; Blackstone, Eugene H.; Moy, Claudia S.; Mathew, Joseph P.; Hung, Judy; Gardner, Timothy J.; Parides, Michael K.

    2013-01-01

    Background Ischemic mitral regurgitation (MR), a complication of myocardial infarction and coronary artery disease more generally, is associated with a high mortality rate and estimated to affect 2.8 million Americans. With 1-year mortality rates as high as 40%, recent practice guidelines of professional societies recommend repair or replacement, but there remains a lack of conclusive evidence supporting either intervention. The choice between therapeutic options is characterized by the trade-off between reduced operative morbidity and mortality with repair versus a better long-term correction of mitral insufficiency with replacement. The long-term benefits of repair versus replacement remain unknown, which has led to significant variation in surgical practice. Methods and Results This paper describes the design of a prospective randomized clinical trial to evaluate the safety and effectiveness of mitral valve repair and replacement in patients with severe ischemic mitral regurgitation. This trial is being conducted as part of the Cardiothoracic (CT) Surgical Trials Network. This paper addresses challenges in selecting a feasible primary endpoint, characterizing the target population (including the degree of MR), and analytical challenges in this high mortality disease. Conclusions The paper concludes by discussing the importance of information on functional status, survival, neurocognition, quality of life and cardiac physiology in therapeutic decision-making. PMID:22054660

  16. Technique to optimize magnetic response of gelatin coated magnetic nanoparticles.

    PubMed

    Parikh, Nidhi; Parekh, Kinnari

    2015-07-01

    The paper describes the results of optimization of magnetic response for highly stable bio-functionalize magnetic nanoparticles dispersion. Concentration of gelatin during in situ co-precipitation synthesis was varied from 8, 23 and 48 mg/mL to optimize magnetic properties. This variation results in a change in crystallite size from 10.3 to 7.8 ± 0.1 nm. TEM measurement of G3 sample shows highly crystalline spherical nanoparticles with a mean diameter of 7.2 ± 0.2 nm and diameter distribution (σ) of 0.27. FTIR spectra shows a shift of 22 cm(-1) at C=O stretching with absence of N-H stretching confirming the chemical binding of gelatin on magnetic nanoparticles. The concept of lone pair electron of the amide group explains the mechanism of binding. TGA shows 32.8-25.2% weight loss at 350 °C temperature substantiating decomposition of chemically bind gelatin. The magnetic response shows that for 8 mg/mL concentration of gelatin, the initial susceptibility and saturation magnetization is the maximum. The cytotoxicity of G3 sample was assessed in Normal Rat Kidney Epithelial Cells (NRK Line) by MTT assay. Results show an increase in viability for all concentrations, the indicative probability of a stimulating action of these particles in the nontoxic range. This shows the potential of this technique for biological applications as the coated particles are (i) superparamagnetic (ii) highly stable in physiological media (iii) possibility of attaching other drug with free functional group of gelatin and (iv) non-toxic. PMID:26152511

  17. Optimization technique for problems with an inequality constraint

    NASA Technical Reports Server (NTRS)

    Russell, K. J.

    1972-01-01

    General technique uses a modified version of an existing technique termed the pattern search technique. New procedure called the parallel move strategy permits pattern search technique to be used with problems involving a constraint.

  18. An optimal merging technique for high-resolution precipitation products: OPTIMAL MERGING OF PRECIPITATION METHOD

    SciTech Connect

    Shrestha, Roshan; Houser, Paul R.; Anantharaj, Valentine G.

    2011-04-01

    Precipitation products are currently available from various sources at higher spatial and temporal resolution than any time in the past. Each of the precipitation products has its strengths and weaknesses in availability, accuracy, resolution, retrieval techniques and quality control. By merging the precipitation data obtained from multiple sources, one can improve its information content by minimizing these issues. However, precipitation data merging poses challenges of scale-mismatch, and accurate error and bias assessment. In this paper we present Optimal Merging of Precipitation (OMP), a new method to merge precipitation data from multiple sources that are of different spatial and temporal resolutions and accuracies. This method is a combination of scale conversion and merging weight optimization, involving performance-tracing based on Bayesian statistics and trend-analysis, which yields merging weights for each precipitation data source. The weights are optimized at multiple scales to facilitate multiscale merging and better precipitation downscaling. Precipitation data used in the experiment include products from the 12-km resolution North American Land Data Assimilation (NLDAS) system, the 8-km resolution CMORPH and the 4-km resolution National Stage-IV QPE. The test cases demonstrate that the OMP method is capable of identifying a better data source and allocating a higher priority for them in the merging procedure, dynamically over the region and time period. This method is also effective in filtering out poor quality data introduced into the merging process.

  19. A Novel Surgical Technique for Thyroid Cancer with Intra-Cricotracheal Invasion: Windmill Resection and Tetris Reconstruction.

    PubMed

    Enomoto, Keisuke; Uchino, Shinya; Noguchi, Hitoshi; Enomoto, Yukie; Noguchi, Shiro

    2015-12-01

    The most effective treatment for thyroid cancer (TC) invading into the larynx and trachea is a complete surgical resection of the tumor, but currently employed techniques are less than ideal. We report a novel surgical technique, which we named Windmill resection and Tetris reconstruction, for patients with TC invading into the laryngeal lumen. We treated eight cases of TC with invasion into the laryngeal lumen by Windmill resection and Tetris reconstruction. We analyzed complications, clinical data, and pathological findings for all patients. Patients included one man and seven women (mean age 69 ± 10 years). Histopathology of TC indicated papillary cancer in five patients, poorly differentiated cancer in one patient, anaplastic cancer in one patient, and squamous cell carcinoma in one patient. Unilateral recurrent laryngeal nerve (RLN) palsy was confirmed preoperatively by laryngoscope in four patients, and none had bilateral RLN palsy. All patients underwent Windmill resection and Tetris reconstruction along with total thyroidectomy (three patients), subtotal thyroidectomy (three patients), and lobectomy (two patients). Neck dissection was performed in all patients. The average resected length of the larynx and trachea was 29 ± 6 mm. Air leakage at the suture line occurred in three patients; two required further surgery, while the third was closed by insertion of a Penrose drain. Postoperative RLN palsy occurred in five patients. Aspiration was observed in two patients and resolved within 4 weeks. Pneumonia, atelectasis, and pleural effusion occurred in some patients. No other complications, including hemorrhage, wound infection, or airway stenosis, occurred. There was no postoperative mortality and no recurrence at the anastomotic site. Two patients underwent permanent tracheostomy due to permanent bilateral RLN palsy. Two patients, one with anaplastic cancer and the other with poorly differentiated cancer, recurred 13 and 21 months after surgery

  20. A non-surgical uterine lavage technique in large cats intended for treatment of uterine infection-induced infertility.

    PubMed

    Hildebrandt, T B; Göritz, F; Boardman, W; Strike, T; Strauss, G; Jewgenow, K

    2006-10-01

    This paper presents the successful use of a non-surgical, transcervical uterine lavage technique for the treatment of uterine infection-induced infertility in three female large cats. We developed a non-surgical uterine lavage technique, which allowed repeated flushing of the uterine lumen and installation of therapeutic antibiotics. The entire procedure was performed under general anaesthesia (duration of anesthesia ranged from 40 to 70 min). It was successfully applied in a Sumatran tiger (Panthera tigris sumatrae), a Corbett tiger (Panthera tigris corbetti) and an Amur leopard (Panthera pardus orientalis). The tigers were treated only once, whereas the leopard received four uterine treatments, due to re-infection after mating. Decisions to conduct uterine treatments were based on detection of uterine fluid during previous transrectal ultrasound examinations. The catheter was guided into the vagina, with the aid of an endoscope, passing the urethra, and then into the uterus, with the aid of transrectal ultrasonography. Both uterine horns were separately flushed with approximately 300 mL of cell medium M199, followed by an antibiotic infusion. Upon ultrasonographic re-examination, the topical uterine treatments resulted in an apparent decline in the inflammatory and/or degenerative processes. The Corbett tiger had the most severe uterine alterations, in addition to an aseptic pyometra. As a result, she was treated 1 month prior to ovariohysterectomy (in order to reduce the surgical risk). The Sumatran tiger was artificially inseminated twice after hormone-induced estrus, and the Amur leopard expressed a spontaneous estrus and re-initiated mating behaviour. PMID:16530816

  1. Evaluation of coblation lingual tonsil removal technique for obstructive sleep apnea in Asians: preliminary results of surgical morbidity and prognosticators.

    PubMed

    Wee, Jee Hye; Tan, Kenglu; Lee, Woo-Hyun; Rhee, Chae-Seo; Kim, Jeong-Whun

    2015-09-01

    Retroglossal obstruction is one of the etiologies causing obstructive sleep apnea (OSA) and can be addressed by removing some tissues of the tongue base. However, because of its deep-seated location, its surgical removal is still challenging. Although coblation technique has been introduced, its efficacy and morbidity need further evaluation, particularly in Asians. This study aimed to assess its safety and effectiveness and to identify outcome prognosticators. Forty-seven OSA patients who underwent coblation lingual tonsil removal were included. Retroglossal obstruction was confirmed by drug-induced sleep videofluoroscopy. Attended full-night polysomnography was performed twice; before and 6 months after surgery in 27 patients. The tongue base was fully exposed with three deep-seated traction sutures, visualized with a 30° or 70° endoscope, and ablated using a coblator. Surgical success was defined with postoperative apnea hypopnea index (AHI) <20 and reduction >50 %. Postoperative morbidities were evaluated. Demographic and polysomnographic parameters between success and failure groups were compared. None of the patients had immediate postoperative hemorrhage. Postoperatively, one patient had delayed hemorrhage and one patient severe respiratory difficulty. Taste loss, tongue dysmotility, dental injury or severe oropharyngeal stricture were absent. A mean AHI decreased from 37.7 ± 18.6 to 18.7 ± 14.8/h (P < 0.001). The success rate was 55.6 %. Their mean minimal oxygen saturation was significantly lower (P = 0.004) in the failure group. Coblation lingual tonsil removal technique showed minimal morbidity and favorable outcome in Koreans. The surgical outcome might be associated with the severity of single respiratory events. PMID:25323152

  2. The Future of Rheumatoid Arthritis and Hand Surgery - Combining Evolutionary Pharmacology and Surgical Technique

    PubMed Central

    M, Malahias; H, Gardner; S, Hindocha; A, Juma; Khan, W

    2012-01-01

    Rheumatoid arthritis is a systemic autoimmune disease of uncertain aetiology, which is characterized primarily by synovial inflammation with secondary skeletal destructions. Rheumatoid Arthritis is diagnosed by the presence of four of the seven diagnostic criteria, defined by The American College of Rheumatology. Approximately half a million adults in the United Kingdom suffer from rheumatoid arthritis with an age prevalence between the second and fourth decades of life; annually approximately 20,000 new cases are diagnosed. The management of Rheumatoid Arthritis is complex; in the initial phase of the disease it primarily depends on pharmacological management. With disease progression, surgical input to correct deformity comes to play an increasingly important role. The treatment of this condition is also intimately coupled with input from both the occupational therapists and physiotherapy. PMID:22423304

  3. Arthroscopic contact Nd:YAG laser meniscectomy: surgical technique and clinical follow-up

    NASA Astrophysics Data System (ADS)

    O'Brien, Stephen J.; Miller, Drew V.; Fealy, Stephen V.; Gibney, Mary A.; Kelly, Anne M.

    1991-05-01

    Fifteen patients were studied prospectively as a pilot study to evaluate the safety and efficacy of the contact Neodynium: Yttrium Aluminum Garnet (Nd:YAG) laser in performing arthroscopic meniscal resection in a saline medium, (Surgical Laser Technologies; Malverne, PA). All fifteen patients were rated as having clinically excellent results based on pain relief, wound healing, and post-operative swelling. Although there was increased time involved with setting up and calibrating the laser, there was not an increase in time for meniscal resection. In addition, the decreased need for secondary trimming and increased accessibility to the posterior horns of the menisci represent advantages over conventional instruments. Based on the findings, arthroscopic contact Nd:YAG laser surgery is a safe and effective clinical tool for meniscal resection which may, with increased technological advancements and cost reduction, replace standard instrumentation.

  4. Surgical Simulation

    PubMed Central

    Sutherland, Leanne M.; Middleton, Philippa F.; Anthony, Adrian; Hamdorf, Jeffrey; Cregan, Patrick; Scott, David; Maddern, Guy J.

    2006-01-01

    Objective: To evaluate the effectiveness of surgical simulation compared with other methods of surgical training. Summary Background Data: Surgical simulation (with or without computers) is attractive because it avoids the use of patients for skills practice and provides relevant technical training for trainees before they operate on humans. Methods: Studies were identified through searches of MEDLINE, EMBASE, the Cochrane Library, and other databases until April 2005. Included studies must have been randomized controlled trials (RCTs) assessing any training technique using at least some elements of surgical simulation, which reported measures of surgical task performance. Results: Thirty RCTs with 760 participants were able to be included, although the quality of the RCTs was often poor. Computer simulation generally showed better results than no training at all (and than physical trainer/model training in one RCT), but was not convincingly superior to standard training (such as surgical drills) or video simulation (particularly when assessed by operative performance). Video simulation did not show consistently better results than groups with no training at all, and there were not enough data to determine if video simulation was better than standard training or the use of models. Model simulation may have been better than standard training, and cadaver training may have been better than model training. Conclusions: While there may be compelling reasons to reduce reliance on patients, cadavers, and animals for surgical training, none of the methods of simulated training has yet been shown to be better than other forms of surgical training. PMID:16495690

  5. Comparison of a CO2 (Carbon Dioxide) Laser and Tissue Glue with Conventional Surgical Techniques in Circumcision

    PubMed Central

    Mungnirandr, Akkrapol; Wiriyakamolphan, Suwanna; Ruangtrakool, Ravit; Ngerncham, Monawat; Tumrongsombutsakul, Sureerat; Leumcharoen, Bungorn

    2015-01-01

    Introduction: CO2 (Carbon Dioxide) laser application in circumcision, for cutting and coagulation, has been reported to have excellent results. Also, tissue glue has been reported to have advantages over sutures for approximation of wound edges. Most previous studies focused on comparisons between CO2 laser and scalpel, or between tissue glue and sutures. This study prospectively compared the results and complications CO2 laser and tissue glue, with standard surgical techniques in circumcision. Methods: Thirty boys were prospectively divided into two groups. Group 1 (n = 17) underwent circumcision by scalpel with approximation of the wound edges using chromic catgut sutures. Group 2 (n = 13) underwent circumcision with CO2 laser and approximation of the wound edges using tissue glue. Patient age, indications for surgery, operative time, wound swelling, bleeding, wound infection, local irritation, pain score, and cosmetic appearance were recorded. Results: Group 1 had a significantly longer operative time (P= 0.011), higher rate of local irritation (P= 0.016), and poorer cosmetic appearance (P< 0.001) than group 2. Bleeding only occurred in one patient in group 1. There were no significant differences in pain score, wound infection rate, or cost of surgery between the two groups. Conclusions: CO2 laser and tissue glue have advantages over standard surgical techniques in circumcision, with a significantly shorter operative time, lower rate of local irritation, and better cosmetic appearance. The cost of surgery is similar between the two groups. PMID:25699165

  6. Two-flap palatoplasty: description of the surgical technique and reporting of results at a single center.

    PubMed

    Koudoumnakis, Emmanouel; Vlastos, Ioannis M; Parpounas, Kostas; Houlakis, Michael

    2012-03-01

    Two-flap palatoplasty is commonly used to treat cleft palate defects, but only a few reports on outcomes have been published in the literature. We conducted a retrospective analysis of 257 cases of cleft palate treated with two-flap palatoplasty at a single center in Greece over a 13-year period. Our outcomes data included surgical complication rates, the results of speech assessments, midface development, and other parameters. We found a low rate of short- and long-term complications that required revision surgery, such as symptomatic fistula (5.4%) and velopharyngeal insufficiency (5.3%). Speech outcomes in relation to intelligibility, hypernasality, and nasal emissions were satisfactory in 70 to 86% of patients. Dental arch relationships, as estimated by the 5-Year-Olds Index, were judged to be either good or excellent in 62% of those evaluated. A considerable proportion of patients (45%) who had otitis media with effusion experienced a spontaneous resolution without the use of tympanostomy tubes 2 to 8 months after their operation. We conclude that two-flap palatoplasty is an effective procedure that warrants further attention. We describe the surgical technique in detail. Our technique includes a modified intravelar veloplasty that incorporates near-total muscle retropositioning. PMID:22430346

  7. Novel Endoscopic and Surgical Techniques for Treatment of Morbid Obesity: A Glimpse into the Future.

    PubMed

    Davis, Matthew; Kroh, Matthew

    2016-08-01

    The burden of obesity and weight-related comorbid disease is significant. Existing laparoscopic techniques show excellent efficacy and safety. New endoscopic and laparoscopic procedures offer different approaches, as primary and revisional techniques, to treat obesity and associated metabolic disease. PMID:27473806

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

    PubMed

    Patel, D M; Patel, M 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) full factorial design was applied to investigate the combined effect of 2 formulation variables: amount of menthol and crospovidone. The results of multiple regression analysis indicated that for obtaining fast dissolving tablets; optimum amount of menthol and higher percentage of crospovidone should be used. A surface response plots are also presented to graphically represent the effect of the independent variables on the percentage friability and disintegration time. The validity of a generated mathematical model was tested by preparing a checkpoint batch. Sublimation of menthol from tablets resulted in rapid disintegration as compared with the tablets prepared from granules that were exposed to vacuum. The optimized tablet formulation was compared with conventional marketed tablets for percentage drug dissolved in 30 min (Q(30)) and dissolution efficiency after 30 min (DE(30)). From the results, it was concluded that fast dissolving tablets with improved etoricoxib dissolution could be prepared by sublimation of tablets containing suitable subliming agent. PMID:20390084

  9. Optimization of Fast Dissolving Etoricoxib Tablets Prepared by Sublimation Technique

    PubMed Central

    Patel, D. M.; Patel, M. 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 32 full factorial design was applied to investigate the combined effect of 2 formulation variables: amount of menthol and crospovidone. The results of multiple regression analysis indicated that for obtaining fast dissolving tablets; optimum amount of menthol and higher percentage of crospovidone should be used. A surface response plots are also presented to graphically represent the effect of the independent variables on the percentage friability and disintegration time. The validity of a generated mathematical model was tested by preparing a checkpoint batch. Sublimation of menthol from tablets resulted in rapid disintegration as compared with the tablets prepared from granules that were exposed to vacuum. The optimized tablet formulation was compared with conventional marketed tablets for percentage drug dissolved in 30 min (Q30) and dissolution efficiency after 30 min (DE30). From the results, it was concluded that fast dissolving tablets with improved etoricoxib dissolution could be prepared by sublimation of tablets containing suitable subliming agent. PMID:20390084

  10. Optimizing physician access to surgical intensive care unit laboratory information through mobile computing.

    PubMed Central

    Strain, J. J.; Felciano, R. M.; Seiver, A.; Acuff, R.; Fagan, L.

    1996-01-01

    Approximately 30 minutes of computer access time are required by surgical residents at Stanford University Medical Center (SUMC) to examine the lab values of all patients on a surgical intensive care unit (ICU) service, a task that must be performed several times a day. To reduce the time accessing this information and simultaneously increase the readability and currency of the data, we have created a mobile, pen-based user interface and software system that delivers lab results to surgeons in the ICU. The ScroungeMaster system, loaded on a portable tablet computer, retrieves lab results for a subset of patients from the central laboratory computer and stores them in a local database cache. The cache can be updated on command; this update takes approximately 2.7 minutes for all ICU patients being followed by the surgeon, and can be performed as a background task while the user continues to access selected lab results. The user interface presents lab results according to physiologic system. Which labs are displayed first is governed by a layout selection algorithm based on previous accesses to the patient's lab information, physician preferences, and the nature of the patient's medical condition. Initial evaluation of the system has shown that physicians prefer the ScroungeMaster interface to that of existing systems at SUMC and are satisfied with the system's performance. We discuss the evolution of ScroungeMaster and make observations on changes to physician work flow with the presence of mobile, pen-based computing in the ICU. PMID:8947778

  11. Nasogastric tube placement into the hepaticojejunostomy anastomosis in pancreaticoduodenectomy: a simple surgical technique for prevention of bile leak.

    PubMed

    Kaya, Bulent; Ozcabi, Yetkin; Tasdelen, Iksan; Onur, Ender; Memisoglu, Kemal

    2016-05-01

    Hepaticojejunostomy is an important part of many surgical procedures including pancreaticoduodenectomy. Biliary leakage from hepaticojejunostomy may be associated with intraabdominal abscess formation, biliary peritonitis, and even mortality. A 72-year-old female patient was admitted to our hospital with obstructive jaundice. After initial evaluation, she was diagnosed with distal common bile duct obstruction without accurate diagnosis. Before planned pancreaticoduodenectomy, biliary drainage with a T-tube was performed due to the presence of cholangitis. After the first operation, pancreaticoduodenectomy was performed. Postinflammatory changes around the hilar region made the hepaticojejunostomy risky. A bilio-digestive anastomosis was performed using a new technique. A nasogastric tube was placed into the common bile duct proximal to the anastomosis. The postoperative course of the patient was uneventful. The use of a nasogastric tube as a stent in risky hepaticojejunostomies is a simple technique that can be beneficial. PMID:27212998

  12. Nasogastric tube placement into the hepaticojejunostomy anastomosis in pancreaticoduodenectomy: a simple surgical technique for prevention of bile leak

    PubMed Central

    Ozcabi, Yetkin; Tasdelen, Iksan; Onur, Ender; Memisoglu, Kemal

    2016-01-01

    Hepaticojejunostomy is an important part of many surgical procedures including pancreaticoduodenectomy. Biliary leakage from hepaticojejunostomy may be associated with intraabdominal abscess formation, biliary peritonitis, and even mortality. A 72-year-old female patient was admitted to our hospital with obstructive jaundice. After initial evaluation, she was diagnosed with distal common bile duct obstruction without accurate diagnosis. Before planned pancreaticoduodenectomy, biliary drainage with a T-tube was performed due to the presence of cholangitis. After the first operation, pancreaticoduodenectomy was performed. Postinflammatory changes around the hilar region made the hepaticojejunostomy risky. A bilio-digestive anastomosis was performed using a new technique. A nasogastric tube was placed into the common bile duct proximal to the anastomosis. The postoperative course of the patient was uneventful. The use of a nasogastric tube as a stent in risky hepaticojejunostomies is a simple technique that can be beneficial. PMID:27212998

  13. Influence of two different surgical techniques on the difficulty of impacted lower third molar extraction and their post-operative complications

    PubMed Central

    Ohanyan, Ani; Kechagias, Nikos; Tsekos, Antonis; Vahtsevanos, Konstantinos

    2015-01-01

    Background Post-operative complications of various degrees of severity are commonly observed in third molar impaction surgery. For this reason, a surgical procedure that decreases the trauma of bone and soft tissues should be a priority for surgeons. In the present study, we compare the efficacy and the post-operative complications of patients to whom two different surgical techniques were applied for impacted lower third molar extraction. Material and Methods Patients of the first group underwent the classical bur technique, while patients of the second group underwent another technique, in which an elevator was placed on the buccal surface of the impacted molar in order to luxate the alveolar socket more easily. Results Comparing the two techniques, we observed a statistically significant decrease in the duration of the procedure and in the need for tooth sectioning when applying the second surgical technique, while the post-operative complications were similar in the two groups. We also found a statistically significant lower incidence of lingual nerve lesions and only a slightly higher frequency of sharp mandibular bone irregularities in the second group, which however was not statistically significant. Conclusions The results of our study indicate that the surgical technique using an elevator on the buccal surface of the tooth seems to be a reliable method to extract impacted third molars safely, easily, quickly and with the minimum trauma to the surrounding tissues. Key words:Mandibular third molar, impacted, surgical technique, extraction, elevator. PMID:26116843

  14. A useful surgical technique for retrieval of a broken guide pin in the midfoot.

    PubMed

    Roy, Shuvendu Prosad; Lim, Chin Tat; Tan, Ken Jin

    2014-01-01

    Perioperative instrument breakage is not an infrequent occurrence, even for experienced surgeons. The most commonly reported instrument breaks in orthopedic procedures are drill bits, followed by Kirschner wires and cannulated guide pins. The reasons for failure include improper technique and repetitive use. The retrieval of broken hardware can be technically challenging, particularly if the fragment has become embedded in bone. Retrieval methods have been described for cannulated guide pin fragments in the hip; however, no specific techniques have been described for the retrieval of guide pin fragments embedded in the bones of the foot. In the present report, we describe a technique we have found useful for retrieval of a guide pin fragment that had broken off during a Lisfranc fracture repair 6 weeks earlier. The technique was used in a delayed situation; however, we believe it would be even easier to use during an intraoperative breakage. PMID:23871172

  15. Remifentanil-based anesthesia versus a propofol technique for otologic surgical procedures.

    PubMed

    Jellish, W S; Leonetti, J P; Avramov, A; Fluder, E; Murdoch, J

    2000-02-01

    Otologic procedures require a still surgical field and are associated with a 50% incidence of emetic symptoms. Propofol reduces nausea and vomiting but not intraoperative movement. This study compares a remifentanil/propofol anesthetic to a propofol/fentanyl combination to determine which provides the best perioperative conditions for otologic microsurgery. Eighty healthy patients were randomly assigned to receive one of the anesthetic combinations. Demographic data, hemodynamic variables, movement, and bispectral index monitoring values in addition to anesthetic emergence, nausea, vomiting, pain, and other recovery variables were compared between groups with appropriate statistical methods. Both groups were similar. Times to eye opening (7.7 +/- 0.7 vs 12.4 +/- 1.2 minutes) and extubation (9.8 +/- 0.9 vs 12.4 +/- 1.0 minutes) were shorter with remifentanil. This group also had lower hemodynamic variables and movement (23% vs 65%) under anesthesia. Postoperative pain was mild in both groups, but remifentanil patients had more than the propofol group. All other postoperative parameters were similar. Remifentanil-based anesthesia produces better hemodynamic stability, less movement, and faster emergence after otologic surgery, with propofol's antiemetic effect, for the same cost. PMID:10652394

  16. Arthroscopic contact Nd:YAG laser meniscectomy: basic science, surgical technique, and clinical follow up

    NASA Astrophysics Data System (ADS)

    O'Brien, Stephen J.; Fealy, Stephen V.; Gibney, Mary A.; Miller, Drew V.; Kelly, Anne M.

    1990-06-01

    Recent basic science studies (5) have provided a scientific foundation for the use of the Contact Nd:YAG Laser as an arthroscopic tool for xneniscal resection and acroxnioplasty of the shoulder in a saline medium. This study prospectively evaluates the results of a three stage laboratory investigation as well as the clinical results of arthroscopic xneniscal resection. Fifteen patients with meniscal tears underwent subtotal meniscectomies utilizing a Contact Nd:YAG Laser (Surgical Laser Technologies; Malvern, Pennsylvania) . This was done in a saline medium with an average laser wattage of 25 W, (range 20 W to 30 W). Patients were evaluated postoperatively with reference to subjective and objective parameters at one week and four weeks postoperatively. Patients were evaluated with regard to wound healing, intraarticular swelling and pain. Assessment of technical parameters such as ease of resection, time of resection and instrument access were compared to conventional instruments. All fifteen patients were rated as having clinically excellent results based on pain relief, wound healing and swelling. In addition, although there was increased time with setting up the laser and calibrating it, there was not an increase in time for meniscal resection. Little, or no, secondary "trimmuning" was necessary with the laser. Increased accessibility was noted due to the small size of the laser. Arthroscopic Contact Nd:YAG Laser surgery is a safe and effective tool for menisca]. resection and coagulation in arthroscopic acromioplasties. It provides significant advantages over conventional cutting instruments with regard to accessibility and reduced need for secondary instruments.

  17. Laparoscopic totally extraperitoneal (TEP) hernioplasty using two trocars: anatomical landmarks and surgical technique

    PubMed Central

    IUAMOTO, Leandro Ryuchi; KATO, Juliana Mika; MEYER, Alberto; BLANC, Pierre

    2015-01-01

    Background Among endoscopic hernioplasties, totally extraperitoneal (TEP) and transabdominal preperitoneal (TAPP) approach are widely accepted alternatives to open surgery, both providing less postoperative pain, hospital length of stay and early return to work. Classical TEP technique requires three skin incisions for placement of three trocars in the midline or in triangulation. Aim To describe a technique using only two trocars for laparoscopic total extraperitoneal for inguinal hernia repair. Method Extraperitoneal access: place two regular trocars on the midline. The 10 mm is inserted into the subcutaneous in horizontal direction after a transverse infra-umbilical incision and then elevated at 60º angle. The 5 mm trocar is inserted at the same level of the pubis with direct vision. Preperitoneal space dissection: introduction 0º optical laparoscope through the infra-umbilical incision for visualization and preperitoneal dissection; insufflation pressure must be below 12 mmHg. Dissection of some anatomical landmarks: pubic bone, arcuate line and inferior epigastric vessels. Exposure of "triangle of pain" and "triangle of doom". Insertion through the 10 mm trocar polypropylene mesh of 10x15 cm to cover the hernia sites. Peritoneal sac and the dorsal edge of the mesh are repositioned in order to avoid bending or mesh displacement. It is also important to remember that the drainage is not necessary. Results The 2-port TEP required less financial costs than usual because it is not necessary an auxiliary surgeon to perform the technique. Trocars, suturing material and wound dressing were spared in comparison to the classical technique. Besides, there were only two incisions, which provides a better plastic result and less postoperative pain. Conclusion The TEP technique using two trocars is an alternative technique which improves cosmetic and financial outcomes. PMID:26176249

  18. New technique for treating abdominal surgical site infection using CT woundgraphy and NPWT: A case report

    PubMed Central

    Ito, Eisaku; Yoshida, Masashi; Nakashima, Keigo; Suzuki, Norihiko; Imakita, Tomonori; Tsutsui, Nobuhiro; Ohdaira, Hironori; Kitajima, Masaki; Suzuki, Yutaka

    2016-01-01

    Introduction Negative pressure wound therapy (NPWT) for abdominal surgical site infection (SSI) is becoming increasingly common, although enterocutaneous fistula (ECF) has been reported as a complication. To avoid ECF, we used computed tomography (CT) woundgraphy to evaluate the relationship between the wound and the intestine, and then safely treated the abdominal SSI with NPWT. Case presentation Following a laparoscopic intersphincteric resection for low rectal neuroendocrine tumor and covering ileostomy, a 59-year-old woman underwent stoma closure. Six days after surgery, we diagnosed SSI. We suspected ECF, because the wound was deep and the pus resembled enteric fluid. However, CT woundgraphy showed that the wound was separated from the abdominal cavity and the intestine by the abdominal rectus muscle. Accordingly, we performed NPWT. SSI was cured and the wound was well granulated. Twenty-three days after surgery, the patient was discharged. Eventually, the wound was completely epithelialized. Discussion Although successful NPWT has been reported for open abdominal wounds, ECF is a common complication. ECF can be prevented by separating the wound from the intestine by the omentum or muscle fascia, protecting the intestinal serosa during surgery, and applying low vacuum pressure. The relationships among the wound, the fascia, and the intestine must be evaluated before abdominal SSI treatment. One good method is CT woundgraphy, which evaluates wound extent and depth, closure of muscle fascia, and the relationship between the wound and the intestine. Conclusion We report a case of CT woundgraphy before NPWT for abdominal SSI. CT woundgraphy is a good candidate for evaluating wound condition. PMID:27002290

  19. Surgical therapy of Peyronie's disease by partial plaque excision and grafting with collagen fleece: feasibility study of a new technique.

    PubMed

    Hatzichristodoulou, G; Gschwend, J E; Lahme, S

    2013-09-01

    Surgery is gold-standard for correction of Peyronie's curvature. Grafting is preferred in advanced deviations. We present our novel surgical technique and early results of grafting with collagen fleece. Patients with stable Peyronie's disease (PD) were included. Grafting was performed by a ready-to-use collagen fleece coated with tissue sealant (TachoSil, Nycomed, Konstanz, Germany), following partial plaque excision/incision. Results of correction were documented by artificial erection. In all, n=70 consecutive patients underwent surgery. Mean patient age was 56.4 years (range: 33-72); 88.6% of patients had dorsal deviation, 11.4% lateral or ventral deviation. Grafting after partial plaque excision was performed in 61 patients (87.1%), after plaque incision in 2 (2.9%) patients. In the former patients, mean operative time was 94.2 min (range: 65-165). Totally straightness was achieved in 83.6%. Three patients required surgical drainage because of subcutaneous haematoma formation. After mean early follow-up of 5.2 days (range: 2-15), glans sensation was normal in 56 patients (91.8%). Seven patients (10.0%) underwent Nesbit procedure alone. Grafting by collagen fleece in PD is feasible and promising. Major advantages are decreased operative times and easy application. Moreover, an additional haemostatic effect is provided. However, long-term clinical outcomes are necessary to confirm these encouraging findings. PMID:23446807

  20. Precise control of caval and hepatic vessels: Surgical technique to treat level III caval thrombus concomitant to renal cell carcinoma

    PubMed Central

    Chen, Ming; Xu, Bin; Liu, Ning; Jiang, Hua; Wang, Yiduo; Yang, Yu; Zhang, Xiaowen; Sun, Chao; Liu, Jing; Zhu, Weidong; Chen, Shuqiu

    2015-01-01

    Introduction: We investigated the surgical techniques, safety, and prevention of complications of nephrectomy and removal of tumour thrombus for treating level III inferior vena cava (IVC) concomitant to renal cell carcinoma (RCC). We did this by precise controlling IVC and hepatic vessels without a vascular bypass. Methods: In this series, we included 5 patients with level III IVC tumour thrombus below the hepatic vein concomitant to RCC. After precisely controlling the IVC and hepatic vessels, we then removed the thrombus en bloc with the renal vein. Blood loss volume, IVC clamping time, hypotension time, resuscitation, cardiocerebrovascular complications, and postoperative organ dysfunction were observed. Results: Surgery was successfully performed without perioperative death. Blood loss volume was 900 to 1500 mL, operation time was 165 to 250 minutes, vascular clamping time was 8 to 12 minutes, and intraoperative hypotension time was 9 to 12 minutes. Serious perioperative complications were not observed. Local recurrence was not observed during the 9 to 24 months of follow-up. One patient exhibited disease-free survival, 3 developed lung or liver metastasis, and 1 died 11 months after surgery. Conclusion: Precise control of IVC and hepatic pedicle vessels, without vascular bypass, is a safe and effective surgical treatment for level III tumor thrombus below the hepatic vein concomitant to RCC. The procedure was conducted without increased risks of intraoperative hypotensive shock, difficult resuscitation, pulmonary embolism, and multiple organ dysfunctions. PMID:26600890

  1. Arthroscopic Labrum Reconstruction in the Hip Using the Indirect Head of Rectus Femoris as a Local Graft: Surgical Technique.

    PubMed

    Sharfman, Zachary T; Amar, Eyal; Sampson, Thomas; Rath, Ehud

    2016-04-01

    The importance of the acetabular labrum has been well documented for the health and function of the hip joint. Labral reconstruction has proven effective but often requires the use of a cadaveric allograft or auto graft from the fascia lata or gracilis. The indirect head of the rectus femoris is in close proximity with the anterior superior acetabulum, which is the most common site of labral tears. Using the indirect head of the rectus femoris as a local graft minimizes surgical invasiveness by mitigating the need to harvest the graft from a different location, in case of an autograft, and by minimizing donor site morbidity and damage to local tissues. The graft is harvested and fixed to the acetabular rim through the same arthroscopic portals. Hip labral reconstruction using the reflected head of the rectus femoris tendon is a minimally invasive surgical procedure that restores stability to the hip joint, is applicable in all patients undergoing hip labral reconstruction, and offers decreased tissue morbidity compared with other grafting techniques. PMID:27462534

  2. Surgical technique: coupling of intrastromal corneal ring segments for ectatic corneal disorders in eye bank corneas

    PubMed Central

    Moshirfar, Majid; Hsu, Maylon; Khalifa, Yousuf M

    2011-01-01

    The management of corneal ectasia is evolving, with intrastromal corneal ring segments playing an important role in delaying or eliminating the need for penetrating keratoplasty. This paper describes a modification in the implantation technique of intrastromal corneal ring segments that allows for coupling of the two segments with suture, affording more structural support. PMID:22034567

  3. Type 2 fractures of the distal clavicle: a new surgical technique.

    PubMed

    Goldberg, J A; Bruce, W J; Sonnabend, D H; Walsh, W R

    1997-01-01

    Neer type 2 fractures of the distal clavicle have a high rate of nonunion and delayed union. In this series nine cases of coracoclavicular ligament reconstruction with Dacron graft material led to union at the fracture site. All patients had no symptoms and returned to full activity. This technique allows for stable fixation with early mobilization and return to work and sports. PMID:9285878

  4. Implementation of a Surgical Safety Checklist: Interventions to Optimize the Process and Hints to Increase Compliance

    PubMed Central

    Sendlhofer, Gerald; Mosbacher, Nina; Karina, Leitgeb; Kober, Brigitte; Jantscher, Lydia; Berghold, Andrea; Pregartner, Gudrun; Brunner, Gernot; Kamolz, Lars Peter

    2015-01-01

    Background A surgical safety checklist (SSC) was implemented and routinely evaluated within our hospital. The purpose of this study was to analyze compliance, knowledge of and satisfaction with the SSC to determine further improvements. Methods The implementation of the SSC was observed in a pilot unit. After roll-out into each operating theater, compliance with the SSC was routinely measured. To assess subjective and objective knowledge, as well as satisfaction with the SSC implementation, an online survey (N = 891) was performed. Results During two test runs in a piloting unit, 305 operations were observed, 175 in test run 1 and 130 in test run 2. The SSC was used in 77.1% of all operations in test run 1 and in 99.2% in test run 2. Within used SSCs, completion rates were 36.3% in test run 1 and 1.6% in test run 2. After roll-out, three unannounced audits took place and showed that the SSC was used in 95.3%, 91.9% and 89.9%. Within used SSCs, completion rates decreased from 81.7% to 60.6% and 53.2%. In 2014, 164 (18.4%) operating team members responded to the online survey, 160 of which were included in the analysis. 146 (91.3%) consultants and nursing staff reported to use the SSC regularly in daily routine. Conclusion These data show that the implementation of new tools such as the adapted WHO SSC needs constant supervision and instruction until it becomes self-evident and accepted. Further efforts, consisting mainly of hands-on leadership and training are necessary. PMID:25658317

  5. [OPTIMIZATION OF THE SURGICAL TREATMENT RESULTS IN CONOTRUNCAL CARDIAC FAILURES IN LARGE AORTO-PULMONARY COLLATERAL ARTERIES].

    PubMed

    Bablyak, O D

    2015-09-01

    The results of surgical treatment of 83 patients, suffering conotruncal cardiac failures and large aorto-pulmonary collateral arteries, were analyzed. In 2007 - 2014 yrs a radical correction of the failure (RCF) was performed in 53 (64%) of them. RCF was achieved, using three surgical approaches. The algorithm of a surgical approach choice was introduced, guaranteeing the operation time shortening and artificial blood circulation application, have improved the course of early postoperative period. It was proved, that improvement of surgical results is possible, if a correct surgical tactic choosed and surgical approaches rationally applied. PMID:26817084

  6. Minimally invasive surgical technique integrating multiple procedures with large specimen extraction via inguinal hernia orifice

    PubMed Central

    Mani, Vishnu R.; Ahmed, Leaque

    2015-01-01

    While laparoscopic surgery can be performed using small skin incisions, any resected specimen must still be able to fit through these opening. For procedures, such as cholecystectomies and appendectomies, this is not usually a problem; however, for large specimens such as bowel or large tumors, this becomes problematic. Currently, the standard technique is to attempt piecemeal removal of the specimen or enlarge one of the laparoscopic incisions, effectively creating a mini laparotomy. Creating a larger incision adds many of the drawbacks of open laparotomy and should be avoided whenever possible. In this article, we present a new technique of combining the repair of an inguinal hernia, umbilical hernia with a duodenal tumor resection in order to extract the specimen through the inguinal hernia orifice. PMID:26703927

  7. “Bird-Wing” abdominal phalloplasty: A novel surgical technique for penile reconstruction

    PubMed Central

    Bajpai, Minu

    2013-01-01

    Aim: To describe a technique of phalloplasty that is devoid of donor site scarring and suitable for urethral inlay and penile prosthesis in subsequent stages in cases of aphallia. Materials and Methods: Four patients with various disorders of sex development with 46 XY and severe penile deficiency, including one with complete androgen insensitivity syndrome who was initially raised as female, have been operated using a “Bird Wing” lower abdominal skin crease incision. Results: The patients’ age ranged from 6 to 17 years with preoperative stretched penile lengths between 1 and 2.5 cm. Phallic sizes between 7.5 and 12.5 cm was achieved leaving the donor site unremarkable with lower abdominal skin crease linear scar and excellent postoperative recovery. Conclusions: This phalloplasty technique can be utilized as a definitive procedure in many situations of penile insufficiency. Subsequent stages of urethral repair and insertion of penile prosthesis can be easily added. PMID:23798805

  8. Liver transplantation in children from living related donors. Surgical techniques and results.

    PubMed Central

    Broelsch, C E; Whitington, P F; Emond, J C; Heffron, T G; Thistlethwaite, J R; Stevens, L; Piper, J; Whitington, S H; Lichtor, J L

    1991-01-01

    three procedures, in which a full left hepatectomy was performed. After alteration of the procedure into a left lateral segmentectomy, no complications were encountered. The left lateral segmentectomy presents minimal surgical trauma to the liver and should remain the primary approach for obtaining a liver graft from a living donor. For children, transplantation of a left lateral segment from a live donor provides a new way of providing a transplant of appropriate size and with good function. The success of this program has led to the acceptance of LRT for general clinical application in the authors' institution. PMID:1953097

  9. Two-stage closed sinus lift: a new surgical technique for maxillary sinus floor augmentation.

    PubMed

    Krasny, Kornel; Krasny, Marta; Kamiński, Artur

    2015-12-01

    Bone tissue atrophy may constitute a relative contraindication for implantation. The methods used in reconstruction of the alveolar ridge within the lateral section of the maxilla have been well known but not perfect. Presentation of the two-stage, closed sinus lift technique as well as efficacy evaluation of reconstruction of the alveolar ridge in the maxilla within its vertical dimension with the use of this technique. The total procedure was performed in 26 out of 28 patients qualified for the study. The height of the alveolar ridge at the site of the planned implantation was no <3 mm, the width of the ridge was no <5 mm. During the treatment stage 1 the sinus lift was performed for the first time. The created hollow was filled with allogeneic granulate. After 3-6 months stage 2 was performed consisting in another sinus lift with simultaneous implantation. The treatment was completed with prosthetic restoration after 6 months of osteointegration. In 24 out of 26 cases stage 1 was completed with the average ridge height of 7.2 mm. In stage 2, simultaneously with the second sinus lift, 26 implants were placed and no cases of sinusitis were found. In the follow-up period none of the implants were lost. The presented method is efficient and combines the benefits of the open technique-allowing treatment in cases of larger reduction of the vertical dimension and the closed technique-as it does not require opening of the maxillary sinus. PMID:25754426

  10. Shoulder arthroplasty in osteoarthritis: current concepts in biomechanics and surgical technique

    PubMed Central

    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

  11. Lateral high abdominal ovariopexy: an original surgical technique for protection of the ovaries during curative radiotherapy for Hodgkin's disease

    SciTech Connect

    Gaetini, A.; De Simone, M.; Urgesi, A.; Levis, A.; Resegotti, A.; Ragona, R.; Anglesio, S.

    1988-09-01

    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.

  12. Assessment of surgical outcomes of limbal transplantation using simple limbal epithelial transplantation technique in patients with total unilateral limbal deficiency.

    PubMed

    Queiroz, Ana Gabriela; Barbosa, Martina Maria Oiticica; Santos, Myrna Serapião; Barreiro, Telma Pereira; Gomes, José Álvaro Pereira

    2016-04-01

    This study aimed to evaluate the effectiveness of the novel simple limbal epithelial transplantation (SLET) technique, which reduces the risk of iatrogenic limbal stem cell deficiency in the donor eye. Four patients with total unilateral limbal stem cell deficiency received a limbal graft, measuring 4 mm × 2 mm, from the contralateral healthy eye in a single surgical procedure. The graft was divided into 10-20 pieces and distributed on the corneal surface. At 6-month follow-up, a completely avascular corneal epithelial surface was obtained in two patients, and there was improvement in visual acuity in one patient. The limbal grafts did not adhere to the cornea in one patient. No serious complications related to the surgery were observed in this study. PMID:27224077

  13. Reversal of Peroneal Tenodesis With Allograft Reconstruction of the Peroneus Brevis and Longus: Case Report and Surgical Technique.

    PubMed

    Pellegrini, Manuel J; Adams, Samuel B; Parekh, Selene G

    2014-06-24

    Chronic peroneal tendinopathy and tears represent a challenging clinical situation. Traditionally, tenodesis of the torn tendon to the remaining healthy tendon has been advocated if more than half of the tendon is compromised. Allograft reconstructions have been reserved for patients with functional muscles and both peroneal tendons extensively compromised. We report a unique case of a peroneal tenodesis takedown and reconstruction of both peroneal tendons using semitendinosus allograft. A description of the surgical technique and tips are provided. Peroneal tendon function is crucial to maintain a balanced hindfoot. To the best of our knowledge, reconstruction of both peroneal tendons after a tenodesis has not been previously reported. Allograft reconstruction of the peroneal tendons arises as a feasible alternative in patients with residual pain and weakness after a failed tenodesis surgery LEVELS OF EVIDENCE: Therapeutic Level IV, case study. PMID:24962697

  14. Unstable elbow dislocations: the description and cadaveric feasibility study of a new surgical technique

    PubMed Central

    Harris, Mark; Bishop, Timothy; Bernard, Jason

    2015-01-01

    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. PMID:27163079

  15. A Simple Technique for Surgical Placement of Occipital Nerve Stimulators without Anchoring the Lead.

    PubMed

    Plazier, Mark; Camp, Tim Van; Mevnosky, Tomas; Ost, Jan; De Ridder, Dirk; Vanneste, Sven

    2016-09-01

    Introduction Greater occipital nerve stimulation is applied in the treatment of occipital neuralgia, headache, and fibromyalgia. Multiple techniques have been described along with their subsequent complications. The most frequent complications are related to lead migration, infection, and undesired stimulation effects. Revision surgery occurs in up to 60% of the cases. Patients and Methods A total of 92 implantations, 51 trials (6-10 weeks), and 41 permanent implantations (follow-up: 36-72 months) were performed in a single center using a simple technique without an anchoring device. The electrode is tunneled at a 45-degree angle to prevent migration. Complications and additional surgeries were recorded during the follow-up period. Results All patients had bilateral greater occipital nerve stimulation. A total of 16 complications (17.4%) occurred. Seven patients (7.6%) underwent additional surgery. The major complication was infection; lead migration made up only 3.3% of the complications. Conclusions We present a simple technique without the use of an anchoring device that is feasible in achieving bilateral occipital nerve stimulation and decreases the complications, especially lead migration. PMID:26444964

  16. Vascular Surgery Trainees Still Need to Learn How to Sew: Importance of Learning Surgical Techniques in the Era of Endovascular Surgery

    PubMed Central

    Aziz, Faisal

    2015-01-01

    Vascular surgery represents one of the most rapidly evolving specialties in the field of surgery. It was merely 100 years ago when Dr. Alexis Carrel described vascular anastomosis. Over the course of next several decades, vascular surgeons distinguished themselves from general surgeons by horning the techniques of vascular surgery operations. In the era of minimally invasive interventions, the number of endovascular interventions performed by vascular surgeons has increased exponentially. Vascular surgery trainees in the current times spend considerable time in mastering the techniques of endovascular operations. Unfortunately, the reduction in number of open surgical operations has lead to concerns in regards to adequacy of learning open surgical techniques. In future, majority of vascular interventions will be done with minimally invasive techniques. Combination of poor training in open operations and increasing complexity of open surgical operations may lead to poor surgical outcomes. It is the need of the hour for vascular surgery trainees to realize the importance of learning and mastering open surgical techniques. One of the most distinguishing features of contemporary vascular surgeons is their ability to perform both endovascular and open vascular surgery operations, and we should strive to maintain our excellence in both of these arenas. PMID:26029698

  17. Vascular surgery trainees still need to learn how to sew: importance of learning surgical techniques in the era of endovascular surgery.

    PubMed

    Aziz, Faisal

    2015-01-01

    Vascular surgery represents one of the most rapidly evolving specialties in the field of surgery. It was merely 100 years ago when Dr. Alexis Carrel described vascular anastomosis. Over the course of next several decades, vascular surgeons distinguished themselves from general surgeons by horning the techniques of vascular surgery operations. In the era of minimally invasive interventions, the number of endovascular interventions performed by vascular surgeons has increased exponentially. Vascular surgery trainees in the current times spend considerable time in mastering the techniques of endovascular operations. Unfortunately, the reduction in number of open surgical operations has lead to concerns in regards to adequacy of learning open surgical techniques. In future, majority of vascular interventions will be done with minimally invasive techniques. Combination of poor training in open operations and increasing complexity of open surgical operations may lead to poor surgical outcomes. It is the need of the hour for vascular surgery trainees to realize the importance of learning and mastering open surgical techniques. One of the most distinguishing features of contemporary vascular surgeons is their ability to perform both endovascular and open vascular surgery operations, and we should strive to maintain our excellence in both of these arenas. PMID:26029698

  18. Optimization techniques in molecular structure and function elucidation.

    PubMed

    Sahinidis, Nikolaos V

    2009-12-01

    This paper discusses recent optimization approaches to the protein side-chain prediction problem, protein structural alignment, and molecular structure determination from X-ray diffraction measurements. The machinery employed to solve these problems has included algorithms from linear programming, dynamic programming, combinatorial optimization, and mixed-integer nonlinear programming. Many of these problems are purely continuous in nature. Yet, to this date, they have been approached mostly via combinatorial optimization algorithms that are applied to discrete approximations. The main purpose of the paper is to offer an introduction and motivate further systems approaches to these problems. PMID:20160866

  19. Improving Double Docking for Robot-assisted Para-aortic Lymphadenectomy in Endometrial Cancer Staging: Technique and Surgical Outcomes.

    PubMed

    Ekdahl, Linnea; Salehi, Sahar; Falconer, Henrik

    2016-01-01

    Robot-assisted para-aortic lymphadenectomy (PALND) may prove to be a challenging procedure, and the ability to reach the planned anatomic landmarks is critical. In this retrospective study between 2012 and 2015, we present surgical data using a modified technique to perform infrarenal PALND for endometrial cancer using double side docking. All women with high-risk endometrial cancer scheduled for complete robotic staging including infrarenal PALND were included in the analysis. During the study period, a total of 76 women were identified. Three patients had disseminated disease and were treated with palliative hysterectomy only. The remaining 73 women underwent surgery with the intention to perform infrarenal PALND. In 7 cases, PALND was aborted because of technical inability to reach the left renal vein (10%). A median of 36 lymph nodes were harvested (pelvic n = 20, para-aortic n = 16). The median operating time (skin to skin) for patients with completed infrarenal PALND was 228 minutes (range, 181-371 minutes). Among all 76 patients, postoperative complications according to the Clavien-Dindo nomenclature were observed in 27 (36%) patients, with 6 (8%) having grade III complications. No patient died within 30 days from surgery. Our technique of double docking for robot-assisted PALND was associated with a success rate of 90%. The described technique seems to be a useful strategy to maximize the likelihood of completing the planned procedure. PMID:27063093

  20. Dynamic medial patellofemoral ligament reconstruction in recurrent patellar instability: A surgical technique

    PubMed Central

    Kiran, Kopuri Ravi; Srikanth, I Muni; Chinnusamy, Lenin; Deepti, K

    2015-01-01

    The medial patellofemoral ligament (MPFL) is the primary stabilizer of the patellofemoral joint; its reconstruction has been recommended in adults over the past decade after recurrent patellar instability. However, there has been no standardized technique for reconstruction, therefore, ideal graft and technique for reconstruction are yet undetermined. However, dynamic MPFL reconstruction studies claim to be superior to other procedures as it is more anatomical. This preliminary study aims at assessing the outcomes of MPFL reconstruction in a dynamic pattern using hamstring graft. We performed this procedure in four consecutive patients with chronic patellar instability following trauma. MPFL reconstruction was done with hamstring tendons detached distally and secured to patellar periosteum after being passed through a bony tunnel in the patella without an implant and using the medial collateral ligament as a pulley. In all 4 knees, the MPFL reconstruction was isolated and was not associated with any other realignment procedures. No recurrent episodes of dislocation or subluxation were reported at 24 months followup. PMID:26806970

  1. Urolift: a New Face of Minimally Invasive Surgical Technique for Benign Prostatic Hyperplasia?

    PubMed

    Tsui, Johnson F; Dixon, Christopher M

    2016-09-01

    The management of clinical benign prostatic hyperplasia (BPH) remains a common problem in daily urologic practice. Recently, a new minimally invasive procedure for BPH, the Urolift System, has been introduced. This article reviews the current literature discussing the technique, efficacy, adverse events, limitations, and possible concerns. The existing data which includes a 3-month, sham-controlled multicenter trial with a subsequent 3-year follow-up indicates significant improvements in the outcome measures in particular urinary symptoms. The adverse event profile and reoperation rates are acceptable. A particular benefit includes the lack of negative effects on erectile or ejaculatory function. The procedure can be performed with minimal anesthesia, but is limited to lateral lobe enlargement as it is unsuitable for median lobe or central zone obstruction. Another potential drawback is the placement of permanent implants into the prostatic urethra. The adoption of this procedure will ultimately be determined by multiple factors including ease of use, patient satisfaction, durability, and reimbursement. PMID:27432380

  2. Testicular Interposition Flap for Repair of Perineal Urinary Fistulae: A Novel Surgical Technique

    PubMed Central

    Raup, Valary T.; Eswara, Jairam R.; Marshall, Stephen D.; Brandes, Steven B.

    2015-01-01

    Rectourinary fistulae and urinary-cutaneous fistulae are a rare yet devastating complication. Current options for tissue interposition include rectus, gracilis, or gluteal muscle, omentum, or intestine for use in coloanal pull-through procedures. In elderly patients, testicular interposition flaps may be an excellent tissue option to use when vitalized tissue is necessary to supplement fistula repair. Elderly patients frequently have increased spermatic cord length, potentially offering a longer flap reach than use of a muscle flap. Additionally, mobilizing one of the testicles and developing it through the external inguinal ring may be a less morbid and less costly procedure than harvesting and tunneling a muscle flap. Longer follow-up and further studies are needed to determine the outcomes of this novel technique. PMID:26483985

  3. Osteochondral Autograft Transplantation: A Review of the Surgical Technique and Outcomes.

    PubMed

    Richter, Dustin L; Tanksley, John A; Miller, Mark D

    2016-06-01

    Isolated chondral and osteochondral defects of the knee are challenging clinical entities, particularly in younger patients. Cartilage treatment strategies have previously been characterized as palliation (ie, chondroplasty and debridement), repair (ie, drilling and microfracture), or restoration (ie, autologous chondrocyte implantation, osteochondral autograft, and osteochondral allograft). The osteochondral autograft transplantation procedure allows defects to be filled immediately with mature, hyaline articular cartilage by utilizing either an arthroscopic or a mini-open procedure. Graft harvest and placement can be technically demanding, but results show trends toward greater longevity, durability, and improved outcomes in high-demand patients when compared with alternative techniques. Improved results are shown in younger patients with isolated lesions between 1 and 4 cm. PMID:27135290

  4. Principles and techniques used to create a natural hairline in surgical hair restoration.

    PubMed

    Shapiro, Ronald

    2004-05-01

    The principles and techniques outlined in this article will help the surgeon create hairlines that have the high degree of naturalness and substance expected by today's discerning patients. Surgeons can now establish a natural hairline during the first surgery that can stand on its own, independent of further sessions. It is not enough to "just use micrografts."Proper selection and use of FUs combined with artistry and skill provide surgeons with the tools to follow nature's lead in creating natural-appearing,soft hairlines while establishing the illusion of density. The author's approach is to create an initial framework based on the principles of hairline design,then use artistic ability and experience to fine-tune this framework. PMID:15135130

  5. Robot-Assisted Extended Pelvic Lymph Nodes Dissection for Prostate Cancer: Personal Surgical Technique and Outcomes

    PubMed Central

    Francesco, Porpiglia; Stefano, De Luca; Riccardo, Bertolo; Roberto, Passera; Fabrizio, Mele; Matteo, Manfredi; Daniele, Amparore; Ivano, Morra; Cristian, Fiori

    2015-01-01

    ABSTRACT Objective: Extended pelvic lymph nodes dissection (EPLND) allows the removal of a higher number of lymph nodes than limited PLND. The aims of this study were to describe our robot-assisted EPLND (RAEPLND) technique with related complications, and to report the number of lymph nodes removed and the rate of lymph nodal metastasis. Materials and Methods: 153 patients underwent RAEPLND prior to robot-assisted radical prostatectomy (RARP). Indications were defined according to Briganti nomogram, to predict risk of lymph-nodal metastasis. Lymphatic packages covering the distal tract of the common iliac artery, the medial portion of the external iliac artery, the external iliac vein and the internal iliac vessels, together with the obturator and the presacral lymphatic packages were removed on both sides. Results: Median preoperative PSA was 7.5 ng/mL (IQR 5.5–11.5). Median operative time was 150 min (135–170). Median RAEPLND alone operative time was 38 min (32.75–41.25); for right and left side, 18 (15–29) and 20 min (15.75–30) (p=0.567). Median number of lymph nodes retrieved per patient was 25 (19.25–30); 13 (11–16) and 11 (8–15) for right and left side. In 19 patients (12.41%) metastasis was found at the level of pelvic lymph nodes. Median number of positive lymph nodes was 1 (1–4.6) per patient. Complications occurred in 11 patients (7.3%). Conclusions: the number of lymph nodes removed was comparable to published data about open series, allowing the increase of detection rate of lymph nodal metastasis for minimally invasive approach without compromising complications' rate if performing the procedure following reported technique. PMID:26742982

  6. Cochlear implantation through the round window with a straight slotted electrode array: optimizing the surgical procedure.

    PubMed

    Mom, Thierry; Bachy, Aurélie; Houette, Aubry; Pavier, Yoann; Pastourel, Rémy; Gabrillargues, Jean; Saroul, Nicolas; Gilain, Laurent; Avan, Paul

    2016-04-01

    The question addressed here is how optimizing the quality of insertion through the round window with the lower morbidity, when using a straight and slotted electrode array of regular length. This retrospective analysis includes all cases implanted with a cochlear implant Digisonic SP (Neurelec-Oticon Medical) since 2004. We checked the operative charts, the depth of insertion, and the follow-up. For comparisons, contingency tables were used and a Chi-square test was performed. A p value <0.05 was considered significant. 126 cases of patients with non-malformed cochleas were implanted through the round window. The mean age was 53.8 ± 16.2 for adults and 3.6 ± 2.6 for children (24 cases). The mean follow-up was 33 ± 22 months. The straight electrode array had either a square or a soft pointed tip (n = 84). Full insertion was achieved in 79 out of 84 cases with a soft tip vs. 18 out of 42 square tips (χ (2) = 41.41, DOF = 1, p < 0.0001). Two cases were stuck at the round window niche by a prominent crista fenestrae. In all cases but one, the chorda tympany was preserved. In one case, a misrouting to the vestibule required a revision surgery. Implantation through the round window with a straight and slotted electrode array with a soft tip (Digisonic SP, Neurelec-Oticon Medical) can lead to a full insertion in 94 % of cases. Drilling out a prominent crista fenestrae is recommended. PMID:25894503

  7. Reconstruction of the mandible and the maxilla: the evolution of surgical technique.

    PubMed

    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. PMID:20231587

  8. Comparison of 3 different anesthetic techniques on 24-hour recovery after otologic surgical procedures.

    PubMed

    Jellish, W S; Leonetti, J P; Fahey, K; Fury, P

    1999-03-01

    Intravenous propofol anesthesia is better than inhalational anesthesia for otologic surgery, but cost and intraoperative movement make this technique prohibitive. This study compares a propofol sandwich anesthetic with a total propofol or inhalational anesthetic for otologic surgery to determine which produces the best perioperative conditions and least expense. One hundred twenty patients undergoing ear surgery were randomly chosen to receive an anesthetic with either isoflurane (INHAL), total propofol (TPROP), or propofol used in conjunction with isoflurane (PSAND). Postoperative wakeup and the incidence and severity of nausea, vomiting, and pain were compared among groups. Antiemetic administration and discharge times from recovery and the hospital were also compared. The groups were similar, but anesthesia times were longer in the INHAL group. Emergence from anesthesia after PSAND or TPROP was more rapid than after INHAL. Recovery during the next 24 hours was associated with less nausea and vomiting with PSAND than with INHAL. The cost of the PSAND anesthetic was similar to that of INHAL, and both were less than TPROP. PSAND anesthesia may be similar to TPROP and better than INHAL for otologic procedures. PSAND was less expensive than TPROP and produced a similar recovery profile and antiemetic effect in the 24-hour period after surgery. PMID:10064647

  9. Dependency between treatment outcome in pseudarthrosis of the humeral shaft and the surgical technique applied.

    PubMed

    Piotrowski, Maciej; Baczkowski, Bogusław; Markowicz, Agnieszka; Pankowski, Rafał; Luczkiewicz, Piotr

    2005-08-30

    Background. Treatment of non-union has always been one of the most difficult problems in bone pathology. In the present study we compare outcomes using 9 different methods of non-union treatment. Material and methods. From 1976 to 2003, 70 patients with 85 cases of pseudoarthrosis in the humeral shaft were operated. During that period, 103 operations using 9 different methods were performed. The study group consisted of 17 females, 36 males and 17 children, ranging in age from 3 to 85 years. The operation techniques were compared based on the achievement of bone union and recovery of limb functional efficiency. Nonunion type was also taken into account. Results. A high percentage of bone union was obtained by using a perforated block of corticocancellous graft taken from the iliac crest. The most complete limb function recovery was achieved using this method, as well as Judet's decortication with cancellous grafting and firm osteosynthesis. Conclusions. In oligotrophic and non-viable humeral shaft non-union, the most effective method is pseudarthrosis excision, using a perforated block of corticocancellous graft from the iliac crest to fill the gap, and firm osteosynthesis. Judet's decortication with cancellous grafting and firm osteosynthesis secured good outcome in hypertrophic pseudarthrosis. PMID:17611455

  10. Novel Techniques with the Aid of a Staged CBCT Guided Surgical Protocol

    PubMed Central

    Drew, Howard

    2015-01-01

    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. PMID:25632356

  11. Novel Techniques with the Aid of a Staged CBCT Guided Surgical Protocol.

    PubMed

    Chasioti, Evdokia; Sayed, Mohammed; Drew, Howard

    2015-01-01

    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. PMID:25632356

  12. Optimization techniques applied to passive measures for in-orbit spacecraft survivability

    NASA Technical Reports Server (NTRS)

    Mog, Robert A.; Price, D. Marvin

    1987-01-01

    Optimization techniques applied to passive measures for in-orbit spacecraft survivability, is a six-month study, designed to evaluate the effectiveness of the geometric programming (GP) optimization technique in determining the optimal design of a meteoroid and space debris protection system for the Space Station Core Module configuration. Geometric Programming was found to be superior to other methods in that it provided maximum protection from impact problems at the lowest weight and cost.

  13. Adjoint Techniques for Topology Optimization of Structures Under Damage Conditions

    NASA Technical Reports Server (NTRS)

    Akgun, Mehmet A.; Haftka, Raphael T.

    2000-01-01

    The objective of this cooperative agreement was to seek computationally efficient ways to optimize aerospace structures subject to damage tolerance criteria. Optimization was to involve sizing as well as topology optimization. The work was done in collaboration with Steve Scotti, Chauncey Wu and Joanne Walsh at the NASA Langley Research Center. Computation of constraint sensitivity is normally the most time-consuming step of an optimization procedure. The cooperative work first focused on this issue and implemented the adjoint method of sensitivity computation (Haftka and Gurdal, 1992) in an optimization code (runstream) written in Engineering Analysis Language (EAL). The method was implemented both for bar and plate elements including buckling sensitivity for the latter. Lumping of constraints was investigated as a means to reduce the computational cost. Adjoint sensitivity computation was developed and implemented for lumped stress and buckling constraints. Cost of the direct method and the adjoint method was compared for various structures with and without lumping. The results were reported in two papers (Akgun et al., 1998a and 1999). It is desirable to optimize topology of an aerospace structure subject to a large number of damage scenarios so that a damage tolerant structure is obtained. Including damage scenarios in the design procedure is critical in order to avoid large mass penalties at later stages (Haftka et al., 1983). A common method for topology optimization is that of compliance minimization (Bendsoe, 1995) which has not been used for damage tolerant design. In the present work, topology optimization is treated as a conventional problem aiming to minimize the weight subject to stress constraints. Multiple damage configurations (scenarios) are considered. Each configuration has its own structural stiffness matrix and, normally, requires factoring of the matrix and solution of the system of equations. Damage that is expected to be tolerated is local

  14. Design of high speed proprotors using multiobjective optimization techniques

    NASA Technical Reports Server (NTRS)

    Mccarthy, Thomas R.; Chattopadhyay, Aditi

    1992-01-01

    An integrated, multiobjective optimization procedure is developed for the design of high speed proprotors with the coupling of aerodynamic, dynamic, aeroelastic, and structural criteria. The objectives are to maximize propulsive efficiency in high speed cruise and rotor figure of merit in hover. Constraints are imposed on rotor blade aeroelastic stability in cruise and on total blade weight. Two different multiobjective formulation procedures, the Min summation of beta and the K-S function approaches are used to formulate the two-objective optimization problems.

  15. Optimizing Basic French Skills Utilizing Multiple Teaching Techniques.

    ERIC Educational Resources Information Center

    Skala, Carol

    This action research project examined the impact of foreign language teaching techniques on the language acquisition and retention of 19 secondary level French I students, focusing on student perceptions of the effectiveness and ease of four teaching techniques: total physical response, total physical response storytelling, literature approach,…

  16. Long-term results of the surgical treatment of Peyronie's disease with Egydio's technique: a European multicentre study

    PubMed Central

    Sansalone, Salvatore; Garaffa, Giulio; Djinovic, Rados; Pecoraro, Stefano; Silvani, Mauro; Barbagli, Guido; Zucchi, Alessandro; Vespasiani, Giuseppe; Loreto, Carla

    2011-01-01

    The long-term outcomes of 157 patients affected by Peyronie's disease (PD) who underwent penile straightening with Egydio's technique between January 2004 and December 2008 are reported. Only patients with PD who were stable for at least 6–12 months prior to surgery were enrolled in this study. Preoperative assessment included a dynamic echo colour Doppler ultrasound scan to evaluate the degree of penile deformity and the peak systolic velocity in the cavernosal arteries and an assessment of erectile function with the administration of the International Index of Erectile Function 5 (IIEF-5) questionnaire. Stretched penile length was recorded pre- and postoperatively. Surgical complications, cosmesis and sexual function, patient satisfaction and postoperative erectile function were assessed postoperatively at 3 months, 1 year and 2 years, respectively. After a median follow-up period of 20 months (range: 12–24 months), we found that mild residual curvature (12%) and glans hypoesthesia (3%) were the only causes of partial dissatisfaction. No rejection of the graft was observed. All patients recovered their ability to penetrate with no difficulty. In addition, an intraoperative average increase of 2.5 cm (range: 1.7–4.1 cm) in stretched penile length was recorded, with all patients engaging in penetrative sexual intercourse. In conclusion, this procedure represents a safe and reproducible technique for the correction of penile curvature resulting from PD and yields excellent cosmetic and functional results. PMID:21743482

  17. The Use of MMF Screws: Surgical Technique, Indications, Contraindications, and Common Problems in Review of the Literature

    PubMed Central

    Cornelius, Carl-Peter; Ehrenfeld, Michael

    2010-01-01

    Mandibulo-maxillary fixation (MMF) screws are inserted into the bony base of both jaws in the process of fracture realignment and immobilisation. The screw heads act as anchor points to fasten wire loops or rubber bands connecting the mandible to the maxilla. Traditional interdental chain-linked wiring or arch bar techniques provide the anchorage by attached cleats, hooks, or eyelets. In comparison to these tooth-borne appliances MMF screws facilitate and shorten the way to achieve intermaxillary fixation considerably. In addition, MMF screws help to reduce the hazards of glove perforation and wire stick injuries. On the downside, MMF screws are attributed with the risk of tooth root damage and a lack of versatility beyond the pure maintenance of occlusion such as stabilizing loose teeth or splinting fragments of the alveolar process. The surgical technique of MMF screws as well as the pros and cons of the clinical application are reviewed. The adequate screw placement to prevent serious tooth root injuries is still an issue to rethink and modify conceptual guidelines. PMID:22110819

  18. Clinical Outcome of a Wide-diameter Bone-anchored Hearing Implant and a Surgical Technique With Tissue Preservation

    PubMed Central

    Mowinckel, Marius S.; Møller, Martin N.; Wielandt, Kirsten N.; Foghsgaard, Søren

    2016-01-01

    Objective: To investigate the clinical outcome of a surgical technique with tissue preservation for a wide bone-anchored hearing implant concerning postoperative complications, skin reactions, implant loss, and implant stability. Study Design: Consecutive, prospective case series. Setting: Tertiary referral center. Patients: Twenty-four adult patients with normal skin quality were enrolled. Intervention(s): Implantation of bone-anchored implant was performed using a one-stage linear-incision technique with tissue preservation surgery. Main Outcome Measures(s): Skin and soft tissue reactions according to Holgers grading system. Pain and numbness measured according to visual analogue scale. Implant stability quotient values were recorded using resonance frequency analysis. Follow-up at 10 days, 6 weeks, 6 months, and 1 year after surgery. Results: Primary implant stability was good and a significant increase in implant stability quotient occurred during the first 10 days and continued to be stable throughout the 1-year observation period. No implants were lost. Skin and soft tissue reactions were few, no reaction (Holger grade 0) was observed in 88% of the follow-up examinations and no grade 4 reactions occurred. Pain and numbness were minimal. Conclusion: The wide implant showed good stability initially and throughout the observation period. Skin and soft tissue reactions were rare and minor. No implants were lost. PMID:26954348

  19. Surgical management of fecal incontinence.

    PubMed

    Bleier, Joshua I S; Kann, Brian R

    2013-12-01

    The surgical approach to treating fecal incontinence is complex. After optimal medical management has failed, surgery remains the best option for restoring function. Patient factors, such as prior surgery, anatomic derangements, and degree of incontinence, help inform the astute surgeon regarding the most appropriate option. Many varied approaches to surgical management are available, ranging from more conservative approaches, such as anal canal bulking agents and neuromodulation, to more aggressive approaches, including sphincter repair, anal cerclage techniques, and muscle transposition. Efficacy and morbidity of these approaches also range widely, and this article presents the data and operative considerations for these approaches. PMID:24280402

  20. Surgical management of ectopic pregnancy.

    PubMed

    Stock, Laura; Milad, Magdy

    2012-06-01

    Surgery remains an acceptable, and sometimes necessary, modality for the treatment of ectopic pregnancy. Laparoscopy is the preferred method of access, yet controversy remains regarding the optimal procedure and postoperative management. Generally, salpingostomy is employed with the goal of maintaining fertility, although data to support this tenet are lacking. In most cases, the decision to perform conservative versus radical surgery is on the basis of the patient's history, her desire for future fertility, and surgical findings. The procedures of salpingostomy and salpingectomy, techniques to prevent and control blood loss at the time of surgery, and surgical options for nontubal ectopic pregnancies are reviewed. PMID:22510627

  1. Basal Cell Carcinoma of the Outer Nose: Overview on Surgical Techniques and Analysis of 312 Patients

    PubMed Central

    Wollina, Uwe; Bennewitz, Annett; Langner, Dana

    2014-01-01

    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. PMID:25538434

  2. Iliac crest allograft glenoid reconstruction for recurrent anterior shoulder instability in athletes: Surgical technique and results

    PubMed Central

    Mascarenhas, Randy; Raleigh, Eden; McRae, Sheila; Leiter, Jeff; Saltzman, Bryan; MacDonald, Peter B.

    2014-01-01

    Performing a labral repair alone in patients with recurrent anterior instability and a large glenoid defect has led to poor outcomes. We present a technique involving the use of the iliac crest allograft inserted into the glenoid defect in athletes with recurrent anterior shoulder instability and large bony defects of the glenoid (>25% of glenoid diameter). All athletes with recurrent anterior shoulder instability and a large glenoid defect that underwent open anterior shoulder stabilization and glenoid reconstruction with the iliac crest allograft were followed over a 4-year period. Preoperatively, a detailed history and physical exam were obtained along with standard radiographs and magnetic resonance imaging of the affected shoulder. All patients also completed the Simple Shoulder Test (SST) and American Shoulder and Elbow Surgeons (ASES) evaluation forms preoperatively. A computed tomography scan was obtained postoperatively to assess osseous union of the graft and the patient again went through a physical exam in addition to completing the SST, ASES, and Western Ontario Shoulder Instability Index (WOSI) forms. 10 patients (9 males, 1 female) were followed for an average of 16 months (4–36 months) and had a mean age of 24.4 years. All patients exhibited a negative apprehension/relocation test and full shoulder strength at final follow-up. Eight of 10 patients had achieved osseous union at 6 months (80.0%). ASES scores improved from 64.3 to 97.8, and SST scores improved from 66.7 to 100. Average postoperative WOSI scores were 93.8%. The use of the iliac crest allograft provides a safe and clinically useful alternative compared to previously described procedures for recurrent shoulder instability in the face of glenoid deficiency. PMID:25538432

  3. Early surgical and functional outcomes comparison of the supercapsular percutaneously-assisted total hip and traditional posterior surgical techniques for total hip arthroplasty: protocol for a randomized, controlled study

    PubMed Central

    Cronin, Michael D.; Gofton, Wade; Erwin, Lindsey; Chow, James

    2015-01-01

    Background Total hip arthroplasty (THA) is one of the most commonly performed and successful orthopaedic surgeries. While the long-term success of THA is well documented, there is still significant room for improving patient speed of recovery and return to activities. The surgical technique used during THA has the potential to affect these early outcomes. Methods The described design is a single center, prospective, randomized, controlled study. Subjects will be randomized to receive THA using either the supercapsular percutaneously-assisted total hip (SuperPath) or traditional posterior surgical techniques. Subjects will be evaluated using Timed Up and Go (TUG), Timed Stair Climb (TSC), Hip Dysfunction and Osteoarthritis Outcome Score (HOOS), and Visual Analog Scale (VAS) for pain level estimation preoperatively, during the hospital stay, and at 2, 6 weeks, and 100 days post-discharge. Other endpoints to be evaluated include: length of stay (LOS); discharge status; transfusion rates; readmission rates; complication rates; operative time; date returned to work; and acetabular component anteversion and inclination angles. Discussion The described study will determine the effect of a tissue-sparing surgical technique on short term subject recovery following THA in comparison to the most commonly used technique in clinical practice. PMID:26734645

  4. Prospective Study of the Surgical Techniques Used in Primary Rhinoplasty on the Caucasian Nose and Comparison of the Preoperative and Postoperative Anthropometric Nose Measurements

    PubMed Central

    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

  5. Comparison of Surgical Blade and Cryosurgery with Liquid Nitrogen Techniques in Treatment of Physiologic Gingival Pigmentation: Short Term Results

    PubMed Central

    Rahmati, Saeed; Darijani, Mansoore; Nourelahi, Maryam

    2014-01-01

    Statement of the Problem: Melanin pigmentation of the gingiva is a crucial esthetic problem. A variety of methods have been used for gingival depigmentation. Purpose: The purpose of this study was to compare the results of two treatment modalities: scalpel technique and cryotherapy with liquid nitrogen in treatment of gingival pigmentation. Materials and Method: Twenty patients with chief complaint of gingival pigmentation participated in our study. 10 patients were treated with cryotherapy and remaining 10 participants were undergone the scalpel technique surgery. We evaluated acquiescence and comfort of the patients, degree of depigmentation, based on the area of pigmentation shown by gridlines option in Microsoft Paint software, and the presence or absence of gingival recession before and one month after treatment. Data was analyzed using Mann-Whitney and Chi-Square tests. A significance level of p≤ 0.05 was adopted. Results: Mean value and standard deviation of depigmentation for group A and group B was 96.17±2.51 and 95±2.48, respectively. The difference was not statistically significant (p= 0.225). There was no association between the treatment modality and the gingival recession (p= 0.303) or the treatment modality and the patient satisfaction (p= 0.346). No significant difference was found between gingival recession measures before and after the operation in the two treatment modalities. Conclusion: Surgical blade and cryosurgery with liquid nitrogen had no significant difference in treatment of physiologic gingival pigmentation. Both Techniques are acceptable in the treatment of gingival pigmentation. PMID:25469354

  6. Clinical results of a surgical technique using endobuttons for complete tendon tear of pectoralis major muscle: report of five cases

    PubMed Central

    2011-01-01

    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. PMID:21955511

  7. Optimal feedback control infinite dimensional parabolic evolution systems: Approximation techniques

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Wang, C.

    1989-01-01

    A general approximation framework is discussed for computation of optimal feedback controls in linear quadratic regular problems for nonautonomous parabolic distributed parameter systems. This is done in the context of a theoretical framework using general evolution systems in infinite dimensional Hilbert spaces. Conditions are discussed for preservation under approximation of stabilizability and detectability hypotheses on the infinite dimensional system. The special case of periodic systems is also treated.

  8. Asynchronous global optimization techniques for medium and large inversion problems

    SciTech Connect

    Pereyra, V.; Koshy, M.; Meza, J.C.

    1995-04-01

    We discuss global optimization procedures adequate for seismic inversion problems. We explain how to save function evaluations (which may involve large scale ray tracing or other expensive operations) by creating a data base of information on what parts of parameter space have already been inspected. It is also shown how a correct parallel implementation using PVM speeds up the process almost linearly with respect to the number of processors, provided that the function evaluations are expensive enough to offset the communication overhead.

  9. Optimization techniques for OpenCL-based linear algebra routines

    NASA Astrophysics Data System (ADS)

    Kozacik, Stephen; Fox, Paul; Humphrey, John; Kuller, Aryeh; Kelmelis, Eric; Prather, Dennis W.

    2014-06-01

    The OpenCL standard for general-purpose parallel programming allows a developer to target highly parallel computations towards graphics processing units (GPUs), CPUs, co-processing devices, and field programmable gate arrays (FPGAs). The computationally intense domains of linear algebra and image processing have shown significant speedups when implemented in the OpenCL environment. A major benefit of OpenCL is that a routine written for one device can be run across many different devices and architectures; however, a kernel optimized for one device may not exhibit high performance when executed on a different device. For this reason kernels must typically be hand-optimized for every target device family. Due to the large number of parameters that can affect performance, hand tuning for every possible device is impractical and often produces suboptimal results. For this work, we focused on optimizing the general matrix multiplication routine. General matrix multiplication is used as a building block for many linear algebra routines and often comprises a large portion of the run-time. Prior work has shown this routine to be a good candidate for high-performance implementation in OpenCL. We selected several candidate algorithms from the literature that are suitable for parameterization. We then developed parameterized kernels implementing these algorithms using only portable OpenCL features. Our implementation queries device information supplied by the OpenCL runtime and utilizes this as well as user input to generate a search space that satisfies device and algorithmic constraints. Preliminary results from our work confirm that optimizations are not portable from one device to the next, and show the benefits of automatic tuning. Using a standard set of tuning parameters seen in the literature for the NVIDIA Fermi architecture achieves a performance of 1.6 TFLOPS on an AMD 7970 device, while automatically tuning achieves a peak of 2.7 TFLOPS

  10. An Optimal Cell Detection Technique for Automated Patch Clamping

    NASA Technical Reports Server (NTRS)

    McDowell, Mark; Gray, Elizabeth

    2004-01-01

    While there are several hardware techniques for the automated patch clamping of cells that describe the equipment apparatus used for patch clamping, very few explain the science behind the actual technique of locating the ideal cell for a patch clamping procedure. We present a machine vision approach to patch clamping cell selection by developing an intelligent algorithm technique that gives the user the ability to determine the good cell to patch clamp in an image within one second. This technique will aid the user in determining the best candidates for patch clamping and will ultimately save time, increase efficiency and reduce cost. The ultimate goal is to combine intelligent processing with instrumentation and controls in order to produce a complete turnkey automated patch clamping system capable of accurately and reliably patch clamping cells with a minimum amount of human intervention. We present a unique technique that identifies good patch clamping cell candidates based on feature metrics of a cell's (x, y) position, major axis length, minor axis length, area, elongation, roundness, smoothness, angle of orientation, thinness and whether or not the cell is only particularly in the field of view. A patent is pending for this research.

  11. Comparison of two cochlear implantation techniques and their effects on the preservation of residual hearing. Is the surgical approach of any importance?

    PubMed

    Postelmans, J T F; Stokroos, R J; van Spronsen, E; Grolman, W; Tange, R A; Maré, M J; Dreschler, Wouter Albert

    2014-05-01

    The goal of this work was to review the pre-and postsurgical auditory thresholds of two surgical implantation techniques, namely the mastoidectomy with posterior tympanotomy approach (MPTA) and suprameatal approach (SMA), to determine whether there is a difference in the degree of preservation of residual hearing. In a series of 430 consecutive implanted patients 227 patients had measurable pre-operative hearing thresholds at 250, 500, and 1,000 Hz. These patients were divided into two groups according to the surgical technique that was used for implantation. The SMA approach was followed for 84 patients in Amsterdam, whereas the MPTA technique was adhered to 143 patients in Maastricht. The outcome variables of interest were alteration of pre-and postoperative auditory thresholds after cochlear implantation. Complete or partial preservation of residual hearing was obtained in 21.4 and 21.7% in the SMA and MPTA group, respectively. No statistical differences could be found between the SMA and MPTA group (p = 0.96; Chi-square test). The SMA technique is correlated with a similar degree of hearing loss after cochlear implantation compared to the MPTA technique. However, both techniques were not able to conserve a measurable amount of hearing in patients with a substantial degree of residual hearing. Therefore, both surgical techniques need to be refined for patients in which residual acoustical hearing is pursued. PMID:23632865

  12. Space shuttle propulsion parameter estimation using optimal estimation techniques

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The first twelve system state variables are presented with the necessary mathematical developments for incorporating them into the filter/smoother algorithm. Other state variables, i.e., aerodynamic coefficients can be easily incorporated into the estimation algorithm, representing uncertain parameters, but for initial checkout purposes are treated as known quantities. An approach for incorporating the NASA propulsion predictive model results into the optimal estimation algorithm was identified. This approach utilizes numerical derivatives and nominal predictions within the algorithm with global iterations of the algorithm. The iterative process is terminated when the quality of the estimates provided no longer significantly improves.

  13. Application of optimal data assimilation techniques in oceanography

    SciTech Connect

    Miller, R.N.

    1996-12-31

    Application of optimal data assimilation methods in oceanography is, if anything, more important than it is in numerical weather prediction, due to the sparsity of data. Here, a general framework is presented and practical examples taken from the author`s work are described, with the purpose of conveying to the reader some idea of the state of the art of data assimilation in oceanography. While no attempt is made to be exhaustive, references to other lines of research are included. Major challenges to the community include design of statistical error models and handling of strong nonlinearity.

  14. PRE-OPERATIVE PLANNING AND SURGICAL TECHNIQUE OF THE OPEN WEDGE SUPRACONDYLAR OSTEOTOMY FOR CORRECTION OF VALGUS KNEE AND FIXATION WITH A FIXED-ANGLE IMPLANT

    PubMed Central

    Paccola, Cleber Antonio Jansen

    2015-01-01

    The step-by-step preoperative planning for supracondylar opening wedge osteotomy of the femur for precise correction of the load axis of the lower limb using a fixed-angle implant (95° AO blade plate) is presented. The surgical technique and the use of a bone graft from the same site for filling in the defect are also presented. PMID:27026976

  15. Intermediate-Term Outcomes of Dual Adult versus Single-Kidney Transplantation: Evolution of a Surgical Technique

    PubMed Central

    Islam, Ana K.; 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 < 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. PMID:27478630

  16. Reduced dissemination of circulating tumor cells with no-touch isolation surgical technique in patients with pancreatic cancer.

    PubMed

    Gall, Tamara M H; Jacob, Jimmy; Frampton, Adam E; Krell, Jonathan; Kyriakides, Charis; Castellano, Leandro; Stebbing, Justin; Jiao, Long R

    2014-05-01

    Circulating tumor cells (CTCs) disseminate from the primary tumor and travel through the bloodstream and lymphatic system. The detection of and/or increase in the number of CTCs during a patient’s clinical course may be a harbinger of forthcoming overt metastasis. We aimed to examine the impact of 2 different surgical techniques, standard (ST) pancreaticoduodenectomy (PD) and no-touch isolation (NT) PD, on tumor behavior and outcome in patients with pancreatic cancer by using CTCs as biomarkers. In this pilot study, patients were randomized to either ST-PD (n = 6) or NT-PD (n = 6). Intraoperatively, blood samples were taken from the portal vein for measurement of CTCs before and immediately after removal of the tumor. An increase in CTCs was seen in 5 of 6 patients (83%) with ST-PD but no patients with NT-PD (P = .003). In the ST-PD and NT-PD groups, median overall survival was 13.0 and 16.7 months, respectively (P = .33); there was no difference in disease-free survival (P = .42). The use of NT-PD significantly reduced the number of CTCs in the portal vein with no benefit in survival outcomes compared with ST-PD, although more extensive studies are required. PMID:24599353

  17. Decomposition technique and optimal trajectories for the aeroassisted flight experiment

    NASA Technical Reports Server (NTRS)

    Miele, A.; Wang, T.; Deaton, A. W.

    1990-01-01

    An actual geosynchronous Earth orbit-to-low Earth orbit (GEO-to-LEO) transfer is considered with reference to the aeroassisted flight experiment (AFE) spacecraft, and optimal trajectories are determined by minimizing the total characteristic velocity. The optimization is performed with respect to the time history of the controls (angle of attack and angle of bank), the entry path inclination and the flight time being free. Two transfer maneuvers are considered: direct ascent (DA) to LEO and indirect ascent (IA) to LEO via parking Earth orbit (PEO). By taking into account certain assumptions, the complete system can be decoupled into two subsystems: one describing the longitudinal motion and one describing the lateral motion. The angle of attack history, the entry path inclination, and the flight time are determined via the longitudinal motion subsystem. In this subsystem, the difference between the instantaneous bank angle and a constant bank angle is minimized in the least square sense subject to the specified orbital inclination requirement. Both the angles of attack and the angle of bank are shown to be constant. This result has considerable importance in the design of nominal trajectories to be used in the guidance of AFE and aeroassisted orbital transfer (AOT) vehicles.

  18. Surgical approaches for the management of idiopathic thoracic scoliosis and the indications for combined anterior-posterior technique.

    PubMed

    Rauzzino, M J; Shaffrey, C I; Wagner, J; Nockels, R; Abel, M

    1999-05-15

    The indications for surgical intervention in patients with idiopathic scoliosis have been well defined. The goals of surgery are to achieve fusion and arrest progressive curvature while restoring normal coronal and sagittal balance. As first introduced by Harrington, posterior fusion, the gold standard of treatment, has a proven record of success. More recently, anterior techniques for performing fusion procedures via either a thoracotomy or a retroperitoneal approach have been popularized in attempts to achieve better correction of curvature, preserve motion segments, and avoid some of the complications of posterior fusion such as the development of the flat-back syndrome. Anterior instrumentation alone, although effective, can be kyphogenic and has been shown to be associated with complications such as pseudarthrosis and instrumentation failure. Performing a combined approach in patients with scoliosis and other deformities has become an increasingly popular procedure to achieve superior correction of deformity and to minimize later complications. Indications for a combined approach (usually consisting of anterior release, arthrodesis with or without use of instrumentation, and posterior segmental fusion) include: prevention of crankshaft phenomenon in juvenile or skeletally immature adolescents; correction of large curves (75 degrees ) or excessively rigid curves in skeletally mature or immature patients; correction of curves with large sagittal-plane deformities such as thoracic kyphosis (> 90 degrees ) or thoracic lordosis (> 20 degrees ); and correction of thoracolumbar curves that need to be fused to the sacrum. Surgery may be performed either in a staged proceedure or, more commonly, in a single sitting. The authors discuss techniques for combined surgery and complication avoidance. PMID:17031912

  19. First Robotic-Assisted Dual Kidney Transplant: Surgical Technique and Report of a Case With 24-month Follow-up

    PubMed Central

    Frongia, Mauro; Cadoni, Rossano; Solinas, Andrea

    2015-01-01

    Background Open surgery is the gold standard procedure for kidney transplantation. There is a strong rationale for using minimally invasive surgery in patients with end-stage renal disease. A robotic-assisted dual kidney transplant was performed for the first time at our institution. Methods In August 2013, a 63-year-old man with end-stage renal disease and diabetes mellitus under pharmacological control received both kidneys from a 70-year-old marginal donor. Pretransplant donor biopsy demonstrated a bilateral Karpinski score greater than 5. The organs did not exhibit malformations and each had an artery and a vein. The procedure was carried out by a 7-port intraperitoneal approach using the da Vinci surgical system. The procedure was identical for the 2 kidneys except that mobilization of the sigmoid colon was required to introduce the left graft. The renal vessels were anastomosed to the left external iliac vessels. The novel aspect of the technique was the introduction of both grafts through a single, 7-cm upper midline incision. Results Total operative time was 400 minutes and blood loss was 120 mL. Both grafts immediately began functioning. There were no intraoperative or postoperative complications. The patient was discharged on the seventh postoperative day with normal renal function. At 24 months, he is well and does not require hemodialysis. Conclusions Minimally invasive robotic-assisted technology is a promising technique that provides exceptional patient outcomes by reducing operative morbidity, immobilization, and time to recovery, while affording better esthetic results. Selected patients with multiple comorbidities benefit most. Grafts from marginal donors are an extremely valuable resource. PMID:27500234

  20. Optimized distortion correction technique for echo planar imaging.

    PubMed

    Chen, N K; Wyrwicz, A M

    2001-03-01

    A new phase-shifted EPI pulse sequence is described that encodes EPI phase errors due to all off-resonance factors, including B(o) field inhomogeneity, eddy current effects, and gradient waveform imperfections. Combined with the previously proposed multichannel modulation postprocessing algorithm (Chen and Wyrwicz, MRM 1999;41:1206-1213), the encoded phase error information can be used to effectively remove geometric distortions in subsequent EPI scans. The proposed EPI distortion correction technique has been shown to be effective in removing distortions due to gradient waveform imperfections and phase gradient-induced eddy current effects. In addition, this new method retains advantages of the earlier method, such as simultaneous correction of different off-resonance factors without use of a complicated phase unwrapping procedure. The effectiveness of this technique is illustrated with EPI studies on phantoms and animal subjects. Implementation to different versions of EPI sequences is also described. Magn Reson Med 45:525-528, 2001. PMID:11241714

  1. Surgical Management of Oro-Antral Communications Using Resorbable GTR Membrane and FDMB Sandwich Technique: A Clinical Study.

    PubMed

    Sandhya, G; Reddy, P Bal; Kumar, K A Jeevan; Sridhar Reddy, B; Prasad, N; Kiran, G

    2013-09-01

    The paper describes a new technique for closure of the oro-antral communication, in which both hard (bone) and soft tissue closure was achieved. The technique uses a Guided Tissue Regeeration (GTR) membrane and Freez Dried Mineralized Bone (FDMB) allograft for closure of the defect. Aim of the study was to assess the advantages of the surgical management of oro-antral communications using resorbable GTR membrane and FDMB sandwich technique. A total 10 patients were selected in whom dental extractions were complicated by formation of oro-antral communication (OAC). The resorbable guided tissue regeneration membrane (PERIOCOL-GTR) and freeze dried mineralized bone allograft material was used. Some cancellous granules of freeze dried bone allograft was sandwiched between sheaths of appropriately trimmed collagen membrane which was previously sutured together on three sides using 3/0 resorbable polyglycolic acid suture (vicryl). The fourth side was then adequately closed using the same suture after the bone graft had been inserted, thus creating a closed sandwich. The prepared sandwich was then tucked into the OAC in such a way that it formed a convexity towards the sinus and a concavity towards the alveolar bone. The rough surface of the sandwich is faced to the alveolar bone and additional bone graft is filled into this concavity. Suturing done without tension. Post-operative orthopantomogram was taken to radiologically quantify the amount of bone grafting/augmentation and closure of oro-antral fistula. There was an average of 11.84 mm bone formation after 6 months, the average width preserved and obtained was 6.9 mm. By the end of 4 months there was evidence of bone formation in 7 subjects and in three subjects bony trabeculae formed was almost similar to the adjacent bone. By the end of 6 months follow-up of 7 subjects showed trabeculae indistinguishable from the adjacent bone. The study was done in 10 patients with a follow-up period of 6 months and found to

  2. A technique for optimizing the design of power semiconductor devices

    NASA Technical Reports Server (NTRS)

    Schlegel, E. S.

    1976-01-01

    A technique is described that provides a basis for predicting whether any device design change will improve or degrade the unavoidable trade-off that must be made between the conduction loss and the turn-off speed of fast-switching high-power thyristors. The technique makes use of a previously reported method by which, for a given design, this trade-off was determined for a wide range of carrier lifetimes. It is shown that by extending this technique, one can predict how other design variables affect this trade-off. The results show that for relatively slow devices the design can be changed to decrease the current gains to improve the turn-off time without significantly degrading the losses. On the other hand, for devices having fast turn-off times design changes can be made to increase the current gain to decrease the losses without a proportionate increase in the turn-off time. Physical explanations for these results are proposed.

  3. Intraocular Lens-Shell Technique: Adjustment of the Surgical Procedure Leads to Greater Safety When Treating Dense Nuclear Cataracts

    PubMed Central

    Chen, Weirong; Qu, Bo; Zhang, Xinyu; Lin, Zhuoling; Chen, Jingjing; Liu, Yizhi

    2014-01-01

    Objective To compare the efficacy and safety of the intraocular lens (IOL)-shell procedure versus conventional phacoemulsification for the surgical treatment of dense cataracts. Methods Eighty eyes with dense nuclear cataracts were enrolled in a prospective, randomized controlled study. Patients were assigned to two groups. In Group I, the IOL was traditionally implanted after all nuclear fragments were completely removed, and in Group II, the IOL was innovatively implanted in the bag before the last residual nuclear fragment was removed. This novel adjusted surgical procedure, named the “IOL-shell technique”, features use of the IOL as a protective barrier rather than simply as a refractive alternative, and it is conceptually different from the traditional step-by-step procedure. Clinical examinations, including uncorrected visual acuity, central corneal thickness (CCT), temporal clear corneal incision thickness and corneal endothelial cell density, were carried out. Results The inter-group difference in temporal corneal thickness was found to be of no statistical significance at any of the visits. Compared to eyes in Group I, those in Group II were shown to have significantly less corneal endothelial cell loss on both the 7th and 30th day following surgery. At 7 days after surgery, the mean corneal endothelial cell loss in Group II was 10.29%, compared to 14.37% in Group I (P<0.05). The mean endothelial cell loss measured on postoperative day 30 was 16.88% in Group II compared to 23.32% in Group I (P<0.05). On the 1st day after surgery, the mean CCT of eyes in Group II was significantly smaller compared to Group I (Group I vs. Group II: 19.42% vs. 13.50%, P<0.05). Conclusions Compared to conventional phacoemulsification, the IOL-shell technique was shown to be a relatively safer procedure without compromised efficiency for dense cataracts, and it caused less corneal endothelial cell loss and milder postoperative corneal edema (Clinical Trials Identifier: NCT

  4. Abortion - surgical

    MedlinePlus

    Suction curettage; Surgical abortion; Elective abortion - surgical; Therapeutic abortion - surgical ... problem. Your pregnancy is harmful to your health (therapeutic abortion). The pregnancy resulted after a traumatic event ...

  5. Computer-assisted design and computer-assisted modeling technique optimization and advantages over traditional methods of osseous flap reconstruction.

    PubMed

    Matros, Evan; Albornoz, Claudia R; Rensberger, Michael; Weimer, Katherine; Garfein, Evan S

    2014-06-01

    There is increased clinical use of computer-assisted design (CAD) and computer-assisted modeling (CAM) for osseous flap reconstruction, particularly in the head and neck region. Limited information exists about methods to optimize the application of this new technology and for cases in which it may be advantageous over existing methods of osseous flap shaping. A consecutive series of osseous reconstructions planned with CAD/CAM over the past 5 years was analyzed. Conceptual considerations and refinements in the CAD/CAM process were evaluated. A total of 48 reconstructions were performed using CAD/CAM. The majority of cases were performed for head and neck tumor reconstruction or related complications whereas the remainder (4%) were performed for penetrating trauma. Defect location was the mandible (85%), maxilla (12.5%), and pelvis (2%). Reconstruction was performed immediately in 73% of the cases and delayed in 27% of the cases. The mean number of osseous flap bone segments used in reconstruction was 2.41. Areas of optimization include the following: mandible cutting guide placement, osteotomy creation, alternative planning, and saw blade optimization. Identified benefits of CAD/CAM over current techniques include the following: delayed timing, anterior mandible defects, specimen distortion, osteotomy creation in three dimensions, osteotomy junction overlap, plate adaptation, and maxillary reconstruction. Experience with CAD/CAM for osseous reconstruction has identified tools for technique optimization and cases where this technology may prove beneficial over existing methods. Knowledge of these facts may contribute to improved use and main-stream adoption of CAD/CAM virtual surgical planning by reconstructive surgeons. PMID:24323480

  6. The clinical application of the sliding loop technique for renorrhaphy during robot-assisted laparoscopic partial nephrectomy: Surgical technique and outcomes

    PubMed Central

    Kim, Hyung Suk; Lee, Young Ju; Ku, Ja Hyeon; Kwak, Cheol; Kim, Hyeon Hoe

    2015-01-01

    Purpose To report the initial clinical outcomes of the newly devised sliding loop technique (SLT) used for renorrhaphy in patients who underwent robot-assisted laparoscopic partial nephrectomy (RALPN) for small renal mass. Materials and Methods We reviewed the surgical videos and medical charts of 31 patients who had undergone RALPN with the SLT renorrhaphy performed by two surgeons (CWJ and CK) between January 2014 and October 2014. SLT renorrhaphy was performed after tumor excision and renal parenchymal defect repair. Assessed outcomes included renorrhaphy time (RT), warm ischemic time, perioperative complications, and perioperative renal function change. RT was defined as interval from the end of bed suture to the renal artery declamping. Results In all patients, sliding loop renorrhaphy was successfully conducted without conversions to radical nephrectomy or open approaches. Mean renorrhaphy and warm ischemic time were 9.0 and 22.6 minutes, respectively. After completing renorrhaphy, there were no adverse events such as dehiscence of approximated renal parenchyma, renal parenchymal tearing, or significant bleeding. Furthermore, no postoperative complications or significant renal function decline were observed as of the last follow-up for all patients. The limitations of this study include the small volume case series, the retrospective nature of the study, and the heterogeneity of surgeons. Conclusions From our initial clinical experience, SLT may be an efficient and safe renorrhaphy method in real clinical practice. Further large scale, prospective, long-term follow-up, and direct comparative studies with other techniques are required to confirm the clinical applicability of SLT. PMID:26568794

  7. An Enhanced Multi-Objective Optimization Technique for Comprehensive Aerospace Design

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Aditi; Rajadas, John N.

    2000-01-01

    An enhanced multiobjective formulation technique, capable of emphasizing specific objective functions during the optimization process, has been demonstrated on a complex multidisciplinary design application. The Kreisselmeier-Steinhauser (K-S) function approach, which has been used successfully in a variety of multiobjective optimization problems, has been modified using weight factors which enables the designer to emphasize specific design objectives during the optimization process. The technique has been implemented in two distinctively different problems. The first is a classical three bar truss problem and the second is a high-speed aircraft (a doubly swept wing-body configuration) application in which the multiobjective optimization procedure simultaneously minimizes the sonic boom and the drag-to-lift ratio (C(sub D)/C(sub L)) of the aircraft while maintaining the lift coefficient within prescribed limits. The results are compared with those of an equally weighted K-S multiobjective optimization. Results demonstrate the effectiveness of the enhanced multiobjective optimization procedure.

  8. Investigation on the use of optimization techniques for helicopter airframe vibrations design studies

    NASA Technical Reports Server (NTRS)

    Sreekanta Murthy, T.

    1992-01-01

    Results of the investigation of formal nonlinear programming-based numerical optimization techniques of helicopter airframe vibration reduction are summarized. The objective and constraint function and the sensitivity expressions used in the formulation of airframe vibration optimization problems are presented and discussed. Implementation of a new computational procedure based on MSC/NASTRAN and CONMIN in a computer program system called DYNOPT for optimizing airframes subject to strength, frequency, dynamic response, and dynamic stress constraints is described. An optimization methodology is proposed which is thought to provide a new way of applying formal optimization techniques during the various phases of the airframe design process. Numerical results obtained from the application of the DYNOPT optimization code to a helicopter airframe are discussed.

  9. Optimization of hydrostatic transmissions by means of virtual instrumentation technique

    NASA Astrophysics Data System (ADS)

    Ion Guta, Dragos Daniel; Popescu, Teodor Costinel; Dumitrescu, Catalin

    2010-11-01

    Obtaining mathematical models, as close as possible to physical phenomena which are intended to be replicated or improved, help us in deciding how to optimize them. The introduction of computers in monitoring and controlling processes caused changes in technological systems. With support from the methods for identification of processes and from the power of numerical computing equipment, researchers and designers can shorten the period for development of applications in various fields by generating a solution as close as possible to reality, since the design stage [1]. The paper presents a hybrid solution of modeling / simulation of a hydrostatic transmission with mixed adjustment. For simulation and control of the examined process we have used two distinct environments, AMESim and LabVIEW. The proposed solution allows coupling of the system's model to the software control modules developed using virtual instrumentation. Simulation network of the analyzed system was "tuned" and validated by an actual model of the process. This paper highlights some aspects regarding energy and functional advantages of hydraulic transmissions based on adjustable volumetric machines existing in their primary and secondary sectors [2].

  10. Abortion - surgical

    MedlinePlus

    Suction curettage; Surgical abortion; Elective abortion - surgical; Therapeutic abortion - surgical ... Surgical abortion involves dilating the opening to the uterus (cervix) and placing a small suction tube into the uterus. ...

  11. Comparison of Artificial Immune System and Particle Swarm Optimization Techniques for Error Optimization of Machine Vision Based Tool Movements

    NASA Astrophysics Data System (ADS)

    Mahapatra, Prasant Kumar; Sethi, Spardha; Kumar, Amod

    2015-10-01

    In conventional tool positioning technique, sensors embedded in the motion stages provide the accurate tool position information. In this paper, a machine vision based system and image processing technique for motion measurement of lathe tool from two-dimensional sequential images captured using charge coupled device camera having a resolution of 250 microns has been described. An algorithm was developed to calculate the observed distance travelled by the tool from the captured images. As expected, error was observed in the value of the distance traversed by the tool calculated from these images. Optimization of errors due to machine vision system, calibration, environmental factors, etc. in lathe tool movement was carried out using two soft computing techniques, namely, artificial immune system (AIS) and particle swarm optimization (PSO). The results show better capability of AIS over PSO.

  12. Calculation of free fall trajectories based on numerical optimization techniques

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The development of a means of computing free-fall (nonthrusting) trajectories from one specified point in the solar system to another specified point in the solar system in a given amount of time was studied. The problem is that of solving a two-point boundary value problem for which the initial slope is unknown. Two standard methods of attack exist for solving two-point boundary value problems. The first method is known as the initial value or shooting method. The second method of attack for two-point boundary value problems is to approximate the nonlinear differential equations by an appropriate linearized set. Parts of both boundary value problem solution techniques described above are used. A complete velocity history is guessed such that the corresponding position history satisfies the given boundary conditions at the appropriate times. An iterative procedure is then followed until the last guessed velocity history and the velocity history obtained from integrating the acceleration history agree to some specified tolerance everywhere along the trajectory.

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

    NASA Astrophysics Data System (ADS)

    Salathe, Marco; Kihm, Thomas

    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.

  14. A technique for locating function roots and for satisfying equality constraints in optimization

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1991-01-01

    A new technique for locating simultaneous roots of a set of functions is described. The technique is based on the property of the Kreisselmeier-Steinhauser function which descends to a minimum at each root location. It is shown that the ensuing algorithm may be merged into any nonlinear programming method for solving optimization problems with equality constraints.

  15. A technique for locating function roots and for satisfying equality constraints in optimization

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, J.

    1992-01-01

    A new technique for locating simultaneous roots of a set of functions is described. The technique is based on the property of the Kreisselmeier-Steinhauser function which descends to a minimum at each root location. It is shown that the ensuing algorithm may be merged into any nonlinear programming method for solving optimization problems with equality constraints.

  16. Practical Framework for an Electron Beam Induced Current Technique Based on a Numerical Optimization Approach

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Hideshi; Soeda, Takeshi

    2015-03-01

    A practical framework for an electron beam induced current (EBIC) technique has been established for conductive materials based on a numerical optimization approach. Although the conventional EBIC technique is useful for evaluating the distributions of dopants or crystal defects in semiconductor transistors, issues related to the reproducibility and quantitative capability of measurements using this technique persist. For instance, it is difficult to acquire high-quality EBIC images throughout continuous tests due to variation in operator skill or test environment. Recently, due to the evaluation of EBIC equipment performance and the numerical optimization of equipment items, the constant acquisition of high contrast images has become possible, improving the reproducibility as well as yield regardless of operator skill or test environment. The technique proposed herein is even more sensitive and quantitative than scanning probe microscopy, an imaging technique that can possibly damage the sample. The new technique is expected to benefit the electrical evaluation of fragile or soft materials along with LSI materials.

  17. A damage identification technique based on embedded sensitivity analysis and optimization processes

    NASA Astrophysics Data System (ADS)

    Yang, Chulho; Adams, Douglas E.

    2014-07-01

    A vibration based structural damage identification method, using embedded sensitivity functions and optimization algorithms, is discussed in this work. The embedded sensitivity technique requires only measured or calculated frequency response functions to obtain the sensitivity of system responses to each component parameter. Therefore, this sensitivity analysis technique can be effectively used for the damage identification process. Optimization techniques are used to minimize the difference between the measured frequency response functions of the damaged structure and those calculated from the baseline system using embedded sensitivity functions. The amount of damage can be quantified directly in engineering units as changes in stiffness, damping, or mass. Various factors in the optimization process and structural dynamics are studied to enhance the performance and robustness of the damage identification process. This study shows that the proposed technique can improve the accuracy of damage identification with less than 2 percent error of estimation.

  18. [The surgical verification of the periodontal probe and endoral radiography in assessing the bone substance loss in periodontal disease. A proposal for optimizing the methods].

    PubMed

    Bianchi, S D; Barone Monfrin, S; Damilano, G P; Bellocchio, G

    1990-11-01

    It is difficult to compare levels of bone loss in periodontal disease measured by periodontal probe and X-ray and to verify them versus surgical techniques. In fact, there are relatively few published reports on the subject. To this purpose the Authors describe their personal experience using plates equipped with guide tracks and center-film boxes with personalized bites. The suitability of the two methods (probe, intraoral X-ray) to determine levels of bone loss similar to those revealed by surgical verification was assessed on the basis of an analysis of the respective bone loss in 44 sites surrounding 19 dental elements. This method, which is accurate but time-consuming, demonstrated an broadly analogous underestimate (approx. 20%) using both preoperative probe and X-ray techniques in comparison to the true level of bone loss measured during surgery. PMID:2084527

  19. Optimizing molecular properties using a relative index of thermodynamic stability and global optimization techniques.

    PubMed

    Fournier, René; Mohareb, Amir

    2016-01-14

    We devised a global optimization (GO) strategy for optimizing molecular properties with respect to both geometry and chemical composition. A relative index of thermodynamic stability (RITS) is introduced to allow meaningful energy comparisons between different chemical species. We use the RITS by itself, or in combination with another calculated property, to create an objective function F to be minimized. Including the RITS in the definition of F ensures that the solutions have some degree of thermodynamic stability. We illustrate how the GO strategy works with three test applications, with F calculated in the framework of Kohn-Sham Density Functional Theory (KS-DFT) with the Perdew-Burke-Ernzerhof exchange-correlation. First, we searched the composition and configuration space of CmHnNpOq (m = 0-4, n = 0-10, p = 0-2, q = 0-2, and 2 ≤ m + n + p + q ≤ 12) for stable molecules. The GO discovered familiar molecules like N2, CO2, acetic acid, acetonitrile, ethane, and many others, after a small number (5000) of KS-DFT energy evaluations. Second, we carried out a GO of the geometry of CumSnn (+) (m = 1, 2 and n = 9-12). A single GO run produced the same low-energy structures found in an earlier study where each CumSnn (+) species had been optimized separately. Finally, we searched bimetallic clusters AmBn (3 ≤ m + n ≤ 6, A,B= Li, Na, Al, Cu, Ag, In, Sn, Pb) for species and configurations having a low RITS and large highest occupied Molecular Orbital (MO) to lowest unoccupied MO energy gap (Eg). We found seven bimetallic clusters with Eg > 1.5 eV. PMID:26772561

  20. Optimizing molecular properties using a relative index of thermodynamic stability and global optimization techniques

    NASA Astrophysics Data System (ADS)

    Fournier, René; Mohareb, Amir

    2016-01-01

    We devised a global optimization (GO) strategy for optimizing molecular properties with respect to both geometry and chemical composition. A relative index of thermodynamic stability (RITS) is introduced to allow meaningful energy comparisons between different chemical species. We use the RITS by itself, or in combination with another calculated property, to create an objective function F to be minimized. Including the RITS in the definition of F ensures that the solutions have some degree of thermodynamic stability. We illustrate how the GO strategy works with three test applications, with F calculated in the framework of Kohn-Sham Density Functional Theory (KS-DFT) with the Perdew-Burke-Ernzerhof exchange-correlation. First, we searched the composition and configuration space of CmHnNpOq (m = 0-4, n = 0-10, p = 0-2, q = 0-2, and 2 ≤ m + n + p + q ≤ 12) for stable molecules. The GO discovered familiar molecules like N2, CO2, acetic acid, acetonitrile, ethane, and many others, after a small number (5000) of KS-DFT energy evaluations. Second, we carried out a GO of the geometry of Cu m Snn + (m = 1, 2 and n = 9-12). A single GO run produced the same low-energy structures found in an earlier study where each Cu m S nn + species had been optimized separately. Finally, we searched bimetallic clusters AmBn (3 ≤ m + n ≤ 6, A,B= Li, Na, Al, Cu, Ag, In, Sn, Pb) for species and configurations having a low RITS and large highest occupied Molecular Orbital (MO) to lowest unoccupied MO energy gap (Eg). We found seven bimetallic clusters with Eg > 1.5 eV.

  1. Parameter Optimization in an atmospheric GCM using the Simultaneous Perturbation Stochastic Approximation (SPSA) technique

    NASA Astrophysics Data System (ADS)

    Agarwal, Reema; Köhl, Armin; Stammer, Detlef

    2013-04-01

    We present an application of a multivariate parameter optimization technique to a global primitive equation Atmospheric GCM. The technique is based upon the Simultaneous Perturbation Stochastic Approximation (SPSA) algorithm, in which gradients of the objective function are approximated. This technique has some advantages over other optimization procedures (such as Green's function or the Adjoint methods) like robustness to noise in the objective function and ability to find the actual minimum in case of multiple minima. Another useful feature of the technique is its simplicity and cost effectiveness. The atmospheric GCM used is the coarse resolution PLAnet SIMulator (PLASIM). In order to identify the parameters to be used in the optimization procedure, a series of sensitivity experiments with 12 different parameters was performed and subsequently 5 parameters related to cloud radiation parameterization to which the GCM was highly sensitive were finally selected. The optimization technique is applied and the selected parameters were simultaneously tuned and tested for a period of 1-year GCM integrations. The performance of the technique is judged by the behavior of model's cost function, which includes temperature, precipitation, humidity and flux contributions. The method is found to be useful for reducing the model's cost function against both identical twin data as well as ECMWF ERA-40 reanalysis data.

  2. Cost-Optimal Design of a 3-Phase Core Type Transformer by Gradient Search Technique

    NASA Astrophysics Data System (ADS)

    Basak, R.; Das, A.; Sensarma, A. K.; Sanyal, A. N.

    2014-04-01

    3-phase core type transformers are extensively used as power and distribution transformers in power system and their cost is a sizable proportion of the total system cost. Therefore they should be designed cost-optimally. The design methodology for reaching cost-optimality has been discussed in details by authors like Ramamoorty. It has also been discussed in brief in some of the text-books of electrical design. The paper gives a method for optimizing design, in presence of constraints specified by the customer and the regulatory authorities, through gradient search technique. The starting point has been chosen within the allowable parameter space the steepest decent path has been followed for convergence. The step length has been judiciously chosen and the program has been maneuvered to avoid local minimal points. The method appears to be best as its convergence is quickest amongst different optimizing techniques.

  3. A knowledge-based approach to improving optimization techniques in system planning

    NASA Technical Reports Server (NTRS)

    Momoh, J. A.; Zhang, Z. Z.

    1990-01-01

    A knowledge-based (KB) approach to improve mathematical programming techniques used in the system planning environment is presented. The KB system assists in selecting appropriate optimization algorithms, objective functions, constraints and parameters. The scheme is implemented by integrating symbolic computation of rules derived from operator and planner's experience and is used for generalized optimization packages. The KB optimization software package is capable of improving the overall planning process which includes correction of given violations. The method was demonstrated on a large scale power system discussed in the paper.

  4. Application of response surface techniques to helicopter rotor blade optimization procedure

    NASA Technical Reports Server (NTRS)

    Henderson, Joseph Lynn; Walsh, Joanne L.; Young, Katherine C.

    1995-01-01

    In multidisciplinary optimization problems, response surface techniques can be used to replace the complex analyses that define the objective function and/or constraints with simple functions, typically polynomials. In this work a response surface is applied to the design optimization of a helicopter rotor blade. In previous work, this problem has been formulated with a multilevel approach. Here, the response surface takes advantage of this decomposition and is used to replace the lower level, a structural optimization of the blade. Problems that were encountered and important considerations in applying the response surface are discussed. Preliminary results are also presented that illustrate the benefits of using the response surface.

  5. Scalable Clustering of High-Dimensional Data Technique Using SPCM with Ant Colony Optimization Intelligence.

    PubMed

    Srinivasan, Thenmozhi; Palanisamy, Balasubramanie

    2015-01-01

    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. PMID:26495413

  6. Scalable Clustering of High-Dimensional Data Technique Using SPCM with Ant Colony Optimization Intelligence

    PubMed Central

    Srinivasan, Thenmozhi; Palanisamy, Balasubramanie

    2015-01-01

    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. PMID:26495413

  7. Gradient-based multiobjective optimization using a distance constraint technique and point replacement

    NASA Astrophysics Data System (ADS)

    Sato, Yuki; Izui, Kazuhiro; Yamada, Takayuki; Nishiwaki, Shinji

    2016-07-01

    This paper proposes techniques to improve the diversity of the searching points during the optimization process in an Aggregative Gradient-based Multiobjective Optimization (AGMO) method, so that well-distributed Pareto solutions are obtained. First to be discussed is a distance constraint technique, applied among searching points in the objective space when updating design variables, that maintains a minimum distance between the points. Next, a scheme is introduced that deals with updated points that violate the distance constraint, by deleting the offending points and introducing new points in areas of the objective space where searching points are sparsely distributed. Finally, the proposed method is applied to example problems to illustrate its effectiveness.

  8. The use of singular value gradients and optimization techniques to design robust controllers for multiloop systems

    NASA Technical Reports Server (NTRS)

    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.

  9. Optimization of Heat-Sink Cooling Structure in EAST with Hydraulic Expansion Technique

    NASA Astrophysics Data System (ADS)

    Xu, Tiejun; Huang, Shenghong; Xie, Han; Song, Yuntao; Zhan, Ping; Ji, Xiang; Gao, Daming

    2011-12-01

    Considering utilization of the original chromium-bronze material, two processing techniques including hydraulic expansion and high temperature vacuum welding were proposed for the optimization of heat-sink structure in EAST. The heat transfer performance of heat-sink with or without cooling tube was calculated and different types of connection between tube and heat-sink were compared by conducting a special test. It is shown from numerical analysis that the diameter of heat-sink channel can be reduced from 12 mm to 10 mm. Compared with the original sample, the thermal contact resistance between tube and heat-sink for welding sample can reduce the heat transfer performance by 10%, while by 20% for the hydraulic expansion sample. However, the welding technique is more complicated and expensive than hydraulic expansion technique. Both the processing technique and the heat transfer performance of heat-sink prototype should be further considered for the optimization of heat-sink structure in EAST.

  10. A technique for optimally designing engineering structures with manufacturing tolerances accounted for

    NASA Astrophysics Data System (ADS)

    Tabakov, P. Y.; Walker, M.

    2007-01-01

    Accurate optimal design solutions for most engineering structures present considerable difficulties due to the complexity and multi-modality of the functional design space. The situation is made even more complex when potential manufacturing tolerances must be accounted for in the optimizing process. The present study provides an in-depth analysis of the problem, and then a technique for determining the optimal design of engineering structures, with manufacturing tolerances in the design variables accounted for, is proposed and demonstrated. The examples used to demonstrate the technique involve the design optimization of simple fibre-reinforced laminated composite structures. The technique is simple, easy to implement and, at the same time, very efficient. It is assumed that the probability of any tolerance value occurring within the tolerance band, compared with any other, is equal, and thus it is a worst-case scenario approach. In addition, the technique is non-probabilistic. A genetic algorithm with fitness sharing, including a micro-genetic algorithm, has been found to be very suitable to use, and implemented in the technique. The numerical examples presented in the article deal with buckling load design optimization of an laminated angle ply plate, and evaluation of the maximum burst pressure in a thick laminated anisotropic pressure vessel. Both examples clearly demonstrate the impact of manufacturing tolerances on the overall performance of a structure and emphasize the importance of accounting for such tolerances in the design optimization phase. This is particularly true of the pressure vessel. The results show that when the example tolerances are accounted for, the maximum design pressure is reduced by 60.2% (in the case of a single layer vessel), and when five layers are specified, if the nominal fibre orientations are implemented and the example tolerances are incurred during fabrication, the actual design pressure could be 64% less than predicted.

  11. Use of Ilizarov Fixator for Grade III B Open Olecranon Fracture: a Case Report and Surgical Technique

    PubMed Central

    Sharad Nemade, Pradip; Dash, Kumar Kaushik; Patwardhan, Tanvi Yeshwant; Londhe, Pravin Vasant

    2015-01-01

    Introduction: External fixator application can be difficult for olecranon fractures in presence of large degloving injuries. We describe use of simple Ilizarov ring fixator construct for grade IIIB open olecranon fracture management. Case Report: A 45-year-old female with Grade III B open comminuted olecranon fracture (30*15cm degloving area) and ulnar nerve palsy was treated with a novel ring fixator construct. Two cut-end olive wires were passed from the proximal olecranon across the fracture site in intramedullary fashion exiting dorsally at mid-ulnar level through healthy skin and were attached to an Ilizarov half ring secured by perpendicular wires. The olive wires were tensioned, achieving compression and stability. Range of motion (ROM) exercises could be started quickly as the elbow was not spanned. Wound healed after skin grafting and at one-year follow-up the patient has good functional results (PRE 7, DASH 9.48), elbow ROM 10°-130°, 75° pronation and 85° supination. The patient returned to pre-injury occupational activities and had no pain. At three-year follow-up, the x-ray and CT showed union of olecranon fragment with well-maintained congruency. Conclusion: Internal fixation in most cases may be precluded by the soft tissue trauma and risk of infection. In addition, the small proximal fragment precludes a stable external fixation. In this technique, the hardware is kept away from the open wound allowing better wound inspection and care. The intramedullary olive wires provide compression and stability, and thus allow early ROM. Ilizarov half-ring and olive wire fixation can be an useful option for management of high grade open olecranon fractures because of its advantages, viz. stable fixation, minimal internal hardware, optimal wound care, immediate initiation of range of motion, and good outcome. PMID:27299012

  12. Early results from an angiosome-directed open surgical technique for venous arterialization in patients with critical lower limb ischemia

    PubMed Central

    Houlind, Kim; Christensen, Johnny; Hallenberg, Christian; Jepsen, Jørn M.

    2013-01-01

    Background Patients with critical lower limb ischemia without patent pedal arteries cannot be treated by the conventional arterial reconstruction. Venous arterialization has been suggested to improve limb salvage in this subgroup of patients but has not gained wide acceptance. We report our early experience after implementing deep and superficial venous arterialization of the lower limb. Materials and methods Ten patients with critical ischemia and without crural or pedal arteries available for conventional bypass surgery or angioplasty were treated with distal venous arterialization. Inflow was from the most distal unobstructed segment. Run-off was the dorsal pedal venous arch (n=5), the dorsal pedal venous arch and a concomitant vein of the posterior tibial artery (n=3), or the dorsal pedal venous arch and a concomitant vein of the common plantar artery (n=2) depending on the location of the ischemic lesion. Venous valves were destroyed using antegrade valvulotomes, guide wires, knob needles, or retrograde valvulotomes via an extra incision. Results Seven of the operated limbs were amputated after 23 (1–256) days (median [range]). The main reasons for amputation were lack of healing of either the original wound, of incisional wounds on the foot, or persisting pain at rest. In three cases, the bypass was open at the time of amputation. Two patients experienced complete wound healing after 231 and 342 days, respectively. By the end of follow-up, the last patient was ambulating with slow wound healing but without pain 309 days after surgery. Conclusion Venous arterialization may be used as a treatment of otherwise unsalveable limbs. The success rate is, however, limited. Technical optimization of the technique is warranted. PMID:24358432

  13. A technique optimization protocol and the potential for dose reduction in digital mammography

    SciTech Connect

    Ranger, Nicole T.; Lo, Joseph Y.; Samei, Ehsan

    2010-03-15

    Digital mammography requires revisiting techniques that have been optimized for prior screen/film mammography systems. The objective of the study was to determine optimized radiographic technique for a digital mammography system and demonstrate the potential for dose reduction in comparison to the clinically established techniques based on screen- film. An objective figure of merit (FOM) was employed to evaluate a direct-conversion amorphous selenium (a-Se) FFDM system (Siemens Mammomat Novation{sup DR}, Siemens AG Medical Solutions, Erlangen, Germany) and was derived from the quotient of the squared signal-difference-to-noise ratio to mean glandular dose, for various combinations of technique factors and breast phantom configurations including kilovoltage settings (23-35 kVp), target/filter combinations (Mo-Mo and W-Rh), breast-equivalent plastic in various thicknesses (2-8 cm) and densities (100% adipose, 50% adipose/50% glandular, and 100% glandular), and simulated mass and calcification lesions. When using a W-Rh spectrum, the optimized FOM results for the simulated mass and calcification lesions showed highly consistent trends with kVp for each combination of breast density and thickness. The optimized kVp ranged from 26 kVp for 2 cm 100% adipose breasts to 30 kVp for 8 cm 100% glandular breasts. The use of the optimized W-Rh technique compared to standard Mo-Mo techniques provided dose savings ranging from 9% for 2 cm thick, 100% adipose breasts, to 63% for 6 cm thick, 100% glandular breasts, and for breasts with a 50% adipose/50% glandular composition, from 12% for 2 cm thick breasts up to 57% for 8 cm thick breasts.

  14. A technique optimization protocol and the potential for dose reduction in digital mammography

    PubMed Central

    Ranger, Nicole T.; Lo, Joseph Y.; Samei, Ehsan

    2010-01-01

    Digital mammography requires revisiting techniques that have been optimized for prior screen∕film mammography systems. The objective of the study was to determine optimized radiographic technique for a digital mammography system and demonstrate the potential for dose reduction in comparison to the clinically established techniques based on screen- film. An objective figure of merit (FOM) was employed to evaluate a direct-conversion amorphous selenium (a-Se) FFDM system (Siemens Mammomat NovationDR, Siemens AG Medical Solutions, Erlangen, Germany) and was derived from the quotient of the squared signal-difference-to-noise ratio to mean glandular dose, for various combinations of technique factors and breast phantom configurations including kilovoltage settings (23–35 kVp), target∕filter combinations (Mo–Mo and W–Rh), breast-equivalent plastic in various thicknesses (2–8 cm) and densities (100% adipose, 50% adipose∕50% glandular, and 100% glandular), and simulated mass and calcification lesions. When using a W–Rh spectrum, the optimized FOM results for the simulated mass and calcification lesions showed highly consistent trends with kVp for each combination of breast density and thickness. The optimized kVp ranged from 26 kVp for 2 cm 100% adipose breasts to 30 kVp for 8 cm 100% glandular breasts. The use of the optimized W–Rh technique compared to standard Mo–Mo techniques provided dose savings ranging from 9% for 2 cm thick, 100% adipose breasts, to 63% for 6 cm thick, 100% glandular breasts, and for breasts with a 50% adipose∕50% glandular composition, from 12% for 2 cm thick breasts up to 57% for 8 cm thick breasts. PMID:20384232

  15. Expert system and process optimization techniques for real-time monitoring and control of plasma processes

    NASA Astrophysics Data System (ADS)

    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).

  16. Comparative Studies of Particle Swarm Optimization Techniques for Reactive Power Allocation Planning in Power Systems

    NASA Astrophysics Data System (ADS)

    Fukuyama, Yoshikazu

    This paper compares particle swarm optimization (PSO) techniques for a reactive power allocation planning problem in power systems. The problem can be formulated as a mixed-integer nonlinear optimization problem (MINLP). The PSO based methods determines a reactive power allocation strategy with continuous and discrete state variables such as automatic voltage regulator (AVR) operating values of electric power generators, tap positions of on-load tap changer (OLTC) of transformers, and the number of reactive power compensation equipment. Namely, this paper investigates applicability of PSO techniques to one of the practical MINLPs in power systems. Four variations of PSO: PSO with inertia weight approach (IWA), PSO with constriction factor approach (CFA), hybrid particle swarm optimization (HPSO) with IWA, and HPSO with CFA are compared. The four methods are applied to the standard IEEE14 bus system and a practical 112 bus system.

  17. Neural network and polynomial-based response surface techniques for supersonic turbine design optimization

    NASA Astrophysics Data System (ADS)

    Papila, Nilay Uzgoren

    Turbine performance directly affects engine specific impulse, thrust-to-weight ratio, and cost in a rocket propulsion system. This dissertation focuses on methodology and application of employing optimization techniques, with the neural network (NN) and polynomial-based response surface method (RSM), for supersonic turbine optimization. The research is relevant to NASA's reusable launching vehicle initiatives. It is demonstrated that accuracy of the response surface (RS) approximations can be improved with combined utilization of the NN and polynomial techniques, and higher emphases on data in regions of interests. The design of experiment methodology is critical while performing optimization in efficient and effective manners. In physical applications, both preliminary design and detailed shape design optimization are investigated. For preliminary design level, single-, two-, and three-stage turbines are considered with the number of design variables increasing from six to 11 and then to 15, in accordance with the number of stages. A major goal of the preliminary optimization effort is to balance the desire of maximizing aerodynamic performance and minimizing weight. To ascertain required predictive capability of the RSM, a two-level domain refinement approach (windowing) has been adopted. The accuracy of the predicted optimal design points based on this strategy is shown to be satisfactory. The results indicate that the two-stage turbine is the optimum configuration with the higher efficiency corresponding to smaller weights. It is demonstrated that the criteria for selecting the database exhibit significant impact on the efficiency and effectiveness of the construction of the response surface. Based on the optimized preliminary design outcome, shape optimization is performed for vanes and blades of a two-stage supersonic turbine, involving O(10) design variables. It is demonstrated that a major merit of the RS-based optimization approach is that it enables one

  18. Probability-based least square support vector regression metamodeling technique for crashworthiness optimization problems

    NASA Astrophysics Data System (ADS)

    Wang, Hu; Li, Enying; Li, G. Y.

    2011-03-01

    This paper presents a crashworthiness design optimization method based on a metamodeling technique. The crashworthiness optimization is a highly nonlinear and large scale problem, which is composed various nonlinearities, such as geometry, material and contact and needs a large number expensive evaluations. In order to obtain a robust approximation efficiently, a probability-based least square support vector regression is suggested to construct metamodels by considering structure risk minimization. Further, to save the computational cost, an intelligent sampling strategy is applied to generate sample points at the stage of design of experiment (DOE). In this paper, a cylinder, a full vehicle frontal collision is involved. The results demonstrate that the proposed metamodel-based optimization is efficient and effective in solving crashworthiness, design optimization problems.

  19. Identification of a reflection boundary coefficient in an acoustic wave equation by optimal control techniques

    SciTech Connect

    Lenhart, S. |; Protopopescu, V.; Yong, J.

    1997-12-31

    The authors apply optimal control techniques to find approximate solutions to an inverse problem for the acoustic wave equation. The inverse problem (assumed here to have a solution) is to determine the boundary reflection coefficient from partial measurements of the acoustic signal. The sought reflection coefficient is treated as a control and the goal--quantified by an approximate functional--is to drive the model solution close to the experimental data by adjusting this coefficient. The problem is solved by finding the optimal control that minimizes the approximate functional. Then by driving the cost of the control to zero one proves that the corresponding sequence of optimal controls represents a converging sequence of estimates for the solution of the inverse problem. Compared to classical regularization methods (e.g., Tikhonov coupled with optimization schemes), their approach yields: (1) a systematic procedure to solve inverse problems of identification type and (ii) an explicit expression for the approximations of the solution.

  20. Techniques for optimal crop selection in a controlled ecological life support system

    NASA Technical Reports Server (NTRS)

    Mccormack, Ann; Finn, Cory; Dunsky, Betsy

    1993-01-01

    A Controlled Ecological Life Support System (CELSS) utilizes a plant's natural ability to regenerate air and water while being grown as a food source in a closed life support system. Current plant research is directed toward obtaining quantitative empirical data on the regenerative ability of each species of plant and the system volume and power requirements. Two techniques were adapted to optimize crop species selection while at the same time minimizing the system volume and power requirements. Each allows the level of life support supplied by the plants to be selected, as well as other system parameters. The first technique uses decision analysis in the form of a spreadsheet. The second method, which is used as a comparison with and validation of the first, utilizes standard design optimization techniques. Simple models of plant processes are used in the development of these methods.

  1. Techniques for optimal crop selection in a controlled ecological life support system

    NASA Technical Reports Server (NTRS)

    Mccormack, Ann; Finn, Cory; Dunsky, Betsy

    1992-01-01

    A Controlled Ecological Life Support System (CELSS) utilizes a plant's natural ability to regenerate air and water while being grown as a food source in a closed life support system. Current plant research is directed toward obtaining quantitative empirical data on the regenerative ability of each species of plant and the system volume and power requirements. Two techniques were adapted to optimize crop species selection while at the same time minimizing the system volume and power requirements. Each allows the level of life support supplied by the plants to be selected, as well as other system parameters. The first technique uses decision analysis in the form of a spreadsheet. The second method, which is used as a comparison with and validation of the first, utilizes standard design optimization techniques. Simple models of plant processes are used in the development of these methods.

  2. A Comparative Study of Clear Corneal Phacoemulsification with Rigid IOL Versus SICS; the Preferred Surgical Technique in Low Socio-economic group Patients of Rural Areas

    PubMed Central

    Agarwal, Smita; Singh, Pankaj Kumar

    2014-01-01

    Context: Low socio-economic group patients from rural areas often opt for free cataract surgeries offered by charitable organisations. SICS continues to be a time tested technique for cataract removal in such patients. In recent times, camp patients are sometimes treated by clear corneal phacoemulsification with implantation of a rigid IOL, which being more cost effective is often provided for camp patients. This study was undertaken to find out which surgical technique yielded better outcomes and was more suited for high volume camp surgery. Aim: To find the better surgical option- phacoemulsification with rigid IOL or SICS, in poor patients from rural areas. Settings and Design: A prospective randomised controlled trial of cataract patients operated by two different techniques. Materials and Methods: One hundred and twelve eyes were selected and were randomly allocated into two groups of 56 eyes each. At completion of the study, data was analysed for 52 eyes operated by clear corneal phacoemulsification and implantation of a rigid IOL, and 56 eyes operated by SICS. Statistical Analysis Used: Unpaired t-test was used to calculate the p- value. Results: The results were evaluated on the following criteria. The mean post-operative astigmatism at the end of four weeks - was significantly higher in phacoemulsification group as compared to SICS group The BCVA (best corrected visual acuity) at the end of four weeks - was comparable in both groups. Subjective complaints and/ or complications: In phaco group two patients required sutures and seven had striate keratitis , while none in SICS group. Complaint of irritation was similar in both groups. Surgical time- was less for SICS group as compared to phaco group. Conclusion: SICS by virtue of being a faster surgery with more secure wound and significantly less astigmatism is a better option in camp patients from rural areas as compared to phacoemulsification with rigid IOL. PMID:25584291

  3. New surgical techniques and surgical site infections.

    PubMed Central

    Gordon, S. M.

    2001-01-01

    Technologic advances in surgery include a trend toward less invasive procedures, driven by potential benefits to patients and by health-care economics. These less invasive procedures provide infection control personnel opportunities for direct involvement in outcomes measurement. PMID:11294710

  4. Minimally invasive surgical training: challenges and solutions.

    PubMed

    Pierorazio, Phillip M; Allaf, Mohamad E

    2009-01-01

    Treatment options for urological malignancies continue to increase and include endoscopic, laparoscopic, robotic, and image-guided percutaneous techniques. This ever expanding array of technically demanding management options coupled with a static training paradigm introduces challenges to training the urological oncologist of the future. Minimally invasive learning opportunities continue to evolve, and include an intensive experience during residency, postgraduate short courses or mini-apprenticeships, and full time fellowship programs. Incorporation of large animal surgery and surgical simulators may help shorten the necessary learning curve. Ultimately, programs must provide an intense hands-on experience to trainees in all minimally invasive surgical aspects for optimal training. PMID:19285236

  5. Evolutionary techniques for sensor networks energy optimization in marine environmental monitoring

    NASA Astrophysics Data System (ADS)

    Grimaccia, Francesco; Johnstone, Ron; Mussetta, Marco; Pirisi, Andrea; Zich, Riccardo E.

    2012-10-01

    The sustainable management of coastal and offshore ecosystems, such as for example coral reef environments, requires the collection of accurate data across various temporal and spatial scales. Accordingly, monitoring systems are seen as central tools for ecosystem-based environmental management, helping on one hand to accurately describe the water column and substrate biophysical properties, and on the other hand to correctly steer sustainability policies by providing timely and useful information to decision-makers. A robust and intelligent sensor network that can adjust and be adapted to different and changing environmental or management demands would revolutionize our capacity to wove accurately model, predict, and manage human impacts on our coastal, marine, and other similar environments. In this paper advanced evolutionary techniques are applied to optimize the design of an innovative energy harvesting device for marine applications. The authors implement an enhanced technique in order to exploit in the most effective way the uniqueness and peculiarities of two classical optimization approaches, Particle Swarm Optimization and Genetic Algorithms. Here, this hybrid procedure is applied to a power buoy designed for marine environmental monitoring applications in order to optimize the recovered energy from sea-wave, by selecting the optimal device configuration.

  6. Evaluation of surgical impaction technique and how it affects locking strength of the head-stem taper junction.

    PubMed

    Scholl, Laura; Schmidig, Gregg; Faizan, Ahmad; TenHuisen, Kevor; Nevelos, Jim

    2016-07-01

    Cases of fretting and corrosion at the taper junction have been reported in large metal-on-metal bearing combinations, and more recently, this concern has included metal-on-polyethylene bearing combinations. Many of these patients have been revised due to adverse local tissue reaction secondary to taper corrosion. This taper corrosion-related adverse local tissue reaction seems to be a multifactorial issue and difficult to assess. The aim of this study was to look at one potential variable, the impaction behavior (impaction force, number of blows, etc.) of orthopedic surgeons, and understand how this can affect the locking strength of tapers. A group of experienced orthopedic surgeons were asked to use their typical surgical approach to impact a femoral head onto a hip femoral stem using an Operating Room (OR)-simulated test setup. Impaction parameters such as impaction force, velocity, and energy, as well as the number of impacts, were characterized and applied in a bench-top study used to evaluate the effect of these parameters on the initial stability of the taper junction. High variation was found in the surgical impaction parameters, but overall it was determined that increased impaction force correlated to superior stability of the taper junction. PMID:27107031

  7. Optimization technique for improved microwave transmission from multi-solar power satellites

    NASA Technical Reports Server (NTRS)

    Arndt, G. D.; Kerwin, E. M.

    1982-01-01

    An optimization technique for generating antenna illumination tapers allows improved microwave transmission efficiencies from proposed solar power satellite (SPS) systems and minimizes sidelobe levels to meet preset environmental standards. The cumulative microwave power density levels from 50 optimized SPS systems are calculated at the centroids of each of the 3073 counties in the continental United States. These cumulative levels are compared with Environmental Protection Agency (EPA) measured levels of electromagnetic radiation in seven eastern cities. Effects of rectenna relocations upon the power levels/population exposure rates are also studied.

  8. Optimization technique for improved microwave transmission from multi-solar power satellites

    SciTech Connect

    Arndt, G.D.; Kerwin, E.M.

    1982-08-01

    An optimization technique for generating antenna illumination tapers allows improved microwave transmission efficiencies from proposed solar power satellite (SPS) systems and minimizes sidelobe levels to meet preset environmental standards. The cumulative microwave power density levels from 50 optimized SPS systems are calculated at the centroids of each of the 3073 counties in the continental United States. These cumulative levels are compared with Environmental Protection Agency (EPA) measured levels of electromagnetic radiation in seven eastern cities. Effects of rectenna relocations upon the power levels/population exposure rates are also studied.

  9. Efficient Fast Stereo Acoustic Echo Cancellation Based on Pairwise Optimal Weight Realization Technique

    NASA Astrophysics Data System (ADS)

    Yukawa, Masahiro; Murakoshi, Noriaki; Yamada, Isao

    2006-12-01

    In stereophonic acoustic echo cancellation (SAEC) problem, fast and accurate tracking of echo path is strongly required for stable echo cancellation. In this paper, we propose a class of efficient fast SAEC schemes with linear computational complexity (with respect to filter length). The proposed schemes are based on pairwise optimal weight realization (POWER) technique, thus realizing a "best" strategy (in the sense of pairwise and worst-case optimization) to use multiple-state information obtained by preprocessing. Numerical examples demonstrate that the proposed schemes significantly improve the convergence behavior compared with conventional methods in terms of system mismatch as well as echo return loss enhancement (ERLE).

  10. Comparison of Two Spatial Optimization Techniques: A Framework to Solve Multiobjective Land Use Distribution Problems

    NASA Astrophysics Data System (ADS)

    Meyer, Burghard Christian; Lescot, Jean-Marie; Laplana, Ramon

    2009-02-01

    Two spatial optimization approaches, developed from the opposing perspectives of ecological economics and landscape planning and aimed at the definition of new distributions of farming systems and of land use elements, are compared and integrated into a general framework. The first approach, applied to a small river catchment in southwestern France, uses SWAT (Soil and Water Assessment Tool) and a weighted goal programming model in combination with a geographical information system (GIS) for the determination of optimal farming system patterns, based on selected objective functions to minimize deviations from the goals of reducing nitrogen and maintaining income. The second approach, demonstrated in a suburban landscape near Leipzig, Germany, defines a GIS-based predictive habitat model for the search of unfragmented regions suitable for hare populations ( Lepus europaeus), followed by compromise optimization with the aim of planning a new habitat structure distribution for the hare. The multifunctional problem is solved by the integration of the three landscape functions (“production of cereals,” “resistance to soil erosion by water,” and “landscape water retention”). Through the comparison, we propose a framework for the definition of optimal land use patterns based on optimization techniques. The framework includes the main aspects to solve land use distribution problems with the aim of finding the optimal or best land use decisions. It integrates indicators, goals of spatial developments and stakeholders, including weighting, and model tools for the prediction of objective functions and risk assessments. Methodological limits of the uncertainty of data and model outcomes are stressed. The framework clarifies the use of optimization techniques in spatial planning.

  11. Talus fractures: surgical principles.

    PubMed

    Rush, Shannon M; Jennings, Meagan; Hamilton, Graham A

    2009-01-01

    Surgical treatment of talus fractures can challenge even the most skilled foot and ankle surgeon. Complicated fracture patterns combined with joint dislocation of variable degrees require accurate assessment, sound understanding of principles of fracture care, and broad command of internal fixation techniques needed for successful surgical care. Elimination of unnecessary soft tissue dissection, a low threshold for surgical reduction, liberal use of malleolar osteotomy to expose body fracture, and detailed attention to fracture reduction and joint alignment are critical to the success of treatment. Even with the best surgical care complications are common and seem to correlate with injury severity and open injuries. PMID:19121756

  12. Solid oxide fuel cell simulation and design optimization with numerical adjoint techniques

    NASA Astrophysics Data System (ADS)

    Elliott, Louie C.

    This dissertation reports on the application of numerical optimization techniques as applied to fuel cell simulation and design. Due to the "multi-physics" inherent in a fuel cell, which results in a highly coupled and non-linear behavior, an experimental program to analyze and improve the performance of fuel cells is extremely difficult. This program applies new optimization techniques with computational methods from the field of aerospace engineering to the fuel cell design problem. After an overview of fuel cell history, importance, and classification, a mathematical model of solid oxide fuel cells (SOFC) is presented. The governing equations are discretized and solved with computational fluid dynamics (CFD) techniques including unstructured meshes, non-linear solution methods, numerical derivatives with complex variables, and sensitivity analysis with adjoint methods. Following the validation of the fuel cell model in 2-D and 3-D, the results of the sensitivity analysis are presented. The sensitivity derivative for a cost function with respect to a design variable is found with three increasingly sophisticated techniques: finite difference, direct differentiation, and adjoint. A design cycle is performed using a simple optimization method to improve the value of the implemented cost function. The results from this program could improve fuel cell performance and lessen the world's dependence on fossil fuels.

  13. Influence of robust optimization in intensity-modulated proton therapy with different dose delivery techniques

    SciTech Connect

    Liu Wei; Li Yupeng; Li Xiaoqiang; Cao Wenhua; Zhang Xiaodong

    2012-06-15

    Purpose: The distal edge tracking (DET) technique in intensity-modulated proton therapy (IMPT) allows for high energy efficiency, fast and simple delivery, and simple inverse treatment planning; however, it is highly sensitive to uncertainties. In this study, the authors explored the application of DET in IMPT (IMPT-DET) and conducted robust optimization of IMPT-DET to see if the planning technique's sensitivity to uncertainties was reduced. They also compared conventional and robust optimization of IMPT-DET with three-dimensional IMPT (IMPT-3D) to gain understanding about how plan robustness is achieved. Methods: They compared the robustness of IMPT-DET and IMPT-3D plans to uncertainties by analyzing plans created for a typical prostate cancer case and a base of skull (BOS) cancer case (using data for patients who had undergone proton therapy at our institution). Spots with the highest and second highest energy layers were chosen so that the Bragg peak would be at the distal edge of the targets in IMPT-DET using 36 equally spaced angle beams; in IMPT-3D, 3 beams with angles chosen by a beam angle optimization algorithm were planned. Dose contributions for a number of range and setup uncertainties were calculated, and a worst-case robust optimization was performed. A robust quantification technique was used to evaluate the plans' sensitivity to uncertainties. Results: With no uncertainties considered, the DET is less robust to uncertainties than is the 3D method but offers better normal tissue protection. With robust optimization to account for range and setup uncertainties, robust optimization can improve the robustness of IMPT plans to uncertainties; however, our findings show the extent of improvement varies. Conclusions: IMPT's sensitivity to uncertainties can be improved by using robust optimization. They found two possible mechanisms that made improvements possible: (1) a localized single-field uniform dose distribution (LSFUD) mechanism, in which the

  14. Successful surgical treatment for total circumferential aortic and mitral annulus calcification: application of half-and-half technique.

    PubMed

    Takahashi, Yosuke; Sasaki, Yasuyuki; Hattori, Koji; Kato, Yasuyuki; Motoki, Manabu; Morisaki, Akimasa; Nishimura, Shinsuke; Shibata, Toshihiko

    2016-07-01

    Patients with total circumferential mitral annular calcification (MAC) extending into the intervalvular fibrous body and aortic annulus have a high risk of cardiac surgery, which remains a technical challenge for surgeons. Our technique for MAC is characterized as simple supra-mitral annular prosthesis insertion after minimum debridement of calcification ("half-and-half technique"). To date, our technique has been applied in only simple MAC cases and has good results. Herein, we report successful two cases of total circumferential MAC, extending into the intervalvular fibrous body and aortic annulus that were treated by a simple double valve replacement with application of our "half-and-half technique". PMID:25385543

  15. Enterocutaneous Fistula: Different Surgical Intervention Techniques for Closure along with Comparative Evaluation of Aluminum Paint, Karaya Gum (Hollister) and Gum Acacia for Peristomal Skin Care

    PubMed Central

    Namrata; Ahmad, Shabi

    2015-01-01

    Introduction Gastrointestinal fistulas are serious complications and are associated with high morbidity and mortality rates. In majority of the patients, fistulas are treatable. However, the treatment is very complex and often multiple therapies are required. These highly beneficial treatment options which could shorten fistula closure time also result in considerable hospital cost savings. Aim This study was planned to study aetiology, clinical presentation, morbidity and mortality of enterocutaneous fistula and to evaluate the different surgical intervention techniques for closure of enterocutaneous fistula along with a comparative evaluation of different techniques for management of peristomal skin with special emphasis on aluminum paint, Karaya gum (Hollister) and Gum Acacia. Materials and Methods This prospective observational study was conducted in the Department of Surgery, M.L.N. Medical College, Allahabad and its associated hospital (S.R.N. Hospital, Allahabad) for a period of five years. Results Majority of enterocutaneous fistula were of small bowel and medium output fistulas (500-1000 ml/24hours). Most of the patients were treated with conservative treatment as compared to surgical intervention. Large bowel fistula has maximum spontaneous closure rate compare to small bowel and duodenum. Number of orifice whether single or multiple does not appear to play statistically significant role in spontaneous closure of fistula. Serum Albumin is a significantly important predictor of spontaneous fistula closure and mortality. Surgical management appeared to be the treatment of choice in distal bowel fistula. The application of karaya gum (Hollister kit), Gum Acacia and Aluminum Paint gave similar outcome. Conclusion Postoperative fistulas are the most common aetiology of enterocutaneous fistula and various factors do play role in management. Peristomal skin care done with Karaya Gum, Gum Acacia and Aluminum Paint has almost equal efficiency in management of skin

  16. Biocompatibility of surgical implants

    NASA Technical Reports Server (NTRS)

    Kaelble, D. H.

    1979-01-01

    Method of selecting biocompatible materials for surgical implants uses fracture mechanic relationships and surface energies of candidate materials in presence of blood plasma. Technique has been used to characterize 190 materials by parameters that reflect their biocompatibility.

  17. Optimization of brushless direct current motor design using an intelligent technique.

    PubMed

    Shabanian, Alireza; Tousiwas, Armin Amini Poustchi; Pourmandi, Massoud; Khormali, Aminollah; Ataei, Abdolhay

    2015-07-01

    This paper presents a method for the optimal design of a slotless permanent magnet brushless DC (BLDC) motor with surface mounted magnets using an improved bee algorithm (IBA). The characteristics of the motor are expressed as functions of motor geometries. The objective function is a combination of losses, volume and cost to be minimized simultaneously. This method is based on the capability of swarm-based algorithms in finding the optimal solution. One sample case is used to illustrate the performance of the design approach and optimization technique. The IBA has a better performance and speed of convergence compared with bee algorithm (BA). Simulation results show that the proposed method has a very high/efficient performance. PMID:25841938

  18. Retrograde Approach Using Surgical Cutdown Technique for Limb Salvage in a Case of Critical Limb Ischemia With Severely Calcified Tibial Occlusive Disease.

    PubMed

    Shiraki, Tatsuya; Iida, Osamu; Suemitsu, Kotaro; Tsuji, Yoriko; Uematsu, Masaaki

    2016-05-01

    We here report a successful angioplasty for tibial artery occlusion using direct tibial puncture and subsequent retrograde approach under surgical cutdown technique. An 82-year-old man with ulcer/gangrene in first and second digits was referred to our hospital for endovascular therapy (EVT) of lower extremity ischemia. Diagnostic angiogram revealed anterior tibial artery (ATA) occlusion with severe calcification. Subintimal angioplasty was attempted using a 0.014-inch hydrophilic guidewire but was unsuccessful. A retrograde approach was subsequently attempted for ATA recanalization. However, because of severe calcification of dorsal pedis artery (DPA), percutaneous distal puncture was also unsuccessful. Direct puncture under surgical cutdown technique for DPA was subsequently performed and was successful. A 0.014-inch hydrophilic wire was advanced in retrograde fashion across the ATA occlusion and was used to access the microcatheter positioned at the proximal ATA via antegrade approach. Angioplasty of the ATA occlusion was performed using a 2.5-/3.0-mm tapered balloon. Completion angiogram revealed restoration of flow without dissection. Skin perfusion pressure was dramatically improved. Complete wound healing was achieved 5 months after EVT. PMID:27207678

  19. Maintaining Optimal Surgical Conditions With Low Insufflation Pressures is Possible With Deep Neuromuscular Blockade During Laparoscopic Colorectal Surgery

    PubMed Central

    Kim, Myoung Hwa; Lee, Ki Young; Lee, Kang-Young; Min, Byung-Soh; Yoo, Young Chul

    2016-01-01

    Abstract Carbon dioxide (CO2) absorption and increased intra-abdominal pressure can adversely affect perioperative physiology and postoperative recovery. Deep muscle relaxation is known to improve the surgical conditions during laparoscopic surgery. We aimed to compare the effects of deep and moderate neuromuscular block in laparoscopic colorectal surgery, including intra-abdominal pressure. In this prospective, double-blind, parallel-group trial, 72 adult patients undergoing laparoscopic colorectal surgery were randomized using an online randomization generator to achieve either moderate (1–2 train-of-four response, n = 36) or deep (1–2 post-tetanic count, n = 36) neuromuscular block by receiving a continuous infusion of rocuronium. Adjusted intra-abdominal pressure, which was titrated by a surgeon with maintaining the operative field during pneumoperitoneum, was recorded at 5-minute intervals. Perioperative hemodynamic parameters and postoperative outcomes were assessed. Six patients from the deep and 5 from the moderate neuromuscular block group were excluded, leaving 61 for analysis. The average adjusted IAP was lower in the deep compared to the moderate neuromuscular block group (9.3 vs 12 mm Hg, P < 0.001). The postoperative pain scores (P < 0.001) and incidence of postoperative shoulder tip pain were lower, whereas gas passing time (P = 0.002) and sips of water time (P = 0.005) were shorter in the deep neuromuscular block than in the moderate neuromuscular block group. Deep neuromuscular blocking showed several benefits compared to conventional moderate neuromuscular block, including a greater intra-abdominal pressure lowering effect, whereas surgical conditions are maintained, less severe postoperative pain and faster bowel function recovery. PMID:26945393

  20. Eversion-Inversion Labral Repair and Reconstruction Technique for Optimal Suction Seal

    PubMed Central

    Moreira, Brett; Pascual-Garrido, Cecilia; Chadayamurri, Vivek; Mei-Dan, Omer

    2015-01-01

    Labral tears are a significant cause of hip pain and are currently the most common indication for hip arthroscopy. Compared with labral debridement, labral repair has significantly better outcomes in terms of both daily activities and athletic pursuits in the setting of femoral acetabular impingement. The classic techniques described in the literature for labral repair all use loop or pass-through intrasubstance labral sutures to achieve a functional hip seal. This hip seal is important for hip stability and optimal joint biomechanics, as well as in the prevention of long-term osteoarthritis. We describe a novel eversion-inversion intrasubstance suturing technique for labral repair and reconstruction that can assist in restoration of the native labrum position by re-creating an optimal seal around the femoral head. PMID:26870648

  1. An Optimized Integrator Windup Protection Technique Applied to a Turbofan Engine Control

    NASA Technical Reports Server (NTRS)

    Watts, Stephen R.; Garg, Sanjay

    1995-01-01

    This paper introduces a new technique for providing memoryless integrator windup protection which utilizes readily available optimization software tools. This integrator windup protection synthesis provides a concise methodology for creating integrator windup protection for each actuation system loop independently while assuring both controller and closed loop system stability. The individual actuation system loops' integrator windup protection can then be combined to provide integrator windup protection for the entire system. This technique is applied to an H(exp infinity) based multivariable control designed for a linear model of an advanced afterburning turbofan engine. The resulting transient characteristics are examined for the integrated system while encountering single and multiple actuation limits.

  2. Parametric Studies and Optimization of Eddy Current Techniques through Computer Modeling

    SciTech Connect

    Todorov, E. I.

    2007-03-21

    The paper demonstrates the use of computer models for parametric studies and optimization of surface and subsurface eddy current techniques. The study with high-frequency probe investigates the effect of eddy current frequency and probe shape on the detectability of flaws in the steel substrate. The low-frequency sliding probe study addresses the effect of conductivity between the fastener and the hole, frequency and coil separation distance on detectability of flaws in subsurface layers.

  3. Method and apparatus for optimizing operation of a power generating plant using artificial intelligence techniques

    SciTech Connect

    Wroblewski, David; Katrompas, Alexander M.; Parikh, Neel J.

    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.

  4. Influence of robust optimization in intensity-modulated proton therapy with different dose delivery techniques

    PubMed Central

    Liu, Wei; Li, Yupeng; Li, Xiaoqiang; Cao, Wenhua; Zhang, Xiaodong

    2012-01-01

    Purpose: The distal edge tracking (DET) technique in intensity-modulated proton therapy (IMPT) allows for high energy efficiency, fast and simple delivery, and simple inverse treatment planning; however, it is highly sensitive to uncertainties. In this study, the authors explored the application of DET in IMPT (IMPT-DET) and conducted robust optimization of IMPT-DET to see if the planning technique’s sensitivity to uncertainties was reduced. They also compared conventional and robust optimization of IMPT-DET with three-dimensional IMPT (IMPT-3D) to gain understanding about how plan robustness is achieved. Methods: They compared the robustness of IMPT-DET and IMPT-3D plans to uncertainties by analyzing plans created for a typical prostate cancer case and a base of skull (BOS) cancer case (using data for patients who had undergone proton therapy at our institution). Spots with the highest and second highest energy layers were chosen so that the Bragg peak would be at the distal edge of the targets in IMPT-DET using 36 equally spaced angle beams; in IMPT-3D, 3 beams with angles chosen by a beam angle optimization algorithm were planned. Dose contributions for a number of range and setup uncertainties were calculated, and a worst-case robust optimization was performed. A robust quantification technique was used to evaluate the plans’ sensitivity to uncertainties. Results: With no uncertainties considered, the DET is less robust to uncertainties than is the 3D method but offers better normal tissue protection. With robust optimization to account for range and setup uncertainties, robust optimization can improve the robustness of IMPT plans to uncertainties; however, our findings show the extent of improvement varies. Conclusions: IMPT’s sensitivity to uncertainties can be improved by using robust optimization. They found two possible mechanisms that made improvements possible: (1) a localized single-field uniform dose distribution (LSFUD) mechanism, in which the

  5. Endonasal endoscopic dacryocystorhinostomy: how to achieve optimal results with simple punch technique.

    PubMed

    Naraghi, Mohsen; Tabatabaii Mohammadi, Sayed Ziaeddin; Sontou, Alain Fabrice; Farajzadeh Deroee, Armin; Boroojerdi, Masoud

    2012-05-01

    Endonasal endoscopic dacryocystorhinostomy (EEDCR) has been popularized as a minimally invasive technique. Although preliminary reports revealed less success in comparison with external approaches, recent endonasal endoscopic surgeries on various types of DCR have preserved advantages of this technique while diminishing the failures. We described our experience on EEDCR, including the main advantages and disadvantages of it. Hundred consecutive cases of lachrymal problems underwent EEDCR utilizing simple punch removal of bone, instead of powered instrumentation or lasers. The medial aspect of the sac was removed in all of patients, while preserving normal mucosa around the sac. Hundred cases of EEDCR were performed on 81 patients, with 19 bilateral procedures. Nine procedures were performed under local anesthesia. Based on a mean 14 months follow-up, 95 cases were free of symptoms, revealing 95% success rate. The punch technique diminishes the expenses of powered or laser instrumentation with comparable results. It seems that preserving normal tissues and creating a patent rhinostomy with least surgical trauma and less subsequent scar, plays the most important role in achieving desirable results. PMID:22065173

  6. Does the piezoelectric surgical technique produce fewer postoperative sequelae after lower third molar surgery than conventional rotary instruments? A systematic review and meta analysis.

    PubMed

    Al-Moraissi, E A; Elmansi, Y A; Al-Sharaee, Y A; Alrmali, A E; Alkhutari, A S

    2016-03-01

    A systematic review and meta-analysis was conducted to answer the clinical question "Does the piezoelectric surgical technique produce fewer postoperative sequelae after lower third molar surgery than conventional rotary instruments?" A systematic and electronic search of several databases with specific key words, a reference search, and a manual search were performed from respective dates of inception through November 2014. The inclusion criteria were clinical human studies, including randomized controlled trials (RCTs), controlled clinical trials (CCTs), and retrospective studies, with the aim of comparing the piezoelectric surgical osteotomy technique to the standard rotary instrument technique in lower third molar surgery. Postoperative sequelae (oedema, trismus, and pain), the total number of analgesics taken, and the duration of surgery were analyzed. A total of nine articles were included, six RCTs, two CCTs, and one retrospective study. Six studies had a low risk of bias and three had a moderate risk of bias. A statistically significant difference was found between piezoelectric surgery and conventional rotary instrument surgery for lower third molar extraction with regard to postoperative sequelae (oedema, trismus, and pain) and the total number of analgesics taken (P=0.0001, P=0.0001, P<0.00001, and P<0.0001, respectively). However, a statistically significant increased surgery time was required in the piezoelectric osteotomy group (P<0.00001). The results of the meta-analysis showed that piezoelectric surgery significantly reduced the occurrence of postoperative sequelae (oedema, trismus, and pain) and the total number of analgesics taken compared to the conventional rotary instrument technique in lower third molar surgery, but required a longer surgery time. PMID:26572830

  7. The L_infinity constrained global optimal histogram equalization technique for real time imaging

    NASA Astrophysics Data System (ADS)

    Ren, Qiongwei; Niu, Yi; Liu, Lin; Jiao, Yang; Shi, Guangming

    2015-08-01

    Although the current imaging sensors can achieve 12 or higher precision, the current display devices and the commonly used digital image formats are still only 8 bits. This mismatch causes significant waste of the sensor precision and loss of information when storing and displaying the images. For better usage of the precision-budget, tone mapping operators have to be used to map the high-precision data into low-precision digital images adaptively. In this paper, the classic histogram equalization tone mapping operator is reexamined in the sense of optimization. We point out that the traditional histogram equalization technique and its variants are fundamentally improper by suffering from local optimum problems. To overcome this drawback, we remodel the histogram equalization tone mapping task based on graphic theory which achieves the global optimal solutions. Another advantage of the graphic-based modeling is that the tone-continuity is also modeled as a vital constraint in our approach which suppress the annoying boundary artifacts of the traditional approaches. In addition, we propose a novel dynamic programming technique to solve the histogram equalization problem in real time. Experimental results shows that the proposed tone-preserved global optimal histogram equalization technique outperforms the traditional approaches by exhibiting more subtle details in the foreground while preserving the smoothness of the background.

  8. An Adaptive Image Enhancement Technique by Combining Cuckoo Search and Particle Swarm Optimization Algorithm

    PubMed Central

    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. PMID:25784928

  9. An adaptive image enhancement technique by combining cuckoo search and particle swarm optimization algorithm.

    PubMed

    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. PMID:25784928

  10. Dosimetric characterization and optimization of a customized Stanford total skin electron irradiation (TSEI) technique.

    PubMed

    Luĉić, Felipe; Sánchez-Nieto, Beatriz; Caprile, Paola; Zelada, Gabriel; Goset, Karen

    2013-01-01

    Total skin electron irradiation (TSEI) has been used as a treatment for mycosis fungoides. Our center has implemented a modified Stanford technique with six pairs of 6 MeV adjacent electron beams, incident perpendicularly on the patient who remains lying on a translational platform, at 200 cm from the source. The purpose of this study is to perform a dosimetric characterization of this technique and to investigate its optimization in terms of energy characteristics, extension, and uniformity of the treatment field. In order to improve the homogeneity of the distribution, a custom-made polyester filter of variable thickness and a uniform PMMA degrader plate were used. It was found that the characteristics of a 9 MeV beam with an 8 mm thick degrader were similar to those of the 6 MeV beam without filter, but with an increased surface dose. The combination of the degrader and the polyester filter improved the uniformity of the distribution along the dual field (180cm long), increasing the dose at the borders of field by 43%. The optimum angles for the pair of beams were ± 27°. This configuration avoided displacement of the patient, and reduced the treatment time and the positioning problems related to the abutting superior and inferior fields. Dose distributions in the transversal plane were measured for the six incidences of the Stanford technique with film dosimetry in an anthropomorphic pelvic phantom. This was performed for the optimized treatment and compared with the previously implemented technique. The comparison showed an increased superficial dose and improved uniformity of the 85% isodose curve coverage for the optimized technique. PMID:24036877

  11. Optimized swimmer tracking system by a dynamic fusion of correlation and color histogram techniques

    NASA Astrophysics Data System (ADS)

    Benarab, D.; Napoléon, T.; Alfalou, A.; Verney, A.; Hellard, P.

    2015-12-01

    To design a robust swimmer tracking system, we took into account two well-known tracking techniques: the nonlinear joint transform correlation (NL-JTC) and the color histogram. The two techniques perform comparably well, yet they both have substantial limitations. Interestingly, they also seem to show some complementarity. The correlation technique yields accurate detection but is sensitive to rotation, scale and contour deformation, whereas the color histogram technique is robust for rotation and contour deformation but shows low accuracy and is highly sensitive to luminosity and confusing background colors. These observations suggested the possibility of a dynamic fusion of the correlation plane and the color scores map. Before this fusion, two steps are required. First is the extraction of a sub-plane of correlation that describes the similarity between the reference and target images. This sub-plane has the same size as the color scores map but they have different interval values. Thus, the second step is required which is the normalization of the planes in the same interval so they can be fused. In order to determine the benefits of this fusion technique, first, we tested it on a synthetic image containing different forms with different colors. We thus were able to optimize the correlation plane and color histogram techniques before applying our fusion technique to real videos of swimmers in international competitions. Last, a comparative study of the dynamic fusion technique and the two classical techniques was carried out to demonstrate the efficacy of the proposed technique. The criteria of comparison were the tracking percentage, the peak to correlation energy (PCE), which evaluated the sharpness of the peak (accuracy), and the local standard deviation (Local-STD), which assessed the noise in the planes (robustness).

  12. Assessment of the influence of surgical technique on postoperative pain and wound tenderness in cats following ovariohysterectomy.

    PubMed

    Grint, Nicola J; Murison, Pamela J; Coe, Richard J; Waterman Pearson, Avril E

    2006-02-01

    Elective ovariohysterectomy was performed on 66 cats. Surgical approach was flank (group F) or midline (group M) allocated by block randomisation. Pre-anaesthetic medication was acepromazine (0.1 mg/kg) via intramuscular injection. Anaesthesia was induced with intravenous thiopentone, and maintained with halothane in 100% oxygen. Carprofen (4 mg/kg) was administered by the subcutaneous route immediately after induction of anaesthesia. Postoperative pain and wound tenderness were assessed at 1, 3, 6, 9, 11-12 and 20-24h after the end of surgery, and the assessment outcome marked on visual analogue scales (VAS). Intervention analgesia (if pain VAS was >40 mm) was pethidine 4 mg/kg via intramuscular injection. Area under the curve (AUC) for VAS for pain and VAS for wound tenderness for each cat were calculated. AUC for wound tenderness was significantly greater for group F (P = 0.007). There was no significant difference for AUC for pain between the groups. In conclusion, wounds after flank ovariohysterectomy are significantly more tender than after midline ovariohysterectomy in the cat. This indicates that interactive methods, including wound palpation, must be used to assess postoperative pain and the findings should be appropriately weighted in the overall assessment. PMID:16213762

  13. Central pancreatectomy: the Dagradi Serio Iacono operation. Evolution of a surgical technique from the pioneers to the robotic approach.

    PubMed

    Iacono, Calogero; Ruzzenente, Andrea; Bortolasi, Luca; Guglielmi, Alfredo

    2014-11-14

    Central pancreatectomy (CP) is a parenchyma-sparing surgical procedure. The aims are to clarify the history and the development of CP and to give credits to those from whom it came. Ehrhardt, in 1908, described segmental neck resection (SNR) followed, in 1910, by Finney without reconstructive part. In 1950 Honjyo described two cases of SNR combined with gastrectomy for gastric cancer infiltrating the neck of the pancreas. Guillemin and Bessot (1957) and Letton and Wilson (1959) dealt only with the reconstructive aspect of CP. Dagradi and Serio, in 1982, performed the first CP including the resective and reconstructive aspects. Subsequently Iacono has validated it with functional endocrine and exocrine tests and popularized it worldwide. In 2003, Baca and Bokan performed laparoscopic CP and, In 2004, Giulianotti et al performed a robotic assisted CP. CP is performed worldwide either by open surgery or by using minimally-invasive or robotic approaches. This confirms that the operation does not belong to whom introduced it but to everyone who carries out it; however credit must be given to those from whom it came. PMID:25400451

  14. Central pancreatectomy: The Dagradi Serio Iacono operation. Evolution of a surgical technique from the pioneers to the robotic approach

    PubMed Central

    Iacono, Calogero; Ruzzenente, Andrea; Bortolasi, Luca; Guglielmi, Alfredo

    2014-01-01

    Central pancreatectomy (CP) is a parenchyma-sparing surgical procedure. The aims are to clarify the history and the development of CP and to give credits to those from whom it came. Ehrhardt, in 1908, described segmental neck resection (SNR) followed, in 1910, by Finney without reconstructive part. In 1950 Honjyo described two cases of SNR combined with gastrectomy for gastric cancer infiltrating the neck of the pancreas. Guillemin and Bessot (1957) and Letton and Wilson (1959) dealt only with the reconstructive aspect of CP. Dagradi and Serio, in 1982, performed the first CP including the resective and reconstructive aspects. Subsequently Iacono has validated it with functional endocrine and exocrine tests and popularized it worldwide. In 2003, Baca and Bokan performed laparoscopic CP and, In 2004, Giulianotti et al performed a robotic assisted CP. CP is performed worldwide either by open surgery or by using minimally-invasive or robotic approaches. This confirms that the operation does not belong to whom introduced it but to everyone who carries out it; however credit must be given to those from whom it came. PMID:25400451

  15. Determination of the optimal tolerance for MLC positioning in sliding window and VMAT techniques

    SciTech Connect

    Hernandez, V. Abella, R.; Calvo, J. F.; Jurado-Bruggemann, D.; Sancho, I.; Carrasco, P.

    2015-04-15

    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.

  16. Total Pancreatectomy and Islet Auto-Transplantation in Children for Chronic Pancreatitis. Indication, Surgical Techniques, Post Operative Management and Long-Term Outcomes

    PubMed Central

    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.

    2014-01-01

    Objective Describe the surgical technique, complications and long term outcomes of total pancreatectomy and islet auto transplantation (TP-IAT) in a large series of pediatric patients. Summary Background Data 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, while islet auto transplantation (IAT) potentially can prevent or minimize TP-related diabetes. Methods Retrospective review of 75 children undergoing TP-IAT for chronic pancreatitis who had failed medical, endoscopic or surgical treatment between 1989–2012. Results Pancreatitis pain and the severity of pain statistically improved in 90% of patients after TP-IAT (p =<0.001). The relief from narcotics was sustained. Of the 75 patients undergoing TP-IAT, 31 (41.3%) achieved insulin independence. Younger age (p=0.032), lack of prior Puestow (p=0.018), lower body surface area (p=0.048), IEQ per Kg Body Weight (p=0.001) and total IEQ (100,000) (0.004) were associated with insulin independence. By multivariate analysis, 3 factors were associated with insulin independence after TP-IAT:(1) male gender, (2) lower body surface area and the (3) higher total IEQ per kilogram body weight. Total IEQ (100,000) was the single factor most strongly associated with insulin independence (OR = 2.62; p value < 0.001). Conclusions TP-IAT provides sustained pain relief and improved quality of life. The β cell function is dependent on islet yield. TP-IAT is an effective therapy for children with painful pancreatitis that fail medical and or endoscopic management PMID:24509206

  17. Evaluation of Functional Outcomes in Individuals 10 Years after Posterior Lumbar Interbody Fusion with Corundum Implants and Decompression: A Comparison of 2 Surgical Techniques

    PubMed Central

    Truszczyńska, Aleksandra; Rąpała, Kazimierz; Łukawski, Stanislaw; Trzaskoma, Zbigniew; Tarnowski, Adam; Drzal-Grabiec, Justyna; Cabak, Anna

    2014-01-01

    Background The purpose of this study was to evaluate lumbar spine-related functional disability in individuals 10 years after lumbar decompression and lumbar decompression with posterior lumbar interbody fusion (PLIF) with corundum implants surgery for degenerative stenosis and to compare the long-term outcome of these 2 surgical techniques. Material/Methods From 1998 to 2002, 100 patients with single-level lumbar stenosis were surgically treated. The patients were randomly divided into 2 groups that did not differ in terms of clinical or neurological symptoms. Group A consisted of 50 patients who were treated with PLIF and the use of porous ceramic corundum implants; the mean age was 57.74 and BMI was 27.34. Group B consisted of 50 patients treated with decompression by fenestration; mean age was 51.28 and the mean BMI was 28.84. Results There was no statistical significance regarding age, BMI, and sex. Both treatments revealed significant improvements. In group A, ODI decreased from 41.01% to 14.3% at 1 year and 16.3 at 10 years. In group B, ODI decreased from 63.8% to 18.36% at 1 year and 22.36% at 10 years. The difference between groups was statistically significant. There were no differences between the groups regarding the Rolland-Morris disability questionnaire and VAS at 1 and 10 years after surgery. Conclusions Long-term results evaluated according to the ODI, the Rolland-Morris disability questionnaire, and the VAS showed that the both methods significantly reduce patient disability, and this was maintained during next 10 years. The less invasive fenestration procedure was only slightly less favorable than surgical treatment of stenosis by both PLIF with corundum implants and decompression. PMID:25106708

  18. Optimizing charge breeding techniques for ISOL facilities in Europe: Conclusions from the EMILIE project.

    PubMed

    Delahaye, P; Galatà, A; Angot, J; Cam, J F; Traykov, E; Ban, G; Celona, L; Choinski, J; Gmaj, P; Jardin, P; Koivisto, H; Kolhinen, V; Lamy, T; Maunoury, L; Patti, G; Thuillier, T; Tarvainen, O; Vondrasek, R; Wenander, F

    2016-02-01

    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. PMID:26932063

  19. Optimizing charge breeding techniques for ISOL facilities in Europe: Conclusions from the EMILIE project

    NASA Astrophysics Data System (ADS)

    Delahaye, P.; Galatà, A.; Angot, J.; Cam, J. F.; Traykov, E.; Ban, G.; Celona, L.; Choinski, J.; Gmaj, P.; Jardin, P.; Koivisto, H.; Kolhinen, V.; Lamy, T.; Maunoury, L.; Patti, G.; Thuillier, T.; Tarvainen, O.; Vondrasek, R.; Wenander, F.

    2016-02-01

    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.

  20. Temporalis Muscle Transfer for the Treatment of Lagophthalmos in Patients With Leprosy: Refinement in Surgical Techniques to Prevent Postoperative Ptosis.

    PubMed

    Ahn, Sung Yul; Park, Hyang Joon; Kim, Jong Pill; Park, Tae Hwan

    2016-01-01

    Facial paralysis resulting from leprosy has a serious impact on the entire face especially in the areas innervated by the facial nerves. In particular, lagophthalmos in patients with leprosy causes exposure keratitis, corneal, and conjunctival dryness, which can progress to blindness and disfigurement. Recently, we conducted 4 different temporalis muscle transfer (TMT) methods over the last 4 years to reduce ptosis. The methods used included Brown-McDowell, McCord-Codner, modified Gillies-Anderson, and modified Gillies. Seventy-five TMT operations in 60 patients were performed between 2011 and 2014. The mean age was 70.1. Fifteen patients had bilateral TMT procedures. As a result, ptosis appeared in 14(18.7%) of 75 TMT procedures for 4 years. To prevent or correct this complication, the following 4 technical refinements have simplified the surgery and yield better surgical outcomes. First, an increase in the length of the temporalis muscle flap to approximately 8 cm with a parallel course to the lateral canthus will reduce oblique pull. Second, the width of the fascia sling in the upper eyelid is narrowed (3-4 mm) to reduce weight on the eyelid. Third, the fascia sling in the upper lid should not be located along the full length of the upper lid but terminate 3.5 cm medial to lateral canthal tendon and in other words, should not be tied at the medial canthal tendon to reduce tension and weight. Lastly, the fascia sling in the eyelid should be located shallow (probably in subdermal layer) and as near as possible to the lid margin to prevent any functional disturbance in levator aponeurosis. PMID:26674897

  1. Comparison of Surgical Outcomes Between Short-Segment Open and Percutaneous Pedicle Screw Fixation Techniques for Thoracolumbar Fractures.

    PubMed

    Fu, Zhiguo; Zhang, Xi; Shi, Yaohua; Dong, Qirong

    2016-01-01

    BACKGROUND This study aimed to compare the surgical outcomes between open pedicle screw fixation (OPSF) and percutaneous pedicle screw fixation (PPSF) for the treatment of thoracolumbar fractures, which has received scant research attention to date. MATERIAL AND METHODS Eight-four patients with acute and subacute thoracolumbar fractures who were treated with SSPSF from January 2013 to June 2014 at the Changzhou Hospital of Traditional Chinese Medicine (Changzhou, China) were retrospectively reviewed. The patients were divided into 4 groups: the OPSF with 4 basic screws (OPSF-4) group, the OPSF with 4 basic and 2 additional screws (OPSF-6) group, the PPSF with 4 basic screws (PPSF-4) group, and the PPSF with 4 basic and 2 additional screws (PPSF-6) group. The intraoperative, immediate postoperative, and over 1-year follow-up outcomes were evaluated and compared among these groups. RESULTS Blood loss in the PPSF-4 group and the PPSF-6 group was significantly less than in the OPSF-4 group and the OPSF-6 group (P<0.05). The OPSF-6 group exhibited significantly higher immediate postoperative correction percentage of anterior column height of fractured vertebra than the other 3 groups (P<0.05), and higher correction of sagittal regional Cobb angle and kyphotic angle of injured vertebra than in the PPSF-4 and -6 groups (P<0.05). In addition, there was no significant difference in the correction loss of percentage of anterior column height, and loss of sagittal Cobb angle and kyphotic angle of fractured vertebrae at final follow-up among the 4 groups (P>0.05). CONCLUSIONS OPSF with 6 screws had an advantage in the correction of injured vertebral height and kyphosis, and PPSF reduced the intraoperative blood loss of patients. PMID:27602557

  2. A Constrainted Design Approach for NLF Airfoils by Coupling Inverse Design and Optimal Techniques

    NASA Astrophysics Data System (ADS)

    Deng, L.; Gao, Y. W.; Qiao, Z. D.

    2011-09-01

    In present paper, a design method for natural laminar flow (NLF) airfoils with a substantial amount of natural laminar flow on both surfaces by coupling inverse design method and optimal technique is developed. The N-factor method is used to design the target pressure distributions before pressure recovery region with desired transition locations while maintaining aerodynamics constraints. The pressure in recovery region is designed according to Stratford separation criteria to prevent the laminar separation. In order to improve the off-design performance in inverse design, a multi-point inverse design is performed. An optimal technique based on response surface methodology (RSM) is used to calculate the target airfoil shapes according to the designed target pressure distributions. The set of design points is selected to satisfy the D-optimality and the reduced quadratic polynomial RS models without the 2nd-order cross items are constructed to reduce the computational cost. The design cases indicated that by the coupling-method developed in present paper, the inverse design method can be used in multi-point design to improve the off-design performance and the airfoils designed have the desired transition locations and maintain the aerodynamics constraints while the thickness constraint is difficult to meet in this design procedure.

  3. The suitability of selected multidisciplinary design and optimization techniques to conceptual aerospace vehicle design

    NASA Technical Reports Server (NTRS)

    Olds, John R.

    1992-01-01

    Four methods for preliminary aerospace vehicle design are reviewed. The first three methods (classical optimization, system decomposition, and system sensitivity analysis (SSA)) employ numerical optimization techniques and numerical gradients to feed back changes in the design variables. The optimum solution is determined by stepping through a series of designs toward a final solution. Of these three, SSA is argued to be the most applicable to a large-scale highly coupled vehicle design where an accurate minimum of an objective function is required. With SSA, several tasks can be performed in parallel. The techniques of classical optimization and decomposition can be included in SSA, resulting in a very powerful design method. The Taguchi method is more of a 'smart' parametric design method that analyzes variable trends and interactions over designer specified ranges with a minimum of experimental analysis runs. Its advantages are its relative ease of use, ability to handle discrete variables, and ability to characterize the entire design space with a minimum of analysis runs.

  4. Artificial intelligent techniques for optimizing water allocation in a reservoir watershed

    NASA Astrophysics Data System (ADS)

    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.

  5. On large-scale nonlinear programming techniques for solving optimal control problems

    SciTech Connect

    Faco, J.L.D.

    1994-12-31

    The formulation of decision problems by Optimal Control Theory allows the consideration of their dynamic structure and parameters estimation. This paper deals with techniques for choosing directions in the iterative solution of discrete-time optimal control problems. A unified formulation incorporates nonlinear performance criteria and dynamic equations, time delays, bounded state and control variables, free planning horizon and variable initial state vector. In general they are characterized by a large number of variables, mostly when arising from discretization of continuous-time optimal control or calculus of variations problems. In a GRG context the staircase structure of the jacobian matrix of the dynamic equations is exploited in the choice of basic and super basic variables and when changes of basis occur along the process. The search directions of the bound constrained nonlinear programming problem in the reduced space of the super basic variables are computed by large-scale NLP techniques. A modified Polak-Ribiere conjugate gradient method and a limited storage quasi-Newton BFGS method are analyzed and modifications to deal with the bounds on the variables are suggested based on projected gradient devices with specific linesearches. Some practical models are presented for electric generation planning and fishery management, and the application of the code GRECO - Gradient REduit pour la Commande Optimale - is discussed.

  6. Integration of ab-initio nuclear calculation with derivative free optimization technique

    SciTech Connect

    Sharda, Anurag

    2008-01-01

    Optimization techniques are finding their inroads into the field of nuclear physics calculations where the objective functions are very complex and computationally intensive. A vast space of parameters needs searching to obtain a good match between theoretical (computed) and experimental observables, such as energy levels and spectra. Manual calculation defies the scope of such complex calculation and are prone to error at the same time. This body of work attempts to formulate a design and implement it which would integrate the ab initio nuclear physics code MFDn and the VTDIRECT95 code. VTDIRECT95 is a Fortran95 suite of parallel code implementing the derivative-free optimization algorithm DIRECT. Proposed design is implemented for a serial and parallel version of the optimization technique. Experiment with the initial implementation of the design showing good matches for several single-nucleus cases are conducted. Determination and assignment of appropriate number of processors for parallel integration code is implemented to increase the efficiency and resource utilization in the case of multiple nuclei parameter search.

  7. A review on optimization production and upgrading biogas through CO2 removal using various techniques.

    PubMed

    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. PMID:24293277

  8. Scrotal phalloplasty: A novel surgical technique for aphallia during infancy and childhood by pre-anal anterior coronal approach

    PubMed Central

    Bajpai, Minu

    2012-01-01

    All the currently known reconstructions for aphallia are carried out around puberty. We describe a novel technique as a temporizing procedure which would see the patient through childhood. This would not cause any hindrance while undertaking any of the other established procedures later on after puberty. PMID:23243368

  9. Optimization models and techniques for implementation and pricing of electricity markets

    NASA Astrophysics Data System (ADS)

    Madrigal Martinez, Marcelino

    Vertically integrated electric power systems extensively use optimization models and solution techniques to guide their optimal operation and planning. The advent of electric power systems re-structuring has created needs for new optimization tools and the revision of the inherited ones from the vertical integration era into the market environment. This thesis presents further developments on the use of optimization models and techniques for implementation and pricing of primary electricity markets. New models, solution approaches, and price setting alternatives are proposed. Three different modeling groups are studied. The first modeling group considers simplified continuous and discrete models for power pool auctions driven by central-cost minimization. The direct solution of the dual problems, and the use of a Branch-and-Bound algorithm to solve the primal, allows to identify the effects of disequilibrium, and different price setting alternatives over the existence of multiple solutions. It is shown that particular pricing rules worsen the conflict of interest that arise when multiple solutions exist under disequilibrium. A price-setting alternative based on dual variables is shown to diminish such conflict. The second modeling group considers the unit commitment problem. An interior-point/cutting-plane method is proposed for the solution of the dual problem. The new method has better convergence characteristics and does not suffer from the parameter tuning drawback as previous methods The robustness characteristics of the interior-point/cutting-plane method, combined with a non-uniform price setting alternative, show that the conflict of interest is diminished when multiple near optimal solutions exist. The non-uniform price setting alternative is compared to a classic average pricing rule. The last modeling group concerns to a new type of linear network-constrained clearing system models for daily markets for power and spinning reserve. A new model and

  10. A Survey on Optimal Signal Processing Techniques Applied to Improve the Performance of Mechanical Sensors in Automotive Applications

    PubMed Central

    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 filters and optimal filters for automotive sensors is made, and the current state of the art of the application of robust and optimal control and signal processing techniques to the design of the intelligent (or smart) sensors that today's cars need is presented through several experimental results that show that the fusion of intelligent sensors and optimal signal processing techniques is the clear way to go. However, the switch between the traditional methods of designing automotive sensors and the new ones cannot be done overnight because there are some open research issues that have to be solved. This paper draws attention to one of the open research issues and tries to arouse researcher's interest in the fusion of intelligent sensors and optimal signal processing techniques.

  11. Overall Essen’s experience with the E-vita open hybrid stent graft system and evolution of the surgical technique

    PubMed Central

    Dohle, Daniel; Benedik, Jaroslav; Lieder, Helmut; Jakob, Heinz

    2013-01-01

    Background The hybrid stent graft prosthesis E-vita open was designed and introduced by us in 2005 to avoid a two-stage surgical approach in the surgical treatment of complex thoracic aortic disease. Experience in ascending aortic and arch replacement with simultaneous stent grafting of the descending aorta was accumulated over the past 8 years. Facilitation of surgical technique by moving the distal suture line from Zone 3 into Zone 2 took place in 2009. We report our mid-term single-center experience comparing both surgical periods. Methods Between January 2005 and July 2013 a total of 132 patients (mean age 59±11 years) underwent one stage surgery for acute (AAD, n=74), chronic aortic dissection (CAD, n=35) or an extensive thoracic aortic aneurysm (TAA, n=23). Patients were separated in two groups according to distal anastomosis level in Zone 2 (Z2, 41/132) and Zone 3 (Z3, 91/132). Outcome, ischemic and operative times as well as adverse events were monitored during follow up. Results Overall in-hospital mortality was 13% (17/132) without difference between the groups. However, Zone 2 anastomosis resulted in reduction of cardioplegic arrest (117±39 vs. 147±35 minutes; P<0.001), selective cerebral perfusion (52±15 vs. 68±18 minutes; P<0.001) and visceral ischemic time (51±19 vs. 72±23 minutes; P<0.001). The incidence of postoperative temporary hemodialysis decreased from 40% to 20% in Z2 (P=0.028), postoperative re-exploration rate from 15% to 2% (P=0.037). No difference was found in dissection with complete false lumen thrombosis in 83% (90/109) within 10 days, as well as in TAA, where 100% aneurysm exclusion was observed. Three-year survival, freedom from thoracoabdominal aortic surgery and endovascular repair was 93%, 88%, 88%, respectively. Overall 5-year survival was 76% in AAD, 85% in CAD and 79% in TAA patients. Conclusions The dimension of surgery could be successfully reduced, indicated by significantly shortened ischemic times and postoperative

  12. An optimal technique for constraint-based image restoration and reconstruction

    NASA Astrophysics Data System (ADS)

    Leahy, Richard M.; Goutis, Costas E.

    1986-12-01

    A new technique for finding an optimal feasible solution to the general image reconstruction and restoration problem is described. This method allows the use of prior knowledge of the properties of both the solution and any noise present on the data. The problem is formulated as the optimization of a cost function over the intersection of a number of convex constraint sets; each set being defined as containing those solutions consistent with a particular constraint. A duality theorem is then applied to yield a dual problem in which the unknown image is replaced by a model defined in terms of a finite dimensional parameter vector and the kernels of the inteegral equations relating the data and solution. The dual problem may then be solved for the model parameters using a gradient descent algorithm. This method serves as an alternative to the primal constrained optimization and projection onto convex sets (POCS) algorithms. Problems in which this new approach is appropriate are discussed. An example is given for image reconstruction from noisy projection data; applying the dual method results in a fast nonlinear algorithm. Simulation results demonstrate the superiority of the optimal feasible solution over one obtained using a suboptimal approach.

  13. Design and optimization of a total vaporization technique coupled to solid-phase microextraction.

    PubMed

    Rainey, Christina L; Bors, Dana E; Goodpaster, John V

    2014-11-18

    Solid-phase microextraction (SPME) is a popular sampling technique in which chemical compounds are collected with a sorbent-coated fiber and then desorbed into an analytical instrument such as a liquid or gas chromatograph. Typically, this technique is used to sample the headspace above a solid or liquid sample (headspace SPME), or to directly sample a liquid (immersion SPME). However, this work demonstrates an alternative approach where the sample is totally vaporized (total vaporization SPME or TV-SPME) so that analytes partition directly between the vapor phase and the SPME fiber. The implementation of this technique is demonstrated with polydimethylsiloxane-divinylbenzene (PDMS-DVB) and polyacrylate (PA) coated SPME fibers for the collection of nicotine and its metabolite cotinine in chloroform extracts. The most important method parameters were optimized using a central composite design, and this resulted in an optimal extraction temperature (96 °C), extraction time (60 min), and sample volume (120 μL). In this application, large sample volumes up to 210 μL were analyzed using a volatile solvent such as chloroform at elevated temperatures. The sensitivity of TV-SPME is nearly twice that of liquid injection for cotinine and nearly 6 times higher for nicotine. In addition, increased sampling selectivity of TV-SPME permits detection of both nicotine and cotinine in hair as biomarkers of tobacco use where in the past the detection of cotinine has not been achieved by conventional SPME. PMID:25313649

  14. Optimized Scheduling Technique of Null Subcarriers for Peak Power Control in 3GPP LTE Downlink

    PubMed Central

    Park, Sang Kyu

    2014-01-01

    Orthogonal frequency division multiple access (OFDMA) is a key multiple access technique for the long term evolution (LTE) downlink. However, high peak-to-average power ratio (PAPR) can cause the degradation of power efficiency. The well-known PAPR reduction technique, dummy sequence insertion (DSI), can be a realistic solution because of its structural simplicity. However, the large usage of subcarriers for the dummy sequences may decrease the transmitted data rate in the DSI scheme. In this paper, a novel DSI scheme is applied to the LTE system. Firstly, we obtain the null subcarriers in single-input single-output (SISO) and multiple-input multiple-output (MIMO) systems, respectively; then, optimized dummy sequences are inserted into the obtained null subcarrier. Simulation results show that Walsh-Hadamard transform (WHT) sequence is the best for the dummy sequence and the ratio of 16 to 20 for the WHT and randomly generated sequences has the maximum PAPR reduction performance. The number of near optimal iteration is derived to prevent exhausted iterations. It is also shown that there is no bit error rate (BER) degradation with the proposed technique in LTE downlink system. PMID:24883376

  15. Parameterized CAD techniques implementation for the fatigue behaviour optimization of a service chamber

    NASA Astrophysics Data System (ADS)

    Sánchez, H. T.; Estrems, M.; Franco, P.; Faura, F.

    2009-11-01

    In recent years, the market of heat exchangers is increasingly demanding new products in short cycle time, which means that both the design and manufacturing stages must be extremely reduced. The design stage can be reduced by means of CAD-based parametric design techniques. The methodology presented in this proceeding is based on the optimized control of geometric parameters of a service chamber of a heat exchanger by means of the Application Programming Interface (API) provided by the Solidworks CAD package. Using this implementation, a set of different design configurations of the service chamber made of stainless steel AISI 316 are studied by means of the FE method. As a result of this study, a set of knowledge rules based on the fatigue behaviour are constructed and integrated into the design optimization process.

  16. Optimization techniques applied to passive measures for in-orbit spacecraft survivability

    NASA Technical Reports Server (NTRS)

    Mog, Robert A.; Price, D. Marvin

    1991-01-01

    Spacecraft designers have always been concerned about the effects of meteoroid impacts on mission safety. The engineering solution to this problem has generally been to erect a bumper or shield placed outboard from the spacecraft wall to disrupt/deflect the incoming projectiles. Spacecraft designers have a number of tools at their disposal to aid in the design process. These include hypervelocity impact testing, analytic impact predictors, and hydrodynamic codes. Analytic impact predictors generally provide the best quick-look estimate of design tradeoffs. The most complete way to determine the characteristics of an analytic impact predictor is through optimization of the protective structures design problem formulated with the predictor of interest. Space Station Freedom protective structures design insight is provided through the coupling of design/material requirements, hypervelocity impact phenomenology, meteoroid and space debris environment sensitivities, optimization techniques and operations research strategies, and mission scenarios. Major results are presented.

  17. Human motion planning based on recursive dynamics and optimal control techniques

    NASA Technical Reports Server (NTRS)

    Lo, Janzen; Huang, Gang; Metaxas, Dimitris

    2002-01-01

    This paper presents an efficient optimal control and recursive dynamics-based computer animation system for simulating and controlling the motion of articulated figures. A quasi-Newton nonlinear programming technique (super-linear convergence) is implemented to solve minimum torque-based human motion-planning problems. The explicit analytical gradients needed in the dynamics are derived using a matrix exponential formulation and Lie algebra. Cubic spline functions are used to make the search space for an optimal solution finite. Based on our formulations, our method is well conditioned and robust, in addition to being computationally efficient. To better illustrate the efficiency of our method, we present results of natural looking and physically correct human motions for a variety of human motion tasks involving open and closed loop kinematic chains.

  18. The results of anterior radical debridement and anterior instrumentation in Pott's disease and comparison with other surgical techniques.

    PubMed

    Benli, I T; Kiş, M; Akalin, S; Citak, M; Kanevetçi, S; Duman, E

    2000-04-01

    Classic procedure in the treatment of vertebral tuberculosis is drainage of the abscess, curettage of the devitalized vertebra and application of antituberculous chemotherapy regimen. Posterior instrumentation results are encouraging in the prevention or treatment of late kyphosis; however, a second stage operation is needed. Recently, posterolateral or transpedicular drainage without anterior drainage or posterior instrumentation following anterior drainage in the same session is preferred to avoid kyphotic deformity. Seventy-six patients with spinal tuberculosis were operated in the 1st Department of Orthopaedics and Traumatology, Ankara Social Security Hospital, between January 1987 and January 1997. There were four children in our series. Average follow-up period was 36.1 +/- 14.5 months and the average age at the time of operation was 40.8 +/- 15.2 years. This study reports the surgical results of 45 patients with Pott's disease who had anterior radical debridement with anterior fusion and anterior instrumentation [14 patients with Z-plate and 31 patients with Cotrel-Dubousset-Hopf (CDH system)]. The results are compared with those of 8 patients who had posterolateral drainage and posterior fusion, 12 patients who had only anterior drainage and anterior strut grafting and, 11 patients who had posterior instrumentation following anterior radical debridement in the same session in terms of fusion rates, correction of kyphotic deformity, recurrence rate and clinical results. All patients had one year consecutive triple drug therapy. Preoperative 23.2 degrees +/- 12.5 degrees local kyphosis angle was lowered to 6.1 degrees +/- 6.9 degrees with a correction rate of 77.4 +/- 22.3%. When the other three groups which had been instrumented were compared, the correction rates in the local kyphosis angle values were not statistically different and the variation in loss of correction at the last follow-up was also statistically insignificant. The sagittal contour of the

  19. Oncoplastic Surgical Techniques for Personalized Breast Conserving Surgery in Breast Cancer Patient with Small to Moderate Sized Breast

    PubMed Central

    Yang, Jung Dug; Lee, Jeong Woo; Kim, Wan Wook; Jung, Jin Hyang

    2011-01-01

    Oncoplastic surgery has revolutionized the field of breast conserving surgery (BCS). The final aims of this technique are to obtain an adequate resection margin that will reduce the rate of local recurrence while simultaneously improving cosmetic outcomes. To obtain successful results after oncoplastic surgery, it is imperative that patients be risk-stratified based on risk factors associated with positive margins, that relevant imaging studies be reviewed, and that the confirmation of negative margins be confirmed during the initial operation. Patients who had small- to moderate-sized breasts are the most likely to be dissatisfied with the cosmetic outcome of surgery, even if the defect is small; therefore, oncoplastic surgery in this population is warranted. Reconstruction of the remaining breast tissue is divided into volume displacement and volume replacement techniques. The use of the various oncoplastic surgeries is based on tumor location and excised breast volume. If the excised volume is less than 100 g, the tumor location is used to determine which technique should be used, with the most commonly used technique being volume displacement. However, if the excised volume is greater than 100 g, the volume replacement method is generally used, and in cases where more than 150 g is excised, the latissimus dorsi myocutaneous flap may be used to obtain a pleasing cosmetic result. The local recurrence rate after oncoplastic surgery was lower than that of conventional BCS, as oncoplastic surgery reduced the rate of positive resection margins by resecting a wider section of glandular tissue. If the surgeon understands the advantages and disadvantages of oncoplastic surgery, and the multidisciplinary breast team is able to successfully collaborate, then the success rate of BCS with partial breast reconstruction can be increased while also yielding a cosmetically appealing outcome. PMID:22323910

  20. Macroscopic optical imaging technique for wide-field estimation of fluorescence depth in optically turbid media for application in brain tumor surgical guidance

    NASA Astrophysics Data System (ADS)

    Kolste, Kolbein K.; Kanick, Stephen C.; Valdés, Pablo A.; Jermyn, Michael; Wilson, Brian C.; Roberts, David W.; Paulsen, Keith D.; Leblond, Frederic

    2015-02-01

    A diffuse imaging method is presented that enables wide-field estimation of the depth of fluorescent molecular markers in turbid media by quantifying the deformation of the detected fluorescence spectra due to the wavelength-dependent light attenuation by overlying tissue. This is achieved by measuring the ratio of the fluorescence at two wavelengths in combination with normalization techniques based on diffuse reflectance measurements to evaluate tissue attenuation variations for different depths. It is demonstrated that fluorescence topography can be achieved up to a 5 mm depth using a near-infrared dye with millimeter depth accuracy in turbid media having optical properties representative of normal brain tissue. Wide-field depth estimates are made using optical technology integrated onto a commercial surgical microscope, making this approach feasible for real-world applications.

  1. Macroscopic optical imaging technique for wide-field estimation of fluorescence depth in optically turbid media for application in brain tumor surgical guidance

    PubMed Central

    Kolste, Kolbein K.; Kanick, Stephen C.; Valdés, Pablo A.; Jermyn, Michael; Wilson, Brian C.; Roberts, David W.; Paulsen, Keith D.; Leblond, Frederic

    2015-01-01

    Abstract. A diffuse imaging method is presented that enables wide-field estimation of the depth of fluorescent molecular markers in turbid media by quantifying the deformation of the detected fluorescence spectra due to the wavelength-dependent light attenuation by overlying tissue. This is achieved by measuring the ratio of the fluorescence at two wavelengths in combination with normalization techniques based on diffuse reflectance measurements to evaluate tissue attenuation variations for different depths. It is demonstrated that fluorescence topography can be achieved up to a 5 mm depth using a near-infrared dye with millimeter depth accuracy in turbid media having optical properties representative of normal brain tissue. Wide-field depth estimates are made using optical technology integrated onto a commercial surgical microscope, making this approach feasible for real-world applications. PMID:25652704

  2. Occurrence and surgical repair of third degree perineal lacerations in adult female camels (Camelus dromedarius) by one-stage (Goetz) technique

    PubMed Central

    Anwar, S.; Purohit, G.N.

    2013-01-01

    Retrospective analysis of third degree perineal lacerations in 7 female camels (6-17 yrs of age) that were surgically corrected by one stage repair (Goetz technique) is presented. Majority (3/7) of the camels was primiparous and all parturitions had a history of calving assistance. Six (6/7) camels recovered by first intention of healing. Dehiscence of perineal structure occurred in only one camel due to infection and healed by second intention. Subsequent matings resulted in pregnancy in four camels and one camel died due to unrelated causes. We conclude that perineal lacerations can occur in primiparous camels with difficult assisted deliveries and that one stage repair of perineal lacerations in camels improves the perineal conformation and such camels may easily regain normal fertility. PMID:26623316

  3. A new surgical technique to facilitate osteochondral autograft transfer in osteochondral defects of the capitellum: a case report.

    PubMed

    Bilsel, Kerem; Demirhan, Mehmet; Atalar, Ata Can; Akkaya, Semih

    2010-01-01

    A 17-year-old boy who was engaged in amateur weightlifting and body building presented with complaints of right elbow pain and limitation in elbow range of motion. Plain x-rays and magnetic resonance imaging showed an osteochondral defect in the medial third of the capitellum. At surgery, as a new technique, the lateral collateral ligament was detached from the humeral attachment to provide access to the capitellum with a clear and perpendicular exposure. Following removal of loose fragments within the joint, an osteochondral graft harvested from the lateral femoral condyle was implanted to the defect area of the capitellum. Postoperative radiologic controls showed that the defect was entirely filled by the graft with appropriate graft height. On follow-up examination at 12 months, the patient did not have any complaint about his elbow, and had no limitation of movement compared to the left elbow. Magnetic resonance imaging showed that the graft was successfully adapted to the recipient site without any sign of loosening. At final follow-up 40 months after surgery, the surface of the articular cartilage appeared normal. The range of elbow motion was preserved and the patient had no restriction in daily and sports activities. Considering technical difficulties posed by the narrow and complex structure of the elbow joint, this new technique involving detachment of the lateral collateral ligament facilitates perpendicular implantation of the graft. In our opinion, utilization of this new technique will improve functional and radiological results of osteochondral autograft transfer. PMID:20513997

  4. Early results and review of the literature of a novel hybrid surgical technique combining cervical arthrodesis and disc arthroplasty for treating multilevel degenerative disc disease: opposite or complementary techniques?

    PubMed Central

    Assietti, Roberto; Corbino, Leonardo; Olindo, Giuseppe; Foti, Pietro V.; Russo, Vittorio; Albanese, Vincenzo

    2009-01-01

    We report the clinical and radiological results on the safety and efficacy of an unusual surgical strategy coupling anterior cervical discectomy and fusion and total disc replacement in a single-stage procedure, in patients with symptomatic, multilevel cervical degenerative disc disease (DDD). The proposed hybrid, single-stage, fusion–nonfusion technique aims either at restoring or maintaining motion where appropriate or favouring bony fusion when indicated by degenerative changes. Twenty-four patients (mean age 46.7 years) with symptomatic, multilevel DDD, either soft disc hernia or different stage spondylosis per single level, with predominant anterior myeloradicular compression and absence of severe alterations of cervical spine sagittal alignment, have been operated using such hybrid technique. Fifteen patients underwent a two-level surgery, seven patients received a three-level surgery and two a four-level procedure, for a total of 59 implanted devices (27 disc prostheses and 32 cages). Follow-up ranged between 12 and 40 months (mean 23.8 months). In all but one patient clinical follow-up (neurological examination, Nurick scale, NDI, SF-36) demonstrated significant improvement; radiological evaluation showed functioning disc prostheses (total range of motion 3–15°) and fusion through cages. None of the patients needed revision surgery for persisting or recurring symptoms, procedure-related complications or devices dislocations. To the authors’ best knowledge, this is the first study with the longest available follow-up describing a different concept in the management of cervical multilevel DDD. Although larger series with longer follow-up are needed, in selected cases of symptomatic multilevel DDD, the proposed surgical strategy appears to be a safe and reliable application of combined arthroplasty and arthrodesis during a single surgical procedure. PMID:19415346

  5. A technique for optimal temperature estimation for modeling sunrise/sunset thermal snap disturbance torque

    NASA Technical Reports Server (NTRS)

    Zimbelman, D. F.; Dennehy, C. J.; Welch, R. V.; Born, G. H.

    1990-01-01

    A predictive temperature estimation technique which can be used to drive a model of the Sunrise/Sunset thermal 'snap' disturbance torque experienced by low Earth orbiting spacecraft is described. The twice per orbit impulsive disturbance torque is attributed to vehicle passage in and out of the Earth's shadow cone (umbra), during which large flexible appendages undergo rapidly changing thermal conditions. Flexible members, in particular solar arrays, experience rapid cooling during umbra entrance (Sunset) and rapid heating during exit (Sunrise). The thermal 'snap' phenomena has been observed during normal on-orbit operations of both the LANDSAT-4 satellite and the Communications Technology Satellite (CTS). Thermal 'snap' has also been predicted to be a dominant source of error for the TOPEX satellite. The fundamental equations used to model the Sunrise/Sunset thermal 'snap' disturbance torque for a typical solar array like structure will be described. For this derivation the array is assumed to be a thin, cantilevered beam. The time varying thermal gradient is shown to be the driving force behind predicting the thermal 'snap' disturbance torque and therefore motivates the need for accurate estimates of temperature. The development of a technique to optimally estimate appendage surface temperature is highlighted. The objective analysis method used is structured on the Gauss-Markov Theorem and provides an optimal temperature estimate at a prescribed location given data from a distributed thermal sensor network. The optimally estimated surface temperatures could then be used to compute the thermal gradient across the body. The estimation technique is demonstrated using a typical satellite solar array.

  6. The Analysis and Design of Low Boom Configurations Using CFD and Numerical Optimization Techniques

    NASA Technical Reports Server (NTRS)

    Siclari, Michael J.

    1999-01-01

    The use of computational fluid dynamics (CFD) for the analysis of sonic booms generated by aircraft has been shown to increase the accuracy and reliability of predictions. CFD takes into account important three-dimensional and nonlinear effects that are generally neglected by modified linear theory (MLT) methods. Up to the present time, CFD methods have been primarily used for analysis or prediction. Some investigators have used CFD to impact the design of low boom configurations using trial and error methods. One investigator developed a hybrid design method using a combination of Modified Linear Theory (e.g. F-functions) and CFD to provide equivalent area due to lift driven by a numerical optimizer to redesign or modify an existing configuration to achieve a shaped sonic boom signature. A three-dimensional design methodology has not yet been developed that completely uses nonlinear methods or CFD. Constrained numerical optimization techniques have existed for some time. Many of these methods use gradients to search for the minimum of a specified objective function subject to a variety of design variable bounds, linear and nonlinear constraints. Gradient based design optimization methods require the determination of the objective function gradients with respect to each of the design variables. These optimization methods are efficient and work well if the gradients can be obtained analytically. If analytical gradients are not available, the objective gradients or derivatives with respect to the design variables must be obtained numerically. To obtain numerical gradients, say, for 10 design variables, might require anywhere from 10 to 20 objective function evaluations. Typically, 5-10 global iterations of the optimizer are required to minimize the objective function. In terms of using CFD as a design optimization tool, the numerical evaluation of gradients can require anywhere from 100 to 200 CFD computations per design for only 10 design variables. If one CFD

  7. Optimization techniques applied to passive measures for in-orbit spacecraft survivability

    NASA Technical Reports Server (NTRS)

    Mog, Robert A.; Helba, Michael J.; Hill, Janeil B.

    1992-01-01

    The purpose of this research is to provide Space Station Freedom protective structures design insight through the coupling of design/material requirements, hypervelocity impact phenomenology, meteoroid and space debris environment sensitivities, optimization techniques and operations research strategies, and mission scenarios. The goals of the research are: (1) to develop a Monte Carlo simulation tool which will provide top level insight for Space Station protective structures designers; (2) to develop advanced shielding concepts relevant to Space Station Freedom using unique multiple bumper approaches; and (3) to investigate projectile shape effects on protective structures design.

  8. Use of a microdebrider for corporeal excavation and penile prosthesis implantation in men with severely fibrosed corpora cavernosa: a new minimal invasive surgical technique

    PubMed Central

    Bozkurt, İbrahim Halil; Yonguç, Tarık; Aydoğdu, Özgü; Değirmenci, Tansu; Arslan, Murat; Minareci, Süleyman

    2015-01-01

    Objective To propose a new minimal invasive surgical technique using a microdebrider (shaver) to excavate the fibrosed corpora cavernosa for penile prosthesis implantation in patients with severe fibrosis. Material and methods Two patients with severe corporeal fibrosis were implanted with a penile prosthesis using this technique. In the first patient, fibrosis was due to neglected idiopathic ischemic priapism and the second patient had his prosthesis extruded because of erosion in another center. Both patients were counseled about the procedure and the possible complications related to the experimental nature of the technique. A written informed consent was obtained from both patients. Excavation of the corpora was performed using microdebrider in both patients. Results Both operations were performed successfully without any intraoperative complications, including urethral injury or perforation of the tunica. The mean operation time was 57 min. The postoperative period was uneventful without any infection, migration, erosion, or mechanical failure. The penile length was increased nearly 2 cm in both patients, and the penile girth was increased around 30% in the patient who underwent inflatable penile prosthesis implantation. Conclusion The microdebrider potentially provides an important advance in patients with severe corporeal fibrosis to excavate the fibrosed corpora cavernosa for penile prosthesis implantation. The main advantages include fast, safe, and effective excavation of fibrous corpora cavernosa adequate for a satisfactory penile prosthesis implantation. PMID:26516594

  9. New efficient optimizing techniques for Kalman filters and numerical weather prediction models

    NASA Astrophysics Data System (ADS)

    Famelis, Ioannis; Galanis, George; Liakatas, Aristotelis

    2016-06-01

    The need for accurate local environmental predictions and simulations beyond the classical meteorological forecasts are increasing the last years due to the great number of applications that are directly or not affected: renewable energy resource assessment, natural hazards early warning systems, global warming and questions on the climate change can be listed among them. Within this framework the utilization of numerical weather and wave prediction systems in conjunction with advanced statistical techniques that support the elimination of the model bias and the reduction of the error variability may successfully address the above issues. In the present work, new optimization methods are studied and tested in selected areas of Greece where the use of renewable energy sources is of critical. The added value of the proposed work is due to the solid mathematical background adopted making use of Information Geometry and Statistical techniques, new versions of Kalman filters and state of the art numerical analysis tools.

  10. Design and optimization of stepped austempered ductile iron using characterization techniques

    SciTech Connect

    Hernández-Rivera, J.L.; Garay-Reyes, C.G.; Campos-Cambranis, R.E.; Cruz-Rivera, J.J.

    2013-09-15

    Conventional characterization techniques such as dilatometry, X-ray diffraction and metallography were used to select and optimize temperatures and times for conventional and stepped austempering. Austenitization and conventional austempering time was selected when the dilatometry graphs showed a constant expansion value. A special heat color-etching technique was applied to distinguish between the untransformed austenite and high carbon stabilized austenite which had formed during the treatments. Finally, it was found that carbide precipitation was absent during the stepped austempering in contrast to conventional austempering, on which carbide evidence was found. - Highlights: • Dilatometry helped to establish austenitization and austempering parameters. • Untransformed austenite was present even for longer processing times. • Ausferrite formed during stepped austempering caused important reinforcement effect. • Carbide precipitation was absent during stepped treatment.

  11. A model based technique for the design of flight directors. [optimal control models

    NASA Technical Reports Server (NTRS)

    Levison, W. H.

    1973-01-01

    A new technique for designing flight directors is discussed. This technique uses the optimal-control pilot/vehicle model to determine the appropriate control strategy. The dynamics of this control strategy are then incorporated into the director control laws, thereby enabling the pilot to operate at a significantly lower workload. A preliminary design of a control director for maintaining a STOL vehicle on the approach path in the presence of random air turbulence is evaluated. By selecting model parameters in terms of allowable path deviations and pilot workload levels, a set of director laws is achieved which allows improved system performance at reduced workload levels. The pilot acts essentially as a proportional controller with regard to the director signals, and control motions are compatible with those appropriate to status-only displays.

  12. Multiscale Surgical Telerobots

    SciTech Connect

    Miles, R R; Seward, K P; Benett, W J; Tendick, F; Bentley, L; Stephan, P L

    2002-01-23

    A project was undertaken to improve robotic surgical tools for telerobotic minimally invasive surgery. The major objectives were to reduce the size of the tools to permit new surgical procedures in confined spaces such as the heart and to improve control of surgical tools by locating positional sensors and actuators at the end effector rather than external to the patient as is currently the state of the technology. A new compact end-effector with wrist-like flexibility was designed. Positional sensors based on MEMS microfabrication techniques were designed.

  13. A Novel Surgical Technique for Right-Sided Interrupted Aortic Arch by Interposition of a Pulmonary Autograft Tube.

    PubMed

    Kato, Nobuyasu; Yamagishi, Masaaki; Miyazaki, Takako; Maeda, Yoshinobu; Asada, Satoshi; Hongu, Hisayuki; Yamashita, Eijiro; Yaku, Hitoshi

    2016-08-01

    Right-sided interrupted aortic arch (IAA) is a rare cardiac anomaly. In general, the right bronchus sits higher than the left bronchus, so aortic arch reconstruction with a direct anastomosis has a risk of tracheal and bronchial obstruction. This report describes the successful definitive repair of a right-sided IAA in a 2.5-kg neonate by aortic arch reconstruction with a pulmonary autograft tube (PA tube). Postoperative three-dimensional multidetector computed tomography showed the reconstructed aortic arch without airway obstruction or aortic stenosis. The use of a PA tube is a simple and useful technique for aortic arch reconstruction in patients with a high risk of tracheal andbronchial obstruction, such as right-sided IAA. PMID:27449446

  14. A comparison of two global optimization algorithms with sequential niche technique for structural model updating

    NASA Astrophysics Data System (ADS)

    Shabbir, Faisal; Omenzetter, Piotr

    2014-04-01

    Much effort is devoted nowadays to derive accurate finite element (FE) models to be used for structural health monitoring, damage detection and assessment. However, formation of a FE model representative of the original structure is a difficult task. Model updating is a branch of optimization which calibrates the FE model by comparing the modal properties of the actual structure with these of the FE predictions. As the number of experimental measurements is usually much smaller than the number of uncertain parameters, and, consequently, not all uncertain parameters are selected for model updating, different local minima may exist in the solution space. Experimental noise further exacerbates the problem. The attainment of a global solution in a multi-dimensional search space is a challenging problem. Global optimization algorithms (GOAs) have received interest in the previous decade to solve this problem, but no GOA can ensure the detection of the global minimum either. To counter this problem, a combination of GOA with sequential niche technique (SNT) has been proposed in this research which systematically searches the whole solution space. A dynamically tested full scale pedestrian bridge is taken as a case study. Two different GOAs, namely particle swarm optimization (PSO) and genetic algorithm (GA), are investigated in combination with SNT. The results of these GOA are compared in terms of their efficiency in detecting global minima. The systematic search enables to find different solutions in the search space, thus increasing the confidence of finding the global minimum.

  15. Intraoperative optical coherence tomography using an optimized reflective optical relay, real-time heads-up display, and semitransparent surgical instrumentation

    NASA Astrophysics Data System (ADS)

    Tao, Yuankai K.; El-Haddad, Mohamed T.; Srivastava, Sunil K.; Feiler, Daniel; Noonan, Amanda I.; Rollins, Andrew M.; Ehlers, Justis P.

    2015-03-01

    Ophthalmic surgical maneuvers are currently limited by the ability of surgeons to visualize and manipulate semitransparent tissue layers as thin as tens of microns. We describe several iterative advances in iOCT technology, including a novel iOCT system, real-time heads-up display (HUD) feedback, visualization of intraoperative maneuvers, and OCT-compatible surgical instrumentation. Simulated surgical maneuvers were performed on freshly enucleated porcine eyes. Subretinal space cannulation with injection was performed and imaged using spatial compounding. The optical properties of semitransparent materials were quantified to identify OCT-compatible substrates, and surgical instrument prototypes were machined, including corneal, surgical picks, and retinal forceps.

  16. Applying Reflective Middleware Techniques to Optimize a QoS-enabled CORBA Component Model Implementation

    NASA Technical Reports Server (NTRS)

    Wang, Nanbor; Parameswaran, Kirthika; Kircher, Michael; Schmidt, Douglas

    2003-01-01

    Although existing CORBA specifications, such as Real-time CORBA and CORBA Messaging, address many end-to-end quality-of service (QoS) properties, they do not define strategies for configuring these properties into applications flexibly, transparently, and adaptively. Therefore, application developers must make these configuration decisions manually and explicitly, which is tedious, error-prone, and open sub-optimal. Although the recently adopted CORBA Component Model (CCM) does define a standard configuration framework for packaging and deploying software components, conventional CCM implementations focus on functionality rather than adaptive quality-of-service, which makes them unsuitable for next-generation applications with demanding QoS requirements. This paper presents three contributions to the study of middleware for QoS-enabled component-based applications. It outlines rejective middleware techniques designed to adaptively (1) select optimal communication mechanisms, (2) manage QoS properties of CORBA components in their contain- ers, and (3) (re)con$gure selected component executors dynamically. Based on our ongoing research on CORBA and the CCM, we believe the application of rejective techniques to component middleware will provide a dynamically adaptive and (re)configurable framework for COTS software that is well-suited for the QoS demands of next-generation applications.

  17. Applying Reflective Middleware Techniques to Optimize a QoS-enabled CORBA Component Model Implementation

    NASA Technical Reports Server (NTRS)

    Wang, Nanbor; Kircher, Michael; Schmidt, Douglas C.

    2000-01-01

    Although existing CORBA specifications, such as Real-time CORBA and CORBA Messaging, address many end-to-end quality-of-service (QoS) properties, they do not define strategies for configuring these properties into applications flexibly, transparently, and adaptively. Therefore, application developers must make these configuration decisions manually and explicitly, which is tedious, error-prone, and often sub-optimal. Although the recently adopted CORBA Component Model (CCM) does define a standard configuration frame-work for packaging and deploying software components, conventional CCM implementations focus on functionality rather than adaptive quality-of service, which makes them unsuitable for next-generation applications with demanding QoS requirements. This paper presents three contributions to the study of middleware for QoS-enabled component-based applications. It outlines reflective middleware techniques designed to adaptively: (1) select optimal communication mechanisms, (2) man- age QoS properties of CORBA components in their containers, and (3) (re)configure selected component executors dynamically. Based on our ongoing research on CORBA and the CCM, we believe the application of reflective techniques to component middleware will provide a dynamically adaptive and (re)configurable framework for COTS software that is well-suited for the QoS demands of next-generation applications.

  18. Optimization of MKID noise performance via readout technique for astronomical applications

    NASA Astrophysics Data System (ADS)

    Czakon, Nicole G.; Schlaerth, James A.; Day, Peter K.; Downes, Thomas P.; Duan, Ran P.; Gao, Jiansong; Glenn, Jason; Golwala, Sunil R.; Hollister, Matt I.; LeDuc, Henry G.; Mazin, Benjamin A.; Maloney, Philip R.; Noroozian, Omid; Nguyen, Hien T.; Sayers, Jack; Siegel, Seth; Vaillancourt, John E.; Vayonakis, Anastasios; Wilson, Philip R.; Zmuidzinas, Jonas

    2010-07-01

    Detectors employing superconducting microwave kinetic inductance detectors (MKIDs) can be read out by measuring changes in either the resonator frequency or dissipation. We will discuss the pros and cons of both methods, in particular, the readout method strategies being explored for the Multiwavelength Sub/millimeter Inductance Camera (MUSIC) to be commissioned at the CSO in 2010. As predicted theoretically and observed experimentally, the frequency responsivity is larger than the dissipation responsivity, by a factor of 2-4 under typical conditions. In the absence of any other noise contributions, it should be easier to overcome amplifier noise by simply using frequency readout. The resonators, however, exhibit excess frequency noise which has been ascribed to a surface distribution of two-level fluctuators sensitive to specific device geometries and fabrication techniques. Impressive dark noise performance has been achieved using modified resonator geometries employing interdigitated capacitors (IDCs). To date, our noise measurement and modeling efforts have assumed an onresonance readout, with the carrier power set well below the nonlinear regime. Several experimental indicators suggested to us that the optimal readout technique may in fact require a higher readout power, with the carrier tuned somewhat off resonance, and that a careful systematic study of the optimal readout conditions was needed. We will present the results of such a study, and discuss the optimum readout conditions as well as the performance that can be achieved relative to BLIP.

  19. Reducing the impact of a desalination plant using stochastic modeling and optimization techniques

    NASA Astrophysics Data System (ADS)

    Alcolea, Andres; Renard, Philippe; Mariethoz, Gregoire; Bertone, François

    2009-02-01

    SummaryWater is critical for economic growth in coastal areas. In this context, desalination has become an increasingly important technology over the last five decades. It often has environmental side effects, especially when the input water is pumped directly from the sea via intake pipelines. However, it is generally more efficient and cheaper to desalt brackish groundwater from beach wells rather than desalting seawater. Natural attenuation is also gained and hazards due to anthropogenic pollution of seawater are reduced. In order to minimize allocation and operational costs and impacts on groundwater resources, an optimum pumping network is required. Optimization techniques are often applied to this end. Because of aquifer heterogeneity, designing the optimum pumping network demands reliable characterizations of aquifer parameters. An optimum pumping network in a coastal aquifer in Oman, where a desalination plant currently pumps brackish groundwater at a rate of 1200 m 3/h for a freshwater production of 504 m 3/h (insufficient to satisfy the growing demand in the area) was designed using stochastic inverse modeling together with optimization techniques. The Monte Carlo analysis of 200 simulations of transmissivity and storage coefficient fields conditioned to the response to stresses of tidal fluctuation and three long term pumping tests was performed. These simulations are physically plausible and fit the available data well. Simulated transmissivity fields are used to design the optimum pumping configuration required to increase the current pumping rate to 9000 m 3/h, for a freshwater production of 3346 m 3/h (more than six times larger than the existing one). For this task, new pumping wells need to be sited and their pumping rates defined. These unknowns are determined by a genetic algorithm that minimizes a function accounting for: (1) drilling, operational and maintenance costs, (2) target discharge and minimum drawdown (i.e., minimum aquifer

  20. Titanium anchors for the repair of distal Achilles tendon ruptures: preliminary report of a new surgical technique.

    PubMed

    Maniscalco, P; Bertone, C; Bonci, E; Donelli, L; Pagliantini, L

    1998-01-01

    From January 1995 to July 1996, the authors used Mitek GIV titanium anchors to treat seven patients with acute rupture of the Achilles tendon (four men, three women; average age 52.42 years; range, 33-62 years). All subjects had a total rupture of the most distal aspect of the tendon; none had an avulsion fracture. After dissection down to the paratenon, the reinsertion site was selected and a 2 to 3-cm-long trough carved through the cortex. Three holes were drilled at a distance of 0.5 cm one from the other and 1 cm parallel and distal to the trough. The anchors were then threaded, inserted into the holes, and engaged. Surgery was completed by resection of the frayed ends, reparation of the tendon, and insertion of the terminal end into the trough. At 6 months postoperative, a modified Mandelbaum and Pavanini clinical assessment indicated five excellent and two good outcomes. There were no cases of deep of superficial wound infection or skin necrosis. Despite the small number of patients and the short follow-up period, the authors believe this technique shows promise and that in selected cases the use of titanium anchors can facilitate the task of the surgeon and enable patients to return to normal and sports activities within 5 months after surgery. PMID:9571455