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Sample records for optimized surgical techniques

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

    SciTech Connect

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

    2015-06-15

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

  2. [Optimizing surgical hand disinfection].

    PubMed

    Kampf, G; Kramer, A; Rotter, M; Widmer, A

    2006-08-01

    For more than 110 years hands of surgeons have been treated before a surgical procedure in order to reduce the bacterial density. The kind and duration of treatment, however, has changed significantly over time. Recent scientific evidence suggests a few changes with the aim to optimize both the efficacy and the dermal tolerance. Aim of this article is the presentation and discussion of new insights in surgical hand disinfection. A hand wash should be performed before the first disinfection of a day, ideally at least 10 min before the beginning of the disinfection as it has been shown that a 1 min hand wash significantly increases skin hydration for up to 10 min. The application time may be as short as 1.5 min depending on the type of hand rub. Hands and forearms should be kept wet with the hand rub for the recommended application time in any case. A specific rub-in procedure according to EN 12791 has been found to be suitable in order to avoid untreated skin areas. The alcohol-based hand rub should have a proven excellent dermal tolerance in order to ensure appropriate compliance. Considering these elements in clinical practice can have a significant impact to optimize the high quality of surgical hand disinfection for prevention of surgical site infections.

  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. Minimally invasive surgical technique for tethered surgical drains

    PubMed Central

    Hess, Shane R; Satpathy, Jibanananda; Waligora, Andrew C; Ugwu-Oju, Obinna

    2017-01-01

    A feared complication of temporary surgical drain placement is from the technical error of accidentally suturing the surgical drain into the wound. Postoperative discovery of a tethered drain can frequently necessitate return to the operating room if it cannot be successfully removed with nonoperative techniques. Formal wound exploration increases anesthesia and infection risk as well as cost and is best avoided if possible. We present a minimally invasive surgical technique that can avoid the morbidity associated with a full surgical wound exploration to remove a tethered drain when other nonoperative techniques fail.

  5. [Surgical techniques of organ transplants].

    PubMed

    Froněk, Jiří

    2015-01-01

    The list of surgical procedures of solid organ transplantations appears very interesting and colorful, even with overlap among techniques. Liver transplantation is a life-saving procedure in a majority of cases, the liver can be transplanted as a full or partial graft. The liver graft can be split for two recipients; it can also be reduced for a small recipient if splitting is not indicated. Kidney transplantation is the most common solid organ transplant procedure, the majority of kidney grafts come from brain-dead donors whereas the number of live donor transplants is increasing, also thanks to paired donation and blood group incompatible transplantation methods. The small bowel and multivisceral transplantation are rare procedures; they serve selected patients with short bowel syndrome, some patients with retroperitoneal tumors or with extensive visceral thrombosis. Solid organ transplants are well established treatment methods with good and proven outcomes. A majority of patients can return to a normal life after their transplants.

  6. 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.

  7. [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.

  8. Rhinoplasty: surface aesthetics and surgical techniques.

    PubMed

    Çakir, Bariş; Doğan, Teoman; Öreroğlu, Ali Riza; Daniel, Rollin K

    2013-03-01

    Surface aesthetics of the attractive nose are created by certain lines, shadows, and highlights, with specific proportions and breakpoints. Our evaluation of the nasal surface aesthetics is achieved using the concept of geometric polygons as aesthetic subunits, both to define the existing deformity and the aesthetic goals. Surgical techniques have been developed and modified to achieve the desired surface appearance, and those are detailed in this article. The principles of geometric polygons allow the surgeon to analyze the deformities of the nose, to define an operative plan to achieve specific goals, and to select the appropriate operative technique. These aesthetic concepts and surgical techniques were used in 257 consecutive rhinoplasties performed in the past 3 years by the principal author (B.Ç.).

  9. 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.

  10. The transcaruncular approach: surgical anatomy and technique.

    PubMed

    Goldberg, Robert A; Mancini, Ronald; Demer, Joseph L

    2007-01-01

    With a detailed understanding of the pertinent surgical anatomy, the transcaruncular approach provides safe access and excellent exposure of the medial orbit and orbital apex. We herein describe our technique of the transcaruncular approach and delineate the pertinent associated surgical anatomy via dissection, magnetic resonance imaging, and histologic examination. The isolated transcaruncular approach provides exposure of the medial orbital floor from the region of the maxilloethmoidal strut to the orbital roof area superior to the frontoethmoidal suture. When combined with an inferior fornix incision, the transcaruncular approach allows for continuous exposure from the frontozygomatic suture laterally to the frontoethmoidal suture medially. Attention to anatomical details promotes creation of an effective and safe caruncular incision. The conjunctival incision should be ample. The orbital septum should be carefully dissected from the posterior surface of the Horner muscle to minimize fat spillage, and the periosteum should be opened widely at the beginning of surgery.

  11. Optimizing Surgical Margins in Breast Conservation

    PubMed Central

    Ananthakrishnan, Preya; Balci, Fatih Levent; Crowe, Joseph P.

    2012-01-01

    Adequate surgical margins in breast-conserving surgery for breast cancer have traditionally been viewed as a predictor of local recurrence rates. There is still no consensus on what constitutes an adequate surgical margin, however it is clear that there is a trade-off between widely clear margins and acceptable cosmesis. Preoperative approaches to plan extent of resection with appropriate margins (in the setting of surgery first as well as after neoadjuvant chemotherapy,) include mammography, US, and MRI. Improvements have been made in preoperative lesion localization strategies for surgery, as well as intraoperative specimen assessment, in order to ensure complete removal of imaging findings and facilitate margin clearance. Intraoperative strategies to accurately assess tumor and cavity margins include cavity shave techniques, as well as novel technologies for margin probes. Ablative techniques, including radiofrequency ablation as well as intraoperative radiation, may be used to extend tumor-free margins without resecting additional tissue. Oncoplastic techniques allow for wider resections while maintaining cosmesis and have acceptable local recurrence rates, however often involve surgery on the contralateral breast. As systemic therapy for breast cancer continues to improve, it is unclear what the importance of surgical margins on local control rates will be in the future. PMID:23304479

  12. Post-traumatic knee stiffness: surgical techniques.

    PubMed

    Pujol, N; Boisrenoult, P; Beaufils, P

    2015-02-01

    Post-traumatic knee stiffness and loss of range of motion is a common complication of injuries to the knee area. The causes of post-traumatic knee stiffness can be divided into flexion contractures, extension contractures, and combined contractures. Post-traumatic stiffness can be due to the presence of dense intra-articular adhesions and/or fibrotic transformation of peri-articular structures. Various open and arthroscopic surgical treatments are possible. A precise diagnosis and understanding of the pathology is mandatory prior to any surgical treatment. Failure is imminent if all pathologies are not addressed correctly. From a general point of view, a flexion contracture is due to posterior adhesions and/or anterior impingement. On the other hand, extension contractures are due to anterior adhesions and/or posterior impingement. This overview will describe the different modern surgical techniques for treating post-traumatic knee stiffness. Any bony impingements must be treated before soft tissue release is performed. Intra-articular stiff knees with a loss of flexion can be treated by an anterior arthroscopic arthrolysis. Extra-articular pathology causing a flexion contracture can be treated by open or endoscopic quadriceps release. Extension contractures can be treated by arthroscopic or open posterior arthrolysis. Postoperative care (analgesia, rehabilitation) is essential to maintaining the range of motion obtained intra-operatively.

  13. Metacarpal Neck Fractures: A Review of Surgical Indications and Techniques

    PubMed Central

    Padegimas, Eric M.; Warrender, William J.; Jones, Christopher M.; Ilyas, Asif M.

    2016-01-01

    Context Hand injuries are a common emergency department presentation. Metacarpal fractures account for 40% of all hand fractures and can be seen in the setting of low or high energy trauma. The most common injury pattern is a metacarpal neck fracture. In this study, the authors aim to review the surgical indications for metacarpal neck fractures, the fixation options available along with the risk and benefits of each. Evidence Acquisition Literature review of the different treatment modalities for metacarpal neck fractures. Review focuses on surgical indications and the risks and benefits of different operative techniques. Results The indications for surgery are based on the amount of dorsal angulation of the distal fragment. The ulnar digits can tolerate greater angulation as the radial digits more easily lose grip strength. The most widely utilized fixation techniques are pinning with k-wires, dorsal plating, or intramedullary fixation. There is currently no consensus on an optimal fixation technique as surgical management has been found to have a complication rate up to 36%. Plate and screw fixation demonstrated especially high complication rates. Conclusions Metacarpal neck fractures are a common injury in young and active patients that results in substantial missed time from work. While the surgical indications are well-described, there is no consensus on the optimal treatment modality because of high complication rates. Dorsal plating has higher complication rates than closed reduction and percutaneous pinning, but is necessary in comminuted fractures. The lack of an ideal fixation construct suggests that further study of the commonly utilized techniques as well as novel techniques is necessary. PMID:27800460

  14. [Evidence-based surgical techniques for caesarean section].

    PubMed

    Aabakke, Anna J M; Secher, Niels Jørgen; Krebs, Lone

    2014-02-10

    Caesarean section (CS) is a common surgical procedure, and in Denmark 21% of deliveries is by CS. There is an increasing amount of scientific evidence to support the different surgical techniques used at CS. This article reviews the literature regarding CS techniques. There is still a lack of evidence especially about the long-term consequences of the surgical techniques.

  15. Surgical Techniques to Increase Bone Augmentation Success.

    PubMed

    Resnik, Randy R

    2015-11-01

    Oral implantology has grown into awidely acceptedand ever expanding discipline. Due to this phenomenon, more and more clinicians are offering dental implant surgery in their respective practices. As the discipline of implantology grows, the prevalence of bone grafting will become more significant. Restoring the lost hard-tissue volume to allow ideal implant placement. is crucial to decrease the Morbidity of implants and the restorations they support. Bone augmentation comprises a wide range of materials, donor sites, and surgical approaches, with new advances arriving at a staggering rate. With all of the materials and varying techniques available today, the practitioner must have a solid understanding of adjunct techniques to increase the success of bone grafting.

  16. Personalized Optimal Planning for the Surgical Correction of Metopic Craniosynostosis

    PubMed Central

    Porras, Antonio R.; Zukic, D.; Equobahrie, A.; Rogers, Gary F.; Linguraru, Marius George

    2017-01-01

    We introduce a quantitative and automated method for personalized cranial shape remodeling via fronto-orbital advancement surgery. This paper builds on an objective method for automatic quantification of malformations caused by metopic craniosynostosis in children and presents a framework for personalized interventional planning. First, skull malformations are objectively quantified using a statistical atlas of normal cranial shapes. Then, we propose a method based on poly-rigid image registration that takes into account both the clinical protocol for fronto-orbital advancement and the physical constraints in the skull to plan the creation of the optimal post-surgical shape. Our automated surgical planning technique aims to minimize cranial malformations. The method was used to calculate the optimal shape for 11 infants with age 3.8±3.0 month old presenting metopic craniosynostosis and cranial malformations. The post-surgical cranial shape provided for each patient presented a significant average malformation reduction of 49% in the frontal cranial bones, and achieved shapes whose malformations were within healthy ranges. To our knowledge, this is the first work that presents an automatic framework for an objective and personalized surgical planning for craniosynostosis treatment. PMID:28149960

  17. Endoscopic quadricepsplasty: A new surgical technique.

    PubMed

    Blanco, C E; Leon, H O; Guthrie, T B

    2001-05-01

    We present a new surgical subperiosteal endoscopic technique for the release of fibrosis of the quadriceps to the femur caused by gunshot injuries, postsurgical scarring, and fractures, that was developed at the Arthroscopy Group at Hospital Hermanos Ameijeiras in Havana, Cuba. The technique used is a proximal endoscopic subperiosteal extension of the usual arthroscopic intra-articular release of adhesions, using periosteal elevators and arthroscopic scissors placed through medial and lateral superior knee portals to release adhesions and bands of scar tissue beneath the quadriceps mechanism. The technique was used in a prospective case series of 26 male patients aged 19 to 22 years between February 1997 and March 1998 who presented with clinically and ultrasonically documented extra-articular fibrosis resulting in ankylosis of the knee in extension. Only patients who had reached a plateau in their aggressive physiotherapy program with no further progression in knee flexion for 3 months were selected. Those with joint instability, motion-limiting articular surface pathology, and muscle or neurologic injury were excluded. All patients had obtained satisfactory results at 2-year follow-up. The extra-articular release gained at final follow-up was between 30 degrees and 90 degrees of flexion in addition to that obtained at the completion of the standard intra-articular release. Complications included 1 case of deep vein thrombosis, 2 cases of scrotal edema, 5 cases of hemarthrosis, and 2 cases of reflex sympathetic dystrophy. We have found this technique useful in obtaining additional flexion and improved function in a difficult class of patients with ankylosis caused by extra-articular fibrosis of the quadriceps to the femur, allowing immediate aggressive rehabilitation and presenting a useful outpatient alternative with fewer and less severe complications than described with the classic open Thompson's quadricepsplasty.

  18. 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

  19. 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.

  20. Surgical techniques for lumbo-sacral fusion.

    PubMed

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

    2017-02-01

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

  1. Semi-automatic development of optimized surgical simulator with surgical manuals.

    PubMed

    Kuroda, Yoshihiro; Takemura, Tadamasa; Kume, Naoto; Okamoto, Kazuya; Hori, Kenta; Nakao, Megumi; Kuroda, Tomohiro; Yoshihara, Hiroyuki

    2007-01-01

    Recently, simulation platform and libraries are provided from several research groups. However, development of VR-based surgical simulator takes much effort not only for implementing simulation modules but also for setting surgical environment and choosing simulation modules. Surgical manual describes knowledge of manipulations in surgical procedure. In this study, language processing is used to extract anatomical objects and surgical manipulations in a scene from surgical manual. In addition, benchmark and LOD control of simulation modules optimize the simulation. We propose a framework of semi-automatic development of optimized simulator with surgical manuals. In the framework, SVM based machine learning is adapted in extracting surgical information and XML file was made. Simulation programs were created from XML file using a simulation library in different system configurations.

  2. 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".

  3. 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

  4. 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.

  5. Surgical management of abdominal compartment syndrome; indications and techniques

    PubMed Central

    Leppäniemi, Ari

    2009-01-01

    The indications for surgical decompression of abdominal compartment syndrome (ACS) are not clearly defined, but undoubtedly some patients benefit from it. In patients without recent abdominal incisions, it can be achieved with full-thickness laparostomy (either midline, or transverse subcostal) or through a subcutaneous linea alba fasciotomy. In spite of the improvement in physiological variables and significant decrease in IAP, however, the effects of surgical decompression on organ function and outcome are less clear. Because of the significant morbidity associated with surgical decompression and the management of the ensuing open abdomen, more research is needed to better define the appropriate indications and techniques for surgical intervention. PMID:19366442

  6. Minimally invasive surgical techniques in periodontal regeneration.

    PubMed

    Cortellini, Pierpaolo

    2012-09-01

    A review of the current scientific literature was undertaken to evaluate the efficacy of minimally invasive periodontal regenerative surgery in the treatment of periodontal defects. The impact on clinical outcomes, surgical chair-time, side effects and patient morbidity were evaluated. An electronic search of PUBMED database from January 1987 to December 2011 was undertaken on dental journals using the key-word "minimally invasive surgery". Cohort studies, retrospective studies and randomized controlled clinical trials referring to treatment of periodontal defects with at least 6 months of follow-up were selected. Quality assessment of the selected studies was done through the Strength of Recommendation Taxonomy Grading (SORT) System. Ten studies (1 retrospective, 5 cohorts and 4 RCTs) were included. All the studies consistently support the efficacy of minimally invasive surgery in the treatment of periodontal defects in terms of clinical attachment level gain, probing pocket depth reduction and minimal gingival recession. Six studies reporting on side effects and patient morbidity consistently indicate very low levels of pain and discomfort during and after surgery resulting in a reduced intake of pain-killers and very limited interference with daily activities in the post-operative period. Minimally invasive surgery might be considered a true reality in the field of periodontal regeneration. The observed clinical improvements are consistently associated with very limited morbidity to the patient during the surgical procedure as well as in the post-operative period. Minimally invasive surgery, however, cannot be applied at all cases. A stepwise decisional algorithm should support clinicians in choosing the treatment approach.

  7. 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.

  8. Invasive and minimally invasive surgical techniques for back pain conditions.

    PubMed

    Lavelle, William; Carl, Allen; Lavelle, Elizabeth Demers

    2007-12-01

    This article summarizes current issues related to invasive and minimally invasive surgical techniques for back pain conditions. It describes pain generators and explains theories about how discs fail. The article discusses techniques for treating painful sciatica, painful motion segments, and spinal stenosis. Problems related to current imaging are also presented. The article concludes with a discussion about physical therapy.

  9. Surgical Techniques Used for the Treatment of Atrial Fibrillation

    PubMed Central

    Robertson, Jason O.; Lawrance, Christopher P.; Maniar, Hersh S.; Damiano, Ralph J.

    2015-01-01

    The use of surgical lesion sets for the treatment of atrial fibrillation has been increasing, particularly in patients with complicated anatomical substrates and those undergoing concomitant surgery. Preferences in terms of lesion set, surgical approach and ablation technology vary by center. This review discusses both the surgical techniques and the outcomes for the most commonly performed procedures in the context of recent consensus guidelines. The Cox-Maze IV, pulmonary vein isolation, extended left atrial lesion sets, the hybrid approach and ganglionated plexus ablation are each reviewed in an attempt to provide insight into current clinical practice and patient selection PMID:23823731

  10. Gonioscopically Guided Nonpenetrating Cyclodialysis Cleft Repair: A Novel Surgical Technique

    PubMed Central

    Rodrigues, Ian AS; Shah, Brinda; Goyal, Saurabh

    2017-01-01

    ABSTRACT Aim We present a novel surgical technique for repair of persistent and symptomatic cyclodialysis clefts refractory to conservative or minimally invasive treatment. Background Numerous surgical techniques have been described to close cyclodialysis clefts. The current standard approach involves intraocular repair of cyclodialysis clefts underneath a full-thickness scleral flap. Technique Our technique employs intraoperative use of a direct gonioscope to guide a nonpenetrating surgical repair. Subsequently, a significantly less invasive, nonpenetrating technique utilizing a partial-thickness scleral flap can be performed that reduces potential risks associated with intraocular surgery. The direct gonioscope is also used for confirmation of adequate surgical closure of the cyclodialysis cleft prior to completion of surgery. This technique has been successfully carried out to repair traumatic chronic cyclodialysis clefts associated with hypotony in two patients. There were no significant adverse events as a result of using this technique. Conclusion The novel technique described increases the likelihood of successful and permanent repair of cyclodialysis clefts with resolution of symptoms associated with hypotony, through direct intraoperative visualization of the cleft. Clinical significance Gonioscopically guided nonpenetrating cyclodialysis cleft repair offers significant benefits over previously described techniques. Advantages of our technique include gonioscopic cleft visualization, enabling accurate localization of the area requiring repair, and subsequent confirmation of adequate closure of the cleft. Using a partial-thickness scleral flap is also less invasive and reduces risks associated with treatment of this potentially challenging complication of ocular trauma. How to cite this article Rodrigues IAS, Shah B, Goyal S, Lim S. Gonioscopically Guided Nonpenetrating Cyclodialysis Cleft Repair: A Novel Surgical Technique. J Curr Glaucoma Pract 2017

  11. Surgical technique refinements in head and neck oncologic surgery.

    PubMed

    Liu, Jeffrey C; Shah, Jatin P

    2010-06-15

    The head and neck region poses a challenging arena for oncologic surgery. Diseases and their treatment can affect a myriad of functions, including sight, hearing, taste, smell, breathing, speaking, swallowing, facial expression, and appearance. This review discusses several areas where refinements in surgical techniques have led to improved patient outcomes. This includes surgical incisions, neck lymphadenectomy, transoral laser microsurgery, minimally invasive thyroid surgery, and the use of vascularized free flaps for oromandibular reconstruction.

  12. The alexander surgical technique for the treatment of severe burns

    PubMed Central

    Gasperoni, M.; Neri, R.; Carboni, A.; Purpura, V.; Morselli, P.G.; Melandri, D.

    2016-01-01

    Summary The extensive loss of skin in burned patients is a critical clinical condition, and the choice of an effective technique to cover and protect the damaged area has always been a challenge in the surgical field. Despite its wide clinical use, there is little data in the literature on using the Alexander technique to treat severe burns, while several studies have focused on alternative approaches. The present study aims to evaluate the effectiveness of the Alexander surgical technique on 117 patients with severe burns. The characteristics of the burned patients, factors related to etiology of burns as well as adverse prognostic factors and their incidence in discharged versus deceased patients were also taken into account. Finally, a comparison is made with an alternative surgical procedure described in the literature. Our results show a satisfactory level of survival for patients with severe burns surgically treated with the Alexander technique, accounting for 63% of all clinical cases reported here. This treatment is also less expensive and more rapid than the alternative approach we compared it with. The Alexander technique is a lifesaving method for the treatment of severe burns that provides a satisfactory chance of survival at lower cost than the alternative surgical procedure examined. PMID:28289363

  13. Surgical Treatment of Epiphrenic Diverticulum: Technique and Controversies.

    PubMed

    Andolfi, Ciro; Wiesel, Ory; Fisichella, P Marco

    2016-11-01

    The goal of this article is to illustrate the current minimal invasive approaches to patients with epiphrenic diverticulum in terms of preoperative evaluation, surgical technique, and outcomes. Two techniques will be presented: a laparoscopic and a video-assisted thoracic repair. Indications for each technique will be discussed as well as proper patient selection and management. Current controversies in the treatment of patients with this rare disease will be addressed.

  14. 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

  15. 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

  16. Surgical technique for revision surgery of cervical artificial disc replacements.

    PubMed

    Onken, Julia; Meyer, Bernhard; Vajkoczy, Peter

    2017-01-01

    OBJECTIVE Cervical artificial disc replacement (C-ADR) is a widely used procedure with low risk at implantation. Few cases have been reported about the surgical techniques of C-ADR revision. The authors describe their surgical experience with the explantation of a Galileo C-ADR. METHODS Revision surgery was performed in a 58-year-old patient. Patient positioning and surgical opening techniques were performed as appropriate for anterior cervical decompression. RESULTS Revision surgery via the initial anterior approach was successful following an atraumatic removal of the implant. Fusion of the C5-6 segment was performed without complications. CONCLUSIONS In general, the authors observed recurrent nerve palsy and malpositioning of the revised implant in C-ADR revision surgery. Problems with implant removal did not occur because the fusion rate was low due to the short time between initial surgery and C-ADR revision surgery. The video can be found here: https://youtu.be/32CUEDquinc .

  17. 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)

  18. The posterolateral corner: surgical approach and technique overview.

    PubMed

    Dickens, Jonathan F; Kilcoyne, Kelly; Kluk, Matthew; Rue, John-Paul

    2011-09-01

    Injuries to the posterolateral corner (PLC) of the knee can lead to profound knee instability, especially when combined with anterior cruciate or posterior cruciate ligament injury. With increased recognition of this injury, as well as improved understanding of the pathoanatomy, surgical treatment of these injuries has evolved in favor of acute treatment including reconstructive techniques to minimize recurrent laxity and allow for early rehabilitation. This article describes the approach to the PLC and the technique for figure of 8 reconstruction.

  19. Cartilage repair: synthetics and scaffolds: basic science, surgical techniques, and clinical outcomes.

    PubMed

    Kerker, Jordan T; Leo, Andrew J; Sgaglione, Nicholas A

    2008-12-01

    Symptomatic articular cartilage lesions have gained attention and clinical interest in recent years and can be difficult to treat. Historically, various biologic surgical treatment options have yielded inconsistent results because of the inferior biomechanical properties associated with a variable healing response. Improving technology and surgical advances has generated considerable research in cartilage resurfacing and optimizing hyaline tissue restoration. Biologic innovation and tissue engineering in cartilage repair have used matrix scaffolds, autologous and allogenic chondrocytes, cartilage grafts, growth factors, stem cells, and genetic engineering. Numerous evolving technologies and surgical approaches have been introduced into the clinical setting. This review will discuss the basic science, surgical techniques, and clinical outcomes of novel synthetic materials and scaffolds for articular cartilage repair.

  20. Optimization and surgical design for applications in pediatric cardiology

    NASA Astrophysics Data System (ADS)

    Marsden, Alison; Bernstein, Adam; Taylor, Charles; Feinstein, Jeffrey

    2007-11-01

    The coupling of shape optimization to cardiovascular blood flow simulations has potential to improve the design of current surgeries and to eventually allow for optimization of surgical designs for individual patients. This is particularly true in pediatric cardiology, where geometries vary dramatically between patients, and unusual geometries can lead to unfavorable hemodynamic conditions. Interfacing shape optimization to three-dimensional, time-dependent fluid mechanics problems is particularly challenging because of the large computational cost and the difficulty in computing objective function gradients. In this work a derivative-free optimization algorithm is coupled to a three-dimensional Navier-Stokes solver that has been tailored for cardiovascular applications. The optimization code employs mesh adaptive direct search in conjunction with a Kriging surrogate. This framework is successfully demonstrated on several geometries representative of cardiovascular surgical applications. We will discuss issues of cost function choice for surgical applications, including energy loss and wall shear stress distribution. In particular, we will discuss the creation of new designs for the Fontan procedure, a surgery done in pediatric cardiology to treat single ventricle heart defects.

  1. 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.

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

    PubMed

    Renzulli, P; Candinas, D

    2007-09-01

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

  3. Pedunculopontine Nucleus Region Deep Brain Stimulation in Parkinson Disease: Surgical Techniques, Side Effects, and Postoperative Imaging

    PubMed Central

    Hamani, Clement; Lozano, Andres M.; Mazzone, Paolo A.M.; Moro, Elena; Hutchison, William; Silburn, Peter A.; Zrinzo, Ludvic; Alam, Mesbah; Goetz, Laurent; Pereira, Erlick; Rughani, Anand; Thevathasan, Wesley; Aziz, Tipu; Bloem, Bastiaan R.; Brown, Peter; Chabardes, Stephan; Coyne, Terry; Foote, Kelly; Garcia-Rill, Edgar; Hirsch, Etienne C.; Okun, Michael S.; Krauss, Joachim K.

    2017-01-01

    The pedunculopontine nucleus (PPN) region has received considerable attention in clinical studies as a target for deep brain stimulation (DBS) in Parkinson disease. These studies have yielded variable results with an overall impression of improvement in falls and freezing in many but not all patients treated. We evaluated the available data on the surgical anatomy and terminology of the PPN region in a companion paper. Here we focus on issues concerning surgical technique, imaging, and early side effects of surgery. The aim of this paper was to gain more insight into the reasoning for choosing specific techniques and to discuss short-comings of available studies. Our data demonstrate the wide range in almost all fields which were investigated. There are a number of important challenges to be resolved, such as identification of the optimal target, the choice of the surgical approach to optimize electrode placement, the impact on the outcome of specific surgical techniques, the reliability of intraoperative confirmation of the target, and methodological differences in postoperative validation of the electrode position. There is considerable variability both within and across groups, the overall experience with PPN DBS is still limited, and there is a lack of controlled trials. Despite these challenges, the procedure seems to provide benefit to selected patients and appears to be relatively safe. One important limitation in comparing studies from different centers and analyzing outcomes is the great variability in targeting and surgical techniques, as shown in our paper. The challenges we identified will be of relevance when designing future studies to better address several controversial issues. We hope that the data we accumulated may facilitate the development of surgical protocols for PPN DBS. PMID:27728909

  4. Modified Surgical Techniques for Managing Intraoperative Floppy Iris Syndrome

    PubMed Central

    Charukamnoetkanok, Puwat

    2016-01-01

    Purpose. To report a modified surgical strategy in the management of intraoperative floppy iris syndrome-associated iris prolapse. Methods. Prolapsed iris is left as is and a new corneal incision near the original wound but at a different site is created. Depending on the location of the original incision and the surgeon's preference, this additional incision can be used as a new port for phacoemulsification tip or can be the new site for the iris to securely prolapse, allowing for the surgery to proceed safely. Results. We present 2 cases of iris prolapse and inadequate pupil dilation in patients with IFIS. Along with our modified technique, additional iris retractors were placed to increase the workspace for the phacoemulsification tip. The cataract surgery was performed successfully without further complications in both cases. Conclusion. This surgical technique could be an adjunct to allow the surgeons to expand the armamentarium for the management of IFIS-associated iris prolapse. PMID:27999697

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

    PubMed

    Zelle, Boris A; Boni, Guilherme

    2015-01-01

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

  6. Hemorrhage after tonsillectomy: does the surgical technique really matter?

    PubMed

    Gysin, Claudine; Dulguerov, Pavel

    2013-01-01

    A thorough review of the publications on surgical techniques used for tonsillectomy is provided, emphasizing randomized studies and meta-analysis. In the assessment of the data it is important to clearly define and categorize the types of posttonsillectomy bleeding (PTB), as well as the various factors that have been associated with increased PTB. In recent audits of a large number of tonsillectomies, the PTB rates seem to concur: 1% early and 2.5% delayed PTB; 10% anamnestic, 2% objective, and 2% re-operation PTB. Objective PTB rates beyond 10% should require an audit. The bipolar technique seems associated with the least early PTB, while the cold technique is associated with the least delayed PTB. Because of the lack of large well-conducted randomized trials, it is difficult to conclude which technique is the best. With electrocautery techniques, the current power should be adjusted to the minimal level providing hemostasis. Surgical techniques for tonsillectomy that should probably be abandoned include monopolar electrocautery, Coblation, various lasers, and the harmonic scalpel. Vessel-sealing systems might hold promise and deserve further evaluation. Tonsillotomy might be associated with less postoperative pain, but the hemorrhagic advantage in randomized studies is not obvious. Tonsil regrowth rates and efficacy to treat obstruction need also further evaluation.

  7. Surgical Treatment of Tennis Elbow; Minimal Incision Technique

    PubMed Central

    Amroodi, Morteza Nakhaei; Mahmuudi, Ali; Salariyeh, Mostafa; Amiri, Arash

    2016-01-01

    Background: When non-operative treatment of tennis elbow fails; a surgical procedure can be performed to improve the associated symptoms. Different surgical techniques for treatment of lateral epicondylitis are prescribed. The purpose of this study was to evaluate the clinical outcomes of surgical treatment for tennis elbow based on small incision techniques. Methods: This technique was performed on 24 consecutive patients between June 2011 and July 2013. Outcomes were assessed using the Patient-Rated Tennis Elbow Evaluation (PRTEE), Nirschl’s staging system and visual analog scale (VAS) for pain and satisfaction criteria. Results: There were 15 female and 9 male patients in the study. The mean duration of symptoms before surgery was 3.7 years. The average duration of follow-up was 34.8 months. The post-operative outcome was good to excellent in most patients. The mean VAS score improved from 7.2 to 3.5 points. The total PRTEE improved from 68.7 to 15.8 points. Conclusion: This procedure provides a low complication rate which is associated with a high rate of patient satisfaction. Therefore, we suggest this option after failed conservative management of tennis elbow. PMID:27847851

  8. An artificial system for selecting the optimal surgical team.

    PubMed

    Saberi, Nahid; Mahvash, Mohsen; Zenati, Marco

    2015-01-01

    We introduce an intelligent system to optimize a team composition based on the team's historical outcomes and apply this system to compose a surgical team. The system relies on a record of the procedures performed in the past. The optimal team composition is the one with the lowest probability of unfavorable outcome. We use the theory of probability and the inclusion exclusion principle to model the probability of team outcome for a given composition. A probability value is assigned to each person of database and the probability of a team composition is calculated from them. The model allows to determine the probability of all possible team compositions even if there is no recoded procedure for some team compositions. From an analytical perspective, assembling an optimal team is equivalent to minimizing the overlap of team members who have a recurring tendency to be involved with procedures of unfavorable results. A conceptual example shows the accuracy of the proposed system on obtaining the optimal team.

  9. Surgical ablation for atrial fibrillation: techniques, indications, and results

    PubMed Central

    Lawrance, Christopher P.; Henn, Matthew C.; Damiano, Ralph J.

    2015-01-01

    Purpose of review The aim of this review is to focus specifically on the indications, evolution of technique, and results of surgical ablation for atrial fibrillation. Recent findings With the introduction of the Cox-Maze IV procedure utilizing bipolar radiofrequency ablation and cryoablation, long-term studies have demonstrated a significant decrease in aortic cross-clamp times and major complications with a comparable rate of restoration of sinus rhythm. New hybrid approaches utilizing both catheter-based ablation and minimally invasive surgical approaches have been developed, but have not been standardized. Early studies have demonstrated reasonable success rates of hybrid procedures, with advantages that include confirmation of conduction block, decreased surgical morbidity, and possibly reduced morbidity. However, hybrid approaches have the disadvantage of significantly increased operative times. Summary The Cox-Maze IV is currently the gold standard for surgical treatment of atrial fibrillation. New hybrid approaches have potential advantages with promising early results, but a standard lesion set, improvement in operative times, and long-term results still need to be evaluated. PMID:25389650

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

    PubMed

    Crawshaw, Alison; Williams, Julia; Woodhouse, Fran

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

  11. 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

  12. Surgical technique for allogeneic uterus transplantation in macaques

    PubMed Central

    Obara, Hideaki; Kisu, Iori; Kato, Yojiro; Yamada, Yohei; Matsubara, Kentaro; Emoto, Katsura; Adachi, Masataka; Matoba, Yusuke; Umene, Kiyoko; Nogami, Yuya; Banno, Kouji; Tsuchiya, Hideaki; Itagaki, Iori; Kawamoto, Ikuo; Nakagawa, Takahiro; Ishigaki, Hirohito; Itoh, Yasushi; Ogasawara, Kazumasa; Saiki, Yoko; Sato, Shin-ichi; Nakagawa, Kenshi; Shiina, Takashi; Aoki, Daisuke; Kitagawa, Yuko

    2016-01-01

    No study has reported an animal model of uterus transplantation (UTx) using cynomolgus macaques. We aimed to establish a surgical technique of allogeneic UTx assuming the recovery of a uterus from a deceased donor in cynomolgus macaques. Four allogeneic UTxs were performed in female cynomolgus macaques. Donor surgeries comprised en bloc recovery of organs with iliac vessels on both sides, and/or abdominal aorta/vena cava after sufficient perfusion from one femoral artery or external iliac artery. Before perfusion, 150 mL of whole blood was obtained from the donor for subsequent blood transfusion to the recipient. Four uterine grafts were orthotopically transplanted to recipients. End-to-side anastomosis was performed to the iliac vessels on one side in case 1 and iliac vessels on both sides in case 2; aorto-aorto/cavo-caval anastomosis was performed in cases 3 and 4. Arterial blood flow of the uterine grafts was determined by intraoperative indocyanine green (ICG) angiography. ICG angiography results showed sufficient blood flow to all uterine grafts, and anaemia did not progress. Under appropriate immune suppression, all recipients survived for more than 90 days post-transplantation, without any surgical complications. We describe a surgical technique for allogeneic UTx in cynomolgus macaques. PMID:27786258

  13. Ahmed glaucoma valve implant: surgical technique and complications

    PubMed Central

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

    2017-01-01

    Implantation of Ahmed glaucoma valve is an effective surgical technique to reduce intraocular pressure in patients affected with glaucoma. While in the past, the use of this device was reserved to glaucoma refractory to multiple filtration surgical procedures, up-to-date mounting experience has encouraged its use also as a primary surgery for selected cases. Implantation of Ahmed glaucoma valve can be challenging for the surgeon, especially in patients who already underwent previous multiple surgeries. Several tips have to be acquired by the surgeon, and a long learning curve is always needed. Although the valve mechanism embedded in the Ahmed glaucoma valve decreases the risk of postoperative hypotony-related complications, it does not avoid the need of a careful follow-up. Complications related to this type of surgery include early and late postoperative hypotony, excessive capsule fibrosis around the plate, erosion of the tube or plate edge, and very rarely infection. The aim of this review is to describe surgical technique for Ahmed glaucoma valve implantation and to report related complications. PMID:28255226

  14. 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.

  15. [Surgical reconstruction of maxillary defects using computer-assisted techniques].

    PubMed

    Zhang, W B; Yu, Y; Wang, Y; Liu, X J; Mao, C; Guo, C B; Yu, G Y; Peng, X

    2017-02-18

    The maxilla is the most important bony support of the mid-face skeleton and is critical for both esthetics and function. Maxillary defects, resulting from tumor resection, can cause severe functional and cosmetic deformities. Furthermore, maxillary reconstruction presents a great challenge for oral and maxillofacial surgeons. Nowadays, vascularized composite bone flap transfer has been widely used for functional maxillary reconstruction. In the last decade, we have performed a comprehensive research on functional maxillary reconstruction with free fibula flap and reported excellent functional and acceptable esthetic results. However, this experience based clinical procedure still remainssome problems in accuracy and efficiency. In recent years, computer assisted techniques are now widely used in oral and maxillofacial surgery. We have performed a series of study on maxillary reconstruction with computer assisted techniques. The computer assisted techniques used for maxillary reconstruction mainly include: (1) Three dimensional (3D) reconstruction and tumor mapping: providing a 3D view of maxillary tumor and adjacent structures and helping to make the diagnosis of maxillary tumor accurate and objective; (2) Virtual planning: simulating tumor resection and maxillectomy as well as fibula reconstruction on the computer, so that to make an ideal surgical plan; (3) 3D printing: producing a 3D stereo model for prebending individualized titanium mesh and also providing template or cutting guide for the surgery; (4) Surgical navigation: the bridge between virtual plan and real surgery, confirming the virtual plan during the surgery and guarantee the accuracy; (5) Computer assisted analyzing and evaluating: making a quantitative and objective of the final result and evaluating the outcome. We also performed a series of studies to evaluate the application of computer assisted techniques used for maxillary reconstruction, including: (1) 3D tumor mapping technique for accurate

  16. Radio electric tissue optimization in the treatment of surgical wounds

    PubMed Central

    Castagna, Alessandro; Fontani, Vania; Rinaldi, Salvatore; Mannu, Piero

    2011-01-01

    Purpose To report preliminary results with the tissue optimization (TO) treatment with a radio electric asymmetric conveyer (REAC) in promoting the repair of surgical wounds. Patients and methods Two subjects, a 54-year-old male with a tear bruise on the upper third of the leg and a 19-year-old female with a stab wound to the hand, were treated with 12 REAC-TO treatment sessions. Results In both patients, the wounds showed shorter healing time compared with the time usually required for similar wounds, and good repair quality. Conclusion REAC device with its specific treatment protocols may be an alternative therapy for wound healing. PMID:21931498

  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. Orthodontic microsurgery: a new surgically guided technique for dental movement.

    PubMed

    Vercellotti, Tomaso; Podesta, Andrea

    2007-08-01

    Eight patients with malocclusions were treated with a new orthodontic-surgical technique that reduces the duration of treatment compared to conventional techniques. The monocortical tooth dislocation and ligament distraction (MTDLD) technique combines two different dental movements that work separately but simultaneously on opposite root surfaces. On the root surface corresponding to the direction of movement, vertical and horizontal microsurgical corticotomies are performed around each tooth root with a piezosurgical microsaw to eliminate cortical bone resistance. The immediate application of strong biomechanical forces produces rapid dislocation of the root and the cortical bone together. On the root surface opposite the direction of movement, the force of dislocation produces rapid distraction of ligament fibers. During the osteogenic process that follows, application of normal orthodontic biomechanics achieves the final tooth movement. All eight patients underwent periodontal and radiologic examinations for more than 1 year after treatment. No periodontal defects were observed in any of the patients, including one with a severe malocclusion and a thin periodontal tissue biotype. Compared to traditional orthodontic therapy, the average treatment time with the MTDLD technique in the mandible and maxilla was reduced by 60% and 70%, respectively.

  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. 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.

  1. Total hip replacement for hip fracture: Surgical techniques and concepts.

    PubMed

    Coomber, Ross; Porteous, Matthew; Hubble, Matthew J W; Parker, Martyn J

    2016-10-01

    When treating a hip fracture with a total hip replacement (THR) the surgical technique may differ in a number of aspects in comparison to elective arthroplasty. The hip fracture patient is more likely to have poor bone stock secondary to osteoporosis, be older, have a greater number of co-morbidities, and have had limited peri-operative work-up. These factors lead to a higher risk of complications, morbidity and perioperative mortality. Consideration should be made to performing the THR in a laminar flow theatre, by a surgeon experienced in total hip arthroplasty, using an anterolateral approach, cementing the implant in place, using a large head size and with repair of the joint capsule. Combined Ortho-geriatric care is recommended with similar post-operative rehabilitation to elective THR patients but with less expectation of short length of stay and consideration for fracture prevention measures.

  2. Treatment of keloid formation following syndactyly division: surgical technique.

    PubMed

    Kong, Bong Young; Baek, Goo Hyun; Gong, Hyun Sik

    2012-01-01

    A strong association has been reported between keloid formation after syndactyly reconstruction and primary digital enlargement, and methotrexate (MTX) treatment has been shown to produce promising results in a few reported cases. However, detailed surgical technique for revision of keloid formation after syndactyly division has not been well described, and there is still no standard treatment protocol regarding use of MTX in such cases. In this paper, we describe the technical details of keloid excision and full thickness skin grafting followed by MTX medication for the treatment of massive keloid formation after syndactyly division. We also describe a case of unsuccessful use of MTX, and our experience of its prophylactic use for a patient with syndactyly with primary digital enlargement.

  3. Technique and staining optimization leucoconcentration.

    PubMed

    Pierrez, J; Guerci, A; Guerci, O

    1987-09-01

    In cytometric clinical application, it is important to obtain cell suspensions rapidly with as little cytological alteration as possible. A procedure has been achieved to prepare cell suspensions for flow cytometric analysis. The leucoconcentration technique, first described by Herbeuval for cytologic analysis, has been modified to be applied in cytometry. This technique involves Saponin lysis of red cells of peripheral blood or bone marrow samples that have been previously fixed with picric acid alcohol solution. Cells in suspension are not shifted and tinctorial affinity is not modified. Then cells have been stained with Mithramycin. Each parameter defined by Crissman has been analyzed to define the best staining conditions. The availability of Leucoconcentration with Mithramycin-DNA-staining permits determination of cell cycle with a fine resolution.

  4. 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

  5. Surgical technique for repair of complex anterior skull base defects

    PubMed Central

    Reinard, Kevin; Basheer, Azam; Jones, Lamont; Standring, Robert; Lee, Ian; Rock, Jack

    2015-01-01

    Background: Modern microsurgical techniques enable en bloc resection of complex skull base tumors. Anterior cranial base surgery, particularly, has been associated with a high rate of postoperative cerebrospinal fluid (CSF) leak, meningitis, intracranial abscess, and pneumocephalus. We introduce simple modifications to already existing surgical strategies designed to minimize the incidence of postoperative CSF leak and associated morbidity and mortality. Methods: Medical records from 1995 to 2013 were reviewed in accordance with the Institutional Review Board. We identified 21 patients who underwent operations for repair of large anterior skull base defects following removal of sinonasal or intracranial pathology using standard craniofacial procedures. Patient charts were screened for CSF leak, meningitis, or intracranial abscess formation. Results: A total of 15 male and 6 female patients with an age range of 26–89 years were included. All patients were managed with the same operative technique for reconstruction of the frontal dura and skull base defect. Spinal drainage was used intraoperatively in all cases but the lumbar drain was removed at the end of each case in all patients. Only one patient required re-operation for repair of persistent CSF leak. None of the patients developed meningitis or intracranial abscess. There were no perioperative mortalities. Median follow-up was 10 months. Conclusion: The layered reconstruction of large anterior cranial fossa defects resulted in postoperative CSF leak in only 5% of the patients and represents a simple and effective closure option for skull base surgeons. PMID:25722926

  6. Through Knee Amputation: Technique Modifications and Surgical Outcomes

    PubMed Central

    Albino, Frank P; Seidel, Rachel; Brown, Benjamin J; Crone, Charles G

    2014-01-01

    Background Knee disarticulations (KD) are most commonly employed following trauma or tumor resection but represent less than 2% of all lower extremity amputations performed in the United States annually. KDs provide enhanced proprioception, a long lever arm, preservation of adductor muscle insertion, decreased metabolic cost of ambulation, and an end weight-bearing stump. The role for KDs in the setting of arterial insufficiency or overwhelming infection is less clear. The purpose of this study is to describe technique modifications and report surgical outcomes following KDs at a high-volume Limb Salvage Center. Methods A retrospective study of medical records for all patients who underwent a through-knee amputation performed by the senior author (C.E.A.) between 2004 and 2012 was completed. Medical records were reviewed to collect demographic, operative, and postoperative information for each of the patients identified. Results Between 2004 and 2012, 46 through-knee amputations for 41 patients were performed. The mean patient age was 68 and indications for surgery included infection (56%), arterial thrombosis (35%), and trauma (9%). Postoperative complications included superficial cellulitis (13%), soft tissue infection (4%), and flap ischemia (4%) necessitating one case of surgical debridement (4%) and four trans-femoral amputations (9%). 9 (22%) patients went on to ambulate. Postoperative ambulation was greatest in the traumatic cohort and for patients less than 50 years of age, P<0.05. Alternatively, diabetes mellitus and infection reduced the likelihood of postoperative ambulation, P<0.01. Conclusions Knee disarticulations are a safe and effective alternative to other lower extremity amputations when clinically feasible. For patient unlikely to ambulate, a through-knee amputation maximizes ease of transfers, promotes mobility by providing a counterbalance, and eliminates the potential for knee flexion contracture with subsequent skin breakdown. PMID:25276650

  7. Optimal Multiobjective Design of Digital Filters Using Taguchi Optimization Technique

    NASA Astrophysics Data System (ADS)

    Ouadi, Abderrahmane; Bentarzi, Hamid; Recioui, Abdelmadjid

    2014-01-01

    The multiobjective design of digital filters using the powerful Taguchi optimization technique is considered in this paper. This relatively new optimization tool has been recently introduced to the field of engineering and is based on orthogonal arrays. 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 Taguchi optimization technique produced filters that fulfill the desired characteristics and are of practical use.

  8. A survey of compiler optimization techniques

    NASA Technical Reports Server (NTRS)

    Schneck, P. B.

    1972-01-01

    Major optimization techniques of compilers are described and grouped into three categories: machine dependent, architecture dependent, and architecture independent. Machine-dependent optimizations tend to be local and are performed upon short spans of generated code by using particular properties of an instruction set to reduce the time or space required by a program. Architecture-dependent optimizations are global and are performed while generating code. These optimizations consider the structure of a computer, but not its detailed instruction set. Architecture independent optimizations are also global but are based on analysis of the program flow graph and the dependencies among statements of source program. A conceptual review of a universal optimizer that performs architecture-independent optimizations at source-code level is also presented.

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

    PubMed

    Geiger, James D; Hirschl, Ronald B

    2015-06-01

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

  10. Surgical technique of orthotopic liver transplantation in rats: the Kamada technique and a new splint technique for hepatic artery reconstruction.

    PubMed

    Ishii, Eiichi; Shimizu, Akira; Takahashi, Mikiko; Terasaki, Mika; Kunugi, Shinobu; Nagasaka, Shinya; Terasaki, Yasuhiro; Ohashi, Ryuji; Masuda, Yukinari; Fukuda, Yuh

    2013-01-01

    Orthotopic liver transplantation (OLT) in rats is technically feasible and useful for the assessment of clinical liver transplantation and analysis of inflammatory liver diseases. OLT in rats was pioneered by Lee et al. in 1973 using hand-suture techniques of all vessels. This model has not been widely used due to the long operative time and technical demand. The cuff method was introduced by Kamada in 1979, and today, the Kamada technique is the one most commonly used worldwide. However, this technique does not include hepatic artery reconstruction, although this procedure is routinely performed in clinical transplantation. Nevertheless, several techniques for hepatic artery reconstruction in rat OLT have been reported recently, and our group also developed a simple splint technique from recipient right renal artery to donor celiac axis bearing the hepatic artery. In the present article, we describe the Kamada technique, as a standard surgical method for rat OLT. In addition, we also describe our splint technique for hepatic artery reconstruction. Then, we compare the features of Kamada technique and our splint technique for hepatic artery reconstruction and all other surgical techniques currently in use for rat OLT. The widespread use of the rat OLT model should help to provide full assessment of transplant immunology and the mechanism and treatment of inflammatory liver diseases.

  11. 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

  12. Robotic-assisted mitral valve repair: surgical technique.

    PubMed

    Algarni, Khaled D; Suri, Rakesh M; Daly, Richard C

    2014-01-01

    Robotic-assisted mitral valve repair represents the least invasive surgical approach currently available for anatomical mitral valve repair in patients with myxomatous mitral valve disease. Standard mitral valve repair techniques utilized during conventional sternotomy/right thoracotomy are exactly replicated with the robotic instrumentation through 1-2 cm port-like incisions with superior 3D visualization. This is performed on cardiopulmonary bypass by peripheral cannulation of the femoral vessels/right internal jugular vein. The ascending aorta is occluded with a transthoracic aortic cross-clamp. Antegrade cardioplegia is delivered centrally into the aortic root through a cardioplegia vent catheter. By replicating conventional mitral valve repair done via an open sternotomy approach, the quality of mitral valve repair is ensured while providing the patients with advantages of less invasive surgery including shorter hospital stay, rapid recovery and return to normal activities, less blood transfusion, superior cosmesis and complete elimination of sternotomy-related morbidities such as deep sternal wound infection and sternal dehiscence. We reviewed the first consecutive 200 patients undergoing robotic mitral valve repair at Mayo Clinic Rochester between 24 January 2008 and 28 January 2011. Successful mitral valve repair was completed in all patients. There were no early (30-day) deaths. One patient suffered a stroke (0.5%). One patient required reoperation for bleeding (0.5%). Two patients (1%) required reoperation for recurrent mitral regurgitation. Twelve patients (6%) required transfusion of allogeneic blood products. We have noted a significant reduction in operative times and resource utilization over time.

  13. 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.

  14. 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.

  15. 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

  16. Non-surgical treatment of early breast cancer: techniques on the way.

    PubMed

    Hamza, Alaa; Elrefaey, Shymaa

    2014-08-01

    Trials are still on the way to evaluate different non-surgical techniques to treat early breast cancer with achieving maximum oncological control and aesthetic outcome. Also these techniques can help old patients to bypass surgical and radiation complications and facilitate the treatment of early breast cancer with minimum side effects.

  17. Shape optimization techniques for musical instrument design

    NASA Astrophysics Data System (ADS)

    Henrique, Luis; Antunes, Jose; Carvalho, Joao S.

    2002-11-01

    The design of musical instruments is still mostly based on empirical knowledge and costly experimentation. One interesting improvement is the shape optimization of resonating components, given a number of constraints (allowed parameter ranges, shape smoothness, etc.), so that vibrations occur at specified modal frequencies. Each admissible geometrical configuration generates an error between computed eigenfrequencies and the target set. Typically, error surfaces present many local minima, corresponding to suboptimal designs. This difficulty can be overcome using global optimization techniques, such as simulated annealing. However these methods are greedy, concerning the number of function evaluations required. Thus, the computational effort can be unacceptable if complex problems, such as bell optimization, are tackled. Those issues are addressed in this paper, and a method for improving optimization procedures is proposed. Instead of using the local geometric parameters as searched variables, the system geometry is modeled in terms of truncated series of orthogonal space-funcitons, and optimization is performed on their amplitude coefficients. Fourier series and orthogonal polynomials are typical such functions. This technique reduces considerably the number of searched variables, and has a potential for significant computational savings in complex problems. It is illustrated by optimizing the shapes of both current and uncommon marimba bars.

  18. 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.

  19. 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.

  20. A New Surgical Technique for Closure of Pilonidal Sinus Defects: Triangular Closure Technique

    PubMed Central

    Mutaf, Mehmet; Temel, Metin; Koç, Mustafa Nihat

    2017-01-01

    Background We present a clinical experience with a new local flap procedure, namely the triangular closure technique, for reconstruction of sacrococcygeal skin defects resulting from excision of the pilonidal sinus. Material/Methods In this technique, the defect is surgically converted to a triangle in shape. Then, the triangular defect is closed by transposition of 2 skin flaps designed in an unequal z-plasty manner. Over 6 years, this technique has been used for closure of defects of chronic pilonidal sinus disease in 27 patients (6 females, 21 males). The size of the defect ranged between 3.5 cm and 12 cm in dimension. Results A tension-free defect closure was obtained in all patients. All flaps except one healed with no complications. A mean follow-up of 3.62±1.77 months revealed aesthetically and functionally acceptable results with the obliteration of the natal cleft in all patients. No recurrence was observed in the follow-up period. Conclusions The triangular closure technique was found to be a useful technique for the treatment of pilonidal sinus with favorable results regarding the time before return to work. PMID:28238003

  1. 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.

  2. Comparison of surgical techniques in the treatment of laryngeal polypoid degeneration.

    PubMed

    Lumpkin, S M; Bishop, S G; Bennett, S

    1987-01-01

    Surgical excision has been the accepted treatment of laryngeal polypoid degeneration, or chronic polypoid corditis. We report on 29 women with polypoid degeneration who received one of three surgical treatments: vocal fold stripping, carbon dioxide laser obliteration, or the Hirano technique. The duration of postoperative dysphonia was longest with the laser removal and shortest with the Hirano technique. A combination of vocal hygiene management and the Hirano technique of removal provided the most efficacious treatment.

  3. A Novel Surgical Technique to Correct Intrareolar Polythelia

    PubMed Central

    Cherubino, Mario; Pellegatta, Igor; Frigo, Claudia; Scamoni, Stefano; Taibi, Dominic; Maggiulli, Francesca; Valdatta, Luigi

    2014-01-01

    Polythelia is a rare congenital malformation that occurs in 1–2% of the population. Intra-areolar polythelia is the presence of one or more supernumerary nipples located within the areola. This is extremely rare. This article presents 3 cases of intra-areolar polythelia treated at our Department. These cases did not present other associated malformation. Surgical correction was performed for psychological and cosmetic reasons using advancement flaps. The aesthetic and functional results were satisfactory.

  4. Surgical Treatment of Corneal Ectasia with Motowa's Trephine and Selective Suturing Technique

    PubMed Central

    Al-Motowa, Saeed; Al-Harby, Mosa

    2016-01-01

    A 40-year-old male presented with bilateral ectasia, contact lens intolerance, and astigmatism >10 D in both eyes. The patient had end-stage pellucid marginal degeneration that warranted surgical treatment. We present a unique surgical technique to stabilize the cornea, minimize astigmatism, improve vision and corneal status, and avoid penetrating keratoplasty. PMID:27994396

  5. Optimization of printing techniques for electrochemical biosensors

    NASA Astrophysics Data System (ADS)

    Zainuddin, Ahmad Anwar; Mansor, Ahmad Fairuzabadi Mohd; Rahim, Rosminazuin Ab; Nordin, Anis Nurashikin

    2017-03-01

    Electrochemical biosensors show great promise for point-of-care applications due to their low cost, portability and compatibility with microfluidics. The miniature size of these sensors provides advantages in terms of sensitivity, specificity and allows them to be mass produced in arrays. The most reliable fabrication technique for these sensors is lithography followed by metal deposition using sputtering or chemical vapor deposition techniques. This technique which is usually done in the cleanroom requires expensive masking followed by deposition. Recently, cheaper printing techniques such as screen-printing and ink-jet printing have become popular due to its low cost, ease of fabrication and mask-less method. In this paper, two different printing techniques namely inkjet and screen printing are demonstrated for an electrochemical biosensor. For ink-jet printing technique, optimization of key printing parameters, such as pulse voltages, drop spacing and waveform setting, in-house temperature and cure annealing for obtaining the high quality droplets, are discussed. These factors are compared with screen-printing parameters such as mesh size, emulsion thickness, minimum spacing of lines and curing times. The reliability and reproducibility of the sensors are evaluated using scotch tape test, resistivity and profile-meter measurements. It was found that inkjet printing is superior because it is mask-less, has minimum resolution of 100 µm compared to 200 µm for screen printing and higher reproducibility rate of 90% compared to 78% for screen printing.

  6. 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

  7. [Merle D'Aubigne's oblique proximal femoral osteotomy. Surgical technique].

    PubMed

    López Sosa, Francisco H; Valentín-Guerrero, Santiago; Miranda-López, Eduardo

    2008-01-01

    Proximal femoral osteotomy with the technique described by Merle D'AubignC and Valliant was used in the treatment of adult patients with osteoarthritis or idiopathic avascular necrosis. Dr. Antonio Flores applied this technique to children with subluxation and acetabular dysplasia, identified with exaggerated anteversion and valgus of the proximal femur. He reported correction of the deformity in 75% of patients. The purpose of this paper is to describe the technique, its indications and complications.

  8. Optimal piezoelectric switching technique for vibration damping

    NASA Astrophysics Data System (ADS)

    Neubauer, Marcus; Oleskiewicz, Robert

    2007-04-01

    This paper describes piezoelectric switching techniques for vibration damping. The dynamical behaviour of a piezoceramics connected to a switching LR shunt and the dissipated energy are obtained using a fundamental piezoelectric model. All calculations are performed in a normalized way and highlight the influence of the electromechanical coupling coefficient of the piezoceramics and the shunt parameters. For the first time, a precise result for the dynamics of a shunted piezoceramics is derived. The analytic results are used to determine the optimal switching sequence and external branch parameters in order to maximize the damping performance. The results are validated by measurements of a clamped beam.

  9. 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.

  10. Key discoveries in the evolution of surgical techniques.

    PubMed

    The BJN reported on a paper given by the superintendent of the General Hospital, Kingston, Ontario. It seems that there were three key discoveries in the history of surgery, which of course are still relevant today. The first was Ambrose Pare, who was responsible for introducing the ligature and replacing the 'red hot knife and cautery'. Ligature is the term given to the length of thread or other material, which was used in the surgical process of tying off a duct or a blood vessel to stop bleeding. Cautery or cauterization was the application of a heated instrument, such as a knife, in those days to destroy tissues to stop bleeding and promote healing. Cauterization has been largely replaced by electrocoagulation, which is the use of a high-frequency electric current to seal blood vessels by heat and thus stop bleeding.

  11. Surgical management of metastatic long bone fractures: principles and techniques.

    PubMed

    Scolaro, John Alan; Lackman, Richard D

    2014-02-01

    Management of metastatic long bone fractures requires identification of the lesion and the use of sound fracture fixation principles to relieve pain and restore function. The treating surgeon must understand the principles of pathologic fracture fixation before initiating treatment. Because these fractures occur in the context of a progressive systemic disease, management typically involves a multidisciplinary approach. When considering surgical stabilization of these fractures, the abnormal (or absent) healing environment associated with diseased bone and the overall condition of the patient must be taken into account. The goal of surgery is to obtain a rigid mechanical construct, which allows for early mobility and weight bearing. This can be achieved using internal fixation with polymethyl methacrylate cement or segmental resection and joint reconstruction. Prosthetic joint arthroplasty is a more reliable means of fracture management when insufficient bone is present for fixation. Prophylactic stabilization of impending pathologic fractures can reduce the morbidity associated with metastatic lesions.

  12. Surgical time for graft preparation using different suture techniques

    PubMed Central

    Camarda, Lawrence; Giambartino, Sebastian; Lauria, Michele; Saporito, Michele; Triolo, Vito; D’Arienzo, Michele

    2016-01-01

    Summary Background The purpose of the present study was to compare the operative time for graft preparation using different techniques for graft suturing. Material and methods Flexor profundus tendons were harvested from fresh pig hind-leg trotters. Three different suture techniques were investigated: the Krackow stitch (K), the Whipstitch (W), and the Modified Finger-Trap suture (MFT). Tendons were sutured starting at 10 mm from the distal free end of the tendon. The suture configurations of the Krackow stitch and Whipstitch were completed with five suture throws. According to the MFT technique, the suture was wrapped five times around the tendon over a distance of 30 mm. The time required to perform a complete suture on each tendon was measured. Five independent examiners of different levels of training measured the time required for graft preparation during 3 separate occasions to determine intraobserver repeatability and interobserver reproducibility. Results The mean time required for graft preparation following the Krackow technique was 69.1 seconds ± 18.3 SD (range 31.8–120). The Whipstitch technique took an average of 59.9 seconds ± 21.2 SD (range 27–93). The MFT suture required a mean of 29.3 seconds ± 11.4 SD for completing the suture (range 21.6–33). In all examiners the time required to complete the MFT suture was significantly less than the other suture techniques (p < 0.05). Intraobserver intraclass correlation coefficients for each examiner ranged from 0.72 to 0.83. Conclusion Low graft preparation time is required to complete a MFT suture in a porcine tendon model. Further, time required for graft preparation using the MFT was shorter than other suturing techniques such as the Krackow and Whipstitch techniques. Clinical relevance The MFT suture could be used for graft set-up with the main advantage of reducing the time required in comparison with other suture techniques. PMID:27900298

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

    PubMed Central

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

    2016-01-01

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

  14. 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

  15. 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.

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

    PubMed

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

    2010-09-01

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

  17. Simulation for optimal design of hand-held surgical robots.

    PubMed

    Zahraee, Ali Hassan; Szewczyk, Jerome; Morel, Guillaume

    2009-01-01

    Hand-held surgical robots are manipulators with dexterous effectors to be used by surgeons in minimally invasive surgery and especially in laparoscopy. Mechanical manipulators for laparoscopy have appeared on the markets in recent years with various interfaces and dexterities. 2 examples are RealHand and Laparo-Angle. The question of which interface and control mode is the best has not been answered yet. Also, the effector kinematics has not been studied much. We have made a simulator to study the robot's interface, control mode and kinematics to design a hand-held surgical robot for laparoscopic surgery. We asked test subjects to use the simulator and try to make sutures in a virtual environment. Users opinion is that a joystick as interface is easier to use, compared to a jointed interface translating hand's orientation to that of the effector. It appears that a 6 DOF effector coupled to the shaft is necessary and dexterous enough to make sutures in different angles.

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

    PubMed

    Konda, Vani Ja; Dalal, Kunal

    2011-01-01

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

  19. Frenectomy: a review with the reports of surgical techniques.

    PubMed

    Devishree; Gujjari, Sheela Kumar; Shubhashini, P V

    2012-11-01

    The frenum is a mucous membrane fold that attaches the lip and the cheek to the alveolar mucosa, the gingiva, and the underlying periosteum. The frena may jeopardize the gingival health when they are attached too closely to the gingival margin, either due to an interference in the plaque control or due to a muscle pull. In addition to this, the maxillary frenum may present aesthetic problems or compromise the orthodontic result in the midline diastema cases, thus causing a recurrence after the treatment. The management of such an aberrant frenum is accomplished by performing a frenectomy.The present article is a compilation of a brief overview about the frenum, with a focus on the indications, contraindications, advantages and the disadvantages of various frenectomy techniques, like Miller's technique, V-Y plasty, Z-plasty and frenectomy by using electrocautery. A series of clinical cases of frenectomy which were approached by various techniques have also been reported.

  20. Frenectomy: A Review with the Reports of Surgical Techniques

    PubMed Central

    Devishree; Gujjari, Sheela Kumar; Shubhashini, P.V.

    2012-01-01

    The frenum is a mucous membrane fold that attaches the lip and the cheek to the alveolar mucosa, the gingiva, and the underlying periosteum. The frena may jeopardize the gingival health when they are attached too closely to the gingival margin, either due to an interference in the plaque control or due to a muscle pull. In addition to this, the maxillary frenum may present aesthetic problems or compromise the orthodontic result in the midline diastema cases, thus causing a recurrence after the treatment. The management of such an aberrant frenum is accomplished by performing a frenectomy. The present article is a compilation of a brief overview about the frenum, with a focus on the indications, contraindications, advantages and the disadvantages of various frenectomy techniques, like Miller's technique, V-Y plasty, Z-plasty and frenectomy by using electrocautery. A series of clinical cases of frenectomy which were approached by various techniques have also been reported. PMID:23285469

  1. Using biomechanics to improve the surgical technique for internal fixation of intracapsular femoral neck fractures.

    PubMed

    Wu, Chi-Chuan

    2010-01-01

    Despite advances in science and technology, the success rate for the treatment of displaced intracapsular femoral neck fractures in high-energy injuries remains disappointing. The blood supply system in the femoral head of humans does not favor recovery from these fractures. Once these fractures occur, osteonecrosis and nonunion rates may be as high as 30%, even if the newest technique is used. There are some surgical techniques used to supplement internal fixation to reestablish the blood supply in the femoral head, but none have been evidently successful. After analysis of related studies, the author concludes that immediate surgical treatment using improved techniques incorporating the principles of biomechanics can improve the success rate of treatment of these fractures. Using these principles, the fracture site can achieve sufficient stability. Consequently, the blood supply in the femoral head and neck can be reestablished earlier and loss of reduction of fragments during treatment can be minimized. Thus, the chance of full recovery from these complicated fractures can be maximized. In this study, the biomechanical characteristics of these fractures and the principles associated with the surgical techniques used for treating them are reviewed and clarified. Finally, a surgical technique which is ideal from the author's viewpoint is presented. The author believes that the recommended surgical technique may become the best method for treating these complicated fractures.

  2. 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

  3. 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.

  4. Novel surgical techniques, regenerative medicine, tissue engineering and innovative immunosuppression in kidney transplantation

    PubMed Central

    Nowacki, Maciej; Nazarewski, Łukasz; Tyloch, Dominik; Pokrywczyńska, Marta; Pietkun, Katarzyna; Jundziłł, Arkadiusz; Tyloch, Janusz; Habib, Samy L.; Drewa, Tomasz

    2016-01-01

    On the 60th anniversary of the first successfully performed renal transplantation, we summarize the historical, current and potential future status of kidney transplantation. We discuss three different aspects with a potential significant influence on kidney transplantation progress: the development of surgical techniques, the influence of regenerative medicine and tissue engineering, and changes in immunosuppression. We evaluate the standard open surgical procedures with modern techniques and compare them to less invasive videoscopic as well as robotic techniques. The role of tissue engineering and regenerative medicine as a potential method for future kidney regeneration or replacement and the interesting search for novel solutions in the field of immunosuppression will be discussed. After 60 years since the first successfully performed kidney transplantation, we can conclude that the greatest achievements are associated with the development of surgical techniques and with planned systemic immunosuppression. PMID:27695507

  5. Liver transplantation surgical techniques for extensive retroperitoneal tumor with major blood vessel involvement: a case report.

    PubMed

    Miura, K; Sato, Y; Kokai, H; Hara, Y; Kobayashi, T; Oya, H; Yamamoto, S; Hatakeyama, K

    2012-03-01

    A case of a 71-year-old man with a huge retroperitoneal tumor situated behind the liver, which strongly compressed the liver inferior vena cava (IVC), and gastrointestinal tract is described. With the techniques of whole liver extraction and autologous orthotopic liver transplantation, we successfully removed the tumor. We have the surgical techniques, essential elements, and indications for this procedure.

  6. Surgical management of Gorlin syndrome: a 4-decade experience using local excision technique.

    PubMed

    Griner, Devan; Sutphin, Daniel; Sargent, Larry A

    2015-04-01

    Basal cell nevus syndrome (aka Gorlin syndrome, Gorlin-Goltz syndrome, nevoid basal cell carcinoma syndrome, and fifth phacomatosis) is a rare but well-described autosomal dominant condition with variable penetrance. We present a female patient who has been successfully treated using local surgical excision and diligent skin surveillance for more than 4 decades, demonstrating that simple local incision is an efficacious and reasonable surgical alternative that may circumvent the specialization and expense of Mohs technique.

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

    PubMed Central

    Gonzalez, Tyler; Chien, Bonnie; Ghorbanhoseini, Mohammad; Kwon, John Y.

    2017-01-01

    Wound complications following ankle fracture surgery are a major concern. Through the use of minimally invasive surgical techniques some of these complications can be mitigated. Recent investigations have reported on percutaneous fixation of distal fibula fractures demonstrating similar radiographic and functional outcomes to traditional open approaches. The purpose of this manuscript is to describe in detail the minimally invasive surgical approach for distal fibula fractures. PMID:28271086

  8. [Orthotopic liver transplant in rats. Surgical technique, complications and treatment].

    PubMed

    Lausada, Natalia R; Gondolesi, G E; Ortiz, E; Dreizzen, E; Raimondi, J C

    2002-01-01

    The orthotopic rat liver transplant model is a widely used technique in transplantation research. It has many advantages over other animal transplant models because of its availability and low cost. However, it must be emphasized that success with the rat model requires thorough training. The aim of this paper is to describe the microsurgical technique involved in 60 rat liver transplants and to discuss the complications and their treatments. Forty-nine liver transplants were performed at the Experimental Laboratory of the University Hospital, Ontario, Canada (ELUH) and 11 were performed at the Laboratorio de Trasplante de Organos de la Facultad de Ciencias Médicas de La Plata, Buenos Aires. Argentina (LTO). Among the transplants performed at the ELUH, the observed complications were haemorrhage (n = 4), pneumothorax (n = 1), anastomotic failure (n = 15), bile leak (n = 3), and bile duct necrosis (n = 9). The remaining 17 rats at the ELUH were healthy at day 7 after surgery. Animal survival immediately postop, at 24 hours postop and at 7 days postop was achieved with the 9th, 20th and 21st transplants respectively. At the LTO, 3 rats died as a result of anaesthetic complications. Seven-day animal survival was achieved with the 11th transplant. We beleive that the description of the orthotopic rat liver transplantation technique, as well as the discussion regarding complications and their management, can be useful for researchers interested in performing liver transplantation in rats.

  9. Surgical techniques for cochlear implantation in the very young child.

    PubMed

    Parisier, S C; Chute, P M; Popp, A L; Hanson, M B

    1997-09-01

    Early cochlear implantation to treat prelingually deafened children has been shown to improve speech perception and overall performance. The current age limit for implantation is 24 months in accordance with US Food and Drug Administration guidelines, but it is believed that earlier implantation is possible and may result in better performance. Implantation in children younger than 36 months, however, is complicated by the altered anatomy of the temporal bone in this young age group. We have developed specific modifications in the cochlear implantation technique for this young age group. This technique was used in implantation for 17 children younger than 36 months. The ages ranged from 16 to 36 months and averaged 30 months. All patients except one had complete electrode insertion without complication. The technique of cochlear implantation must be modified not only for differences in anatomy in these young children but also for the expected continued growth of the temporal bone and related structures. Cochlear implantation can be safely performed on children as young as 16 months.

  10. 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.

  11. Influence of surgical technique, implant shape and diameter on the primary stability in cancellous bone.

    PubMed

    Bilhan, H; Geckili, O; Mumcu, E; Bozdag, E; Sünbüloğlu, E; Kutay, O

    2010-12-01

    Achievement of primary stability during surgical placement of dental implants is one of the most important factors for successful osseointegration depending on various anatomical, surgical and implant-related factors. Resonance frequency analysis (RFA) has been shown as a non-invasive and objective technique for measuring the stability of implants. The aim of this study was to evaluate the effect of some surgical and implant-related factors in enhancing primary stability and to estimate a correlation between RFA and insertion torque (IT) in proximal regions of cow ribs representing cancellous bone. Fifteen implant beds were prepared in the most proximal region of six fresh cow ribs. Ninety implants with three different shapes and two different diameters were placed with two different surgical techniques, and the primary stability was compared using RFA and IT. Significantly higher RFA and IT values were achieved when under-dimensioned drilling was used as the surgical method (P<0·01); significantly higher IT values were obtained with the use of wider implants (P<0·01) and partially conical Astra Tech implants showed the highest IT values (P<0·01). When all the implants were considered, significant correlations between the IT and RFA values were noted (%40·6, P<0·05). Partially conical implants with a wide diameter to be placed with the modified surgical technique proposed appear to be useful in enhancing the primary stability in cancellous bone.

  12. Surgical technique for lung retransplantation in the mouse

    PubMed Central

    Li, Wenjun; Goldstein, Daniel R.; Bribriesco, Alejandro C.; Nava, Ruben G.; Spahn, Jessica H.; Wang, Xingan; Gelman, Andrew E.; Krupnick, Alexander S.

    2013-01-01

    Microsurgical cuff techniques for orthotopic vascularized murine lung transplantation have allowed for the design of studies that examine mechanisms contributing to the high failure rate of pulmonary grafts. Here, we provide a detailed technical description of orthotopic lung retransplantation in mice, which we have thus far performed in 144 animals. The total time of the retransplantation procedure is approximately 55 minutes, 20 minutes for donor harvest and 35 minutes for the implantation, with a success rate exceeding 95%. The mouse lung retransplantation model represents a novel and powerful tool to examine how cells that reside in or infiltrate pulmonary grafts shape immune responses. PMID:23825768

  13. 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

  14. 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.

  15. [Optimal indication for surgical ventricular restoration for dilated cardiomyopathy].

    PubMed

    Wakasa, Satoru; Shingu, Yasushige; Kubota, Suguru; Minamida, Taro; Iijima, Makoto; Naito, Yuji; Ooka, Tomonori; Tachibana, Tsuyoshi; Matsui, Yoshiro

    2013-01-01

    In this study, we assessed mid-term results of surgical ventricular restoration (SVR) for dilated cardiomyopathy. The study subjects were 107 patients who underwent SVR for both ischemic (ischemic cardiomyopathy:ICM, n=57) and non-ischemic (dilated cardiomyopathy:DCM, n=50) dilated cardiomyopathy. In 49(86%)patients ICM was associated with New York heart Association(NYHA) class III or more. Preoperative left ventricular ejection fraction (LVEF) and left ventricular end-diastolic dimension(LVDd)were 22±6% and 67±9 mm, respectively. Hospital mortality was 14% and 5-year mortality was 40%. In contrast, 46( 92%) of the DCM patients presented with NYHA class III or more. Preoperative LVEF and LVDd were 20±6% and 74±9 mm, respectively. Hospital mortality was 28% and 5-year mortality was 63%. For NYHA class III or less, however, 5-year mortality rates were 23% and 39% in those with ICM and DCM, respectively. For those with NYHA functional class III or less, SVR was associated with a satisfactory survival rate and is recommended. For those with severe heart failure, however, ventricular assist devices or heart transplantation may have to be indicated.

  16. Evaluation of the effect of pulmonary hydatid cyst location on the surgical technique approaches

    PubMed Central

    Sadrizadeh, Ali; Haghi, Seyed Ziaollah; Masuom, Seyed Hossein Fattahi; Bagheri, Reza; Dalouee, Marziyeh Nouri

    2014-01-01

    Purpose: A hydatid cyst is the most common lung parasitic disease and is endemic in Iran. A hydatid cyst is more common in the right lung and lower lobes. Objective: The aim of this study was to assess surgical treatment of pulmonary hydatid cysts and whether the location of cyst affects surgical technique approaches. Materials and Methods: This study was performed on 87 patients with a pulmonary hydatid cyst who were referred to Qaem Hospital from 2010 to 2012. Selection of surgical technique was according to size, location, and the number of cysts. Patients were divided into two groups: (1) surgery with preserving lung parenchyma and (2) lobectomy. Afterward, the relationship between the location of cyst and surgical technique approaches was evaluated. Data was analyzed by Chi-square and Fisher exact tests. Results: In this study, no significant relation was found between the size (P = 0.682) and number (P = 0.344) of cysts and lobectomy necessity. But, there was a significant relation between the occurrence of cyst in middle lobe and lobectomy necessity (P = 0.016). Conclusions: According to the results, type of surgical technique does not depend on the size and number of cysts, but it may be related to the location of the cyst and the ratio of lung destruction. PMID:25378844

  17. Robotic assisted adrenalectomy: Surgical techniques, feasibility, indications, oncological outcome and safety.

    PubMed

    Yiannakopoulou, Eugenia

    2016-04-01

    Nowadays robotic assisted adrenalectomy has become an alternative to conventional laparoscopic adrenalectomy. However, evidence on the possible advantages and drawbacks of robotic assisted adrenalectomy remains still limited. This manuscript aimed to review evidence on robotic assisted adrenalectomy in terms of surgical technique, feasibility, indications, oncological outcome and safety. Existing evidence, although limited, suggests that robotic assisted adrenalectomy is feasible and safe. However, the number of patients submitted to robotic assisted adrenalectomy is limited with the majority of them being operated for benign disease. There are only a few case reports of robotic assisted adrenalectomy performed for adrenocortical carcinoma, oncocytoma or metastasis. Partial adrenalectomy seems to be a promising application of robotic assisted adrenalectomy especially for the treatment of hereditary pheocromocytomas. Robotic assisted adrenalectomy overcoming the technical limitations of laparoscopic surgery could possibly elicit a mild surgical response instead of the well described surgical response. Surgical response affects surgical morbidity and mortality as well as oncological outcome of malignant disease. If this hypothesis is proved correct, robotic assisted adrenalectomy could be possibly indicated in the treatment of disease. In conclusion, robotic assisted adrenalectomy is feasible and safe. Further research is needed on the oncological outcome of this minimally invasive technique as well as on its effect on surgical stress response.

  18. 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.

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

    PubMed Central

    Wang, Chenglong; Gui, Lai

    2015-01-01

    Summary: 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

  20. A surgical technique to protect the macular hole in indocyanine green-assisted vitrectomy.

    PubMed

    Saito, Masaaki; Iida, Tomohiro

    2006-01-01

    To prevent indocyanine green (ICG) toxicity during macular hole repair, a surgical technique was designed in which the hole is protected by a viscoelastic material before injecting ICG to stain the internal limiting membrane. The area covered by the viscoelastic material was not stained by ICG. The internal limiting membrane was peeled without difficulty by taking advantage of the ICG stain outlining it. After surgery, all holes closed and the postoperative outcomes were favorable. Only a small amount of residual ICG remained in the macular area. This surgical technique does not interfere with internal limiting membrane peeling and reduces the residual ICG postoperatively.

  1. Nasal packing and transseptal suturing techniques: surgical and anaesthetic perspectives.

    PubMed

    Günaydın, Rıza Önder; Aygenc, Erdinc; Karakullukcu, Selma; Fidan, Fatih; Celikkanat, Serdar

    2011-08-01

    The objective of this study is to compare the nasal packing and the transseptal suturing techniques regarding the extubation difficulty evaluation scores, follow-up times in post-anaesthesia care unit (PACU), pain scores, and postoperative complications. Two hundred patients who underwent septoplasty from January 2009 to October 2009 were randomly assigned either to have nasal packs (n: 100) or transeptal sutures (n: 100). In the transseptal suture group, extubation was easier and PACU follow-up times were shorter, when compared to the nasal packing group (p < 0.001). Patients with nasal packing had significantly higher pain scores (p < 0.001). Minor bleeding was significantly higher in the transseptal group with seven cases, compared to the nasal packing group without any bleeding cases (p = 0.014). There were two patients who had postoperative major bleeding, and two patients who had septal hematoma in the transseptal suture group. One patient with nasal packing had postoperative infection. Septal perforation was not seen in any of the cases. While patients in both groups experienced postoperative crusting, patients in the transseptal suture group also complained about foreign body sensation. Extubation was more comfortable; post-anaesthesia monitorization duration was shorter, and postoperative pain was less, but minor bleeding was seen more with transseptal sutures. There was no significant difference in terms of major bleeding, hematoma, infection or perforation. Foreign body sensation was the main cause of postoperative discomfort in the transseptal suture group. Transseptal suturing might be a significantly comfortable, cost-effective and reliable alternative to nasal packing.

  2. 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.

  3. Parma tracheostomy technique: a hybrid approach to tracheostomy between classical surgical and percutaneous tracheostomies

    PubMed Central

    Benassi, Filippo; Manca, Tullio; Ramelli, Andrea; Vezzani, Antonella; Nicolini, Francesco; Romano, Giorgio; Ricci, Matteo; Carino, Davide; Di Chicco, Maria Vincenza; Gherli, Tiziano

    2016-01-01

    Background The aim of our study is to compare the classical surgical tracheostomy (TT) technique with a modified surgical technique designed and created by the cardiothoracic surgery staff of our department to reduce surgical trauma and postoperative complications. This modified technique combines features of percutaneous TT and surgical TT avoiding the use of specialized tools, which are required in percutaneous TT. Methods From October 2008 to March 2014 we performed 67 tracheostomies using this New Modified Surgical Technique (NMST) and 56 TT with the Classical Surgical Technique (CST). We collected data about the early clinical complications, deaths TT-related, deaths due to other complications and the presence of late TT’s complications were performed by a telephone follow-up. SPSS software (IMB version 21) was used for the statistical analysis. Categorical data were treated with chi-square test and continuous data were treated with t-test for independent samples. Results NMST group had a significant lower number of early complications (P=0.005) compared to CST group (5 vs. 15). In-hospital mortality was significantly higher in CST group (18 deaths vs. 4 in NMST group, P=0.001) but we registered only one case of TT-related mortality in CST group (P=0.280). We did not note other differences between the two groups regarding short or mid-long term complications. Conclusions In our experience the NMST demonstrated to be easily safe and reproducible with an amount of early, mid- and long-term complications similar to the CST; furthermore the aesthetic results of the procedure appear similar to those of percutaneous TT. PMID:28149558

  4. Distraction osteogenesis: a new surgical technique for use with the multiplanar mandibular distractor.

    PubMed

    Gateño, J; Teichgraeber, J F; Aguilar, E

    2000-03-01

    If distraction osteogenesis is to reach its full potential and achieve the level of accuracy that is possible with orthognathic surgery, its outcomes need to be as predictable. To this end, the authors developed a planning process for distraction osteogenesis similar to that used in orthognathic surgery. However, the success of the planning process depends on the authors' ability to execute the plan at the time of surgery. As a result, the authors needed to develop a surgical technique that would enable them to precisely install the distractor as indicated in the presurgical plan. The surgical technique presented in this article was developed for this purpose. The authors used this technique in seven patients (four boys and three girls; age range, 4 to 10 years). Four patients presented with unilateral deformities, and three patients presented with bilateral deformities. The follow-up period in this group of patients ranged from 12 to 33 months. The purpose of the technique is to replicate the position of the distractor on the mandible as determined by the presurgical plan. To this purpose, a custom drill guide and a surgical template have been developed. Both of these are used following the principles of triangulation to establish the pin position and orientation of the distractor. In the authors' hands, the use of this surgical technique has resulted in outcomes close to those predicted by the planning process.

  5. Individualized optimal surgical extent of the lateral neck in papillary thyroid cancer with lateral cervical metastasis.

    PubMed

    Park, Jae-Yong; Koo, Bon Seok

    2014-06-01

    Despite an excellent prognosis, cervical lymph node (LN) metastases are common in patients with papillary thyroid cancer (PTC). The presence of metastasis is associated with an increased risk of locoregional recurrence, which significantly impairs quality of life and may decrease survival. Therefore, it has been an important determinant of the extent of lateral LN dissection in the initial treatment of PTC patients with lateral cervical metastasis. However, the optimal extent of therapeutic lateral neck dissection (ND) remains controversial. Optimizing the surgical extent of LN dissection is fundamental for balancing the surgical morbidity and oncological benefits of ND in PTC patients with lateral neck metastasis. We reviewed the currently available literature regarding the optimal extent of lateral LN dissection in PTC patients with lateral neck metastasis. Even in cases with suspicion of metastatic LN at the single lateral level or isolated metastatic lateral LN, the application of ND including all sublevels from IIa and IIb to Va and Vb may be overtreatment, due to the surgical morbidity. When there is no suspicion of LN metastasis at levels II and V, or when multilevel aggressive neck metastasis is not found, sublevel IIb and Va dissection may not be necessary in PTC patients with lateral neck metastasis. Thus consideration of the individualized optimal surgical extent of lateral ND is important when treating PTC patients with lateral cervical metastasis.

  6. 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.

  7. The core of a competent surgeon: a working knowledge of surgical anatomy and safe dissection techniques.

    PubMed

    Rogers, Robert M; Taylor, Richard H

    2011-12-01

    The competent gynecologic surgeon has a sure, working knowledge of the anatomy in the field of pelvic dissection and is expert in the techniques and in the millimeter by millimeter progression of surgical dissections. When operating in the pelvis, the surgeon always asks several questions. The first is, “In what anatomic area am I dissecting?” This question defines the anatomy to be dissected out. The second is,“What dissection techniques will I use here?” The measured steps of surgical dissection give the surgeon the confidence to proceed with the operation, while safeguarding the integrity of the surrounding anatomic structures. With less blood loss and less trauma to the tissues and anatomic structures, the surgeon may expect a better surgical outcome for the patient.

  8. [Forum on tissue expansion. Expansion of the scalp. Surgical techniques and clinical applications].

    PubMed

    Foyatier, J L; Delay, E; Comparin, J P; Latarjet, J; Masson, C L

    1993-02-01

    Repair of all forms of alopecia is one of the principal applications of scalp expansion. The authors have inserted 400 expansion prostheses, including 20 in the scalp. The surgical technique, choice of material and various types of flaps are described and illustrated by clinical cases of extensive alopecia.

  9. 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

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

    PubMed Central

    Guevara-Villarreal, Dante A.

    2016-01-01

    Ocular penetrating injury with Intraocular Foreign Body (IOFB) is a common form of ocular injury. Several techniques to remove IOFB have been reported by different authors. The aim of this publication is to review different timing and surgical techniques related to the extraction of IOFB. Material and Methods. A PubMed search on “Extraction of Intraocular Foreign Body,” “Timing for Surgery Intraocular Foreign Body,” and “Surgical Technique Intraocular Foreign Body” was made. Results. Potential advantages of immediate and delayed IOFB removal have been reported with different results. Several techniques to remove IOFB have been reported by different authors with good results. Conclusion. The most important factor at the time to perform IOFB extraction is the experience of the surgeon. PMID:28025619

  11. Surgically facilitated orthodontic therapy: a new tool for optimal interdisciplinary results.

    PubMed

    Roblee, Richard D; Bolding, Scotty L; Landers, Jason M

    2009-06-01

    Restorative-driven interdisciplinary therapy frequently requires orthodontic therapy to optimally address the underlying dentofacial problems. Limitations in traditional orthodontic techniques and the length of requisite treatment times often create barriers to providers and patients' willingness to accept orthodontics as part of the overall treatment plan. Two main types of surgically facilitated orthodontic therapy (SFOT), each with its own indications and protocols, are becoming popular. They can expand significantly the limitations of orthodontics and greatly shorten treatment times. The first uses corticotomies to cause bone demineralization through a regional acceleratory phenomenon (RAP) that "supercharges" dentoalveolar tooth movement. The second type of SFOT involves single- or multiple-tooth osteotomies combined with the principles of distraction osteogenesis to rapidly grow hard and soft tissues, thereby enabling changes in alveoloskeletal relationships. With these SFOT procedures, an interdisciplinary team can modify predictably the dentoalveolar complex so the teeth, alveolar bone, and skeletal components are addressed properly to maximize ideal functional and esthetic relationships, while greatly reducing treatment time and increasing stability of the result.

  12. 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

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

    PubMed Central

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

    2010-01-01

    Aims We report the case of a myopic patient who, after intraocular lens transplant in the posterior chamber, suffered elevated intraocular pressure due to pigment dispersion, with recurrent episodes of blurred vision. The patient was treated with a new surgical technique that can avoid potential iridolenticular contact. Methods Complete ophthalmologic examination and optical coherence tomography (OCT) of the anterior segment were performed. Results Contact between the pigmentary epithelium and the iris with an intraocular lens was revealed by utrasound biomicroscopy and OCT. In this case, Nd:YAG laser iridotomy and laser iridoplasty were not effective for iridolenticular separation and control of the pigment dispersion. We propose a new technique: stitches on the surface of the iris to obtain good iridolenticular separation and good intraocular pressure control. Conclusion Stitches on the iris surface should be considered as optional therapy in pigmentary glaucoma secondary to intraocular lens implantation. This surgical technique can avoid potential iridolenticular contacts more definitively. PMID:21151331

  14. Complications, Not Minimally Invasive Surgical Technique, Are Associated with Increased Cost after Esophagectomy

    PubMed Central

    Fu, Sue J.; Ho, Vanessa P.; Ginsberg, Jennifer; Perry, Yaron; Delaney, Conor P.; Linden, Philip A.

    2016-01-01

    Background. Minimally invasive esophagectomy (MIE) techniques offer similar oncological and surgical outcomes to open methods. The effects of MIE on hospital costs are not well documented. Methods. We reviewed the electronic records of patients who underwent esophagectomy at a single academic institution between January 2012 and December 2014. Esophagectomy techniques were grouped into open, hybrid, MIE, and transhiatal (THE) esophagectomy. Univariate and multivariate analyses were performed to assess the impact of surgery on total hospital cost after esophagectomy. Results. 80 patients were identified: 11 THE, 11 open, 41 hybrid, and 17 MIE. Median total cost of the hospitalization was $31,375 and was similar between surgical technique groups. MIE was associated with higher intraoperative costs, but not total hospital cost. Multivariable analysis revealed that the presence of a complication, increased age, American Society of Anesthesiologists class IV (ASA4), and preoperative coronary artery disease (CAD) were associated with significantly increased cost. Conclusions. Despite the association of MIE with higher operation costs, the total hospital cost was not different between surgical technique groups. Postoperative complications and severe preoperative comorbidities are significant drivers of hospital cost associated with esophagectomy. Surgeons should choose technique based on clinical factors, rather than cost implications. PMID:28053785

  15. Winglet design using multidisciplinary design optimization techniques

    NASA Astrophysics Data System (ADS)

    Elham, Ali; van Tooren, Michel J. L.

    2014-10-01

    A quasi-three-dimensional aerodynamic solver is integrated with a semi-analytical structural weight estimation method inside a multidisciplinary design optimization framework to design and optimize a winglet for a passenger aircraft. The winglet is optimized for minimum drag and minimum structural weight. The Pareto front between those two objective functions is found applying a genetic algorithm. The aircraft minimum take-off weight and the aircraft minimum direct operating cost are used to select the best winglets among those on the Pareto front.

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

    PubMed

    Tibbs, Sheila Marie; Moss, Jacqueline

    2014-11-01

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

  17. Optimized feline vitrectomy technique for therapeutic stem cell delivery to the inner retina

    PubMed Central

    Jayaram, Hari; Becker, Silke; Eastlake, Karen; Jones, Megan F; Charteris, David G; Limb, G Astrid

    2014-01-01

    Objective To describe an optimized surgical technique for feline vitrectomy which reduces bleeding and aids posterior gel clearance in order to facilitate stem cell delivery to the inner retina using cellular scaffolds. Procedures Three-port pars plana vitrectomies were performed in six-specific pathogen-free domestic cats using an optimized surgical technique to improve access and minimize severe intraoperative bleeding. Results The surgical procedure was successfully completed in all six animals. Lens sparing vitrectomy resulted in peripheral lens touch in one of three animals but without cataract formation. Transient bleeding from sclerotomies, which was readily controlled, was seen in two of the six animals. No cases of vitreous hemorrhage, severe postoperative inflammation, retinal detachment, or endophthalmitis were observed during postoperative follow-up. Conclusions Three-port pars plana vitrectomy can be performed successfully in the cat in a safe and controlled manner when the appropriate precautions are taken to minimize the risk of developing intraoperative hemorrhage. This technique may facilitate the use of feline models of inner retinal degeneration for the development of stem cell transplantation techniques using cellular scaffolds. PMID:24661435

  18. Sutureless surgical techniques for arch aneurysm repair in a patient with Behçet's disease.

    PubMed

    Uchida, Naomichi; Takasaki, Taiichi; Takahashi, Shinya; Sueda, Taijiro

    2014-01-01

    In patients with vasculo-Behçet's disease, endovascular stent graft is a reasonable treatment from the viewpoint of prevention of an anastomotic pseudo-aneurysm. We report a case of total arch replacement combined with open stent grafting technique to the downstream aorta and graft inclusion into sino-tubular junction as sutureless surgical techniques for an arch aneurysm in a 42-year-old woman with Behçet's disease. Postoperative computed tomography (CT) showed that the aortic aneurysm had completely disappeared in 11 months after the operation. Open stent grafting technique was effective to prevent anastomotic pseudo-aneurysm formation.

  19. Preservation of the Pulmonary Valve During Early Repair of Tetralogy of Fallot: Surgical Techniques.

    PubMed

    Vida, Vladimiro L; Guariento, Alvise; Zucchetta, Fabio; Padalino, Massimo; Castaldi, Biagio; Milanesi, Ornella; Stellin, Giovanni

    2016-01-01

    During the last decade interest in preserving pulmonary valve (PV) function has stimulated a few surgeons to apply valve-sparing techniques in repairing tetralogy of Fallot (TOF), with the aim of preserving long-term right ventricular function. Since June 2007, we embarked upon a program for preserving PV function in selected patients during TOF repair. More recently, the introduction of more complex PV plasty techniques allowed us to further extend the applicability of PV preservation techniques. We believe that preservation of PV function during early repair of TOF, by combining different intraoperative surgical maneuvers, can be extended to almost all patients with classic TOF.

  20. Assembly, checkout, and operation optimization analysis technique for complex systems

    NASA Technical Reports Server (NTRS)

    1968-01-01

    Computerized simulation model of a launch vehicle/ground support equipment system optimizes assembly, checkout, and operation of the system. The model is used to determine performance parameters in three phases or modes - /1/ systems optimization techniques, /2/ operation analysis methodology, and /3/ systems effectiveness analysis technique.

  1. Extended endoscopic endonasal transsphenoidal approach for retrochiasmatic craniopharyngioma: Surgical technique and results

    PubMed Central

    Sankhla, Suresh K.; Jayashankar, Narayan; Khan, Ghulam M.

    2015-01-01

    Objective: Surgical treatment of retrochiasmatic craniopharyngioma still remains a challenge. While complete removal of the tumor with preservation of the vital neurovascular structures is often the goal of the treatment, there is no optimal surgical approach available to achieve this goal. Transcranial and transsphenoidal microsurgical approaches, commonly used in the past, have considerable technical limitations. The extended endonasal endoscopic surgical route, obtained by removal of tuberculum sellae and planum sphenoidale, offers direct midline access to the retrochiasmatic space and provides excellent visualization of the undersurface of the optic chiasm. In this report, we describe the technical details of the extended endoscopic approach, and review our results using this approach in the surgical management of retrochiasmatic craniopharyngiomas. Methods: Fifteen children, including 9 girls and 6 boys, aged 8 to 15 years underwent surgery using extended endoscopic transsphenoidal approach between 2008 and 2014. Nine patients had a surgical procedure done previously and presented with recurrence of symptoms and regrowth of their residual tumors. Results: A gross total or near total excision was achieved in 10 (66.7%) patients, subtotal resection in 4 (26.7%), and partial removal in 1 (6.7%) patient. Postoperatively, headache improved in 93.3%, vision recovered in 77.3%, and the hormonal levels stabilised in 66.6%. Three patients (20%) developed postoperative CSF leaks which were managed conservatively. Three (20%) patients with diabetes insipidus and 2 (13.3%) with panhypopituitarism required long-term hormonal replacement therapy. Conclusions: Our early experience suggests that the extended endonasal endoscopic approach is a reasonable option for removal of the retrochiasmal craniopharyngiomas. Compared to other surgical approaches, it provides better opportunities for greater tumor removal and visual improvement without any increase in risks. PMID:26962333

  2. [Surgical techniques in mitral valve diseases. Reconstruction and/or replacement].

    PubMed

    Noack, T; Mohr, F-W

    2016-02-01

    Mitral valve (MV) disease is one of the most common heart valve diseases. The surgical and interventional treatment for MV disease requires a multidisciplinary approach. For primary mitral valve regurgitation (MVR) surgical MV repair is the treatment of choice, which can be performed with an excellent outcome and long-term survival in reference centers. The surgical technique used for MV repair depends on the pathological mechanism, the morphological dimensions of the MV, the operative risk and the expertise of the cardiac surgeon. The surgical and interventional treatment of secondary MVVR is the subject of on-going discussions. In patients with moderate secondary MVR undergoing coronary artery bypass grafting, concomitant MV repair should be performed. In the presence of severe secondary MR with risk factors for failure of MV repair, patients should consider having MV replacement. In the rare cases of patients presenting with mitral valve stenosis (MVS) MV repair can be considered in young patients and who are most often treated with MV replacement. The choice between biological or mechanical MV replacement depends on the pathophysiology, the comorbidities, the amount of anticoagulation necessary and the age of the patient. New percutaneous techniques for MV replacement offer new treatment options for reoperation in high-risk patients.

  3. 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.

  4. An optimal GPS data processing technique

    NASA Technical Reports Server (NTRS)

    Wu, S. C.; Melbourne, W. G.

    1992-01-01

    A formula is derived to optimally combine dual-frequency GPS (Global Positioning System) pseudorange and carrier phase data streams into a single equivalent data stream, reducing the data volume and computing time in the filtering process for parameter estimation by a factor of four. The resulting single data stream is that of carrier phase measurements with both data noise and bias uncertainty strictly defined. With this analytical formula the single stream of equivalent GPS measurements can be efficiently formed by simple numerical calculations without any degradation in data strength. The formulation for the optimally combined GPS data and their covariances are given in closed form. Carrier phase ambiguity resolution, when feasible, is improved due to the preservation of the full data strength with the optimal data combining process.

  5. Variable Expansion Techniques for Decomposable Optimization Problems

    DTIC Science & Technology

    2011-03-05

    meration or dynamic programming. Recall the edge partition problem studied by Taskin et al. above in reference 7. (Z. Caner Taskin was supported by the...Stochastic Integer Program- ming, August 2009 August 2009. 12 2. Z. Caner Taskin, Algorithms for Solving Multi-Level Optimization Problems with Dis

  6. 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…

  7. A new surgical technique for extensive exposure of the proximal humerus and shoulder.

    PubMed

    Puthezhath, Kishore; Puthur, Dominic K

    2013-11-01

    Different techniques have been described for surgical exposure of the shoulder and proximal humerus. However, the neurovascular and muscular anatomy in the proximity of the humerus precludes the use of a "safe" extensive approach. We here present a new technique for extensive exposure of the proximal humerus and shoulder for wide resection of tumors. By reflecting the deltoid with its origin as an osteomyocutaneous flap downwards and backwards, the entire shoulder, including the rotator cuff and proximal humerus, are exposed with minimal damage to the blood supply and function of the deltoid muscle. This approach, which is a logical combination of anterior, transacromial and deltoid splitting approaches, was used in 17 patients, 11 achieving satisfactory functional results. Our new surgical approach reduces intraoperative damage to the blood supply of the deltoid and results in better function of the shoulder postoperatively because both the powerful intermediate muscle fibers of the deltoid and its acromial origin remain intact.

  8. [Surgical technique of aortic valve replacement for small aortic annulus in elderly patients].

    PubMed

    Hata, T; Fujiwara, K; Furukawa, H; Tsushima, Y; Yoshitaka, H; Kuinose, M; Minami, H; Ishida, A; Tamura, K; Totsugawa, T; Kanemitsu, H; Ozawa, M

    2006-04-01

    Recent reports have shown that aortic valve replacement in elderly patients over 65 years with atherosclerotic aortic stenosis and a small aortic annulus is possible by using a small sized bioprosthesis (Carpentier-Edwards pericardial valve). Here we present out surgical technique. Firstly, the native calcified aortic valve was removed completely to gain total exposure of the surrounding aortic root and sinus of Valsalva like Bentall procedure. Secondly, a small sized bioprosthesis was implanted with intermittent noneverting mattress 2-0 sutures with spaghetti and small polytetrafluoroethylene (PTFE) felt. Aortic annulus is the dilated by inserting Hegar dilator sizing from 25 to 27 mm. Therefore, aortic valve replacement for small aortic annulus in intra- or supra-annular position should be easily accomplished. Good surgical results and hemodynamic state were achieved in 25 consecutive cases using this technique.

  9. Generating moment matching scenarios using optimization techniques

    SciTech Connect

    Mehrotra, Sanjay; Papp, Dávid

    2013-05-16

    An optimization based method is proposed to generate moment matching scenarios for numerical integration and its use in stochastic programming. The main advantage of the method is its flexibility: it can generate scenarios matching any prescribed set of moments of the underlying distribution rather than matching all moments up to a certain order, and the distribution can be defined over an arbitrary set. This allows for a reduction in the number of scenarios and allows the scenarios to be better tailored to the problem at hand. The method is based on a semi-infinite linear programming formulation of the problem that is shown to be solvable with polynomial iteration complexity. A practical column generation method is implemented. The column generation subproblems are polynomial optimization problems; however, they need not be solved to optimality. It is found that the columns in the column generation approach can be efficiently generated by random sampling. The number of scenarios generated matches a lower bound of Tchakaloff's. The rate of convergence of the approximation error is established for continuous integrands, and an improved bound is given for smooth integrands. Extensive numerical experiments are presented in which variants of the proposed method are compared to Monte Carlo and quasi-Monte Carlo methods on both numerical integration problems and stochastic optimization problems. The benefits of being able to match any prescribed set of moments, rather than all moments up to a certain order, is also demonstrated using optimization problems with 100-dimensional random vectors. Here, empirical results show that the proposed approach outperforms Monte Carlo and quasi-Monte Carlo based approaches on the tested problems.

  10. Generating moment matching scenarios using optimization techniques

    DOE PAGES

    Mehrotra, Sanjay; Papp, Dávid

    2013-05-16

    An optimization based method is proposed to generate moment matching scenarios for numerical integration and its use in stochastic programming. The main advantage of the method is its flexibility: it can generate scenarios matching any prescribed set of moments of the underlying distribution rather than matching all moments up to a certain order, and the distribution can be defined over an arbitrary set. This allows for a reduction in the number of scenarios and allows the scenarios to be better tailored to the problem at hand. The method is based on a semi-infinite linear programming formulation of the problem thatmore » is shown to be solvable with polynomial iteration complexity. A practical column generation method is implemented. The column generation subproblems are polynomial optimization problems; however, they need not be solved to optimality. It is found that the columns in the column generation approach can be efficiently generated by random sampling. The number of scenarios generated matches a lower bound of Tchakaloff's. The rate of convergence of the approximation error is established for continuous integrands, and an improved bound is given for smooth integrands. Extensive numerical experiments are presented in which variants of the proposed method are compared to Monte Carlo and quasi-Monte Carlo methods on both numerical integration problems and stochastic optimization problems. The benefits of being able to match any prescribed set of moments, rather than all moments up to a certain order, is also demonstrated using optimization problems with 100-dimensional random vectors. Here, empirical results show that the proposed approach outperforms Monte Carlo and quasi-Monte Carlo based approaches on the tested problems.« less

  11. Surgical repair of isolated triceps tendon rupture using a suture anchor technique: a case report

    PubMed Central

    MANCINI, FEDERICO; BERNARDI, GABRIELE; DE LUNA, VINCENZO; TUDISCO, COSIMO

    2016-01-01

    Rupture or avulsion of the distal triceps tendon is one of the least common tendon injuries. The most common clinical presentation of the injury is avulsion from the olecranon. The diagnosis of acute triceps tendon rupture may be missed and this can result in prolonged disability. We report the case of a 42-year-old man with isolated triceps rupture treated by an open surgical repair technique involving the use of bone suture anchors. PMID:28217662

  12. A Minimally Disruptive Surgical Technique for the Treatment of Osteitis Pubis in Athletes

    PubMed Central

    Hechtman, Keith S.; Zvijac, John E.; Popkin, Charles A.; Zych, Gregory A.; Botto-van Bemden, Angie

    2010-01-01

    Background: Multiple surgical procedures exist for the treatment of osteitis pubis: curettage of the symphysis joint, wedge resection, complete resection of the joint, placement of extraperitoneal retropubic synthetic mesh, and arthrodesis of the joint. However, a paucity of literature has reported long-term successful outcomes with the aforementioned approaches. Patients treated operatively have reported recalcitrant pain resulting from iatrogenic instability. The article presents the results of a conservative operative technique that avoids disruption of adjacent ligaments. Hypothesis: Preserving the adjacent ligamentous structures will allow competitive athletes to return to competition and activities of daily living free of iatrogenic pelvic instability and pain. Study Design: Case series. Methods: Four competitive athletes (2 professional and 2 collegiate football players) diagnosed with osteitis pubis were treated conservatively for a minimum of 6 months. Patients underwent surgical intervention upon failure to respond to nonoperative management. The degenerative tissue was resected, allowing only bleeding cancellous bone to remain while preserving the adjacent ligaments. An arthroscope was used to assist in curettage, allowing the debridement to be performed through a small incision in the anterior capsule. Results: The symptoms of all 4 patients resolved, and they returned to competitive athletics. This ligament-sparing technique provided a solid, stable repair and pain relief. Conclusion: This surgical technique preserves the adjacent ligamentous structures and allows competitive athletes to return to competition and activities of daily living free of pain and void of pelvic instability. Clinical Relevance: This technique is a surgical treatment option for athletes with osteitis pubis who fail conservative treatment. PMID:23015940

  13. Oncoplastic breast conserving surgery: a renaissance of anatomically-based surgical technique.

    PubMed

    Chen, C Y; Calhoun, K E; Masetti, R; Anderson, B O

    2006-10-01

    Using oncoplastic surgical techniques for breast preservation, breast surgeons can achieve widened surgical margins at the same time that the shape and appearance of the breast is preserved and sometimes rejuvenated. Oncoplastic surgical resection is designed to follow the cancer's contour, which generally follows the segmental anatomy of the breast, which has been well understood since the mid 19th century because of pioneering anatomic studies performed by Sir Astley Paston Cooper. The quadrantectomy, developed by Veronesi and colleagues in the 1970's, follows these same anatomic principles of wide segmental resection. The more surgically narrow lumpectomy as popularized in the U.S. uses a smaller, scoop-like non-anatomic resection of cancer. With negative surgical margins, the lumpectomy is equivalent to the quadrantectomy in achieving the goals of breast conservation as measured by local recurrence and survival. However, the lumpectomy is less versatile for resection of larger cancers, and can be more prone to creating suboptimal cosmetic defects. Cancers with large in situ components can be particularly problematic for resection with the standard lumpectomy, when they extend both centrally toward the nipple and peripherally to distal terminal ductulo-lobular units, which typically occur in a pie-shaped segmental distribution. Ductal segments, each of which ultimately drains to a single major lactiferous sinus at the nipple, vary in size and depth in the breast. Breast surgeons should carefully evaluate the cancer distribution and extent in the breast before operation. A combination of imaging methods (mammography with magnification views, ultrasonography, magnetic resonance imaging [MRI], or all) may yield the best estimates of overall tumor extent. Multiple bracketing wires afford the greater help to complete surgical excision. Those tumors with segmental spreading are best excised by oncoplastic resections according to their distribution.

  14. 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.

  15. SEVERE VALGUS DEFORMITY OF THE KNEE: DESCRIPTION OF NEW SURGICAL TECHNIQUE FOR ITS CORRECTION

    PubMed Central

    da Silva, Robson Rocha; Matos, Marcos Almeida; Pimentel, Maurício; Martins, Bruno Jacomeli; Oliveira, Rafael Valadares

    2015-01-01

    Varus supracondylar osteotomy of the femur is the established procedure for treating painful knees that present lateral arthrosis and valgus deformity. In descriptions of the conventional surgical techniques, there are divergences regarding the location, access route, correction level, fixation type and area for synthesis insertion. This is most evident in cases of severe valgus with angles greater than 30° and distal femoral deformation, in association with hypoplasia of the lateral condyle. The authors describe a new surgical technique for distal femoral osteotomy, based on anatomical and geometrical criteria, which was developed in their clinic for treating severe valgus cases, and they present one of the cases treated. In the new technique, the wedge to be surgically resected has an oblique direction and the format of an isosceles triangle. This new proposal thus seeks to resolve problems that have been presented in such cases, through enabling valgus correction without causing any new deformity of the distal femur. Good cortical bone contact is promoted, and application of a stable synthesis system is made easier. However, the age limits for such patients and the degree of knee arthrosis that might contraindicate this procedure remain unknown. Hence, a larger sample and longer follow-up for operated cases are required. PMID:27042630

  16. Primary cerebral echinoccocosis in a child: Case report – Surgical technique, technical pitfalls, and video atlas

    PubMed Central

    Altibi, Ahmed M. A.; Qarajeh, Raed A. H.; Belsuzarri, Telmo A. B.; Maani, Walid; Kanaan, Tareq M. A.

    2016-01-01

    Background: Hydatid disease is a life-threatening parasitic infestation caused by Echinococcus granulosus. Infection with E. granulosus typically results in the formation of hydatid cysts in the liver, lungs, kidney, and spleen. Primary intracranial hydatid cyst disease is extremely rare. Here, we are reporting an unusual case of Echinococcus, where the only identifiable lesion was a hydatid cyst in the brain without liver or lung involvement. We are also providing a description for the surgical technique used to remove the cyst, highlighting the possible surgical pitfalls. Case Description: The patient is a 13-year-old male with a history of progressive headache for 1 month. Intracranial hydatid cyst was suspected based on computed tomography and magnetic resonance imaging findings. The cyst was delivered without rupture using hydrostatic dissection (Dowling's technique), and pathological analysis confirmed the diagnosis. Postoperatively, the patient showed marked neurological improvement and all signs and symptoms resolved. Conclusion: Intracranial hydatid cyst is very rare. Nevertheless, it should always be considered as a differential diagnosis in cerebral cystic lesions, especially in children. The surgical technique used to remove the cyst appears to be safe. However, several precautions must be applied intraoperatively to avoid the catastrophe of cyst rupture. PMID:27999716

  17. Advances in Surgical Reconstructive Techniques in the Management of Penile, Urethral, and Scrotal Cancer.

    PubMed

    Bickell, Michael; Beilan, Jonathan; Wallen, Jared; Wiegand, Lucas; Carrion, Rafael

    2016-11-01

    This article reviews the most up-to-date surgical treatment options for the reconstructive management of patients with penile, urethral, and scrotal cancer. Each organ system is examined individually. Techniques and discussion for penile cancer reconstruction include Mohs surgery, glans resurfacing, partial and total glansectomy, and phalloplasty. Included in the penile cancer reconstruction section is the use of penile prosthesis in phalloplasty patients after penectomy, tissue engineering in phallic regeneration, and penile transplantation. Reconstruction following treatment of primary urethral carcinoma and current techniques for scrotal cancer reconstruction using split-thickness skin grafts and flaps are described.

  18. "The Superficial Quad Technique" for Medial Patellofemoral Ligament Reconstruction: The Surgical Video Technique.

    PubMed

    Goyal, Deepak

    2015-10-01

    With the introduction of the superficial quad technique, there has been a recent revival of interest in the quadriceps tendon as a graft choice for medial patellofemoral ligament (MPFL) reconstruction. The superficial quad technique has many anatomic advantages because the length, breadth, and thickness of the graft are similar to those of the native MPFL; moreover, the graft provides a continuous patellar attachment at the superior half of the medial border of the patella. The technique requires neither a patellar bony procedure nor patellar hardware. Biomechanically, the mean strength and stiffness of the graft are very similar to those of the native MPFL. The anatomic and biomechanical advantages depend on correct identification of the anatomic superficial lamina of the quadriceps tendon; hence the correct harvesting technique for the superficial lamina is crucial. Various sub-techniques for harvesting the quadriceps graft have emerged recently, such as superficial strip, pedicled, or partial graft harvesting; these can create confusion for surgeons. Additional confusion related to the preparation and fixation of the graft should also be addressed to avoid any potential complications. A step-by-step video of the superficial quad technique is presented, covering the exact dissection of the graft material and its preparation, delivery, and fixation.

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

    PubMed

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

    2017-04-03

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

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

    PubMed

    Junqueira, Marina Azevedo; Cunha, Nayara Nery Oliveira; Costa e Silva, Lidiane Lucas; Araújo, Leandro Borges; Moretti, Ana Beatriz Silveira; Couto Filho, Carlos Eduardo Gomes; Sakai, Vivien Thiemy

    2014-06-01

    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.

  1. 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

  2. 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

  3. A new technique for feeding dogs with a congenital cleft palate for surgical research.

    PubMed

    Martínez-Sanz, Elena; Casado-Gómez, Inmaculada; Martín, Concepción; López-Gordillo, Yamila; González, Pablo; Rodríguez-Bobada, Cruz; Paradas, Irene; González-Meli, Beatriz; Maldonado, Estela; Maestro, Carmen; Prados, Juan Carlos; Martínez-Álvarez, Concepción

    2011-04-01

    In humans, cleft palate (CP) is one of the most common malformations. Although surgeons use palatoplasty to close CP defects in children, its consequences for subsequent facial growth have prompted investigations into other novel surgical alternatives. The animal models of CP used to evaluate new surgical treatments are frequently obtained by creating surgically induced clefts in adult dogs. This procedure has been ethically criticized due to its severity and questionable value as an animal model for human CP. Dogs born with a congenital CP would be much better for this purpose, provided they developed CP at a sufficient rate and could be fed. Up until now, feeding these pups carried the risk of aspiration pneumonia, while impeding normal suckling and chewing, and thus compromising orofacial growth. We developed a technique for feeding dog pups with CP from birth to the time of surgery using two old Spanish pointer dog pups bearing a complete CP. This dog strain develops CP in 15-20% of the offspring spontaneously. Custom-made feeding teats and palatal prostheses adapted to the pups' palates were made from thermoplastic plates. This feeding technique allowed lactation, eating and drinking in the pups with CP, with only sporadic rhinitis. To determine whether the use of this palatal prosthesis interferes with palatal growth, the palates of three littermate German shorthaired pointer pups without CP, either wearing or not wearing (controls) the prosthesis, were measured. The results showed that the permanent use of this prosthesis does not impede palatal growth in the pups.

  4. 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.

  5. Management of surgical splenorenal shunt-related hepatic myelopathy with endovascular interventional techniques.

    PubMed

    Wang, Mao-Qiang; Liu, Feng-Yong; Duan, Feng

    2012-12-21

    We present a case with hepatic myelopathy (HM) due to a surgical splenorenal shunt that was successfully treated by endovascular interventional techniques. A 39-year-old man presented with progressive spastic paraparesis of his lower limbs 14 mo after a splenorenal shunt. A portal venogram identified a widened patent splenorenal shunt. We used an occlusion balloon catheter initially to occlude the shunt. Further monitoring of the patient revealed a decrease in his serum ammonia level and an improvement in leg strength. We then used an Amplatzer vascular plug (AVP) to enable closure of the shunt. During the follow up period of 7 mo, the patient experienced significant clinical improvement and normalization of blood ammonia, without any complications. Occlusion of a surgically created splenorenal shunt with AVP represents an alternative therapy to surgery or coil embolization that can help to relieve shunt-induced HM symptoms.

  6. Computer-assisted surgical techniques evaluated with wound-healing-impaired animal model

    NASA Astrophysics Data System (ADS)

    Reinisch, Lou; West, Courtney; Rivas, Mike; Patil, Yash; Ossoff, Robert H.

    1996-04-01

    As part of our computer assisted surgical techniques (CAST) program, we use computers to assist in the guidance of surgical lasers. The computer helps to create laser incisions with minimal widths, a reduction of collateral thermal damage, and regulates the rate of tissue ablation. Previous studies have compared laser incisions under manual control to incisions made with the CAST system. These studies were carried out with healthy animals. In this study, we compare the manual and CAST laser incisions on rats with induced diabetes. The diabetic rats have impaired wound healing and make a better model for our wound healing studies. Cutaneous incisions were made on the dorsal pelt using a carbon dioxide laser. The incisions were sutured and allowed to heal for 3, 7, 14, and 21 days. Wounds were analyzed histologically and with tensiometry. We have found definite advantages to the CAST program.

  7. Minimally invasive selective osteotomy of the knee: A new surgical technique.

    PubMed

    Leon, H O; Blanco, C E; Guthrie, T B

    2001-05-01

    We present a simple surgical technique created by the authors to address degenerative chondral lesions of the knee and its application in a limited prospective case series. The technique assumes the concept of beneficial epiphyseal changes caused by disruption of the subchondral bone in improving symptoms, as with drilling, microfracture, periarticular osteotomy, and other invasive procedures. Minimally invasive selective osteotomy (MISO) is an expansion of the arthroscopic treatment of the knee, specifically targeting symptomatic lesions with minimal additional trauma and cost, while avoiding disruption of the articular surface of the subchondral bone. The technique involves a mimimal access approach with selective saw cuts placed with a 1-cm oscillating blade parallel to the joint surface 1 to 1.5 cm deep to identified lesions. The technique does not address malalignment but can address lesions not addressed by classic osteotomies and, as such, may be combined with other corrective alignment procedures as necessary. We present the results of MISO of the knee in a case series of 62 outpatients carried out at the Orthopaedic Division of the Clinical and Surgical Hermanos Ameijeiras Hospital in Havana, Cuba. At 2-year follow-up, there was improvement of symptoms without significant complications.

  8. Surgical technique in cadaveric donors for partial hand allotransplant in patients with rheumatoid arthritis.

    PubMed

    Iglesias, M; Butrón, P; Santander-Flores, S; Ricaño-Enciso, D; Negrete-Najar, J P; Pérez-Monzó, M F; González-Chávez, A; González-Chávez, M; de Rienzo-Madero, B; Hamdan-Pérez, N

    2010-01-01

    For patients with severe hand deformities due to rheumatoid arthritis, we propose an allotransplantation of an osteomyotendinose structure (OMTS), preserving the recipient's skin and sensory nerves. Our objective was to develop the surgical technique in a 10 cadavers, five as donors and five as recipients. The donor's hand was 10% to 15% smaller than the recipient's. Dissections were performed by two surgical teams under magnification. In the donor, the OMTS was procured at the distal third of the forearm, maintaining the integrity of the arterial system, with its concomitant veins and motor branches of the median and ulnar nerves, leaving the skin envelope. In the recipient, the OMTS was removed, taking care to preserve the cutaneous cover with the digital arteries in continuity with the superficial palmar arch and radial and ulnar arteries. Also, the digital nerves were maintained in the skin flap, in continuity with the median and ulnar nerves. Their motor branches were divided after emergence from the main nerves. The superficial dorsal veins and radial nerve were kept adhered to the cutaneous cover. Then, the donor OMTS was placed within the recipient cutaneous flap; all the anatomic structures were repaired. The average surgical time was 780 minutes. Methylene blue was present in the digital arteries. There were no difficulties in the anatomic repair. The surgical technique is quite laborious, especially the dissection of the recipient interdigital spaces. Due to the requirement for arterial system integrity, the cutaneous flap must be viable. Also, the allotransplanted OMTS has all necessary conditions to obtain good tissue perfusion for subsequent function. Procurement without skin permits a greater opportunity to find donors, and greater social and personal acceptance by the recipient.

  9. Acceleration techniques in the univariate Lipschitz global optimization

    NASA Astrophysics Data System (ADS)

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

    2016-10-01

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

  10. 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.

  11. 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.

  12. [Surgical reconstruction of maxillary defects using a computer-assisted techniques].

    PubMed

    Zhang, W B; Yu, Y; Wang, Y; Liu, X J; Mao, C; Guo, C B; Yu, G Y; Peng, X

    2017-02-18

    The maxilla is the most important bony support of the mid-face skeleton and is critical for both esthetics and function. Maxillary defects, resulting from tumor resection, can cause severe functional and cosmetic deformities. Furthermore, maxillary reconstruction presents a great challenge for oral and maxillofacial surgeons. Nowadays, vascularized composite bone flap transfer has been widely used for functional maxillary reconstruction. In the last decade, we have performed a comprehensive research on functional maxillary reconstruction with free fibula flap and reported excellent functional and acceptable esthetic results. However, this experience based clinical procedure still remainssome problems in accuracy and efficiency. In recent years, computer assisted techniques are now widely used in oral and maxillofacial surgery. We have performed a series of study on maxillary reconstruction with computer assisted techniques. The computer assisted techniques used for maxillary reconstruction mainly include: (1) Three dimensional (3D) reconstruction and tumor mapping: providing a 3D view of maxillary tumor and adjacent structures and helping to make the diagnosis of maxillary tumor accurate and objective; (2) Virtual planning: simulating tumor resection and maxillectomy as well as fibula reconstruction on the computer, so that to make an ideal surgical plan; (3) 3D printing: producing a 3D stereo model for prebending individualized titanium mesh and also providing template or cutting guide for the surgery; (4) Surgical navigation: the bridge between virtual plan and real surgery, confirming the virtual plan during the surgery and guarantee the accuracy; (5) Computer assisted analyzing and evaluating: making a quantitative and objective of the final result and evaluating the outcome. We also performed a series of studies to evaluate the application of computer assisted techniques used for maxillary reconstruction, including: (1) 3D tumor mapping technique for accurate

  13. 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.

  14. 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

  15. Surgical approach to right colon cancer: From open technique to robot. State of art.

    PubMed

    Fabozzi, Massimiliano; Cirillo, Pia; Corcione, Francesco

    2016-08-27

    This work is a topic highlight on the surgical treatment of the right colon pathologies, focusing on the literature state of art and comparing the open surgery to the different laparoscopic and robotic procedures. Different laparoscopic procedures have been described for the treatment of right colon tumors: Totally laparoscopic right colectomy, laparoscopic assisted right colectomy, laparoscopic facilitated right colectomy, hand-assisted right colectomy, single incision laparoscopic surgery colectomy, robotic right colectomy. Two main characteristics of these techniques are the different type of anastomosis: Intracorporeal (for totally laparoscopic right colectomy, single incision laparoscopic surgery colectomy, laparoscopic assisted right colectomy and robotic technique) or extracorporeal (for laparoscopic assisted right colectomy, laparoscopic facilitated right colectomy, hand-assisted right colectomy and open right colectomy) and the different incision (suprapubic, median or transverse on the right side of abdomen). The different laparoscopic techniques meet the same oncological criteria of radicalism as the open surgery for the right colon. The totally laparoscopic right colectomy with intracorporeal anastomosis and even more the single incision laparoscopic surgery colectomy, remain a technical challenge due to the complexity of procedures (especially for the single incision laparoscopic surgery colectomy) and the particular right colon vascular anatomy but they seem to have some theoretical advantages compared to the other laparoscopic and open procedures. Data reported in literature while confirming the advantages of laparoscopic approach, do not allow to solve controversies about which is the best laparoscopic technique (Intracorporeal vs Extracorporeal Anastomosis) to treat the right colon cancer. However, the laparoscopic techniques with intracorporeal anastomosis for the right colon seem to show some theoretical advantages (functional, technical

  16. 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.

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

    PubMed

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

    2006-01-01

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

  18. Image guidance could aid performance of atraumatic cochlear implantation surgical techniques

    NASA Astrophysics Data System (ADS)

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

    2013-03-01

    It is widely believed that major factors in achieving atraumatic insertion of the electrode array into the cochlea in cochlear implant (CI) surgery include amount of tissue resection, selection of the entry point, and angle of insertion. Our group is interested in developing an image guidance (IG) system for electrode insertion if IG can improve outcomes. Thus, in this work we conducted the first study evaluating whether IG could aid atraumatic electrode insertion. To do this, we measured the performance of experienced surgeons when tasked to perform cochleostomy resection and to select CI insertion trajectories in virtual 3D surgical field-of-view simulation software. This software, which simulates views through the surgical microscope, was designed to allow a user to manually perform cochleostomy resection and to select a preferred insertion trajectory in one of two modes: (a) where the traditional approach is simulated and sub-surface anatomy is not visible; and (b) where an IG approach is simulated and the surgical view is augmented with rendering of subsurface intra-cochlear structures. We used this software to compare two surgeons' performance in selecting insertion trajectories with and without IG. Our results show that when using virtual IG, both surgeons could choose insertion trajectories with less variability, select higher quality insertion trajectories, and create the cochleostomy with substantially less tissue resection. These results suggest that IG could indeed aid performance of atraumatic cochlear implantation techniques.

  19. 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

  20. [A new surgical method: lengthening of jaw bone by means of distraction technique].

    PubMed

    Nord, P G

    2001-05-30

    Callus distraction, or distraction osteogenesis as the method also is called, is a new surgical technique which makes it possible to create new bone by bone elongation. The method was originally used in orthopedic surgery to extend long bones but has subsequently proved useful for extending the mandible as well as other bones in the facial skeleton. By callus distraction, it is now possible to treat severe jaw anomalies and also to treat bone defects in the jaws without bone transplantation. This article describes the biological background to the method and the basic principles that must be observed for successful results. The treatment of four patients illustrates the method.

  1. Above-elbow (supracondylar) arm transplantation: clinical considerations and surgical technique.

    PubMed

    Shores, Jaimie T; Higgins, James P; Lee, W P Andrew

    2013-12-01

    Vascularized composite allotransplantation, also known as "Reconstructive Transplantation" is becoming more commonplace worldwide. Hand and upper extremity transplantation make up the majority of clinical vascularized composite allotransplantation cases performed so far. As success with reconstructive transplantation becomes more common, more challenging examples of limb loss are being addressed, including above-elbow, or "supracondylar" upper extremity transplants. Although very few of these cases have been performed worldwide, the authors' experience includes the only 2 cases performed in the United States at the time of this report. This article will discuss indications, challenges, surgical technique, expected outcomes, and alternative technologies for treatment of limb loss above the elbow.

  2. CORONIS - International study of caesarean section surgical techniques: the follow-up study

    PubMed Central

    2013-01-01

    Background The CORONIS Trial was a 2×2×2×2×2 non-regular, fractional, factorial trial of five pairs of alternative caesarean section surgical techniques on a range of short-term outcomes, the primary outcome being a composite of maternal death or infectious morbidity. The consequences of different surgical techniques on longer term outcomes have not been well assessed in previous studies. Such outcomes include those related to subsequent pregnancy: mode of delivery; abnormal placentation (e.g. accreta); postpartum hysterectomy, as well as longer term pelvic problems: pain, urinary problems, infertility. The Coronis Follow-up Study aims to measure and compare the incidence of these outcomes between the randomised groups at around three years after women participated in the CORONIS Trial. Methods/Design This study will assess the following null hypotheses: In women who underwent delivery by caesarean section, no differences will be detected with respect to a range of long-term outcomes when comparing the following five pairs of alternative surgical techniques evaluated in the CORONIS Trial: 1. Blunt versus sharp abdominal entry 2. Exteriorisation of the uterus for repair versus intra-abdominal repair 3. Single versus double layer closure of the uterus 4. Closure versus non-closure of the peritoneum (pelvic and parietal) 5. Chromic catgut versus Polyglactin-910 for uterine repair The outcomes will include (1) women’s health: pelvic pain; dysmenorrhoea; deep dyspareunia; urinary symptoms; laparoscopy; hysterectomy; tubal/ovarian surgery; abdominal hernias; bowel obstruction; infertility; death. (2) Outcomes of subsequent pregnancies: inter-pregnancy interval; pregnancy outcome; gestation at delivery; mode of delivery; pregnancy complications; surgery during or following delivery. Discussion The results of this follow-up study will have importance for all pregnant women and for health professionals who provide care for pregnant women. Although the results will

  3. Surgical treatment of Madelung disease by the Sauvé-Kapandji technique.

    PubMed

    Angelini, L C; Leite, V M; Faloppa, F

    1996-01-01

    The Madelung deformity, a congenital alteration of growth in the distal radial epiphysis, becomes evident during adolescence, producing serious esthetic and functional disturbances. From 1982 to 1991, 15 patients ranging from 16 to 23 years old, suffering from Madelung deformity were operated by the Sauvé-Kapandji surgical technique (a pseudarthrosis is created on the ulna and an arthrodesis on the distal radio ulnar joint). The esthetic appearance and grip strength were improved. Pain was eliminated and the incidence of complications was very low.

  4. Total ankle replacement using HINTEGRA, an unconstrained, three-component system: surgical technique and pitfalls.

    PubMed

    Barg, Alexej; Knupp, Markus; Henninger, Heath B; Zwicky, Lukas; Hintermann, Beat

    2012-12-01

    Total ankle replacement (TAR) has become a valuable treatment option in patients with end-stage ankle osteoarthritis. One popular 3-component system, the HINTEGRA TAR, is an unconstrained system that provides inversion-eversion stability. More natural biomechanics of the replaced ankle may be expected when anatomic considerations drive prosthesis design. The HINTEGRA prosthesis includes 2 anatomically contoured metal components and a polyethylene insert, providing axial rotation and physiologic flexion-extension mobility. This article describes the HINTEGRA TAR design and surgical technique. Use of the prosthesis for complex hindfoot reconstruction in patients with an osteoarthritic, varus, or valgus ankle deformity is described.

  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.

  6. “Central” Quadriceps Tendon Harvest With Patellar Bone Plug: Surgical Technique Revisited

    PubMed Central

    Scully, William F.; Wilson, David J.; Arrington, Edward D.

    2013-01-01

    The objective of this article is to review the surgical technique for quadriceps tendon graft harvest while highlighting an additional technical note that has not been previously emphasized. The quadriceps tendon typically inserts eccentrically on the superior pole of the patella. By shifting the soft-tissue harvest to a location just off the medial edge of the tendon, the adjoining patellar bone plug will be centered on the superior pole of the patella, reducing the risk of an iatrogenic patellar fracture. PMID:24400194

  7. Barriers to the optimal rehabilitation of surgical cancer patients in the managed care environment: an administrator's perspective.

    PubMed

    Germain, Pamela

    2007-04-01

    Ensuring that surgical cancer patients obtain optimal rehabilitation care (defined here as all care provided post-operatively following cancer surgery) can be challenging because of the fragmented nature of the U.S. healthcare delivery and payment systems. In the managed care environment, surgical cancer patients' access to rehabilitation care is likely to vary by type of health insurance plan, by setting, by type of provider, and by whether care is provided in-network or out-of-network. The author of this article, who negotiates managed care contracts for the Roswell Park Cancer Institute (RPCI), gives examples of strategies used with some success by RPCI to collaborate with local payers to ensure that surgical cancer patients get optimal rehabilitation care, especially as they make the transition from hospital to outpatient care. She suggests that further collaborations of healthcare providers, payers, consumers, and policymakers are needed to help ensure optimal rehabilitation care for surgical cancer patients.

  8. Microsurgical subinguinal varicocelectomy in children, adolescents, and adults: surgical anatomy and anatomically justified technique.

    PubMed

    Mirilas, Petros; Mentessidou, Anastasia

    2012-01-01

    Microsurgical varicocelectomy has become the gold standard in adults because of low recurrence and postoperative hydrocele rates; it is increasingly applied in children and adolescents. This review aims to provide the surgeon with the necessary surgical anatomy of the spermatic cord and with a step-by-step, anatomically justified description of technique, toward clearer comprehension and improved application. The anatomic compartments of the spermatic cord are delineated by the external and internal spermatic fasciae. Venous drainage of testis-epididymis is accomplished by the internal spermatic, deferential, and external spermatic (cremasteric) veins. All 3 anastomose at the caudal pole of testis, and then via gubernacular veins with the posterior scrotal veins. Another anastomosis exists between a cremasteric branch and anterior scrotal veins, which gives the external pudendal vein. Subinguinal approach offers access to varicose spermatic veins and collaterals. Use of surgical microscope offers identification of small veins, preservation of arteries, lymphatics, and nerves, and appreciation of spermatic cord fasciae, which permits the development of two surgical planes. In the surgical plane of internal spermatic vessels, internal spermatic veins are ligated, whereas the testicular artery and innervation, as well as lymphatics, are preserved. In the plane of cremasteric vessels and vas, cremasteric veins are ligated, whereas the cremasteric artery, vas deferens and its vasculature, lymphatics, and the genital branch of genitofemoral nerve are preserved. Delivery of the testis to ligate gubernacular veins is at the discretion of the surgeon. Finally, venous return is effected by deferential and scrotal veins, or, when gubernacular veins are ligated, by deferential veins only.

  9. Surgical technique for single-port laparoscopy in huge ovarian tumors: SW Kim's technique and comparison to laparotomy

    PubMed Central

    Kim, Jeong Sook; Lee, In Ok; Eoh, Kyung Jin; Chung, Young Shin; Lee, Inha; Lee, Jung-Yun; Nam, Eun Ji; Kim, Sunghoon; Kim, Young Tae

    2017-01-01

    Objective This study aimed to introduce a method to remove huge ovarian tumors (≥15 cm) intact with single-port laparoscopic surgery (SPLS) using SW Kim's technique and to compare the surgical outcomes with those of laparotomy. Methods Medical records were retrospectively reviewed for patients who underwent either SPLS (n=21) with SW Kim's technique using a specially designed 30×30-cm2-sized 3XL LapBag or laparotomy (n=22) for a huge ovarian tumor from December 2008 to May 2016. Perioperative surgical outcomes were compared. Results In 19/21 (90.5%) patients, SPLS was successfully performed without any tumor spillage or conversion to multi-port laparoscopy or laparotomy. There was no significant difference in patient characteristics, including tumor diameter and total operation time, between both groups. The postoperative hospital stay was significantly shorter for the SPLS group than for the laparotomy group (median, 2 [1 to 5] vs. 4 [3 to 17] days; P<0.001). The number of postoperative general diet build-up days was also significantly shorter for the SPLS group (median, 1 [1 to 4] vs. 3 [2 to 16] days; P<0.001). Immediate post-operative pain score was lower in the SPLS group (median, 2.0 [0 to 8] vs. 4.0 [0 to 8]; P=0.045). Patient-controlled anesthesia was used less in the SPLS group (61.9% vs. 100%). Conclusion SPLS was successful in removing most large ovarian tumors without rupture and showed quicker recovery and less immediate post-operative pain in comparison to laparotomy. SPLS using SW Kim's technique could be a feasible solution to removing huge ovarian tumors. PMID:28344959

  10. Optimization of detector positioning in the radioactive particle tracking technique.

    PubMed

    Dubé, Olivier; Dubé, David; Chaouki, Jamal; Bertrand, François

    2014-07-01

    The radioactive particle tracking (RPT) technique is a non-intrusive experimental velocimetry and tomography technique extensively applied to the study of hydrodynamics in a great variety of systems. In this technique, arrays of scintillation detector are used to track the motion of a single radioactive tracer particle emitting isotropic γ-rays. This work describes and applies an optimization strategy developed to find an optimal set of positions for the scintillation detectors used in the RPT technique. This strategy employs the overall resolution of the detectors as the objective function and a mesh adaptive direct search (MADS) algorithm to solve the optimization problem. More precisely, NOMAD, a C++ implementation of the MADS algorithm is used. First, the optimization strategy is validated using simple cases with known optimal detector configurations. Next, it is applied to a three-dimensional axisymmetric system (i.e. a vertical cylinder, which could represent a fluidized bed, bubble column, riser or else). The results obtained using the optimization strategy are in agreement with what was previously recommended by Roy et al. (2002) for a similar system. Finally, the optimization strategy is used for a system consisting of a partially filled cylindrical tumbler. The application of insights gained by the optimization strategy is shown to lead to a significant reduction in the error made when reconstructing the position of a tracer particle. The results of this work show that the optimization strategy developed is sensitive to both the type of objective function used and the experimental conditions. The limitations and drawbacks of the optimization strategy are also discussed.

  11. 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

  12. Optimizing Patient Preparation and Surgical Experience Using eHealth Technology

    PubMed Central

    Forshaw, Kristy; Carey, Mariko; Robinson, Sancha; Kerridge, Ross; Proietto, Anthony; Sanson-Fisher, Rob

    2015-01-01

    With population growth and aging, it is expected that the demand for surgical services will increase. However, increased complexity of procedures, time pressures on staff, and the demand for a patient-centered approach continue to challenge a system characterized by finite health care resources. Suboptimal care is reported in each phase of surgical care, from the time of consent to discharge and long-term follow-up. Novel strategies are thus needed to address these challenges to produce effective and sustainable improvements in surgical care across the care pathway. The eHealth programs represent a potential strategy for improving the quality of care delivered across various phases of care, thereby improving patient outcomes. This discussion paper describes (1) the key functions of eHealth programs including information gathering, transfer, and exchange; (2) examples of eHealth programs in overcoming challenges to optimal surgical care across the care pathway; and (3) the potential challenges and future directions for implementing eHealth programs in this setting. The eHealth programs are a promising alternative for collecting patient-reported outcome data, providing access to credible health information and strategies to enable patients to take an active role in their own health care, and promote efficient communication between patients and health care providers. However, additional rigorous intervention studies examining the needs of potential role of eHealth programs in augmenting patients’ preparation and recovery from surgery, and subsequent impact on patient outcomes and processes of care are needed to advance the field. Furthermore, evidence for the benefits of eHealth programs in supporting carers and strategies to maximize engagement from end users are needed. PMID:26330206

  13. Activity analysis: measurement of the effectiveness of surgical training and operative technique.

    PubMed

    Shepherd, J P; Brickley, M

    1992-11-01

    All surgical procedures are characterised by a sequence of steps and instrument changes. Although surgical efficiency and training in operative technique closely relate to this process, few studies have attempted to analyse it quantitatively. Because efficiency is particularly important in day surgery and lower third molar removal is a high-volume procedure, the need for which is responsible for particularly long waiting-lists in almost all UK health regions, this operation was selected for evaluation. A series of 80 consecutive procedures, carried out for 43 day-stay patients under general anaesthesia by seven junior staff (senior house officers and registrars: 39 procedures) and four senior staff (senior registrars and consultants: 41 procedures) were analysed. Median operating time for procedures which required retraction of periosteum was 9.5 min (range 2.7-23.3 min). Where these steps were necessary, median time for incision was 25 s (range 10-90 s); for retraction of periosteum, 79 s (range 5-340 s); for bone removal, 118 s (range 10-380 s); for tooth excision, 131 s (range 10-900 s); for debridement, 74 s (range 5-270 s); and for suture, 144 s (range 25-320 s). Junior surgeons could be differentiated from senior surgeons on the basis of omission, repetition and duration of these steps. Juniors omitted retraction of periosteum in 10% of procedures (seniors 23%) and suture in 13% (seniors 32%). Juniors repeated steps in 47% of operations; seniors, 14%. Junior surgeons took significantly more time than senior surgeons for incision, bone removal and tooth excision. No significant differences between junior and senior surgeons were found in relation to the incidence of altered lingual and labial sensation at 7 days. It was concluded that activity analysis may be a useful measure of the effectiveness of surgical training and the efficiency of operative technique.

  14. 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

  15. 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.

  16. Three-dimensional evaluation of surgical techniques in neonates with orofacial cleft

    PubMed Central

    Carrara, Cleide Felício Carvalho; Ambrosio, Eloá Cristina Passucci; Mello, Bianca Zeponi Fernandes; Jorge, Paula Karine; Soares, Simone; Machado, Maria Aparecida Andrade Moreira; Oliveira, Thais Marchini

    2016-01-01

    Background: Individuals with cleft lip and palate have many anatomic and functional alterations compromising esthetics, hearing, speech, occlusion, and development/craniofacial growth. The rehabilitative treatment of these patients is very challenging and starts at birth aiming at the best treatment for all functional demands. This study aimed to evaluate the dimensional alterations of the dental arches of neonates with cleft lip and palate after two different primary surgical techniques. Materials and Methods: The sample comprised 114 digital models of children aged from 3 to 36 months, with unilateral complete cleft lip and palate divided into two groups. Two different phases were evaluated: precheiloplasty and 1 year after palatoplasty. The evaluation was performed through the digital models of each child obtained by scanning digitalization (3D Scanner). Dental arches measurements were accomplished through Appliance Designer software. The following measurements were assessed: dental arch area, anterior amplitude of the cleft, total length of dental arch, intercanine distance, and intertuberosity distance. t-test was applied to compare differences between groups. Results: No statistically significant differences were observed between groups at precheiloplasty phase. At 1 year after palatoplasty, the groups differed in the total length of dental arch (P = 0.002), with greater values for Group I. Conclusion: This study suggests that the results of the different surgical techniques may alter the growth and development of the dental arches of neonates with cleft lip and palate. PMID:28299266

  17. Surgical Treatment of Iatrogenic Ventral Glottic Stenosis Using a Mucosal Flap Technique

    PubMed Central

    Barnett, Timothy P.; O'Leary, John Mark; Dixon, Padraic M.

    2016-01-01

    Objective To describe a novel surgical technique for correcting postoperative ventral glottic stenosis (cicatrix or web formation) and the outcome in 2 Thoroughbred racehorses. Study Design Retrospective case report. Animals Thoroughbreds diagnosed with ventral glottic stenosis (n=2). Methods Horses presenting with iatrogenic ventral glottic stenosis and resultant exercise intolerance and abnormal exercise‐related noise were anesthetized and a midline sagittal skin incision was made over the ventral larynx and between the sternohyoideus muscles overlying the cricothyroid notch. The cricothyroid ligament, attached laryngeal cicatrix, and overlying mucosa were sagittally sectioned at the dorsal aspect of the cicatrix on the left side. The laryngeal mucosa, cicatrix, and underlying cricothyroid ligament immediately rostral and caudal to the cicatrix were sectioned in a medial (axial) direction as far as the right side of the cricothyroid notch. After resection of the majority of the attached cicatrix tissue, the residual mucosal flap (attached to the right side of the larynx) was reflected ventrally and sutured to the attachment of the cricothyroid ligament on the right side of the cricothyroid notch, creating an intact mucosal layer on the right side of the ventral larynx. Results Both horses had good intralaryngeal wound healing with minimal redevelopment of ventral glottic stenosis at 5 and 9 months postoperatively and were successfully returned to racing with complete absence of abnormal respiratory noise. Conclusion The unique laryngeal anatomy of horses, with a cartilage‐free ventral laryngeal area (cricothyroid notch), allowed the use of this novel surgical technique to successfully treat ventral glottic stenosis. PMID:27013024

  18. A novel technique for three-dimensional reconstruction for surgical simulation around the craniocervical junction region.

    PubMed

    Liu, Guang-Jiu; Zhang, Shao-Xiang; Qiu, Ming-Guo; Tan, Li-Wen; Li, Qi-Yu; Li, Kai

    2011-01-01

    Performing surgeries on the craniocervical junction presents a technical challenge for operating surgeons. Three-dimensional (3D) reconstruction and surgical simulation have improved the efficacy and success rate of surgeries. The aim of this study was to create a 3D, digitized visible model of the craniocervical junction region to help realize accurate simulation of craniocervical surgery on a graphic workstation. Transverse sectional anatomy data for the study were chosen from the first Chinese visible human. Manual axial segmentation of the skull base, cervical spine, cerebellum, vertebral artery, internal carotid artery, sigmoid sinus, internal jugular vein, brain stem, and spinal cord were carried out by using Photoshop software. The segmented structures were reconstructed in 3 dimensions with surface and volume rendering to accurately display 3D models spatially. In contrast to conventional 3D reconstruction techniques that are based on computed tomography and magnetic resonance imaging Digital Imaging and Communications in Medicine (DICOM) inputs and provide mostly osseous details, this technique can help to illustrate the surrounding soft tissue structure and provide a realistic surgical simulation. The reconstructed 3D model was successfully used in simulating complex procedures in the virtual environment, including the transoral approach, bone drillings, and clivus resection.

  19. Posterior compartment defect repair in vaginal surgery: update on surgical techniques.

    PubMed

    Ginger, Van Anh T; Kobashi, Kathleen C

    2007-09-01

    Posterior colporrhaphy has been the most common surgical technique for the repair of posterior compartment defects. Traditional posterior colporrhaphy involves plication of the levator ani, which may result in dyspareunia related to narrowing of the introitus. Current posterior compartment repairs either plicate the midline fascia or repair the specific site of fascial weakness. Despite insubstantial data, the use of grafts to reinforce posterior repairs has gained popularity. Grafts such as allografts, xenografts, and synthetic meshes have been used to reinforce the posterior wall. Complications include infection and erosion, as well as recurrence of prolapse. Minimally invasive techniques have been developed to recreate the apical support of the vaginal vault and repair the posterior prolapse. Properly conducted randomized prospective trials are needed to adequately assess these new approaches.

  20. Laparoscopic Free Omental Flap for Craniofacial Reconstruction: A Video Article Demonstrating Operative Technique and Surgical Applications.

    PubMed

    McIntyre, Benjamin C; Lobb, David; Navarro, Fernando; Nottingham, James

    2017-03-01

    The omental flap is a well described pedicled flap for surgical reconstruction of multiple body locations. As a laparoscopically harvested free flap, the omentum offers a minimally invasive solution to many reconstructive problems including extremity and head and neck wounds. This video article highlights the operative technique involved in flap harvest and inset for a cranial defect. An illustrative case involving a 23-year-old female's traumatic scalp degloving injury that was resurfaced by free omental flap and split-thickness skin graft is presented. This patient had stable long-term wound coverage for a very severe injury. Through video media we demonstrate that the laparoscopically harvested free omental flap is a minimally invasive, 2-team operation that provides soft tissue coverage of severe, remote wounds. This video demonstrates a safe operative technique and nuances specific to laparoscopic harvest of this flap.

  1. Planned posterior assisted levitation in severe subluxated cataract: surgical technique and clinical results.

    PubMed

    Lifshitz, Tova; Levy, Jaime; Kratz, Assaf; Belfair, Nadav; Tsumi, Erez

    2012-01-01

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

  2. Ureteroscopy for management of stone disease: an up to date on surgical technique and disposable devices.

    PubMed

    Torricelli, Fabio C; Marchini, Giovanni S; Pedro, Renato N; Monga, Manoj

    2016-12-01

    The surgical management of urinary stone disease developed substantially over the past decades and advanced minimally invasive techniques have been successfully introduced into clinical practice. Retrograde ureteroscopy and ureterorrenoscopy have become the first-line option for treatment of ureteral and renal stones worldwide with high success rates allied with a low morbidity profile. In this review, we will discuss some key points in ureteroscopy for stone disease, such as the access to upper urinary tract, including balloon and catheter dilation; how to choose and use some disposable devices (hydrophilic versus PTFE guide wires, ureteral catheters, and laser fiber setting); and lastly present and compare different techniques for kidney or ureteral stone treatment (dusting versus basketing).

  3. A comparison of two anesthesia methods for the surgical removal of maxillary third molars: PSA nerve block technique vs. local infiltration technique

    PubMed Central

    2014-01-01

    Objectives: The purpose of this study was to compare the effect of PSA block injection with infiltration technique regarding local anesthesia for surgical extraction of upper third molar. Material and Methods: A prospective, intra individual, single-blind randomized controlled trial was designed to study the severity of pain during injection and after surgical extraction of the bilaterally and symmetrically similar upper third molar in a total of 53 patients, in addition to evaluating the need to repeat the injection and requirement of post operative anti-inflammatory tablets. Result: Although the average pain score for all studied times in PSA side was lower than the average pain score in infiltration technique, repeated statistical measures demonstrated that no significant pain reduction occurred in the two techniques. Conclusion: The both tested methods have the same statistic equivalence for the surgical extraction of maxillary third molars. Key words:Surgical extraction, maxillary third molars, PSA block, infiltration. PMID:24596629

  4. 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

  5. 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

  6. Adopting epidemic model to optimize medication and surgical intervention of excess weight

    NASA Astrophysics Data System (ADS)

    Sun, Ruoyan

    2017-01-01

    We combined an epidemic model with an objective function to minimize the weighted sum of people with excess weight and the cost of a medication and surgical intervention in the population. The epidemic model is consisted of ordinary differential equations to describe three subpopulation groups based on weight. We introduced an intervention using medication and surgery to deal with excess weight. An objective function is constructed taking into consideration the cost of the intervention as well as the weight distribution of the population. Using empirical data, we show that fixed participation rate reduces the size of obese population but increases the size for overweight. An optimal participation rate exists and decreases with respect to time. Both theoretical analysis and empirical example confirm the existence of an optimal participation rate, u*. Under u*, the weighted sum of overweight (S) and obese (O) population as well as the cost of the program is minimized. This article highlights the existence of an optimal participation rate that minimizes the number of people with excess weight and the cost of the intervention. The time-varying optimal participation rate could contribute to designing future public health interventions of excess weight.

  7. 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.

  8. 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.

  9. 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.

  10. To Determine the Method of Scheduling Surgery to Optimize Utilization of Surgical Resources at Landstuhl Army Regional Medical Center

    DTIC Science & Technology

    1984-05-01

    DETERMINE THE METHOD VF SCHEDULING SURGERY TO OPTIMIZE UTILIZATION OF SURGICAL RESOURCES AT LANDSTUHL ARMY REGIONAL MEDICAL CENTER 12. PERSONAL AUTHOR...GROUP Health Care, Surgery Scheduling 19, ABSTRACT (Continue on reverse if necessary and identify by block number) This study was conducted to determine...the optimum method of scheduling surgery to make maximum use of the surgical facilities at Landstuhl Army Regional Medical Center. Current scheduling

  11. Technical note: A new surgical technique for ovariohysterectomy during early pregnancy in beef heifers.

    PubMed

    McLean, K J; Dahlen, C R; Borowicz, P P; Reynolds, L P; Crosswhite, M R; Neville, B W; Walden, S D; Caton, J S

    2016-12-01

    We hypothesized that a standing flank ovariohysterectomy procedure could be developed in beef heifers that would provide high quality tissues for addressing critical questions during early pregnancy, while concomitantly keeping livestock stewardship a high priority. To test the hypothesis, we: 1) developed a standing flank ovariohysterectomy procedure for use in beef heifers, and 2) implemented this procedure in a cohort of heifers up to d 50 of pregnancy for tissue collections, documentation of post-surgical recovery, and assessment of feedlot finishing performance. Ovariectomy and cesarean section protocols are well established in research and veterinary medicine and were used as starting points for procedural development. Crossbred Angus heifers ( = 46; ∼ 15 mo of age; BW = 362.3 ± 34.7 kg) were used to develop this new surgical tissue collection technique. Heifers were subjected to the 5-d CO-Synch + CIDR estrous synchronization protocol so ovariohysterectomy occurred at d 16, 22, 28, 34, 40, and 50 of gestation. Key aspects of the standing flank ovariohysterectomy technique included 1) use of local anesthetic for a standing flank incision, 2) locate the uterine and ovarian arteries via blind palpation and ligate them through the broad ligament via an improved clinch knot, 3) cut the ovaries and uterus free from the broad ligament, 4) ligate the cervix and uterine branch of the vaginal artery, and 5) cut through the cervix and remove the reproductive tract. Surgical times, from skin incision to placement of the last suture, were influenced ( = 0.04) by stage of gestation. In pregnant heifers, time decreased from d 22 (120.0 ± 12.0 min) of gestation to d 40 (79.5 ± 12.0 min) of gestation; then increased at d 50 (90.5 ± 14.7 min) of gestation. Using this procedure, we obtained uterine, placental, and embryo/fetal tissues that had experienced limited hypoxia, little or no trauma, and thus were excellent quality for scientific study. All heifers recovered

  12. One stage hip arthroscopy and periacetabular osteotomy: surgical technique and initial results

    PubMed Central

    Zanotti, Gerardo; Comba, Fernando; Genovesi, Eduardo; Buttaro, Martin; Piccaluga, Francisco

    2017-01-01

    Aim: We purposed to describe the surgical technique and preliminary outcomes of combined arthroscopic and periacetabular osteotomy (PAO) for the treatment of non-arthritic hip dysplasia. Methods: Between May and August 2015, 4 patients (3 female, 1 male) with an average age of 29 years old (range; 22-33) had undergone one-stage hip arthroscopy and periacetabular osteotomy. Primary symptom was pain associated with instability. Upon radiographic examination, mean lateral center-edge angle of Wiberg was 12° (range; 7°-18°). Intra-articular findings were computed and primary outomes were as follows: radiographic angular correction; time to healing after pelvis osteotomy and functional results according to Merle D’Aubigné Score. Results: Minimum follow-up was 6 months whereas maximum was 9 months. Mean surgical time was 98 minutes for hip arthroscopy and 132 minutes for the osteotomy. In all cases, a lesion of the antero-superior labrum and the chondro-labral junction was found and repaired. After correction, overall postoperative center-edge angle was 29° (range; 25°-35°). Bone healing was certified in all cases at 6 months postoperatively. Overall Merle D’Aubigné Score was 17/18 points. Conclusion: Combined treatment of non-arthritic hip dysplasia with hip arthroscopy and PAO obtained good clinical and radiological outcomes. Former arthroscopy enables the diagnosis of cartilage lesions and intra-articular pathology as well as it aids in proceeding or not to an open correction.

  13. 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.

  14. Surgical treatment of complex proximal humeral fractures with a technique of nail and osteosuture: "NOS".

    PubMed

    Garret, J; Houdré, H; Cievet-Bonfils, M; Godenèche, Arnaud; Duparc, Fabrice; Roussignol, Xavier

    2017-03-14

    Open reduction and internal fixation of complex proximal humeral fracture represents a surgical challenge. The main objective of this procedure is to anatomically reduce the tuberosities. We propose a standardized and reproducible technique that we apply to all complex displaced 3- and 4-part fractures of patients under 50 years. We use an antero-lateral trans-deltoid approach; the humeral head and the tuberosities are reduced under fluoroscopic control. The tuberosities are stabilized with an inter-tuberosity osteosuture, and we then introduce a thin and straight intra-medullary nail (Telegraph IV FH Orthopedics) at the hinge point of the humeral head. The osteosynthesis of the tuberosities is completed by 3- or 4-self-stable divergent screws in the nail. A dynamic distal locking stabilizes the humeral shaft in rotation and facilitates consolidation thanks to micro movements. The removal of the nail with an arthroscopic shoulder arthrolysis in case of stiffness is possible secondarily.

  15. 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

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

    PubMed Central

    Nyame, Yaw A.; Babbar, Paurush; Aboumohamed, Ahmed A.; Mori, Ryan L.; Flechner, Stuart M.; Modlin, Charles S.

    2017-01-01

    Renal transplantation has profound improvements in mortality, morbidity, and overall quality of life compared to renal replacement therapy. This report aims to illustrate the use of ex-vivo partial nephrectomy in a patient with a renal angiomyolipoma prior to living donor transplantation. The surgical outcomes of the donor nephrectomy and recipient transplantation are reported with 2 years of follow-up. Both the donor and recipient are healthy and without any significant comorbidities. In conclusion, urologic techniques such as partial nephrectomy can be used to expand the living donor pool in carefully selected and well informed transplant recipients. Our experience demonstrated a safe and positive outcome for both the recipient and donor, and is consistent with other reported outcomes in the literature. PMID:28216945

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

    PubMed

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

    2010-07-01

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

  18. A surgical technique for bilateral cochleotomy in the Long-Evans rat.

    PubMed

    Swearengen, J R; Kittell, C L; Davis, J A; Raslear, T G; Beblo, D A; Colleton, C A

    1993-01-01

    A bilateral cochleotomized surgical rat model, needed for a study involving microwave effects, was developed, standardized, and assessed for reproducibility. After a review of the literature concerning attempts and approaches with various species, a technique involving an approach through the external auditory canal was chosen and modified. Using a stereomicroscope, a cutaneous incision in the intertragic notch was made and extended medially along the ventral aspect of the external auditory canal to the depth of the external auditory meatus. The tympanic membrane was ruptured and the malleus removed with splinter forceps, allowing visualization of the cochlea. The lateral wall of the cochlea was penetrated with a 0.024-in. wire gauge drill bit and endolymph was suctioned from the cochlea. A 5-mm piece of 3-O silk suture, inserted into the cochlear opening, maintained patency. Appraisal of the reliability and standardization of the procedure was performed utilizing startleometry. Histology assessed completeness of the procedure and any evidence of cochlear infection.

  19. [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.

  20. 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

  1. 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

  2. Patients' perceptions of recovery after surgical exposure of impacted maxillary teeth treated with an open-eruption surgical-orthodontic technique.

    PubMed

    Chaushu, S; Becker, A; Zeltser, R; Vasker, N; Chaushu, G

    2004-12-01

    This study assessed patient perceptions of immediate post-operative recovery after the surgical exposure of impacted maxillary teeth with an open-eruption technique. Thirty patients (24 females and six males) underwent surgical exposure of 39 impacted maxillary teeth using this technique. After surgery the patients were contacted by telephone daily for 7 days, to complete a health-related quality of life (HRQOL) questionnaire, which assessed their perception of recovery in four main areas: pain, oral function, general activity, and other symptoms. Severe pain was reported by 30 per cent of the patients in the first post-operative day (POD 1), which declined to 6.7 per cent by POD 6. Consumption of analgesics declined gradually over the post-operative days (POD 1: 80 per cent, POD 7: 20 per cent). Difficulty in eating required 5 days to reach minimal levels; enjoying everyday food, 2.5 days; school attendance, limitations in daily routine, swallowing, and speech, 2 days each; swelling, bad taste/smell, 1.5 days each; within 1 day all other measures attained minimal levels. The need for bone removal during the exposure resulted in delayed recovery with regard to the ability to eat. In general, females reported delayed recovery for pain. The present data may serve as basic guidelines against which future studies which assess post-operative management of patients after surgical exposure of impacted teeth by an open-eruption technique may be compared.

  3. 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.

  4. [Abdominal artery aneurysm and associated surgical abdominal diseases: towards optimal timing].

    PubMed

    Stilo, Francesco; Mirenda, Francesco; Mandolfino, Tommaso; La Spada, Michele; D'Alfonso, Mario; Carmignani, Amedeo; De Caridi, Giovanni; Benedetto, Filippo; Spinelli, Francesco

    2003-01-01

    The purpose of this study was to assess which modalities offered the best timing in the treatment of abdominal aortic aneurysms associated with other abdominal surgical diseases. From January 1984 to December 2002, 372 patients underwent surgery for abdominal aortic aneurysms, 350 men (94%) and 22 women (6%), mean age 72 years. Of these 10% were operated on urgently. The traditional open technique was used in 307 patients, and the endovascular method in the remaining 65 cases. In 40 patients (11%) we observed other associated abdominal diseases which were treated during the same operation in 34 cases (85%). We had three deaths in the 34 cases treated in the same operation (9%). In the remaining cases no perioperative mortality was registered. There were no cases of prosthesis infection. The mean hospital stay was 9 days. Simultaneous treatment appears, on the one hand, to carry an increased operative risk and increased mortality and, on the other, to present the advantage of having to perform only one surgical procedure. The advent of the endovascular method allows us to postpone the treatment of the associated disease without increasing the technical difficulty of the second operation.

  5. 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

  6. Surgical fixation of sternal fractures: preoperative planning and a safe surgical technique using locked titanium plates and depth limited drilling.

    PubMed

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

    2015-01-05

    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.

  7. 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.

  8. Retroperitoneal Laparoscopy in Dogs: Access Technique, Working Space, and Surgical Anatomy

    PubMed Central

    Jeong, Junemoe; Ko, Jonghyeok; Lim, Hyunjoo; Kweon, Oh‐Kyeong

    2016-01-01

    Objective To develop and describe a laparoscopic retroperitoneal access technique, investigate working space establishment, and describe the surgical anatomy in the retroperitoneal space as an initial step for clinical application of retroperitoneal laparoscopy in dogs. Study Design Cadaveric and experimental study. Animals Cadaveric (n=8) and healthy (n=6) adult dogs. Methods The retroperitoneal access technique was developed in 3 cadavers based on the human technique and transperitoneal observation. Its application and working space establishment with carbon dioxide (CO2) insufflation alone was evaluated in 5 cadavers by observing with a transperitoneal telescope and in 6 live dogs by repeated computed tomography (CT) scans at pressure of 0, 5, 10, and 15 mmHg. Recordings of retroperitoneoscopy as well as working space volume and linear dimensions measured on CT images were analyzed. Results Retroperitoneal access and working space establishment with CO2 insufflation alone were successfully performed in all 6 live dogs. The only complication observed was in 1 dog that developed subclinical pneumomediastinum. As pressure increased, working space was established from the ipsilateral to the contralateral side, and peritoneal tearing eventually developed. Working space volume increased significantly from 5 mmHg and linear dimensions increased significantly from 0 to 10 mmHg. With pneumo‐retroperitoneum above 5 mmHg, retroperitoneal organs, including kidneys and adrenal glands, were easily visualized. Conclusion The retroperitoneal access technique and working space establishment with CO2 insufflation starting with 5 mmHg and increasing to 10 mmHg provided adequate working space and visualization of retroperitoneal organs, which may allow direct access for retroperitoneal laparoscopy in dogs. PMID:27731512

  9. Different surgical techniques and L-carnitine supplementation in an experimental varicocele model.

    PubMed

    Akdemir, S; Gurocak, S; Konac, E; Ure, I; Onen, H I; Gonul, I I; Sozen, S; Menevse, A

    2014-10-01

    We aimed to investigate the impact of various varicocelectomy techniques and/or L-carnitine as an adjunct treatment, following the emergence of oxidative stress, on the expression levels of SCF/c-kit signalling pathways in spermatogenesis. Forty-two rats were divided into seven groups: group 1 (G1) control; group 2 (G2) sham; group 3 (G3) varicocele; group 4 (G4) varicocele + varicocelectomy with testicular nonartery sparing; group 5 (G5) same as G4 but with artery sparing; group 6 (G6) same as G4 but with L-carnitine and group 7 (G7) same as G5 with L-carnitine. mRNA expression levels of SCF and c-kit were measured quantitatively using real-time polymerase chain reaction. CASP-3 activity at protein level was determined, and histological evaluation was performed. mRNA expression level of SCF increased in G6 as compared to control group (3.52-folds change; P = 0.035), whereas mRNA expression level of c-kit gene remained the same. We found that in the left testis of G6 group, mRNA expression level of SCF increased 2.2-folds in comparison with the right testis (P < 0.05). There were no statistically significant differences in the CASP-3 protein expression levels between the control and other groups. When Cosentino Score analyses of immunostaining were conducted, we observed no significant differences among groups. Spermatogenic failure could be primarily due to a sertoli cell dysfunction. Although surgical treatment has been the best option for management of varicocele, auxiliary agents like L-carnitine may be considered as supportive treatment regimes in addition to conventional surgical treatments.

  10. 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.

  11. Evaluation of a minimally invasive surgical fixation technique for young children with the Concerto Pin cochlear implant system.

    PubMed

    Schnabl, Johannes; Wolf-Magele, Astrid; Pok, Stefan Marcel; Url, Christoph; Zorowka, Patrick; Sprinzl, Georg

    2015-08-01

    In 2011, Med-El (Innsbruck, Austria) introduced a new cochlear implant system, designed to require a minimally invasive surgical technique and allow greater positional flexibility for its fixation on the skull. The Concerto Pin implant system is a good option for patients with thinner bone, such as children and elderly. The aim of this study was to investigate the implant’s stability in children using our minimally invasive surgical technique. This was a prospective, longitudinal study with a single-subject, repeated-examination design. Six children, implanted with a Concerto Pin using our minimally invasive surgical technique between October 2011 and September 2012, were assessed 1, 3 and 6 months after surgery. In each case, the implant remained in a stable position and no adverse events or problems with healing were observed at any time during the investigation. The minimally invasive technique and the method of implant fixation that bypass drilling a deep implant bed constitute a good option for patients with thinner bone, such as children. This clinical study shows the safety and stability of the Concerto Pin implant system using a minimally invasive surgical technique.

  12. Controversial issues of optimal surgical timing and patient selection in the treatment planning of otosclerosis.

    PubMed

    Shiao, An-Suey; Kuo, Chin-Lung; Cheng, Hsiu-Lien; Wang, Mao-Che; Chu, Chia-Huei

    2014-05-01

    The aim of this study was to analyze the impact of clinical factors on the outcomes of otosclerosis surgery and support patients' access to evidence-based information in pre-operative counseling to optimize their choices. A total of 109 ears in 93 patients undergoing stapes surgery in a tertiary referral center were included. Variables with a potential impact on hearing outcomes were recorded, with an emphasis on factors that were readily available pre-operatively. Hearing success was defined as a post-operative air-bone gap ≤10 dB. Logistic regression analysis was used to determine the factors independently contributing to the prediction of hearing success. The mean follow-up period was 18.0 months. Univariate and multivariate analyses indicated that none of the pre-operative factors (piston type, age, sex, affected side, tinnitus, vertigo, and pre-operative hearing thresholds) affected hearing success significantly (all p > 0.05). In conclusion, self-crimping Nitinol piston provides comparable hearing outcomes with conventional manual-crimping prostheses. However, Nitinol piston offers a technical simplification of a surgical procedure and an easier surgical choice for patients. In addition, age is not a detriment to hearing gain and instead might result in better use of hearing aids in older adults, thus facilitating social hearing recovery. Finally, hearing success does not depend on the extent of pre-operative hearing loss. Hence, patients with poor cochlear function should not be considered poor candidates for surgery. The predictive model has established recommendations for otologists for better case selection, and factors that are readily available pre-operatively may inform patients more explicitly about expected post-operative audiometric results.

  13. Optimal Timing of Surgical Revascularization for Myocardial Infarction and Left Ventricular Dysfunction

    PubMed Central

    Wang, Rong; Cheng, Nan; Xiao, Cang-Song; Wu, Yang; Sai, Xiao-Yong; Gong, Zhi-Yun; Wang, Yao; Gao, Chang-Qing

    2017-01-01

    Background: The optimal timing of surgical revascularization for patients presenting with ST-segment elevation myocardial infarction (STEMI) and impaired left ventricular function is not well established. This study aimed to examine the timing of surgical revascularization after STEMI in patients with ischemic heart disease and left ventricular dysfunction (LVD) by comparing early and late results. Methods: From January 2003 to December 2013, there were 2276 patients undergoing isolated coronary artery bypass grafting (CABG) in our institution. Two hundred and sixty-four (223 male, 41 females) patients with a history of STEMI and LVD were divided into early revascularization (ER, <3 weeks), mid-term revascularization (MR, 3 weeks to 3 months), and late revascularization (LR, >3 months) groups according to the time interval from STEMI to CABG. Mortality and complication rates were compared among the groups by Fisher's exact test. Cox regression analyses were performed to examine the effect of the time interval of surgery on long-term survival. Results: No significant differences in 30-day mortality, long-term survival, freedom from all-cause death, and rehospitalization for heart failure existed among the groups (P > 0.05). More patients in the ER group (12.90%) had low cardiac output syndrome than those in the MR (2.89%) and LR (3.05%) groups (P = 0.035). The mean follow-up times were 46.72 ± 30.65, 48.70 ± 32.74, and 43.75 ± 32.43 months, respectively (P = 0.716). Cox regression analyses showed a severe preoperative condition (odds ratio = 7.13, 95% confidence interval 2.05–24.74, P = 0.002) rather than the time interval of CABG (P > 0.05) after myocardial infarction was a risk factor of long-term survival. Conclusions: Surgical revascularization for patients with STEMI and LVD can be performed at different times after STEMI with comparable operative mortality and long-term survival. However, ER (<3 weeks) has a higher incidence of postoperative low cardiac

  14. Transposition of Great Arteries with Intramural Coronary Artery: Experience with a Modified Surgical Technique

    PubMed Central

    Mishra, Amit; Jain, Anil; Hinduja, Manish; Wadhawa, Vivek; Patel, Ramesh; Vaidhya, Nikunj; Rodricks, Dayesh; Patel, Hardik

    2016-01-01

    Objective: Transposition of the great arteries is a common congenital heart disease. Arterial switch is the gold standard operation for this complex heart disease. Arterial switch operation in the presence of intramural coronary artery is surgically the most demanding even for the most experienced hands. We are presenting our experience with a modified technique for intramural coronary arteries in arterial switch operation. Methods: This prospective study involves 450 patients undergoing arterial switch operation at our institute from April 2006 to December 2013 (7.6 years). Eighteen patients underwent arterial switch operation with intramural coronary artery. The coronary patterns and technique used are detailed in the text. Results: The overall mortality found in the subgroup of 18 patients having intramural coronary artery was 16% (n=3). Our first patient had an accidental injury to the left coronary artery and died in the operating room. A seven-day old newborn died from intractable ventricular arrhythmia fifteen hours after surgery. Another patient who had multiple ventricular septal defects with type B arch interruption died from residual apical ventricular septal defect and sepsis on the eleventh postoperative day. The remainder of the patients are doing well, showing a median follow-up duration of 1235.34±815.26 days (range 369 - 2730). Conclusion: Transposition of the great arteries with intramural coronary artery is demanding in a subset of patients undergoing arterial switch operation. We believe our technique of coronary button dissection in the presence of intramural coronary arteries using coronary shunt is simple and can be a good addition to the surgeons' armamentarium. PMID:27074270

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

    PubMed Central

    Capriglione, Luiz Guilherme Achcar; Barchiki, Fabiane; Ottoboni, Gabriel Sales; Miyague, Nelson Itiro; Suss, Paula Hansen; Rebelatto, Carmen Lúcia Kuniyoshi; Pimpão, Cláudia Turra; Senegaglia, Alexandra Cristina; Brofman, Paulo Roberto

    2014-01-01

    Objective To perform a comparative assessment of two surgical techniques that are used creating an acute myocardial infarc by occluding the left anterior descending coronary artery in order to generate rats with a left ventricular ejection fraction of less than 40%. Methods The study was completely randomized and comprised 89 halothane-anaesthetised rats, which were divided into three groups. The control group (SHAM) comprised fourteen rats, whose left anterior descending coronary artery was not occluded. Group 1 (G1): comprised by 35 endotracheally intubated and mechanically ventilated rats, whose left anterior descending coronary artery was occluded. Group 2 (G2): comprised 40 rats being manually ventilated using a nasal respirator whose left anterior descending coronary artery was occluded. Other differences between the two techniques include the method of performing the thoracotomy and removing the pericardium in order to expose the heart, and the use of different methods and suture types for closing the thorax. Seven days after surgery, the cardiac function of all surviving rats was determined by echocardiography. Results No rats SHAM group had progressed to death or had left ventricular ejection fraction less than 40%. Nine of the 16 surviving G1 rats (56.3%) and six of the 20 surviving G2 rats (30%) had a left ventricular ejection fraction of less than 40%. Conclusion The results indicate a tendency of the technique used in G1 to be better than in G2. This improvement is probably due to the greater duration of the open thorax, which reduces the pressure over time from the surgeon, allowing occlusion of left anterior descending coronary artery with higher accuracy. PMID:25714202

  16. Degenerative mitral valve disease-contemporary surgical approaches and repair techniques.

    PubMed

    Koprivanac, Marijan; Kelava, Marta; Alansari, Shehab; Javadikasgari, Hoda; Tappuni, Bassman; Mick, Stephanie; Marc, Gillinov A; Suri, Rakesh; Mihaljevic, Tomislav

    2017-01-01

    Given the increasing age of the US population and the accompanying rise in cardiovascular disease, we expect to see an increasing number of patients affected by degenerative mitral valve disease in a more complex patient population. Therefore, increasing the overall rate of mitral valve repair will become even more important than it is today, and the capability to provide a universally and uniformly accepted quality of repair will have important medical, economic, and societal implications. This article will describe preoperative and intraoperative considerations and the currently practiced mitral valve repair approaches and techniques. The aim of the article is to present our contemporary approach to mitral valve repair in the hope that it can be adopted at other institutions that may have low repair rates. Adoption of simple and reproducible mitral valve repair techniques is of paramount importance if we as a profession are to accomplish overall higher rates of mitral valve repair with optimal outcomes.

  17. Degenerative mitral valve disease-contemporary surgical approaches and repair techniques

    PubMed Central

    Kelava, Marta; Alansari, Shehab; Javadikasgari, Hoda; Tappuni, Bassman; Mick, Stephanie; Marc, Gillinov A.; Suri, Rakesh; Mihaljevic, Tomislav

    2017-01-01

    Given the increasing age of the US population and the accompanying rise in cardiovascular disease, we expect to see an increasing number of patients affected by degenerative mitral valve disease in a more complex patient population. Therefore, increasing the overall rate of mitral valve repair will become even more important than it is today, and the capability to provide a universally and uniformly accepted quality of repair will have important medical, economic, and societal implications. This article will describe preoperative and intraoperative considerations and the currently practiced mitral valve repair approaches and techniques. The aim of the article is to present our contemporary approach to mitral valve repair in the hope that it can be adopted at other institutions that may have low repair rates. Adoption of simple and reproducible mitral valve repair techniques is of paramount importance if we as a profession are to accomplish overall higher rates of mitral valve repair with optimal outcomes. PMID:28203540

  18. Indication, surgical technique and results of endoscopic fascial release in plantar fasciitis (E FRPF).

    PubMed

    Jerosch, Jörg; Schunck, Jochem; Liebsch, Dietrich; Filler, Tim

    2004-09-01

    The purpose of the present study is to present the surgical technique for, and review our indications and results after, endoscopic fascial release in patients with plantar fasciitis. In five thiel-embalmed human specimens, a biportal technique for endoscopic release of the plantar fascia was established. The aim was here to evaluate the relation between the plantar fascia and the heel spur and to perform a release that would not exceed 50-70% of the diameter of the calcaneoplantar fascia. The endoscopic technique was performed within the last 5 years in ten male and seven female patients. All patients with the clinical entity of plantar fasciitis underwent conservative treatment for at least 6 months. The average age at surgery was 35 years (24-56 years). In the first five patients, surgery was performed under c-arm control. In all patients the operation could be finished endoscopically. The endoscopic portals healed without complications. The time for surgery during the learning curve ranged between 21 and 74 min (average 41 min) and was still longer compared to the open technique. The clinical follow-up ranged between 4 and 48 months (average 18.5 months). Out of 17 patients, 13 improved clinically, and they would choose the treatment option again. In the Ogilvie-Harris score, seven patients showed good and six excellent results. In two patients, the initial results were not satisfactory, because of a bony stress reaction of the calcaneus. This complication was treated by 6 weeks of partial weight bearing, without any further problems. Two other patients developed secondary pain in the lateral column. In spite of the minimal invasive approach it seems to be important to be careful in increasing the weight bearing in early rehabilitation. The technique of the endoscopic plantar fascia release (E FRPF) can be performed in a standardised and reproducible procedure. The follow-up examination showed good midterm results, but a loss of stability of the plantar arch

  19. New simple technique for hepatic parenchymal resection using a Cavitron Ultrasonic Surgical Aspirator and bipolar cautery equipped with a channel for water dripping.

    PubMed

    Yamamoto, Y; Ikai, I; Kume, M; Sakai, Y; Yamauchi, A; Shinohara, H; Morimoto, T; Shimahara, Y; Yamamoto, M; Yamaoka, Y

    1999-10-01

    We have developed a new technique to resect hepatic parenchyma without inflow occlusion by using the Cavitron Ultrasonic Surgical Aspirator (CUSA) and bipolar cautery with a saline irrigation system. The significance of this method in hepatectomy was analyzed in comparison with historical control of hepatectomy using Pringle's maneuver. An ordinary bipolar cautery was remodeled with an infusion line to bring saline droplets down the inner surface of one arm of the tweezers through an opening about 1.5 cm proximal to its tip. The optimal flow rate of saline was approximately one drop per second. The power of bipolar cautery was adjusted to 50 watts. When the tweezer blades were approximated to 1 or 2 mm, saline droplets were directed to the tip of tweezers and could be immediately evaporated. After sonicating parenchymal cells, the tissue of small branches of Glisson's tree or small tributaries of the hepatic vein were coagulated by bipolar cautery. The coagulated cords were then easily cut by scissors. The impact of this technique on ordinary liver resections was evaluated by analyzing the postoperative clinical course in relation to the hepatic functional reserve necessary for major hepatectomy, duration of hepatectomy, and intraoperative blood loss. Hepatic resection without vascular occlusion using this technique could decrease the morbidity in patients who have less hepatic functional reserve. It could also decrease intraoperative blood loss. This new technique effectively decreased the surgical load of the remnant liver during parenchymal resection by avoiding ischemic stress. Consequently it extends the safety limits of major hepatectomy.

  20. Vagus nerve stimulation: Surgical technique of implantation and revision and related morbidity.

    PubMed

    Giordano, Flavio; Zicca, Anna; Barba, Carmen; Guerrini, Renzo; Genitori, Lorenzo

    2017-04-01

    Indications for vagus nerve stimulation (VNS) therapy include focal, multifocal epilepsy, drop attacks (tonic/atonic seizures), Lennox-Gastaut syndrome, tuberous sclerosis complex (TSC)-related multifocal epilepsy, and unsuccessful resective surgery. Surgical outcome is about 50-60% for seizures control, and may also improve mood, cognition, and memory. On this basis, VNS has also been proposed for the treatment of major depression and Alzheimer's' disease. The vagus nerve stimulator must be implanted with blunt technique on the left side to avoid cardiac side effects through the classic approach for anterior cervical discectomy. The actual device is composed of a wire with three helical contacts (two active contacts, one anchoring) and a one-pin battery. VNS is usually started 2 weeks after implantation with recommended settings of stimulation (1.0-2.0 mA; 500 μs pulse width; 20-30 Hz; 30 s ON, 5 min OFF). The complications of VNS therapy are early (related to surgery) and late (related to the device and to stimulation of the vagus nerve). Early complications include the following: intraoperative bradycardia and asystole during lead impedance testing, peritracheal hematoma, infections (3-8%), and vagus nerve injury followed by hoarseness, dyspnea, and dysphagia because of left vocal cord paralysis. Delayed morbidity due to the device includes late infections or problems in wound healing; other more rare events are due to late injury of the nerve. Late complications due to nerve stimulation include delayed arrhythmias, laryngopharyngeal dysfunction (hoarseness, dyspnea, and coughing), obstructive sleep apnea, stimulation of phrenic nerve, tonsillar pain mimicking glossopharyngeal neuralgia, and vocal cord damage during prolonged endotracheal intubation. The laryngopharyngeal dysfunction occurs in about 66% of patients and is usually transitory and due to the stimulation of the inferior (recurrent) laryngeal nerve. A true late paralysis of the left vocal cord

  1. Influence of implant shape, surface morphology, surgical technique and bone quality on the primary stability of dental implants.

    PubMed

    Elias, Carlos Nelson; Rocha, Felipe Assis; Nascimento, Ana Lucia; Coelho, Paulo Guilherme

    2012-12-01

    The primary stability of dental implants has been investigated before, but a study of the influence of implant shape, size and surface morphology (machined, acid etched or anodized), surgical technique (press-fit or undersized) and substrate (natural or simulated bone) on the primary stability of dental implants has not been reported. The present work intends to fill this gap. In this work, six different dental implants were inserted into and removed from synthetic and natural bone while measuring the torque. A total of 255 dental implants with three shapes, four sizes and three surface topographies were inserted into pig rib, PTFE and polyurethane. The implant sites were prepared using straight and tapered drills. The primary stability was estimated from the maximum insertion torque. Comparisons between samples were based on the maximum insertion torque (MIT), the maximum removal torque (MRT) and the torque ratio (TR=MRT/MIT). The insertion torque into pig ribs showed larger dispersion. All parameters (shape, size and surface morphology of the implant, surgical technique and substrate type) were found to have a significant influence on primary stability. The insertion of a tapered implant requires a higher torque than the insertion of a straight implant. Surface treatments improve the primary stability. The influence of the surgical technique is smaller than that of implant size and shape. The highest insertion torque was that of anodized tapered implants inserted into undersized sites. Finally, the primary stability of dental implants is highly dependent on implant design, surgical technique and substrate type.

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

    PubMed

    Hernández Carrazco, Mayra Elena; Rodríguez Torres, Alejandra; Ortiz Pineda, Omar; Rodríguez Torres, Juan; Casas Patiño, Donovan

    2014-07-04

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

  3. “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

  4. Repair or Reconstruction in Acute Posterolateral Instability of the Knee: Decision Making and Surgical Technique Introduction.

    PubMed

    Stannard, James P; Stannard, James T; Cook, James L

    2015-12-01

    Complex knee injury surgeons must frequently decide whether to repair or reconstruct an acute posterolateral corner (PLC) injury. If repair is not feasible or fails, reconstruction is often necessary. Several studies have found that reconstruction has better outcomes and lower failure rates. Careful studies of the anatomy of the corner have led to the development of "two-tailed" reconstruction techniques which are becoming widely used in the field. Repair should not be completely disregarded as there are times when it is necessary, especially when no donor allograft tissue is readily available or when aggressive postoperative rehabilitation will not be performed. Optimally, if the patient has high quality tissue available for repair, it is best to combine reconstruction with repair. The authors have developed a new PLC reconstruction technique which applies the functional anatomy that has been increasingly defined. We detail these methods here, which include the use of cortical button suspensory fixation and interference screw fixation of allografts in sockets. This allows for individual and sequential intraoperative tensioning of the grafts to obtain optimal knee stability and motion.

  5. Soft tissue reconstruction for type IV-D duplicated thumb: a new surgical technique.

    PubMed

    Tien, Yin-Chun; Chih, Tsai-Tung; Wang, Tai-Lung; Fu, Yin-Chih; Chen, Jian-Chih

    2007-06-01

    Type IV-D duplicated thumb has the most complex anomalies and difficulties for treatment among polydatyly. Double osteotomy is usually recommended to gain the best cosmetic and functional outcome. However, 4 cases of type IV-D duplicated thumb were treated only by soft tissue procedure in this study. At operation, a conjoined A2 pulley was routinely identified, and the flexor pollicis longus (FPL) was found bifurcated distal to the conjoined pulley in every of these cases. Instead of double osteotomy, a soft tissue procedure that included centralization of FPL and A2 pulley reconstruction was pursued to correct these special anomalies. The overall clinical results were evaluated by a modification of the Tada scoring system based on the range of motion, joint stability, alignment of the remaining thumb, and subjective opinion regarding the reconstructed thumb after an average follow-up of 3.3 years (range, 2.5-4.7 years). According to the scoring system, the results were rated as good in 3 cases and fair in 1 case. From the results, the A2 pulley reconstruction and FPL centralization could prove to be an effective method for the treatment of type IV-D duplicated thumb and could efficiently avoid the residual angular deformities. Therefore, we recommend this soft tissue procedure as an alternative surgical technique to the double-osteotomy procedure for treating a type IV-D duplicated thumb in a very young child, whose bone is still not mature enough for holding the fixing pins.

  6. Blood Conservation Strategies and Liver Transplantation Transfusion-Free Techniques Derived from Jehovah's Witness Surgical Cohorts.

    PubMed

    Sheth, Mansi; Kulkarni, Sujit; Dhanireddy, Kiran; Perez, Alexander; Selby, Rick

    2015-01-01

    Red blood cell and component transfusions are a frequent and widely accepted accompaniment of surgical procedures. Although the risk of specific disease transmission via allogeneic blood transfusions (ABT) is very low, the occurrence of transfusion related immune modulation (TRIM) still remains a ubiquitous concern. Recent studies have shown that ABT are linked to increased morbidity and mortality across various specialties, with negative outcomes directly correlated to number of transfusions. Blood conservation methods are therefore necessary to reduce ABT. Acute normo-volemic hemodilution (ANH) along with pre-operative blood augmentation and intraoperative cell salvage are blood conservation techniques utilized in tertiary and even quaternary (transplantation) surgery in Jehovah's Witnesses with excellent outcomes. The many hematologic complications such as anemia, thrombocytopenia and coagulopathies that occur with liver transplantation present a significant barrier when trying to avoid ABT. Despite this, living donor liver transplantation (LDLT) has been successfully performed in a transfusion-free environment, providing valuable insight into the possibilities of limiting ABT and its associated risks in all patients.

  7. Parasagittal meningiomas: Our surgical experience and the reconstruction technique of the superior sagittal sinus

    PubMed Central

    Ricci, Alessandro; Di Vitantonio, Hambra; De Paulis, Danilo; Del Maestro, Mattia; Gallieni, Massimo; Dechcordi, Soheila Raysi; Marzi, Sara; Galzio, Renato Juan

    2017-01-01

    Background: The radical resection of parasagittal meningiomas without complications and recurrences is the goal of the neurosurgeon. Nowadays, different managements are proposed. This study describes our surgical technique during the lesional excision and the reconstruction of the superior sagittal sinus (SSS). Methods: The total removal (Simpson I and II) of parasagittal meningiomas (WHO grade I and II) was obtained in 75 patients from September 2000 to January 2010. The indocyanine green videoangiography was used before the dural opening and, when necessary, to identify and preserve the cortical veins. The surgery of the SSS was performed in accordance with Sindou's classification, and its reconstruction was achieved through the use of a patch of galea capitis. Results: We had no cases of recurrence and thrombotic occlusion of the SSS in 5 years after the reconstruction. No complications were observed in 65 patients, and no cases of mortality were reported. Neurological focal deficits were observed in 5 patients. A brain swelling and a venous infarction were observed in 1 patient. Only one case of thrombotic occlusion was observed. A cerebrospinal fluid leak was observed in 2 patients, and a systemic complication was found in 1 patient. Conclusion: Several factors contribute to the success of the parasagittal meningioma surgery. We consider the preservation of the cortical veins to be important, and, when possible, we recommend the reconstruction of the anterior third of the SSS. Our experience has led us to believe that until now surgery is a winning choice if practiced by expert hands. PMID:28217380

  8. Gene therapy during cardiac surgery: role of surgical technique to minimize collateral organ gene expression

    PubMed Central

    Katz, Michael G.; Swain, JaBaris D.; Fargnoli, Anthony S.; Bridges, Charles R.

    2013-01-01

    Effective gene therapy for heart failure has not yet been achieved clinically. The aim of this study is to quantitatively assess the cardiac isolation efficiency of the molecular cardiac surgery with recirculating delivery (MCARD™) and to evaluate its efficacy as a means to limit collateral organ gene expression. 1014 genome copies (GC) of recombinant adeno-associated viral vector 6 encoding green fluorescent protein under control of the cytomegalovirus promoter was delivered to the nine arrested sheep hearts. Blood samples were assessed using real-time quantitative polymerase chain reaction (RT QPCR). Collateral organ gene expression was assessed at four-weeks using immunohistochemical staining. The blood vector GC concentration in the cardiac circuit during complete isolation trended from 9.59±0.73 to 9.05±0.65 (log GC/cm3), and no GC were detectable in the systemic circuit (P<0.001). The washing procedure performed prior to relinquishing the cardiac circuit decreased the systemic blood vector GC concentration >800-fold (P<0.001), consistent with >99% isolation efficiency. Conversely, incomplete isolation resulted in equalization of vector GC concentration in the circuits, leading to robust collateral organ gene expression. MCARD™ is an efficient, clinically translatable myocardial delivery platform for cardiac specific gene therapy. The cardiac surgical techniques utilized are critically important to limit collateral organ gene expression. PMID:20861057

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

    PubMed

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

    2009-10-01

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

  10. The endoscopic endonasal approach to the Meckel's cave tumors: surgical technique and indications.

    PubMed

    Jouanneau, Emmanuel; Simon, Emile; Jacquesson, Timothée; Sindou, Marc; Tringali, Stéphane; Messerer, Mahmoud; Berhouma, Moncef

    2014-12-01

    Many benign and malignant tumors as well as other inflammatory or vascular diseases may be located in the areas of Meckel's cave or the cavernous sinus. Except for typical features such as for meningiomas, imaging may not by itself be sufficient to choose the best therapeutic option. Thus, even though modern therapy (chemotherapy, radiotherapy, or radiosurgery) dramatically reduces the field of surgery in this challenging location, there is still some place for surgical biopsy or tumor removal in selected cases. Until recently, the microscopic subtemporal extradural approach with or without orbitozygomatic removal was classically used to approach Meckel's cave but with a non-negligible morbidity. Percutaneous biopsy using the Hartel technique has been developed for biopsy of such tumors but may fail in the case of firm tumors, and additionally it is not appropriate for anterior parasellar tumors. With the development of endoscopy, the endonasal route now represents an interesting alternative approach to Meckel's cave as well as the cavernous sinus. Through our experience, we describe the modus operandi and discuss what should be the appropriate indication of the use of the endonasal endoscopic approach for Meckel's cave disease in the armamentarium of the skull base surgeon.

  11. Cardiac gene therapy: optimization of gene delivery techniques in vivo.

    PubMed

    Katz, Michael G; Swain, JaBaris D; White, Jennifer D; Low, David; Stedman, Hansell; Bridges, Charles R

    2010-04-01

    Vector-mediated cardiac gene therapy holds tremendous promise as a translatable platform technology for treating many cardiovascular diseases. The ideal technique is one that is efficient and practical, allowing for global cardiac gene expression, while minimizing collateral expression in other organs. Here we survey the available in vivo vector-mediated cardiac gene delivery methods--including transcutaneous, intravascular, intramuscular, and cardiopulmonary bypass techniques--with consideration of the relative merits and deficiencies of each. Review of available techniques suggests that an optimal method for vector-mediated gene delivery to the large animal myocardium would ideally employ retrograde and/or anterograde transcoronary gene delivery,extended vector residence time in the coronary circulation, an increased myocardial transcapillary gradient using physical methods, increased endothelial permeability with pharmacological agents, minimal collateral gene expression by isolation of the cardiac circulation from the systemic, and have low immunogenicity.

  12. 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

  13. 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

  14. [Arthrodesis of the elbow joint. Indications, surgical technique and clinical results].

    PubMed

    Moghaddam-Alvandi, A; Dremel, E; Güven, F; Heppert, V; Wagner, C; Studier-Fischer, S; Grützner, P A; Biglari, B

    2010-04-01

    Arthrodesis of the elbow joint (EA) is a rare salvage procedure which is disliked by both surgeons and patients. The aim of this study was to analyze the indications, the operation techniques and the outcome of EA in patients treated at our clinic. Between January 1997 and December 2005 a total of 20 patients with a mean age of 55 years (range 27-85 years) were treated with EA at our clinic. In 18 patients a compression plate was used as surgical technique. In 18 out of the 20 patients the operation was performed post-traumatically after infection, bone and tissue defects and painful loss of motion. Of these patients, 16 could be followed up for an average time of 66 months. The outcome was evaluated based on the degree of pain, range of motion, radiographic findings and grip strength measured with the Jamar dynamometer. All patients had a solid and fused EA, the average angle was 89 degrees (range 80-110 degrees) and the grip strength was reduced by 27% compared to the unaffected side. The patients achieved 56 points in the Morrey score, 38.29 points in the DASH (disabilities of the arm, shoulder and hand) score and 80 points in the Constant-Murley score. The indication of EA depends on several factors, therefore it is essential to take the patients' functional requirements into consideration and the best arthrodesis angle should be validated pre-operatively. In these cases the patients can regain good grip strength and a high level of stability within defined functional limitations.

  15. The CORONIS Trial. International study of caesarean section surgical techniques: a randomised fractional, factorial trial

    PubMed Central

    2007-01-01

    Background Caesarean section is one of the most commonly performed operations on women throughout the world. Rates have increased in recent years – about 20–25% in many developed countries. Rates in other parts of the world vary widely. A variety of surgical techniques for all elements of the caesarean section operation are in use. Many have not yet been rigorously evaluated in randomised controlled trials, and it is not known whether any are associated with better outcomes for women and babies. Because huge numbers of women undergo caesarean section, even small differences in post-operative morbidity rates between techniques could translate into improved health for substantial numbers of women, and significant cost savings. Design CORONIS is a multicentre, fractional, factorial randomised controlled trial and will be conducted in centres in Argentina, Ghana, India, Kenya, Pakistan and Sudan. Women are eligible if they are undergoing their first or second caesarean section through a transverse abdominal incision. Five comparisons will be carried out in one trial, using a 2 × 2 × 2 × 2 × 2 fractional factorial design. This design has rarely been used, but is appropriate for the evaluation of several procedures which will be used together in clinical practice. The interventions are: • Blunt versus sharp abdominal entry • Exteriorisation of the uterus for repair versus intra-abdominal repair • Single versus double layer closure of the uterus • Closure versus non-closure of the peritoneum (pelvic and parietal) • Chromic catgut versus Polyglactin-910 for uterine repair The primary outcome is death or maternal infectious morbidity (one or more of the following: antibiotic use for maternal febrile morbidity during postnatal hospital stay, antibiotic use for endometritis, wound infection or peritonitis) or further operative procedures; or blood transfusion. The sample size required is 15,000 women in total; at least 7,586 women in each comparison

  16. Arthroscopic grafting of scaphoid nonunion - surgical technique and preliminary findings from 23 cases.

    PubMed

    Cognet, J-M; Louis, P; Martinache, X; Schernberg, F

    2017-02-01

    We report our experience with the arthroscopic treatment of 23 cases of scaphoid nonunion. We explain the surgical technique and describe the different steps needed to achieve bone union. We report our initial clinical and radiological results. This was a prospective non-randomized study. Inclusion criteria were a scaphoid nonunion without radiocarpal arthritis, without any time limit and without any selection as to nonunion location. Before the operation, patients underwent an X-Ray and CT scan or MRI. Schernberg's classification was used to evaluate the location of the nonunion. Internal fixation was performed with a screw or K-wires. Bone grafts were taken from the dorsal side of the distal radius using a T-Lok™ bone marrow biopsy needle (Argon Medical Devices, Plano, TX, USA). A CT scan was performed 3 months after the operation to determine whether union was achieved. Pain, strength and range of motion were evaluated before and after the operation. The patients' smoking habits were also documented. The average follow-up was 17.3 months (4-41). There were 20 men and 3 women with an average age of 26 years (17-63). The average duration of nonunion before the operation was 17 months (6-60). Based on Schernberg's classification, there was one type I, 12 type II and 10 type III nonunions. Wrist strength increased from 32 to 41kg. Union was obtained in all patients after an average of 4 months (3-12). Numerous treatments have been described for treating scaphoid nonunion: Matti-Russe, Fisk-Fernadez bone graft, vascularized bone graft, bone substitutes, etc. The success rate varies depending on the technique and study design. We have described an arthroscopic technique for treating scaphoid nonunion with very promising preliminary results. Arthroscopic debridement is needed to ensure good quality bone at the graft site, while preserving extrinsic vascularization. Traction is used during the operation to restore the scaphoid height, once debridement has been

  17. Energy optimization in chiller plants: A novel formulation and solution using a hybrid optimization technique

    NASA Astrophysics Data System (ADS)

    Aravelli, Aparna; Rao, Singiresu S.

    2013-10-01

    The central chilled water plant is one of the major power-consuming units of a building. Even small reductions in power consumption could achieve significant energy conservation. Hence, optimization of a chiller plant is necessary for energy savings without compromising the comfort level of the end user. The present work deals with identifying the system parameters and developing a novel formulation for a chiller plant and its optimization using a hybrid optimization technique. The optimization model formulation is based on finding an optimal mix of equipment and operating parameters in the chiller plant for minimum electrical power consumption. It takes into account the performance characteristics of the chillers, cooling towers and pumps, and optimizes the energy consumed based on the required loads and the ambient atmospheric conditions. Sequential quadratic programming combined with the modified branch and bound method was used to develop the hybrid optimization algorithm. A case study is presented for a typical chiller plant. The results indicate that the present optimization method could be a potential method of making energy savings.

  18. 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

  19. Total hip replacement in an ipsilateral above-the-knee amputation: surgical technique, rehabilitation, and review of the literature.

    PubMed

    Malagelada, Francesc; Coll Rivas, Moisès; Jiménez Obach, Albert; Auleda, Jaume; Guirao, Lluis; Pleguezuelos, Eulogio

    2013-03-01

    In this article, we present a case report of a 62-year-old patient who previously underwent an above-the-knee amputation for vascular disease and we performed a total hip replacement on him because of hip osteoarthritis. As the only postoperative complication, the patient developed a methicillin-resistant Staphylococcus aureus surgical site infection, which was successfully treated. The surgical technique and the postoperative rehabilitation program are described in detail in an attempt to detect and face the challenges that patients with major lower limb amputations may present. The literature is reviewed and all known cases of hip replacements in amputees are presented.

  20. 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.

  1. 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.

  2. Parapharyngeal metastases from thyroid cancer: surgical management of two cases with minimally-invasive video-assisted technique.

    PubMed

    Giordano, L; Pilolli, F; Toma, S; Bussi, M

    2015-10-01

    Metastases to parapharyngeal or retropharyngeal lymph nodes are rare in well-differentiated thyroid cancers. A review of English literature found only 112 cases reported in the last two decades, with an incidence of parapharyngeal lymph nodes metastases ranging from 0.43 to 2.5%. Surgical resection is the most effective treatment for patients with parapharyngeal lymph node metastasis from thyroid carcinoma. We describe two cases of thyroid cancer parapharyngeal lymph node metastases that were surgically removed using a traditional transcervical approach, with the help of a minimally-invasive video-assisted technique. A video-assisted minimally-invasive transcervical approach is a new technique for excision of sizable benign tumours and selected malignant tumours. The endoscopic technique allows clear identification of critical surgical landmarks that guide the dissection through the correct cleavage plane in a nearly bloodless surgical field, thus decreasing the rate of complications. In both patients postoperative follow-up showed no sequelae and recurrence after 20 and 15 months from surgery.

  3. Far lateral microdiscectomy: a minimally-invasive surgical technique for the treatment of far lateral lumbar disc herniation

    PubMed Central

    Phan, Kevin; Dunn, Alexander E.; Rao, Prashanth J.

    2016-01-01

    Lumbar disc herniation arises when the annulus fibrosus of the vertebral disc fails, thus allowing displacement of the nucleus pulposus and other tissue. The term far lateral is used variably in the literature and usually refers to an extraforaminal displacement in the peridiscal zone peripheral to the sagittal plane of the most lateral part of the pedicle at the same level. Non-surgical treatments of far lateral disc herniation include physical therapy, anti-inflammatory medication, and corticosteroid injections. Where these conservative measures fail, surgical intervention may be required. Several surgical techniques for the treatment of far lateral herniations have been investigated, including total or medial facetectomy, laminectomy, hemilaminectomy, approaches through the pars interarticularis, and lateral approaches between the transverse processes via the intertransverse muscle and ligament. We present our far lateral microdiscectomy technique which involves accessing the nerve root lateral to the foramen through a small paramedian incision and use of an operating microscope. Far lateral microdiscectomy offers the prospect of better long-term results than other surgical techniques because of less extensive muscle dissection and preservation of the integrity of the facet joint. PMID:27683697

  4. 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.

  5. 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.

  6. Imaging technique optimization of tungsten anode FFDM system

    NASA Astrophysics Data System (ADS)

    Chen, Biao; Smith, Andrew P.; Jing, Zhenxue; Ingal, Elena

    2009-02-01

    Single Mo target, Mo / Rh, or Mo / W bi-track targets with corresponding Mo and Rh filters have provided optimal target / filter combinations for traditional screen / film systems. In the advent of full-field digital mammography, similar target / filter combinations were adopted directly for digital imaging systems with direct and indirect conversion based detectors. To reduce the average glandular dose while maintaining the clinical image quality of FFDMs, alternative target / filter combinations have been investigated extensively to take advantages of the digital detectors with high dynamic range, high detection dose efficiency, and low noise level. This paper reports the development of a digital FFDM system that is equipped with single tungsten target and rhodium and silver filters. A mathematical model was constructed to quantitatively simulate x-ray spectra, breast compositions, contrast objects, x-ray scatter distribution, grid performance, and characteristics of a-Se flat panel detector. Computer simulations were performed to select kV/filter for different breast thickness and breast compositions through maximizing the contrast object detection dose efficiency. A set of phantom experiments were employed to optimize the x-ray techniques within the constraints of exposure time and required dose levels. A 50-micrometer rhodium filter was applied for thin and average breasts and a 50-micrometer silver filter for thicker breasts. To meet our design requirements and EUREF protocol specifications, we finely adjusted x-ray techniques for 0.45, 0.75, 1.0, 1.35 mGy dose modes with regards to ACR phantom scoring and PMMA phantom SNR/CNR performance, respectively. The optimal x-ray techniques significantly reduce average glandular dose while maintaining imaging performance.

  7. 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

  8. Pulley Reconstruction As Part of the Surgical Treatment for de Quervain Disease: Surgical Technique with Medium-Term Results.

    PubMed

    van der Wijk, Jacobien; Goubau, Jean F; Mermuys, Koen; van Hoonacker, Petrus; Vanmierlo, Bert; Kerckhove, Diederick; Berghs, Bart

    2015-08-01

    Background Simple decompression of the first extensor compartment is commonly used for treating de Quervain disease, with the possible complication of subluxation of the tendons of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) over the radial styloid. To prevent this painful subluxation of the tendons, several methods of reconstructing the pulley have been proposed. Questions/Purposes The purpose of our study was to evaluate a new technique for reconstructing the first extensor compartment following a release for de Quervain disease. Patients and Methods A retrospective study (mean length 40.4 months) was performed in 45 patients. The outcome assessment involved two different questionnaires and ultrasound evaluation of any tendon subluxation. Results None of the patients required reoperation for tendon instability or incomplete decompression of the first extensor compartment. Two patients experienced clicking around the radial styloid after surgery. This was not related to the amount of volar migration of the tendons. Conclusions We believe the reconstruction proposed here is an effective method of preventing painful subluxation of the APL and EPB following a release of the first extensor compartment.

  9. Pulley Reconstruction As Part of the Surgical Treatment for de Quervain Disease: Surgical Technique with Medium-Term Results

    PubMed Central

    van der Wijk, Jacobien; Goubau, Jean F.; Mermuys, Koen; van Hoonacker, Petrus; Vanmierlo, Bert; Kerckhove, Diederick; Berghs, Bart

    2015-01-01

    Background Simple decompression of the first extensor compartment is commonly used for treating de Quervain disease, with the possible complication of subluxation of the tendons of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) over the radial styloid. To prevent this painful subluxation of the tendons, several methods of reconstructing the pulley have been proposed. Questions/Purposes The purpose of our study was to evaluate a new technique for reconstructing the first extensor compartment following a release for de Quervain disease. Patients and Methods A retrospective study (mean length 40.4 months) was performed in 45 patients. The outcome assessment involved two different questionnaires and ultrasound evaluation of any tendon subluxation. Results None of the patients required reoperation for tendon instability or incomplete decompression of the first extensor compartment. Two patients experienced clicking around the radial styloid after surgery. This was not related to the amount of volar migration of the tendons. Conclusions We believe the reconstruction proposed here is an effective method of preventing painful subluxation of the APL and EPB following a release of the first extensor compartment. PMID:26261747

  10. 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

  11. Design of high speed proprotors using multiobjective optimization techniques

    NASA Technical Reports Server (NTRS)

    Mccarthy, Thomas R.; Chattopadhyay, Aditi

    1993-01-01

    A multidisciplinary optimization procedure is developed for the design of high speed proprotors. The objectives are to simultaneously maximize the propulsive efficiency in high speed cruise without sacrificing the rotor figure of merit in hover. Since the problem involves multiple design objectives, multiobjective function formulation techniques are used. A derailed two-celled isotropic box beam is used to model the load carrying member within the rotor blade. Constraints are imposed on rotor blade aeroelastic stability in cruise, the first natural frequency in hover and total blade weight. Both aerodynamic and structural design variables are used. The results obtained using both techniques are compared to the reference rotor and show significant aerodynamic performance improvements without sacrificing dynamic and aeroelastic stability requirements.

  12. A novel noise optimization technique for inductively degenerated CMOS LNA

    NASA Astrophysics Data System (ADS)

    Zhiqing, Geng; Haiyong, Wang; Nanjian, Wu

    2009-10-01

    This paper proposes a novel noise optimization technique. The technique gives analytical formulae for the noise performance of inductively degenerated CMOS low noise amplifier (LNA) circuits with an ideal gate inductor for a fixed bias voltage and nonideal gate inductor for a fixed power dissipation, respectively, by mathematical analysis and reasonable approximation methods. LNA circuits with required noise figure can be designed effectively and rapidly just by using hand calculations of the proposed formulae. We design a 1.8 GHz LNA in a TSMC 0.25 μm CMOS process. The measured results show a noise figure of 1.6 dB with a forward gain of 14.4 dB at a power consumption of 5 mW, demonstrating that the designed LNA circuits can achieve low noise figure levels at low power dissipation.

  13. Minimax Techniques For Optimizing Non-Linear Image Algebra Transforms

    NASA Astrophysics Data System (ADS)

    Davidson, Jennifer L.

    1989-08-01

    It has been well established that the Air Force Armament Technical Laboratory (AFATL) image algebra is capable of expressing all linear transformations [7]. The embedding of the linear algebra in the image algebra makes this possible. In this paper we show a relation of the image algebra to another algebraic system called the minimax algebra. This system is used extensively in economics and operations research, but until now has not been investigated for applications to image processing. The relationship is exploited to develop new optimization methods for a class of non-linear image processing transforms. In particular, a general decomposition technique for templates in this non-linear domain is presented. Template decomposition techniques are an important tool in mapping algorithms efficiently to both sequential and massively parallel architectures.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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.

  20. 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

  1. A New Apparatus and Surgical Technique for the Dual Perfusion of Human Tumor Xenografts in Situ in Nude Rats

    PubMed Central

    Dauchy, Robert T; Dauchy, Erin M; Mao, Lulu; Belancio, Victoria P; Hill, Steven M; Blask, David E

    2012-01-01

    We present a new perfusion system and surgical technique for simultaneous perfusion of 2 tissue-isolated human cancer xenografts in nude rats by using donor blood that preserves a continuous flow. Adult, athymic nude rats (Hsd:RH-Foxn1rnu) were implanted with HeLa human cervical or HT29 colon adenocarcinomas and grown as tissue-isolated xenografts. When tumors reached an estimated weight of 5 to 6 g, rats were prepared for perfusion with donor blood and arteriovenous measurements. The surgical procedure required approximately 20 min to complete for each tumor, and tumors were perfused for a period of 150 min. Results showed that tumor venous blood flow, glucose uptake, lactic acid release, O2 uptake and CO2 production, uptake of total fatty acid and linoleic acid and conversion to the mitogen 13-HODE, cAMP levels, and activation of several marker kinases were all well within the normal physiologic, metabolic, and signaling parameters characteristic of individually perfused xenografts. This new perfusion system and technique reduced procedure time by more than 50%. These findings demonstrate that 2 human tumors can be perfused simultaneously in situ or ex vivo by using either rodent or human blood and suggest that the system may also be adapted for use in the dual perfusion of other organs. Advantages of this dual perfusion technique include decreased anesthesia time, decreased surgical manipulation, and increased efficiency, thereby potentially reducing the numbers of laboratory animals required for scientific investigations. PMID:22546915

  2. Surgical correction of cleft lip and palate.

    PubMed

    Jayaram, Rahul; Huppa, Christoph

    2012-01-01

    Surgical cleft repair aims to restore function of the oro-nasal sphincter and oro-nasal soft tissues and re-establish the complex relationship between perioral and perinasal muscle rings without compromising subsequent mid-facial growth and development. Here we review the surgical anatomy of this region, optimal timing for surgical repair and current thinking on the use of surgical adjuncts. In addition, an overview of current surgical techniques available for the repair of cleft lip, cleft palate and velopharyngeal insufficiency is presented. Finally, we briefly discuss nasal revision surgery and the use of osteotomy, including distraction osteogenesis in the cleft patient.

  3. Review of optimization techniques of polygeneration systems for building applications

    NASA Astrophysics Data System (ADS)

    Y, Rong A.; Y, Su; R, Lahdelma

    2016-08-01

    Polygeneration means simultaneous production of two or more energy products in a single integrated process. Polygeneration is an energy-efficient technology and plays an important role in transition into future low-carbon energy systems. It can find wide applications in utilities, different types of industrial sectors and building sectors. This paper mainly focus on polygeneration applications in building sectors. The scales of polygeneration systems in building sectors range from the micro-level for a single home building to the large- level for residential districts. Also the development of polygeneration microgrid is related to building applications. The paper aims at giving a comprehensive review for optimization techniques for designing, synthesizing and operating different types of polygeneration systems for building applications.

  4. 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.

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

    PubMed

    Mei, Yuyang

    2016-09-23

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

  6. 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.

  7. 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.

  8. Application of microsatellite PCR techniques in the identification of mixed up tissue specimens in surgical pathology.

    PubMed

    Gras, E; Matias-Guiu, X; Catasus, L; Arguelles, R; Cardona, D; Prat, J

    2000-03-01

    A fragment of tumour was erroneously mixed up with an endometrial biopsy. Micro-satellite polymerase chain reaction (PCR) clearly demonstrated the extraneous nature of the fragment. Micro-satellite PCR may be useful for the identification of mis-labelled or mismatched tissue fragments in surgical pathology specimens.

  9. An Alternative Surgical Technique for Repair of Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery

    PubMed Central

    Kim, Young-su; Lee, Mina; Cho, Yang Hyun; Yang, Ji-Hyuk; Jun, Tae-Gook

    2014-01-01

    Background For the surgical management of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA), there have been various techniques that reduce the tension and kinking of the coronary artery during reimplantation to the aorta. The aim of this study is to describe the results of our modified technique of coronary reimplantation for the treatment of ALCAPA. Methods Between October 2003 and February 2011, seven patients underwent coronary reimplantation with the modified technique (tubing formation with the sinus wall of the pulmonary artery and trapdoor formation at the site of implantation in the aorta). The median follow-up duration was 52 months (range, 4 to 72 months). Clinical outcomes and serial echocardiographic data were reviewed. Results There was no mortality. One patient had a small amount of cerebral hemorrhage postoperatively and improved without any sequelae. Another patient had left diaphragm palsy and underwent diaphragm plication. Follow-up echocardiogram showed that all patients had normal ventricular function without chamber enlargement. Conclusion Our modified technique (tubing formation with the sinus wall of the pulmonary artery and trapdoor formation at the site of implantation in the aorta) demonstrated successful clinical outcomes. We conclude that this surgical technique can be a potential alternative for the treatment of ALCAPA. PMID:25207218

  10. 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

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

    PubMed

    Westerdahl, E

    2015-06-01

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

  12. Surgical treatment of adult moyamoya disease with combined STA-MCA bypass and EDAS: demonstration of technique in video presentation.

    PubMed

    Li, Yiping; Cikla, Ulas; Baggott, Christopher; Yilmaz, Tevfik; Chao, Clifford; Baskaya, Mustafa K

    2015-01-01

    The natural history of Moyamoya disease (MD) is variable. Moyamoya disease in children mostly presents with progressive ischemic complications and in adulthood it tends to present with hemorrhage. Surgical strategies depend on augmenting cerebral blood flow to the anterior cerebral circulation. Revascularization is the mainstay treatment for MD. We introduce a 31 year old female with a history of MD and leftsided revascularization as a child, who presented with headache, confusion, and worsening left sided weakness. Cranial computed tomography (CT) showed a right sided putaminal hemorrhage. Cerebral angiogram with selective external runs revealed MD, hypoplastic parietal branch of the superficial temporal artery (STA) on the right side and previous revascularization on the left side. Thus, our decision was made to perform a bypass with the frontal branch of the STA to an M3-M4 segment of the middle cerebral artery and an encephaloduroarteriomyosynangiosis with the parietal branch of the STA. The patient's postoperative course was uneventful. Postoperative CT angiogram confirmed patency of bypass. This technique provides immediate revascularization and seems to provide risk reduction for ischemic and hemorrhagic stroke. We review the natural history and surgical treatment of MD along with a case presentation in which surgical technique is demonstrated in video.

  13. 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

  14. The importance of drug-induced sedation endoscopy (D.I.S.E.) techniques in surgical decision making: conventional versus target controlled infusion techniques-a prospective randomized controlled study and a retrospective surgical outcomes analysis.

    PubMed

    De Vito, Andrea; Agnoletti, Vanni; Zani, Gianluca; Corso, Ruggero Massimo; D'Agostino, Giovanni; Firinu, Elisabetta; Marchi, Chiara; Hsu, Ying-Shuo; Maitan, Stefano; Vicini, Claudio

    2017-02-17

    Drug-Induced Sedation Endoscopy (DISE) consists of the direct observation of the upper airways during sedative-induced sleep, allowing the identification of the sites of pharyngeal collapse, which is the main pathological event in Obstructive Sleep Apnea (OSA). The Authors have compared Target Controlled Infusion (TCI) sedation endoscopy (TCI-DISE) technique to conventional DISE (CDISE), performed by a manual bolus injection of sedative agent, to recreate accurately and safely snoring and apnea patterns comparable to natural sleep. The authors conducted a prospective, randomized, long-term study and a retrospective analysis of surgical outcomes. The apnea-event observation and its correlation with pharyngeal collapse patterns is the primary endpoint; secondary endpoints are defined as stability and safety of sedation plan of DISE-TCI technique. From January 2009 to January 2011, OSA patients were included in the study and randomly allocated into two groups: the bolus injection conventional DISE group and the TCI-DISE group. Third endpoint is to compare the surgical outcomes enrolling OSA patients from January 2009 to June 2015. We recorded the complete apnea-event at oropharynx and hypopharynx levels in 15/50 pts in conventional DISE group (30%) and in 99/123 pts in TCI-DISE group (81%) (p < 0.0001). Four pts needed oxygen in conventional DISE group because a severe desaturation occurred during the first bolus of propofol (1 mg/kg) (p = 0.4872 ns). We recorded instability of the sedation plan in 13 patients of conventional DISE group (65%) and 1 patient of the TCI-DISE group (5%) (p = 0.0001). In 37 TCI-DISE group surgical patients we reported a significant reduction of postoperative AHI (from 42.7 ± 20.2 to 11.4 ± 10.3) in comparison with postoperative AHI in 15 C-DISE group surgical patients (from 41.3 ± 23.4 to 20.4 ± 15.5) (p = 0.05). Our results suggest the DISE-TCI technique as first choice in performing sleep

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

    PubMed

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

    2013-09-01

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

  16. An Inexpensive Modified Primary Closure Technique for Class IV (Dirty) Wounds Significantly Decreases Superficial and Deep Surgical Site Infection.

    PubMed

    Kim, Bradford J; Aloia, Thomas A

    2016-11-01

    Despite the creation of several programs to decrease the incidence of surgical site infection, it remains a common complication that has a significant impact on patient recovery and medical costs. The following is a description and brief outcome report of a modified primary closure technique used for dirty (Class IV) wounds. There were 14 consecutive patients who had a laparotomy with Class IV wounds treated by a single surgeon (TAA) from 2011 to 2015. All patients had a history of cancer and either showed signs suggestive for an acute abdomen and required an emergent exploratory laparotomy or were found to have purulent intraabdominal infection at the time of elective surgery. The operation and "modified primary closure" technique (subcutaneous wound wicks with stapled skin closure) were performed in every case. The modified primary closure technique was utilized in 14 patients with a Class IV wound. There were no 30-day mortalities or readmissions. Wound wicks were slowly advanced out over a 7-day period, and only one patient required subsequent wound packing of a single-wicked area. There were no superficial or deep surgical site infections, or wound dehiscence during the hospital course, or 30-day postoperative period. The modified primary closure technique is efficient and inexpensive and was effective in a series of 14 patients with wounds classified as dirty.

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

    PubMed

    Vijayan, S; Bentley, G; Briggs, Twr; Skinner, Ja; Carrington, Rwj; Pollock, R; Flanagan, Am

    2010-07-01

    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.

  18. 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

  19. Posttraumatic progressive cubitus varus deformity managed by lateral column shortening: A novel surgical technique.

    PubMed

    Srivastava, Amit; Jain, Anil-Kumar; Dhammi, Ish Kumar; Haq, Rehan-Ul

    2016-08-01

    The outward angulation of elbow with supinated forearm is cubitus varus deformity. This deformity is often seen as sequelae of malunited supracondylar fracture of humerus in paediatric age group of 5e8 years. The deformity is usually non-progressive, but in cases of physeal injury or congenital bony bar formation in the medial condyle of humerus, the deformity is progressive and can be grotesque in appearance. Various types of osteotomies are defined for standard non-progressive cubitus varus deformity, while multiple surgeries are required for progressive deformity until skeletal maturity. In this study we described a novel surgical approach and osteotomy of distal humerus in a 5 years old boy having grotesque progressive cubitus varus deformity, achieving good surgical outcome.

  20. Achilles tendon reattachment after surgical treatment of insertional tendinosis using the suture bridge technique: a case series.

    PubMed

    Witt, Bryan L; Hyer, Christopher F

    2012-01-01

    Achilles tendinopathy is a clinical diagnosis characterized as a triad of symptoms including pain, swelling, and impaired performance of the diseased tendon. Achilles tendinopathy is divided into Achilles tendonitis and tendinosis based on histopathological examination. Achilles tendinosis is viewed microscopically as disorganized collagen, abnormal neovascularization, necrosis, and mucoid degeneration. Insertional Achilles tendinosis is a degenerative process of the tendon at the junction of the tendon and calcaneus. This disease is initially treated conservatively with activity modification, custom orthotic devices, heel lifts, and immobilization. After 3 to 6 months of conservative therapy has failed to alleviate symptoms, surgical management is indicated. Surgical management of insertional Achilles tendinosis includes Achilles tendon debridement, calcaneal exostosis ostectomy, and retrocalcaneal bursa excision. In this case series, we present 4 patients who underwent surgical management of insertional Achilles tendinosis with complete tendon detachment. All patients underwent reattachment of the Achilles tendon with the suture bridge technique. The Arthrex SutureBridge(®) (Arthrex, Inc., Naples, FL) device uses a series of 4 suture anchors and FiberWire(®) (Arthrex Inc.) to reattach the Achilles tendon to its calcaneal insertion. This hourglass pattern of FiberWire(®) provides a greater area of tendon compression, consequently allowing greater stability and possible earlier return to weightbearing activities. The patients were followed up for approximately 2 years' duration. There were no intraoperative or postoperative complications. At final follow-up there was no evidence of Achilles tendon ruptures or device failures. All patients were able to return to their activities of daily living without the use of assistive devices. The patients' average visual analog pain scale was 1 (range 0 to 4), and their average foot functional index score was 3.41 (range 0

  1. 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.

  2. In vitro biomechanical evaluation of four surgical techniques for fusion of equine centrodistal and tarsometatarsal joints.

    PubMed

    Biedrzycki, Adam H; Grant, Barrie G; Nemke, Brett; Morello, Samantha L; Markel, Mark D

    2016-10-01

    OBJECTIVE To evaluate the biomechanical properties of 4 methods for fusion of the centrodistal and tarsometatarsal joints in horses and compare them among each other and with control tarsi. SAMPLE 24 sets of paired tarsi without substantial signs of osteoarthritis harvested from equine cadavers. PROCEDURES Test constructs (n = 6/type) were prepared from 1 tarsus from each pair to represent surgical drilling; 2 medially to laterally placed kerf-cut cylinders (MLKCs); a single large, dorsally applied kerf-cut cylinder (DKC); and a dorsomedially applied locking compression plate (DMLCP). Constructs and their contralateral control tarsi were evaluated in 4-point bending in the dorsoplantar, lateromedial, and mediolateral directions; internal and external rotation; and axial compression. Bending, torsional, and axial stiffness values were calculated. RESULTS Mean stiffness values were consistently lower for surgical drilling constructs than for contralateral control tarsi. Over all biomechanical testing, surgical drilling significantly reduced joint stability. The MLKC constructs had superior biomechanical properties to those of control tarsi for 4-point bending but inferior properties for external and internal rotation. The DMLCP and DKC constructs were superior to control tarsi in dorsoplantar, rotational, and axial compression directions only; DMLCP constructs had no superior stiffness in lateromedial or mediolateral directions. Only the DKC constructs had greater stiffness in the mediolateral direction than did control tarsi. Over all biomechanical testing, DMLCP and DKC constructs were superior to the other constructs. CONCLUSIONS AND CLINICAL RELEVANCE These biomechanical results suggested that a surgical drilling approach to joint fusion may reduce tarsal stability in horses without clinical osteoarthritis, compared with stability with no intervention, whereas the DMLCP and DKC approaches may significantly enhance stability.

  3. 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.

  4. 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.

  5. The surgical correction of mandibular prognathism using rigid internal fixation--a report of a new technique together with its long-term stability.

    PubMed Central

    Reitzik, M.

    1988-01-01

    A historical review of the literature for the surgical correction of mandibular prognathism is presented, together with a list of ideal conditions for the successful treatment of this condition. This is a report of a new surgical technique which satisfies the majority of these principles and demonstrates stability at the osteotomy site. PMID:3207331

  6. 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.

  7. Surgical treatment of excessive gingival display using lip repositioning technique and laser gingivectomy as an alternative to orthognathic surgery.

    PubMed

    Gabrić Pandurić, Dragana; Blašković, Marko; Brozović, Juraj; Sušić, Mato

    2014-02-01

    Excessive gingival display (EGD) is a condition in which an overexposure of the maxillary gingiva (>3 mm) is present during smiling. The proper diagnosis and determination of its etiology are essential for the selection of the right treatment modality. Different techniques have been used in cases of hyperactive upper lip: botulinum toxin injections, lip elongations with rhinoplasties, lip muscle detachments, myotomies, and lip repositions. This report presents a case of a young woman with an EGD larger than 10 mm during smiling caused by altered passive eruption, vertical maxillary excess, and a hyperactive upper lip that was treated with a modified lip repositioning technique and laser gingivectomy because she strongly refused orthognathic surgical treatment. A novel addition to the technique is proposed, a reversible trial accomplished just by applying sutures on the borders of the future split-thickness flap, marked using diode laser, before starting the flap incision.

  8. An Information-Centric Approach to Autonomous Trajectory Planning Utilizing Optimal Control Techniques

    DTIC Science & Technology

    2009-09-01

    INFORMATION-CENTRIC APPROACH TO AUTONOMOUS TRAJECTORY PLANNING UTILIZING OPTIMAL CONTROL TECHNIQUES by Michael A. Hurni September 2009...Dissertation 4. TITLE AND SUBTITLE: An Information-centric Approach to Autonomous Trajectory Planning Utilizing Optimal Control Techniques 6...then finding a time- optimal time scaling for the path subject to the actuator limits. The direct approach searches for the trajectory directly

  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. [The surgical tactic optimization in local accumulations of liquid in patients with severe acute pancreatitis].

    PubMed

    Sheĭko, V D; Oganezian, A H

    2013-12-01

    The results of examination and treatment of 56 patients, having local accumulations of liquid (IAL) in severe acute pancreatitis (SAP), were analyzed. Transcutaneous puncture-draining sanation was performed in 47 (83.9%) patients; 7 (12.5%)--were treated without surgical intervention; in 2 (3.6%)--open operative interventions were done. SIRS was revealed in 31 (55.4%) patients, the signs of the LAL infectioning in accordance to the ultrasonographic investigation data, computeric tomography (CT) without SIRS was observed in 2 (93.6%), the compression features--in 45 (80.4%). Application of surgical tactics proposed in accordance to the data of the ultrasonographic monitoring of LAL, the signs of compression and the SIRS presence with determination of contents and infectioning have had permitted to improve the treatment results in patients, suffering SAP.

  11. 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.

  12. Bariatric surgery for morbid obesity: pre-operative assessment, surgical techniques and post-operative monitoring.

    PubMed

    Breznikar, Brane; Dinevski, D

    2009-01-01

    This observational clinical analysis included 246 patients who underwent surgery for adjustable gastric banding (AGB), laparoscopic sleeve gastrectomy (LSG), or gastric bypass (GBP) between May 2005 and December 2008. The most frequent surgical procedure was for AGB (73.2% of patients). A thorough psychological evaluation of the patients was carried out, and pre- and post-operative psychological and dietary support was offered. A total of 111/120 (92.5%) AGB patients, 21/30 (70.0%) LSG patients and 8/36 (22.2%) GBP patients have been monitored for at least 1 year, and their mean weight losses (percentage excess weight loss) were 24.7 kg (52.4%), 46.0 kg (57.9%) and 40.5 kg (77.9%), respectively. The AGB procedure was associated with the fewest complications but is not appropriate for all patients. Good pre-operative psychological evaluation has been shown to be necessary for successful outcomes and, in the super-obese, we prefer to use LSG. Surgeons should learn the skills needed to perform laparoscopic Roux-en-Y GBP as it is likely to become the standard-of-care for the surgical treatment of obesity. The best outcomes following bariatric surgery are achieved with a multidisciplinary approach, including participation in a support group guided by a psychologist.

  13. [Optimization of anesthesiological maintenance of x-ray surgical interventions in children].

    PubMed

    Sterkhov, R V; Vinogradova, M S; Mizikov, V M

    2002-01-01

    Two procedures for intravenous anesthesia during X-ray surgical interventions were evaluated in 38 children aged 3 to 13 years. Initial anesthesia (with intramuscular midazole and ketamine), followed by the fractional use of the latter agents in Group 1 and propofol in Group 2, in order to maintain anesthesia. Blood pressure (BP) (noninvasively), heart rate (HR), SpO2, and respiratory rate (RR) were monitored. After the initial anesthesia, mean BP (BPmean) increased by 40 and 24% in Groups 1 and 2, respectively. So did HR by 23 and 31%, respectively. In Group these changes retained throughout the basic stage of intervention. In Group 2 on propofol infusion, BPmean and HR returned to normal values and remained at this level till the end of the intervention, SpO2 and RR did not differ from the baseline values in both groups. Thus, a combination of intravenous ketamine and intramuscular propofol provides steady-state values of BP and HR at the basic state of X-ray surgical intervention in children, which increases the reliability of studies and surgical safety in patients.

  14. Techniques for development of safety-related software for surgical robots.

    PubMed

    Varley, P

    1999-12-01

    Regulatory bodies require evidence that software controlling potentially hazardous devices is developed to good manufacturing practices. Effective techniques used in other industries assume long timescales and high staffing levels and can be unsuitable for use without adaptation in developing electronic healthcare devices. This paper discusses a set of techniques used in practice to develop software for a particular innovative medical product, an endoscopic camera manipulator. These techniques include identification of potential hazards and tracing their mitigating factors through the project lifecycle.

  15. 3D Computer graphics simulation to obtain optimal surgical exposure during microvascular decompression of the glossopharyngeal nerve.

    PubMed

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

    2013-10-01

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

  16. 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.

  17. 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

  18. Robotic Surgery in Women With Ovarian Cancer: Surgical Technique and Evidence of Clinical Outcomes.

    PubMed

    Minig, Lucas; Padilla Iserte, Pablo; Zorrero, Cristina; Zanagnolo, Vanna

    2016-01-01

    Robotic surgery is a new technology that has been progressively implemented to treat endometrial and cervical cancer. However, the use of robotic surgery for ovarian cancer is limited to a few series of cases and comparative studies with laparoscopy or laparotomy. The technical issues concerning robotic surgery, as well as clinical evidence, are described in this review. Robotic surgery in early stage, advanced stage, and relapsed ovarian cancer is discussed separately. In conclusion, evidence regarding the use of robotic-assisted surgical treatment for women with ovarian cancer is still scarce, but its use is progressively growing. Robotic-assisted staging in selected patients with early stage disease has an important role in referral institutions when well-trained gynecologists perform surgeries. However, minimally invasive surgery in patients with advanced stage or relapsed ovarian cancer requires further investigation, even in selected cases.

  19. 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.

  20. 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

  1. The influence of surgical technique on early posttransplant atrial fibrillation – comparison of biatrial, bicaval, and total orthotopic heart transplantation

    PubMed Central

    Rivinius, Rasmus; Helmschrott, Matthias; Ruhparwar, Arjang; Erbel, Christian; Gleissner, Christian A; Darche, Fabrice F; Thomas, Dierk; Bruckner, Tom; Katus, Hugo A; Doesch, Andreas O

    2017-01-01

    Purpose Early posttransplant atrial fibrillation (AF) has been associated with worse clinical outcomes after heart transplantation (HTX). The type of surgical technique may constitute a relevant risk factor for AF. Patients and methods This retrospective single-center study included 530 adult patients. Patients were stratified by surgical technique (biatrial, bicaval, or total orthotopic HTX) and early posttransplant heart rhythm (AF or sinus rhythm). Univariate and multivariate analyses were performed to evaluate risk factors for AF. Results A total of 161 patients received biatrial HTX (30.4%), 115 bicaval HTX (21.7%), and 254 total orthotopic HTX (47.9%). Sixty-one of 530 patients developed early posttransplant AF (11.5%). Patients with AF showed a statistically inferior 5-year survival compared to those with sinus rhythm (P<0.0001). Total orthotopic HTX had the lowest rate of AF (total orthotopic HTX [6.3%], bicaval HTX [14.8%], biatrial HTX [17.4%], P=0.0012). Multivariate analysis showed pretransplant valvular heart disease (P=0.0372), posttransplant enlarged left atrium (P=0.0066), posttransplant mitral regurgitation (P=0.0370), and non-total orthotopic HTX (P=0.0112) as risk factors for AF. Conclusion Early posttransplant AF was associated with increased mortality (P<0.0001). Total orthotopic HTX showed the lowest rate of AF compared to biatrial or bicaval HTX (P=0.0012). PMID:28331331

  2. Point-cloud-to-point-cloud technique on tool calibration for dental implant surgical path tracking

    NASA Astrophysics Data System (ADS)

    Lorsakul, Auranuch; Suthakorn, Jackrit; Sinthanayothin, Chanjira

    2008-03-01

    Dental implant is one of the most popular methods of tooth root replacement used in prosthetic dentistry. Computerize navigation system on a pre-surgical plan is offered to minimize potential risk of damage to critical anatomic structures of patients. Dental tool tip calibrating is basically an important procedure of intraoperative surgery to determine the relation between the hand-piece tool tip and hand-piece's markers. With the transferring coordinates from preoperative CT data to reality, this parameter is a part of components in typical registration problem. It is a part of navigation system which will be developed for further integration. A high accuracy is required, and this relation is arranged by point-cloud-to-point-cloud rigid transformations and singular value decomposition (SVD) for minimizing rigid registration errors. In earlier studies, commercial surgical navigation systems from, such as, BrainLAB and Materialize, have flexibility problem on tool tip calibration. Their systems either require a special tool tip calibration device or are unable to change the different tool. The proposed procedure is to use the pointing device or hand-piece to touch on the pivot and the transformation matrix. This matrix is calculated every time when it moves to the new position while the tool tip stays at the same point. The experiment acquired on the information of tracking device, image acquisition and image processing algorithms. The key success is that point-to-point-cloud requires only 3 post images of tool to be able to converge to the minimum errors 0.77%, and the obtained result is correct in using the tool holder to track the path simulation line displayed in graphic animation.

  3. Swine (Sus scrofa) as a Model of Postinfarction Mitral Regurgitation and Techniques to Accommodate Its Effects during Surgical Repair

    PubMed Central

    Sarin, Eric L; Shi, Weiwei; Duara, Rajnish; Melone, Todd A; Kalra, Kanika; Strong, Ashley; Girish, Apoorva; McIver, Bryant V; Thourani, Vinod H; Guyton, Robert A; Padala, Muralidhar

    2016-01-01

    Mitral regurgitation (MR) is a common heart-valve lesion after myocardial infarction in humans. Because it is considered a risk factor for accelerated heart failure and death, various surgical approaches and catheter-based devices to correct it are in development. Lack of a reproducible animal model of MR after myocardial infarction and reliable techniques to perform open-heart surgery in these diseased models led to the use of healthy animals to test new devices. Thus, most devices that are deemed safe in healthy animals have shown poor results in human efficacy studies, hampering progress in this area of research. Here we report our experience with a swine model of postinfarction MR, describe techniques to induce regurgitation and perform open-heart surgery in these diseased animals, and discuss our outcomes, complications, and solutions. PMID:27538860

  4. Swine (Sus scrofa) as a Model of Postinfarction Mitral Regurgitation and Techniques to Accommodate Its Effects during Surgical Repair.

    PubMed

    Sarin, Eric L; Shi, Weiwei; Duara, Rajnish; Melone, Todd A; Kalra, Kanika; Strong, Ashley; Girish, Apoorva; McIver, Bryant V; Thourani, Vinod H; Guyton, Robert A; Padala, Muralidhar

    2016-01-01

    Mitral regurgitation (MR) is a common heart-valve lesion after myocardial infarction in humans. Because it is considered a risk factor for accelerated heart failure and death, various surgical approaches and catheter-based devices to correct it are in development. Lack of a reproducible animal model of MR after myocardial infarction and reliable techniques to perform open-heart surgery in these diseased models led to the use of healthy animals to test new devices. Thus, most devices that are deemed safe in healthy animals have shown poor results in human efficacy studies, hampering progress in this area of research. Here we report our experience with a swine model of postinfarction MR, describe techniques to induce regurgitation and perform open-heart surgery in these diseased animals, and discuss our outcomes, complications, and solutions.

  5. Onboard Science Techniques to Optimize Science Data Retrieval from Small Spacecraft

    NASA Astrophysics Data System (ADS)

    Lightholder, J.; Thompson, D. R.; Huffman, W.; Boland, J.; Chien, S.; Castillo-Rogez, J.

    2016-10-01

    Software strategies for new onboard science techniques which optimize science return under the constrains of interplanetary small spacecraft. These include size, power, attitude control and communications bandwidth.

  6. Optimization and evolution in metabolic pathways: global optimization techniques in Generalized Mass Action models.

    PubMed

    Sorribas, Albert; Pozo, Carlos; Vilaprinyo, Ester; Guillén-Gosálbez, Gonzalo; Jiménez, Laureano; Alves, Rui

    2010-09-01

    Cells are natural factories that can adapt to changes in external conditions. Their adaptive responses to specific stress situations are a result of evolution. In theory, many alternative sets of coordinated changes in the activity of the enzymes of each pathway could allow for an appropriate adaptive readjustment of metabolism in response to stress. However, experimental and theoretical observations show that actual responses to specific changes follow fairly well defined patterns that suggest an evolutionary optimization of that response. Thus, it is important to identify functional effectiveness criteria that may explain why certain patterns of change in cellular components and activities during adaptive response have been preferably maintained over evolutionary time. Those functional effectiveness criteria define sets of physiological requirements that constrain the possible adaptive changes and lead to different operation principles that could explain the observed response. Understanding such operation principles can also facilitate biotechnological and metabolic engineering applications. Thus, developing methods that enable the analysis of cellular responses from the perspective of identifying operation principles may have strong theoretical and practical implications. In this paper we present one such method that was designed based on nonlinear global optimization techniques. Our methodology can be used with a special class of nonlinear kinetic models known as GMA models and it allows for a systematic characterization of the physiological requirements that may underlie the evolution of adaptive strategies.

  7. 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.

  8. Rehabilitation of the geriatric surgical patient: predicting needs and optimizing outcomes.

    PubMed

    Biffl, Walter L; Biffl, Susan E

    2015-02-01

    Geriatric surgical and trauma patients often require institutionalization following acute hospitalization, generally related to frailty. The potential need for rehabilitation can be assessed using various tools. Once the likelihood of rehabilitation needs is established, early involvement of the rehabilitation team is warranted. Rehabilitation interventions can be initiated during acute hospitalization, and even in the intensive care unit. The rehabilitation team addresses a tremendous spectrum of issues, and targeted interventions are carried out by various team members. There are many gaps in current knowledge of the benefits of rehabilitation interventions. Understanding common standardized assessment tools is important to assess the literature and advance the field.

  9. 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

  10. Data mining techniques for assisting the diagnosis of pressure ulcer development in surgical patients.

    PubMed

    Su, Chao-Ton; Wang, Pa-Chun; Chen, Yan-Cheng; Chen, Li-Fei

    2012-08-01

    Pressure ulcer is a serious problem during patient care processes. The high risk factors in the development of pressure ulcer remain unclear during long surgery. Moreover, past preventive policies are hard to implement in a busy operation room. The objective of this study is to use data mining techniques to construct the prediction model for pressure ulcers. Four data mining techniques, namely, Mahalanobis Taguchi System (MTS), Support Vector Machines (SVMs), decision tree (DT), and logistic regression (LR), are used to select the important attributes from the data to predict the incidence of pressure ulcers. Measurements of sensitivity, specificity, F(1), and g-means were used to compare the performance of four classifiers on the pressure ulcer data set. The results show that data mining techniques obtain good results in predicting the incidence of pressure ulcer. We can conclude that data mining techniques can help identify the important factors and provide a feasible model to predict pressure ulcer development.

  11. Sheet metal forming optimization by using surrogate modeling techniques

    NASA Astrophysics Data System (ADS)

    Wang, Hu; Ye, Fan; Chen, Lei; Li, Enying

    2017-01-01

    Surrogate assisted optimization has been widely applied in sheet metal forming design due to its efficiency. Therefore, to improve the efficiency of design and reduce the product development cycle, it is important for scholars and engineers to have some insight into the performance of each surrogate assisted optimization method and make them more flexible practically. For this purpose, the state-of-the-art surrogate assisted optimizations are investigated. Furthermore, in view of the bottleneck and development of the surrogate assisted optimization and sheet metal forming design, some important issues on the surrogate assisted optimization in support of the sheet metal forming design are analyzed and discussed, involving the description of the sheet metal forming design, off-line and online sampling strategies, space mapping algorithm, high dimensional problems, robust design, some challenges and potential feasible methods. Generally, this paper provides insightful observations into the performance and potential development of these methods in sheet metal forming design.

  12. 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

  13. [The Omega "Omega" pulley plasty: a new technique for the surgical management of the De Quervain's disease].

    PubMed

    Bakhach, J; Sentucq-Rigal, J; Mouton, P; Boileau, R; Panconi, B; Guimberteau, J-C

    2006-02-01

    The Omega "Omega" pulley plasty: a new technique for the surgical management of the De Quervain's disease. The De Quervain tenosynovitis is an inadequacy into the first extensor compartment between the osteo-fibrous tunnel and the tendons. This mechanical conflict generates a tenosynovitis of the extensor pollicis brevis and the abductor pollicis longus tendons. This is generally expressed by a tenderness on the radial side of the wrist over the radial styloid process. The medical management consists on corticoids infiltrations of the first extensor compartment, the avoidance of repetitive and stress movements of the first ray with the use of a rest splint. The surgical approach is considered with the recurrence of the painful symptoms. This well-known pathology is reputated to require a simple section of the pulley. Our post-operative complications have been reported in the literature of this classical surgical solution. These complications concern an incomplete release of the extensor pollicis brevis and the abductor pollicis longus tendons particularly when an extensor sub-compartment exists and was overlooked, an irritation of the collateral branches of the sensitive radial nerve or the occurrence of a nevroma after a nerve injury and the most serious complication is a palmar subluxation of the extensor tendons which can occur with the thumb extended and the wrist flexed. In rare cases, this subluxation can be really painful and requires a surgical management with secondary reconstruction of the pulley. This reconstruction necessitates distal pedicle flaps from the dorsal retinaculum or the brachioradialis tendon. To prevent these complications, Codega and Kapandji described techniques of reconstruction of the pulley after its release. More recently, Le Viet reported a procedure using the anterior flap of the pulley; fixed to the dermis it will work as a barrier and maintain the tendons sliding on the radial styloid groove. These techniques require to divide

  14. 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.

  15. Sensitivity of knee soft-tissues to surgical technique in total knee arthroplasty.

    PubMed

    Schirm, Andreas C; Jeffcote, Benjamin O; Nicholls, Rochelle L; Jakob, Hilaire; Kuster, Markus S

    2011-06-01

    Restricted range of motion and excessive laxity are both potential complications of total knee arthroplasty (TKA). During TKA surgery, the surgeon is frequently faced with the question of how tightly to implant the prosthesis. The most common method of altering implantation tightness is to vary the thickness of the polyethylene inlay after the bone cuts have been made and the trial components inserted. We have sought to quantify how altering the polyethylene thickness may affect post-operative soft tissue tension for a range of prosthetic designs. Four different prosthetic designs were implanted into fresh-frozen cadaveric knee joints. All four designs were implanted in the standard manner, with a 100 Newton distraction force used to set soft tissue balance. The tibiofemoral force was then recorded at 15° intervals throughout the passive flexion range. After the standard implantation of each prosthesis, the tibial component was raised or lowered to mimic increasing and decreasing the polyethylene thickness by 2mm and the force measurements repeated. Tibiofemoral force in extension correlated with implantation tightness for all prosthesis designs. Between 15° and 90° of knee flexion, all four designs were insensitive to changes in implantation tightness. Beyond 90° the effect was more notable in rotating platform mobile-bearing and cruciate-retaining prostheses than in posterior-stabilised mobile-bearing designs. The findings of this research may be useful in assisting surgical decision-making during the implantation of TKA prostheses.

  16. Current concepts in plasticity and nerve transfers: relationship between surgical techniques and outcomes.

    PubMed

    Socolovsky, Mariano; Malessy, Martijn; Lopez, Dan; Guedes, Fernando; Flores, Leandro

    2017-03-01

    OBJECTIVE Neuroplasticity is analyzed in this article as the capacity of the CNS to adapt to external and internal stimuli. It is being increasingly recognized as an important factor for the successful outcome of nerve transfers. Better-known factors are the number of axons that cross the coaptation site, the time interval between trauma and repair, and age. Neuroplasticity is mediated initially by synaptic and neurotransmitter changes. Over time, the activation of previously existing but lowly active connections in the brain cortex contributes further. Dendritic sprouting and axonal elongation might also take place but are less likely to be prominent. METHODS The authors reviewed different factors that play roles in neuroplasticity and functional regeneration after specific nerve transfers. RESULTS The authors found that these different factors include, among others, the distance between cortical areas of the donor and receptor neurons, the presence versus absence of preexisting lowly active interneuronal connections, gross versus fine movement restoration, rehabilitation, brain trauma, and age. CONCLUSIONS The potential for plasticity should be taken into consideration by surgeons when planning surgical strategy and postoperative rehabilitation, because its influence on results cannot be denied.

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

    DTIC Science & Technology

    2007-06-01

    Yan Yang, Steven Haker , and Allen Tannenbaum Abstract—Image morphing, or image interpolation in the time domain, deals with the metamorphosis of one...of Technology, Atlanta, GA 30332 USA (e-mail: zlzl@ece.gatech.edu; zhulei1976@hotmail.com; yan.yang@gatech.edu; tannenba@ece.gatech.edu). S. Haker is...with the Surgical Planning Laboratory, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115 USA (e-mail: haker @bwh.harvard.edu

  18. Repositioning template for mandibular reconstruction with fibular free flaps: an alternative technique to pre-plating and virtual surgical planning.

    PubMed

    Berrone, M; Crosetti, E; Succo, G

    2014-08-01

    Oral malignancies involving the mandibular bone require a complex reconstructive plan. Mandibular reconstruction with a fibular free flap is currently considered the best choice for functional and aesthetic rehabilitation after oncological surgery. This flap can be modelled with multiple osteotomies and can provide bone, muscle and skin for composite reconstruction. One of the most delicate aspects of mandibular reconstruction is the technique of bone modelling; the risk of prolonging the period of ischaemia and not restoring the correct maxillomandibular and occlusal relationships can ultimately lead to a higher rate of complications as well as poor aesthetic and functional results. Recently, there has been rising interest in virtual surgical planning and computer-assisted mandibular reconstruction in pre-operative planning; however, this is not always possible because of the costs involved and the set-up time for the entire procedure. In this paper, we present a simple and inexpensive technique for fibular free flap modelling and repositioning after segmental resection of the mandible; the technique entails the pre-operative preparation of a resin repositioning template on a stereolithographic model. This technique has been successfully applied in four cases: two cases underwent resection involving only the mandibular body, one case involving the mandibular body and symphysis and one case in which a ramus to ramus resection was performed. In this preliminary report, we show that the resin repositioning template is an easy, safe and useful tool for mandibular reconstruction with a fibular free flap.

  19. Surgical technique: establishing a pre-clinical large animal model to test aortic valve leaflet substitute

    PubMed Central

    Knirsch, Walter; Cesarovic, Niko; Krüger, Bernard; Schmiady, Martin; Frauenfelder, Thomas; Frese, Laura; Dave, Hitendu; Hoerstrup, Simon Philipp; Hübler, Michael

    2016-01-01

    To overcome current limitations of valve substitutes and tissue substitutes the technology of tissue engineering (TE) continues to offer new perspectives in congenital cardiac surgery. We report our experiences and results implanting a decellularized TE patch in nine sheep in orthotropic position as aortic valve leaflet substitute. Establishing the animal model, feasibility, cardiopulmonary bypass issues and operative technique are highlighted. PMID:28149571

  20. Impaction bone grafting and cemented stem revision in periprosthetic hip fractures: a novel surgical technique.

    PubMed

    Dearden, Paul M; Bobak, Peter P; Giannoudis, Peter V

    2014-01-01

    With an ageing population, and increasing longevity of hip arthroplasty prostheses, the incidence of periprosthetic femoral fractures is rising. We present a simple and easily reproducible technique for reduction of any periprosthetic fracture that requires bone graft augmentation. This method facilitates impaction bone grafting to reconstitute lost bone stock and revision using a cemented implant.

  1. Hallux valgus: comparative study between two surgical techniques of proximal addition osteotomy

    PubMed Central

    Lara, Luiz Carlos Ribeiro; de Araujo, Bruno Vierno; Franco, Nelson; Hita, Roberto Minoru

    2012-01-01

    OBJECTIVE: To clinically and radiographically compare the results of treatment of hallux valgus, by two addition osteotomy techniques: one using resected exostosis, and the other using a plate fixation for addition wedge. METHODS: We evaluated 24 feet of 19 patients, mean age 51.3 years, affected by hallux valgus, with a mean follow-up of 50.1 months. 13 feet underwent addition osteotomy with resected exostosis (AORE) and 11 patients (11 feet) underwent addition osteotomy with plate (AOP). The AOFAS score, intermetatarsal 1 and 2 angles, and hallux valgus angle were evaluated before and after surgery. RESULTS: In the AORE technique, the mean preoperative AOFAS was 46.6, with IMA 14o and HVA 32o, while in the postoperative AOFAS it was 81.3, with IMA 9o and HVA 25o, and 92.3% satisfactory results. In the AOP technique, the mean preoperative AOFAS was 42.1, with IMA 15o and HVA 29o while in the postoperative AOFAS it was 77.4, with IMA 11o and HVA 23o and 81.8% of satisfactory results. CONCLUSIONS: Both techniques proved to be effective in the treatment of hallux valgus, both clinically and radiografically, with no statistical difference between them. Level of evidence III, Retrospective comparative study. PMID:24453631

  2. Optimizing cerebrovascular surgical and endovascular procedures in children via personalized 3D printing.

    PubMed

    Weinstock, Peter; Prabhu, Sanjay P; Flynn, Katie; Orbach, Darren B; Smith, Edward

    2015-07-31

    OBJECT Despite the availability of multiplanar imaging, understanding relational 3D anatomy for complex cerebrovascular lesions can be difficult. A 3D printed model allows for instantaneous visualization of lesional anatomy from all perspectives, with the added ability to simulate operative approaches with tactile feedback. The authors report their experience with customized 3D printed models of pediatric cerebrovascular lesions as an educational and clinical tool for patients, trainees, and physicians. METHODS Via an "in-house" 3D print service, magnetic resonance imaging (MRI) and computerized tomography (CT) studies of pediatric patients with arteriovenous malformations (AVMs) were processed with specialized software, and regions of interest were selected by the surgical/endovascular team. Multiple models for each patient were then printed on a 3D printer, with each construct designed to illustrate different aspects of the specific lesion. Intraoperative validation of model fidelity was performed using perioperative imaging, surgical filming, and post hoc analysis of models with intraoperative photography. RESULTS Four cases involving pediatric patients (ages 0-16 years) were studied for initial proof of principle. Three of the patients had AVMs and one had a vein of Galen malformation (VOGM). The VOGM was embolized successfully and the AVMs were resected without complication. In the AVM cases, intraprocedural imaging and photography were performed and verified millimeter-level fidelity of the models (n = 5, 98% concordance, range 94%-100% with average of < 2 mm variation in the largest AVM [6-cm diameter]). The use of 3D models was associated with a 30-minute reduction in operative time (12%) in 2 cases when they were compared with matched controls as a feasibility study. CONCLUSIONS Patient-specific 3D printed models of pediatric cerebrovascular conditions can be constructed with high fidelity. This proof-of-principle series demonstrates, for the first time

  3. The clinical study of the optimalization of surgical treatment and the traditional Chinese medicine intervention on palmar hyperhidrosis.

    PubMed

    Yang, Yong; Yan, Zhikun; Fu, Xiaoqing; Dong, Liwen; Xu, Linhai; Wang, Jun; Cheng, Genmiao

    2014-11-01

    To analyze the efficacy of different surgical methods in treating palmar hyperhidrosis and the compensatory hyperhidrosis after surgery and to observe the efficacy of "Energy-boosting and Yin-nourishing anti-perspirant formula" on postsurgical hyperhidrosis patients. Two-hundred patients were randomly assigned to groups A (Chinese and Western medicine, T4 transection plus "Energy-boosting and Yin-nourishing anti-perspirant formula") and B (Western medicine, T4 transection). The surgical efficiency, recurrence rate, compensatory hyperhidrosis, and the long-term life quality were compared. Another 100 cases (group C, T2 transection) were analyzed as a control group. After surgery, the palmar hyperhidrosis and armpit sweating were relieved in all the three group patients and in 34 % of patients combined with plantar hyperhidrosis, the symptoms were relieved. Transient palmar hyperhidrosis was found in three cases at day 2 to day 5 postoperatively. One case of Horner's syndrome and one case recurrence were found in group C patients. The compensatory sweating of various degrees occurred in all the three groups. There were 25, 24, and 43 cases in groups A, B, and C, respectively. There is a significant difference between groups C, A, and B. The compensatory sweating in 13 cases of group A and four cases of group B had different degrees of improvement in the follow-up 6 months after surgery. There is a significant difference. Thoracoscopic bilateral T4 sympathetic chain and the Kuntz resection are the optimized surgical treatments for the palmar hyperhidrosis. "Energy-boosting and Yin-nourishing anti-perspirant formula" is effective in treating the postoperative compensatory sweating.

  4. 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

  5. Laparoscopic loop colostomy using an esophageal retractor and a penrose drain: surgical technique.

    PubMed

    Sabbagh, Raja; Rafiq, Amil; Familua, Oluwamayowa; Donaldson, Brian

    2013-10-01

    Laparoscopic Loop colostomy has been described in the literature as a safe and useful minimally invasive technique. It is indicated in patients with large perineal wounds requiring fecal diversion, obstructing lesions of the distal colon or rectum. The purpose of this article is to describe a modified version of this procedure which was used by 1 surgeon in our institution on a series of 5 patients. In this method, an esophageal retractor and Penrose drain are used to tent up and exteriorize the desired segment of colon to be used for the colostomy site. Results were that all 5 were completed laparoscopically and there were no complications. In conclusion, this variation in the technique has been useful in our institution and others may find it worthwhile to consider.

  6. A new surgical technique for medial collateral ligament balancing: multiple needle puncturing.

    PubMed

    Bellemans, Johan; Vandenneucker, Hilde; Van Lauwe, Johan; Victor, Jan

    2010-10-01

    In this article, we present our experience with a new technique for medial soft tissue balancing, where we make multiple punctures in the medial collateral ligament (MCL) using a 19-gauge needle, to progressively stretch the MCL until a correct ligament balance is achieved. Ligament status was evaluated both before and after the procedure using computer navigation and mediolateral stress testing. The procedure was considered successful when 2 to 4-mm mediolateral joint line opening was obtained in extension and 2 to 6 mm in flexion. In 34 of 35 cases, a progressive correction of medial tightness was achieved according to the above described criteria. One case was considered overreleased in extension. Needle puncturing is a new, effective, and safe technique for progressive correction of MCL tightness in the varus knee.

  7. Avulsion of the anterior medial meniscus root: case report and surgical technique.

    PubMed

    Feucht, Matthias J; Minzlaff, Philipp; Saier, Tim; Lenich, Andreas; Imhoff, Andreas B; Hinterwimmer, Stefan

    2015-01-01

    Injuries of the meniscus roots have become increasingly recognised as a serious pathology of the knee joint. However, the current available literature focuses primarily on posterior meniscus root tears. In this article, a case with an isolated avulsion of the anterior medial meniscus root is presented, and a new arthroscopic technique to treat this type of injury is described. The anterior horn of the medial meniscus was sutured with a double-looped nonabsorbable suture and reattached to the tibial plateau using a knotless suture anchor. This technique may also be useful to treat avulsion injuries of the anterolateral or posteromedial meniscus root, and symptomatic subluxation of the medial meniscus in case of a variant insertion anatomy with an absent attachment of the anterior horn of the medial meniscus to the tibial plateau. Level of evidence V.

  8. Arrow shaft injury of the wrist and hand: case report, management, and surgical technique.

    PubMed

    Launikitis, Robert A; Viegas, Steven F

    2009-01-01

    A case of accidental, self-inflicted injury to the hand from a hollow carbon shaft arrow which broke in its midshaft while attempting to shoot the arrow from a compound bow is presented. Basic knowledge of low velocity gunshot wounds and arrow injuries was applied in the treatment of this injury along with a unique management technique. The outcome, including hand function was good without any functional loss.

  9. 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

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

    PubMed

    Merolla, G; Nastrucci, G; Porcellini, G

    2013-01-01

    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.

  11. Ilizarov techniques with limited adjunctive surgical procedures for the treatment of preadolescent recurrent or neglected clubfeet.

    PubMed

    Khanfour, Ashraf A

    2013-05-01

    When choosing the Ilizarov technique for the treatment of recurrent or neglected clubfeet deformity, there was a consensus on the treatment of 3-8-year-old children by the soft-tissue distraction 'bloodless method' either alone or with an adjunctive-limited soft tissue release; whereas, in older children, adjunctive osteotomies were required. Major foot osteotomies such as V, U, Y, or supramalleolar types were established for patients after puberty when the foot bones become fully ossified. So, children falling in the age group between 8 and 13 years (preadolescents) represents a transitional growing stage that has its identity that makes carrying out major foot osteotomies unsuitable. Twenty-five feet in 21 patients with a mean age at the time of operation of 10.9 years (range, 9-13 years) with recurrent or neglected clubfeet deformity who presented to the orthopedic department at Alexandria (Egypt) between February 2004 and December 2008 were treated with the Ilizarov technique combined with adjunctive limited bony and/or soft-tissue procedures as will be discussed. After a mean follow-up period of 3.6 years (range, 2-7 years), 21 children showed good results, four children showed fair results, and no poor results were recorded. No major complications were reported. The Ilizarov technique with limited bony and/or soft-tissue procedures can be considered as a suitable, convenient, efficient, and successful salvage procedure for preadolescent recurrent or neglected clubfeet.

  12. Surgical correction of blepharoptosis using a modified levator aponeurosis-Müller muscle complex reinsertion technique.

    PubMed

    Liu, Haipeng; Shao, Ying; Zhang, Duo

    2014-01-01

    The purpose of this study was to evaluate the outcomes after ptosis correction surgery using a modified levator aponeurosis-Müller muscle complex reinsertion technique. In this clinical study, 75 eyelids of 49 patients with congenital blepharoptosis were treated with the modified technique. The results, including complications, were followed up and evaluated. Operation was performed via anterior transcutaneous incision. After separating the preseptal orbicularis oculi muscle, the levator complex, including Müller muscle and the levator aponeurosis, was visualized. The levator complex was cut into 2 parts at the top of the conjunctival fornix to create an upper portion and a lower portion. The detached lower portion of the complex flap combined with the tarsal plate was advanced superiorly and reinserted into the posterior aspect of the upper portion of the complex flap by using 3 horizontal mattress sutures. Preoperative ptosis severity was compared with the degree of ptosis correction using the Cochran-Mantel-Haenszel test. Preoperative levator function was compared with the degree of ptosis correction and the postoperative levator function using Fisher exact test for paired data. Sufficient postoperative correction of ptosis was achieved in 78.7% of eyelids. Postoperative levator function of more than 4 mm was achieved in 82.7% of all eyelids that underwent surgery. We conclude that the modified levator aponeurosis-Müller muscle complex reinsertion technique is effective for correcting congenital blepharoptosis, especially in patients with fair to good (>4 mm) preoperative levator function.

  13. The Platform Switching Approach to Optimize Split Crest Technique

    PubMed Central

    Sammartino, G.; Cerone, V.; Gasparro, R.; Riccitiello, F.; Trosino, O.

    2014-01-01

    The split crest technique is a reliable procedure used simultaneously in the implant positioning. In the literature some authors describe a secondary bone resorption as postoperative complication. The authors show how platform switching can be able to avoid secondary resorption as complication of split crest technique. PMID:25165586

  14. 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,…

  15. Results of surgical techniques for re-innervation of the triceps as additional procedures for patients with upper root injuries.

    PubMed

    Flores, L Pretto

    2013-03-01

    Patients with injuries restricted to the upper and middle trunks of the brachial plexus may obtain recovery of elbow extension via the lower trunk, which makes it difficult to assess the real effect of interventions to restore the triceps function in such cases. This study aimed to determine the impact of surgical strategies for re-innervation of the triceps in individuals with partial injuries of the brachial plexus. Patients were divided into two groups. Group 1 consisted of 21 participants in whom the surgery included one technique for re-innervation of elbow extension. In this group, six different extra- or intra-plexal donors were targeted to one of the motor branches of the triceps muscle. Group 2 was composed of 24 controls in which the reconstruction did not include any intervention for recovering triceps function. The individuals who underwent intervention for re-innervation of the triceps obtained significantly better outcomes for elbow extension than the controls.

  16. A new surgical technique using steel suture for trans-scleral fixation of posterior chamber intraocular lenses

    PubMed Central

    Ram, Jagat; Gupta, Nishant; Chaudhary, Manish; Verma, Neelam

    2013-01-01

    Background: A new emerging complication of trans-scleral fixation of posterior chamber (PC) intraocular lens (IOL) with polypropylene suture is high rates of spontaneous dislocation of the IOL due to disintegration or breakage of suture. Materials: We report a new surgical technique of trans-scleral fixation of posterior chamber intraocular lens (SF PCIOL) with steel suture to eliminate the complication of dislocation of IOL fixed with polypropylene suture in one adult and a child. Results: We successfully achieved stable fixation and good centration of IOL after SF PCIOL with steel suture in these patient having inadequate posterior capsular support. Both eyes achieved best corrected visual acuity 20/40 at 18 months follow-up. Conclusions: Steel suture is a viable option for trans-scleral fixation of posterior chamber intraocular lens. PMID:23619504

  17. 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.

  18. 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

  19. [Widened forwarding total laryngectomy ("squared laryngectomy"). Hints of surgical techniques and personal experience].

    PubMed

    Croce, A; Moretti, A; Bianchedi, M; Neri, G; Falcone, G

    1995-10-01

    Primitive T4 laryngeal neoplasms with anterior invasion and neoplasm recurring after partial and subtotal intervention often invade the soft prelaryngeal tissues and in these cases the neoplastic illness can be no longer be controlled be "organ surgery". The widened forwarding total laryngectomy, "squared" or "carrè" laryngectomy according to some Authors of French School, is a surgical procedure not "on an organ" but "in an area" or "region" which proposes to delete, in one step, the larynx, the bone hyoid, the fasciae and the prelaryngeal muscles, the thyroid gland and, if necessary, a more or less large quantity of anterior cervical skin. If the removal involves a vast cutaneous area, it is necessary to mend the loss of substance by wrapping around a miocutaneous flap of pectoralis mayor muscle. In the last five years, 4 male patients, between 48 and 73 years, were treated with widened forwarding total laryngectomy. They were all carriers of epidermoid laryngeal carcinomas with various degrees of differentation: primitive in one patients, recidivist after performance of partial (cordectomy) and subtotal (two Labayle) surgery in the other three patients. In the only case of T4 primitive laryngeal neoplasm it was necessary to carry out a functional neck dissection bilaterally. Loss of substance always required the use of a miocutaneous flap of pectoralis mayor muscle except in one patient in which the removal of the prelaryngeal tissues was limited and therefore it was possible to make a direct seam. We always completely removed the thyroid gland, the prelaryngeal muscular system and skin of the preceding stomy (in the Labayle) sparing, on the other hand, the hyoid bone. Only one patient, who died due to recurrence a year after surgery, underwent complemental percutaneous radiotherapy. At present, three patients are alive and NED: one after 5 years, the others are in excellent conditions although the follow-up is still brief. According to our experience, we can

  20. An optimal GPS data processing technique for precise positioning

    NASA Technical Reports Server (NTRS)

    Wu, Sien-Chong; Melbourne, William G.

    1993-01-01

    A mathematical formula to optimally combine dual-frequency GPS pseudorange and carrier phase (integrated Doppler) data streams into a single data stream is derived in closed form. The data combination reduces the data volume and computing time in the filtering process for parameter estimation by a factor of 4 while preserving the full data strength for precise positioning. The resulting single data stream is that of carrier phase measurements with both data noise and bias uncertainty strictly defined. With this mathematical formula the single stream of optimally combined GPS measurements can be efficiently formed by simple numerical calculations. Carrier phase ambiguity resolution, when feasible, is strengthened due to the preserved full data strength with the optimally combined data and the resulting longer wavelength for the ambiguity to be resolved.

  1. 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

  2. Upper eyelid retraction in Graves' ophthalmopathy: a new surgical technique and a study of the abnormal levator muscle.

    PubMed Central

    Small, R G

    1988-01-01

    A new surgical procedure, the proximal levator technique, achieves recession of the retracted upper eyelid in Graves' ophthalmopathy by sectioning the levator muscle proximal to Whitnall's ligament and fixing eyelid position with sutures that permit postoperative adjustment. This technique deserves further study. Enlargement of the proximal levator muscle in Graves' eye disease is shown on orbital CT scans and is found at surgery when the proximal levator technique is employed. Histologic and morphometric studies demonstrate increased levator muscle fiber size as well as increased extracellular volume. These findings suggest that levator muscle hypertrophy is important in the pathogenesis of upper eyelid retraction in Graves' ophthalmopathy. Images FIGURE 2 A FIGURE 3 A FIGURE 3 B FIGURE 3 C FIGURE 3 D FIGURE 4 A,B FIGURE 4 C,D,E FIGURE 4 F,G FIGURE 6 A FIGURE 6 B FIGURE 7 A FIGURE 7 B FIGURE 8 A FIGURE 8 B FIGURE 9 A FIGURE 9 B FIGURE 10 A FIGURE 10 B FIGURE 11 A FIGURE 11 B FIGURE 12 A FIGURE 12 B FIGURE 13 A FIGURE 13 B FIGURE 14 A FIGURE 14 B FIGURE 15 A FIGURE 15 B FIGURE 16 A FIGURE 16 B FIGURE 17 A FIGURE 17 B FIGURE 18 A FIGURE 18 B FIGURE 19 A FIGURE 19 B FIGURE 20 FIGURE 21 FIGURE 22 FIGURE 23 FIGURE 24 FIGURE 25 FIGURE 26 FIGURE 27 FIGURE 28 FIGURE 29 FIGURE 30 FIGURE 31 FIGURE 32 PMID:2979032

  3. [Surgical technique of saphenous vein harvesting using a Cusco vaginal speculum].

    PubMed

    Kikuchi, Keita; Suzuki, Kotaro; Endo, Yoshiki; Matsuyama, Takayoshi; Osaka, Shin-ichi; Kurata, Atsushi

    2014-11-01

    We used Cusco vaginal speculum in harvesting saphenous vein graft (SVG) as an assist device for making a skin tunnel. After making 2 incisions of 3 to 4 cm, the SVG was dissected in a usual procedure. Then Cusco vaginal speculum was inserted into the skin tunnel between the 2 incisions. The SVG was dissected in a usual fashion under direct vision with the speculum. This procedure requires only small incisions, short learning curve and low cost. The new technique using Cusco vaginal speculum can be a reliable option for harvesting SVG.

  4. Tricuspid regurgitation following left-sided valve surgery: echocardiographic evaluation and optimal timing of surgical treatment.

    PubMed

    Izumi, Chisato

    2015-03-01

    Severe tricuspid regurgitation may often appear and progress late after left-sided valve surgery without left-sided valve dysfunction, significant left heart failure, and pulmonary hypertension. The clinical features, echocardiographic evaluation, treatment, and prognosis of this disease entity have been discussed, but data is limited compared with left-sided valve diseases. Tricuspid annular dilatation associated with atrial fibrillation and right ventricular dysfunction strongly relate to development of isolated tricuspid regurgitation late after left-sided valve surgery. Three-dimensional evaluation may be useful in evaluating tricuspid valve anatomy in more detail. Better prognosis in patients undergoing surgical treatment for severe isolated tricuspid regurgitation than those who were treated medically has been reported; however, the timing of isolated tricuspid valve surgery is often too late. Right ventricular function is a key word for determining the timing of isolated tricuspid valve surgery; however, it is difficult to evaluate by conventional echocardiography. One of the serious issues in the future will be how to accurately evaluate right ventricular function.

  5. The effects of surgical preparation techniques and implant macro-geometry on primary stability: An in vitro study

    PubMed Central

    Severino, Marco; Rastelli, Claudio; Bernardi, Sara; Caruso, Silvia; Galli, Massimo; Lamazza, Luca; Di Paolo, Carlo

    2017-01-01

    Background The attainment of a good primary stability is a necessary condition to ensure the success of osseointegration in implantology. In type IV cancellous bone, however, it is possible that a reduced primary stability can lead to an increased rate of failure. The aim of this study was therefore to determine, with the help of the resonance frequency (Osstell mentor), which technique of implant site preparation (piezo surgery, conventional, under-preparation, bone compaction, osteodistraction) and macro-geometry is able to improve implant stability in type IV cancellous bone. Material and Methods 10 pig ribs were prepared with a surgical pre-drilled guide, calibrated for a correct implant positioning. On each rib, 5 implant sites (one for each technique) were prepared. Successively, 50 conical implants (Tekka Global D) were inserted and measured with the resonance frequency to evaluate the primary stability. Data collected were analyzed by analysis of variance (ANOVA) to test whether the Implant Stability Quotient (ISQ) values of the five techniques were significantly different. Results The results showed that no significant differences among the ISQ values of the five techniques used were found. Also, no significant differences in the macro-geometry of the two types of compared implants were observed. However, the macro-geometry of Tekka implants, characterized by a double condensing thread, seems to provide greater ISQ values than those of single thread implants when using the same technique. Conclusions In light of these preliminary data, it is conceivable that in cases of reduced stability, such as those occurring with a type IV bone, all means ameliorating the primary stability and accelerating the osseointegration can be utilized. Key words:Implant primary stability, resonance frequency analysis, implant site preparation. PMID:28160577

  6. Thoracoscopic sympathicotomy for hyperhidrosis--surgical technique, complications and side effects.

    PubMed

    Göthberg, G; Drott, C; Claes, G

    1994-01-01

    Thoracic sympathectomy is a very effective treatment of palmar hyperhidrosis. The described endoscopic technique has given good primary results in 99% of patients. After another session with this type of "minimal invasive surgery" 100% of the hands were satisfactorily dry. The hospital stay is just one post-operative day and the sick-leave is about a week. The drawbacks are minimal. Pain is tolerable and only eight patients needed a post-operative Bülau-drainage because of pneumothorax or bleeding. About 50% of patients experience a compensatory increased sweating of the trunk, but this is related to a warm environment and regulation of body temperature and seems to decrease with time. This technique makes it possible to treat all those suffering from palmar hyperhidrosis which can be a substantial, but underestimated handicap. To meet this kind of patient after a successful operation is extremely satisfying even for the surgeon. The post-operative wet and cold hand has immediately post-operatively become warm and dry.

  7. 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

  8. [Kirschner wire transfixation of unstable ankle fractures: indication, surgical technique and outcomes].

    PubMed

    Marvan, J; Džupa, V; Bartoška, R; Kachlík, D; Krbec, M; Báča, V

    2015-01-01

    , in the group with temporary transfixation, no radiographic evidence of ankle osteoarthritis was recorded in 25 (42%) patients. While tibiofibular synostosis was recorded in only few patients (9%) of the group with one-stage osteosynthesis, it showed a high occurrence in the group with temporary transfixation (35%). The patients with one-stage osteosynthesis (188/68%) had a higher proportion of excellent outcomes measured on the Olerund-Molander ankle scoring scale than the other two groups (temporary transfixation, 47%; definitive transfixation,10%); in both cases the difference was significant (p < 0.001 and p = 0.003, respectively). DISCUSSION In this study the morphological and clinical aspects of surgically treated ankle fractures were assessed. The patients with one-stage osteosynthesis were compared with those treated by temporary or definitive transfixation. The majority of patients undergoing temporary transfixation had a fractured posterior margin of the tibia and major ankle joint dislocation, which suggested serious injuries to bone and ligament structures. Generally, the use of only two K-wires inserted through the calcaneus and talus into the distal tibia is recommended. Patients with K-wire transfixation usually require a longer hospital stay because of the serious nature of their injuries. CONCLUSIONS The therapy of choice for unstable ankle fractures is one-stage osteosynthesis. Temporary transfixation is an effective method of primary management when an unstable fracture cannot be treated by definitive osteosynthesis at the early stage due to local or general health conditions of the patient. The temporary transfixation provides good alignment of the ankle joint necessary for successful healing of soft tissues. A higher occurrence of post-traumatic ankle osteoarthritis, ossification and distal tibiotalar synostosis found in the patients treated by temporary transfixation is more related to serious types of ankle fractures the patient had suffered

  9. Optimal Use of Wire-Assisted Techniques and Precut Sphincterotomy

    PubMed Central

    Lee, Tae Hoon; Park, Sang-Heum

    2016-01-01

    Various endoscopic techniques have been developed to overcome the difficulties in biliary or pancreatic access during endoscopic retrograde cholangiopancreatography, according to the preference of the endoscopist or the aim of the procedures. In terms of endoscopic methods, guidewire-assisted cannulation is a commonly used and well-known initial cannulation technique, or an alternative in cases of difficult cannulation. In addition, precut sphincterotomy encompasses a range of available rescue techniques, including conventional precut, precut fistulotomy, transpancreatic septotomy, and precut after insertion of pancreatic stent or pancreatic duct guidewire-guided septal precut. We present a literature review of guidewire-assisted cannulation as a primary endoscopic method and the precut technique for the facilitation of selective biliary access. PMID:27642848

  10. Assessment of scapular morphology and surgical technique as predictors of notching in reverse shoulder arthroplasty.

    PubMed

    Sabesan, Vani; Callanan, Mark; Sharma, Vinay; Wiater, J Michael

    2015-05-01

    There has been increased focus on understanding risk factors for scapular notching in reverse shoulder arthroplasty (RSA). We conducted a study to evaluate the scapular notching index and other factors associated with the occurrence of scapular notching. Ninety-one patients treated with primary RSA were followed for a minimum of 24 months. Patients' radiographic assessments were grouped by Nerot grade of scapular notching (group 1, grades 0 and 1; group 2, grades 2, 3, 4). Group mean differences were compared for preoperative scapular neck angle (SNA), prosthesis-scapular neck angle (PSNA), peg glenoid rim distance (PGRD), notching index, and clinical outcomes. There was no significant difference in mean (SD) notching index between group 1, 31.8 (4.4), and group 2, 33.1 (7.3), and there were no significant differences in SNA (102.8° vs 105.4°; P=.3), PSNA (125.8° vs 125.4°; P=.82), PGRD (15.4 vs 16.8 mm; P=.47), or clinical outcomes between the groups. Our results suggest that Grammont-style prostheses have a higher rate of notching regardless of optimal PGRD and variations in PSNA. Perhaps with certain scapular morphology, prosthetic design may be a more significant contributor to notching.

  11. Laparoscopic surgical technique to facilitate management of high anorectal malformations – report of seven cases

    PubMed Central

    Murawski, Maciej; Łosin, Marcin; Królak, Marek; Czauderna, Piotr

    2011-01-01

    Anorectal malformations (ARMs) occur in approximately 1 per 5000 live births. The most commonly used procedure for repair of high ARMs is posterior sagittal anorectoplasty (PSARP). This operation is performed entirely through a perineal approach. The first report of laparoscopically assisted anorectal pull-through (LAARP) for repair of ARMs was presented by Georgeson in 2000. The aim is presenting early experience with laparoscopically assisted anorectal pull-through technique in boys with high anorectal malformations. In the last 5 years 7 boys (9 months to 2 years old) with high ARMs were operated on using the LAARP technique. Laparoscopically the rectal pouch was exposed down to the urethral fistula, which was clipped and divided. Externally, the centre of the muscle complex was identified using an electrical stimulator. In the first 4 patients after a midline incision of 2 cm at the planned anoplasty site, a tunnel to the pelvis was created bluntly and dilated with Hegar probes under laparoscopic control. In the last 3 boys a minimal PSARP was done creating a channel into the pelvis. The separated rectum was pulled down and sutured to the perineum. Laparoscopic mobilization of the rectal pouch and fistula division was possible in all cases. There were no intraoperative complications except one ureteral injury. Patients were discharged home on post-operative day 5 to 7. The early results prove that LAARP, an alternative option to PSARP for treatment of imperforate anus, offers many advantages, including excellent visualization of the pelvic anatomical structures, accurate placement of the bowel into the muscle complex and a minimally invasive abdominal and perineal incision. It allows for shorter hospital stay and faster recovery. However, to compare the functional results against the standard procedure (PSARP), longer follow-up of all patients is necessary. PMID:23255974

  12. Percutaneous Cannulated Compression Screw Osteosynthesis in Phalanx Fractures: The Surgical Technique, the Indications, and the Results

    PubMed Central

    Kisch, Tobias; Wenzel, Eike; Mailänder, Peter; Stang, Felix

    2017-01-01

    Objective: Fractures of metacarpals and phalanges are very common fractures, and there are a lot of treatment modalities. The purpose of the study was to describe the technique of percutaneous fixation of phalangeal fractures using a cannulated compression screw fixation system and its results. Methods: We conducted a prospective clinical study on 43 patients with different types of phalangeal fractures undergoing a percutaneous cannulated compression screw osteosynthesis. Parameters such as average operation time and clinical outcome were evaluated postoperatively. Results: Forty-three patients were treated using a percutaneous cannulated compression screw fixation system for phalanx fractures of the proximal (n = 26), middle phalanx (n = 16), or distal phalanx (n = 1). All fractures healed after 6 to 8 weeks except in 1 patient with secondary loss of reduction occurring 2.5 weeks after surgery. No infections were observed. The mean total active motion values were 247.56° ±16.16° and 244.35° ± 11.61° for the intra-articular fracture and 251.25° ± 19.86° for the shaft fractures; the mean Disabilities of the Arm, Shoulder, and Hand (DASH) score 3 months after the surgery was 1.67 ± 2.74. Conclusions: The advantages of this technique are the avoidance of an open procedure requiring extensive soft-tissue dissection with the risks of tendon adhesions and the achievement of interfragmentary compression. Because of the interfragmentary compression, it is superior to simple K-wires. With regard to indications, our primary focus was on unicondylar proximal interphalangeal joint fractures, shaft fractures, and simple oblique 2-fragment fractures. PMID:28293333

  13. Safe microburst penetration techniques: A deterministic, nonlinear, optimal control approach

    NASA Technical Reports Server (NTRS)

    Psiaki, Mark L.

    1987-01-01

    A relatively large amount of computer time was used for the calculation of a optimal trajectory, but it is subject to reduction with moderate effort. The Deterministic, Nonlinear, Optimal Control algorithm yielded excellent aircraft performance in trajectory tracking for the given microburst. It did so by varying the angle of attack to counteract the lift effects of microburst induced airspeed variations. Throttle saturation and aerodynamic stall limits were not a problem for the case considered, proving that the aircraft's performance capabilities were not violated by the given wind field. All closed loop control laws previously considered performed very poorly in comparison, and therefore do not come near to taking full advantage of aircraft performance.

  14. Development and Application of Optimization Techniques for Composite Laminates.

    DTIC Science & Technology

    1983-09-01

    Table Page 1. Algorithm Performance ............. 40 2. Material Properties .............. 51 3. Comparison of Approximate Strain-Sphere to Tsai-Wu...constraint, based on "smeared" laminate properties . The optimization routines are coupled to a finite element code to update the stress state as the...failure criteria with a 4 ,- _ . ~ . - -. - ° - .l ’ ’ • -_ , . ,- .. - ,c." . . -. -.- : . . . . . . . .• r -"- - - complete set of laminate property

  15. Adaptive Optimization Techniques for Large-Scale Stochastic Planning

    DTIC Science & Technology

    2011-06-28

    cannot be kept longer than a few weeks. The decision maker must decide on blood - type substitutions that minimize the chance of future shortage. Because...optimal blood - type substitution is a large stochastic problem. Another application is managing water reservoirs. In this domain, an operator needs to decide...compatibility constraints among blood types , blood inventory management does not fit well the standard inventory control framework. In reservoir management

  16. 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.

  17. Single-Portal Versus Two-Portal Knee Arthroscopy: First Clinical Experience With a New Surgical Technique.

    PubMed

    Cooper, Daniel E

    2016-01-01

    This pilot study compared efficacy, morbidity, and complication rates with a new single-portal arthroscopy technique and traditional 2-portal knee arthroscopy. This prospective study evaluated 156 patients who underwent arthroscopic knee surgery, 106 with 2 portals and a traditional arthroscope and instruments and 50 with a single portal and newly designed arthroscopy instruments. Patients who had reconstructive procedures, microfractures, lateral release procedures, advanced osteoarthritis, and revision surgery were excluded, as were obese patients. The same surgeon performed all procedures, and the patient groups had no significant differences in sex, age, types of pathology, surgical treatment, medications given, or rehabilitation protocol. All patients were examined and completed questionnaires 1 week, 1 month, and 3 months postoperatively. The surgeon was blinded to the data. Follow-up was 100%. The single-portal technique was technically feasible for treatment of knee pathology in 49 of 50 patients. The 2-portal technique provided adequate treatment of knee pathology in all 106 cases. No difference was reported in pain level in the recovery room or on postoperative day 2. However, patients in the single-portal group reported less pain on day 4 (P=.04) and day 7 (P=.004) and were less likely to use oral narcotic analgesics (P=.0001). The single-portal group reported better function in activities of daily living at 1 month and less interference with sports participation at 3 months. Complication rates were no different in the 2 groups. The findings showed that the single-portal technique improved functional recovery at 1 month and 3 months postoperatively and may result in less morbidity in some parameters.

  18. Anterograde excision of a sublingual gland: new surgical technique for the treatment of ranulas.

    PubMed

    Liu, Zhigang; Wang, Bin

    2016-02-01

    Wharton's duct is dissected in a retrograde direction from the orifice of the duct to the hilum of the submandibular gland when the gland is being excised conventionally. Here we describe an anterograde technique, in which Wharton's duct is dissected in an anterograde direction from the hilum of the submandibular gland to the orifice of the duct. This prospective clinical study included 50 consecutive patients with ranulas who had anterograde excision of the sublingual gland between May 2012 and January 2015. The intraoral incision was similar to that for conventional excision. Wharton's duct and other important anatomical structures located in the space behind the sublingual gland were all identified at the beginning of the procedure, followed by anterograde dissection of Wharton's duct. After the glandular tissue lateral to the duct had been incised completely, the duct was exposed and the gland cut into two parts. Finally, the two parts were removed, and the ranula ruptured. The patients were followed up from 6 months-2 years. There were no complications. Anterograde excision of the sublingual gland is based on the anatomy, and this reduces the risk of complications after removal of a ranula.

  19. In vitro characterization of the technique of portal vein embolization by injection of a surgical glue

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Sandulache, Mihai-Cristinel; Lancon, Oceane; El Kadri Benkara, Khadija

    2012-11-01

    Partial embolization of the portal trunk by glue injection is a minimally invasive technique used in the case of malignant liver tumors. It is conducted few weeks prior to partial liver ablation, when the volume of the remnant liver section is too small to allow hepatectomy. The limitation of glue embolotherapy is that its clinical practice is based on empirical knowledge. The present objective is to study glue injection in a confined blood flow and investigate how the injection dynamics is coupled with glue polymerization. We first characterize polymerization under static conditions for various glue concentrations and then consider the influence of injection. An experimental setup reproduces the co-flow of two immiscible fluids. The glue mixture is injected through a capillary tube into a saline solution with the same ionic concentration, pH and viscosity as blood, flowing steadily in a straight cylindrical tube. The injected phase is visualized with a high-speed imaging system and results are compared with those obtained for non-reacting fluids. These experiments have enabled us to characterize the characteristic times of polymerization of the glue mixtures under static and dynamic conditions and understand how they affect the flow topology of the glue once injected. Biomechanics and Bioengineering Laboratory (UMR CNRS 7338).

  20. Surgical techniques: how I do it? The Reamer/Irrigator/Aspirator (RIA) system.

    PubMed

    Giannoudis, P V; Tzioupis, C; Green, J

    2009-11-01

    Although reamed intramedullary nailing has long been considered a safe procedure, pulmonary complications have been reported in some groups of patients. Concerns over fat embolisation, adult respiratory distress syndrome (ARDS), and sudden intraoperative death have prompted some authors to question whether the benefits of reaming are outweighed by its potential adverse effects to the patient. In response to these complications, recent evaluations have focused on alternative systems that reduce intramedullary pressure during reaming. The Reamer/Irrigator/Aspirator (RIA) system (Synthes, Inc., West Chester, PA) was developed as a simultaneous reaming and aspiration system to reduce the intramedullary pressure, heat generation, operating time, and systemic effects of reaming. It was designed with an aggressive one-pass reamer head which is connected to a hand-held reamer via a drive shaft, simultaneously irrigating and aspirating femoral canal contents during reaming, thus preventing thermal necrosis and fat embolisation. After its early use, investigators examined the "aspirate" captured by the RIA which appeared to be loaded with osteogenic substrates. This discovery revealed a second potential use for the RIA-a bone graft harvester. The different design characteristics and technicalities of the RIA system necessitate a deep and clear understanding of its technique, a meticulous preoperative planning and a strict adherence to its principles intraoperatively. We present our current approach to the use of the RIA system, including the preoperative planning, the details of the operative procedure, the pitfalls and the potential complications that could be encountered.

  1. Lumbar extracavitary corpectomy with a single stage circumferential arthrodesis: surgical technique and clinical series.

    PubMed

    Singh, Kern; Park, Daniel K

    2012-07-01

    Circumferential arthrodesis and reconstruction is necessary after a lumbar corpectomy in the setting of malignancy and infection. The advent of expandable cage technology now allows for safe anterior column reconstruction via a posterior approach with no transection and minimal retraction of the lumbar spinal nerve roots. Fifteen patients underwent a single-stage, circumferential corpectomy and anterior spinal reconstruction with an expandable cage via a midline, posterior, lateral lumbar extracavitary approach. Posterior segmental pedicle screw fixation and iliac crest bone graft was used in all cases. Fifteen lumbar extracavitary corpectomy nerve root-sparing procedures have been performed to date, with at least 1-year follow-up (12 tumors/3 infections). No patient suffered any neurological complications. One patient suffered from a postoperative myocardial infarction 10 days after the procedure. Two patients had medical complications that were treated without sequelae. We present a technical description and case series of patients undergoing a single-stage, circumferential corpectomy and anterior spinal reconstruction with an expandable cage via a midline, posterior, lateral lumbar extracavitary approach with at least 1-year follow-up. The technique is safe, technically feasible, and obviates an anterior approach in this oftentimes critically ill patient population.

  2. 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

  3. An optimized surgical approach for obtaining stable extracellular single-unit recordings from the cerebellum of head-fixed behaving mice

    PubMed Central

    White, Joshua J.; Lin, Tao; Brown, Amanda M.; Arancillo, Marife; Lackey, Elizabeth P.; Stay, Trace L.; Sillitoe, Roy V.

    2016-01-01

    Background Electrophysiological recording approaches are essential for understanding brain function. Among these approaches are various methods of performing single-unit recordings. However, a major hurdle to overcome when recording single units in vivo is stability. Poor stability results in a low signal-to-noise ratio, which makes it challenging to isolate neuronal signals. Proper isolation is needed for differentiating a signal from neighboring cells or the noise inherent to electrophysiology. Insufficient isolation makes it impossible to analyze full action potential waveforms. A common source of instability is an inadequate surgery. Problems during surgery cause blood loss, tissue damage and poor healing of the surrounding tissue, limited access to the target brain region, and, importantly, unreliable fixation points for holding the mouse’s head. New Method We describe an optimized surgical procedure that ensures limited tissue damage and delineate a method for implanting head plates to hold the animal firmly in place. Results Using the cerebellum as a model, we implement an extracellular recording technique to acquire single units from Purkinje cells and cerebellar nuclear neurons in behaving mice. We validate the stability of our method by holding single units after injecting the powerful tremorgenic drug harmaline. We performed multiple structural analyses after recording. Comparison with Existing Methods Our approach is ideal for studying neuronal function in active mice and valuable for recording single-neuron activity when considerable motion is unavoidable. Conclusions The surgical principles we present for accessing the cerebellum can be easily adapted to examine the function of neurons in other brain regions. PMID:26777474

  4. 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

  5. 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

  6. The Use of MMF Screws: Surgical Technique, Indications, Contraindications, and Common Problems in Review of the Literature.

    PubMed

    Cornelius, Carl-Peter; Ehrenfeld, Michael

    2010-06-01

    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.

  7. Semitendinosus and gracilis free muscle-tendon graft for repair of massive rotator cuff tears: surgical technique

    PubMed Central

    GIGANTE, ANTONIO; BOTTEGONI, CARLO; MILANO, GIUSEPPE; RICCIO, MICHELE; DEI GIUDICI, LUCA

    2016-01-01

    Massive rotator cuff tears are difficult to treat surgically due to retraction, degeneration and fraying of the ends of torn tendons, severe fatty infiltration and atrophy of the respective muscles. Procedures developed to close the gap between the rotator cuff and the greater tuberosity of the humerus, such as soft tissue release may be inadequate for large tears. Human or porcine dermal allografts still have uncertain benefits, and tendon transfers seem to be associated with poor outcomes, donor site morbidity and altered mechanics. Reverse total shoulder arthroplasty has limited durability and is not indicated in young patients with high functional demands. We developed a new technique for repairing massive rotator cuff tears by semitendinosus and gracilis myotendinous grafting. This novel therapeutic option allows massive rotator cuff tears to be repaired using autologous material that is adequate and adaptable, making it possible to cover any width of defect. The technique is low-invasive and not technically demanding, with minimal donor site morbidity. PMID:27900313

  8. 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

  9. The "Hoop" Plate for Posterior Bicondylar Shear Tibial Plateau Fractures: Description of a New Surgical Technique.

    PubMed

    Giordano, Vincenzo; Schatzker, Joseph; Kfuri, Mauricio

    2016-09-29

    High-energy fractures of the proximal tibia with extensive fragmentation of the posterior rim of the tibial plateau are challenging. This technique aims to describe a method on how to embrace the posterior rim of the tibial plateau by placing a horizontal precontoured one-third tubular plate wrapped around its corners. This method, which we named "hoop plating," is mainly indicated for cases of crushed juxta-articular rim fractures, aiming to restore cortical containment of the tibial plateau. Through a lateral approach with a fibular head osteotomy (Lobenhoffer approach), both anterolateral and posterolateral fragments are directly reduced and supported by a one-third tubular plate of adequate length. The plate is inserted from lateral to medial deep to all soft tissues, and its position is checked with fluoroscopy. The implant sits exactly on the posterior cortex of the tibial plateau and provides containment for the reduced juxta-articular posterior cortex and rim. We begin with immediate range of motion. Toe-touch weight-bearing with crutches is allowed with the operated knee in full extension. Weight-bearing is gradually increased only after 6 weeks as bone healing is taking place. Clinical follow-up is performed at 1, 3, 6, and 12 weeks. If the radiological exam confirms that the fracture is healed, the patient is allowed to proceed to muscle strengthening and bear weight entirely. The "hoop plating" may be a good option for the management in cases of extensive posterior tibial plateau articular surface fracture and impaction with rim and posterior cortical wall fragmentation.

  10. Dome osteotomy for posttraumatic cubitus varus: a surgical technique to avoid lateral condylar prominence.

    PubMed

    Pankaj, Amite; Dua, Aman; Malhotra, Rajesh; Bhan, Surya

    2006-01-01

    The indication for surgery in most children with posttraumatic cubitus varus is the presence of an unsightly deformity. The function of the limb is generally not impaired. Lateral closing-wedge supracondylar osteotomy, although a widely used corrective procedure, tends to produce lateral condylar prominence, thus jeopardizing the cosmetic outcome. The authors used the dome supracondylar osteotomy, as described by Tien et al, as the corrective procedure for cubitus varus in 12 consecutive children. The average follow-up was 2.3 (range 1-4) years. The objective evaluation was done by one of the authors by measuring the pre- and postoperative lateral condylar prominence index, carrying angle, and the range of movement at the elbow. The patients and parents were also asked to self-assess the cosmetic outcome. There were seven excellent and five good results. None of the children showed a prominent lateral humeral condyle. Hypertrophic scar formation and ulnar neurapraxia were seen in one patient each. These results were comparable to the published results of lateral closing-wedge osteotomy in terms of correction of carrying angle and preservation of elbow motion and were superior to those of the lateral closing-wedge osteotomy in terms of the prominence of lateral humeral condyle, acceptability of the scar, and cosmesis. The authors offer independent verification of the observation that the technique of dome osteotomy as described by Tien et al for the correction of the posttraumatic cubitus varus is a simple, safe, and technically sound procedure that prevents the lateral condyle from becoming prominent and yields an excellent cosmetic outcome.

  11. Surgical stabilization for open tibial fractures in children: External fixation or elastic stable intramedullary nail - which method is optimal?

    PubMed Central

    Ramasubbu, Rohan A; Ramasubbu, Benjamin M

    2016-01-01

    Background: Management of open tibial fractures is well documented in adults, with existing protocols outlining detailed treatment strategies. No clear guidelines exist for children. Surgical stabilization of tibial fractures in the pediatric population requires implants that do not disrupt the open epiphyses (growth plate). Both elastic stable intramedullary nails and external fixation can be used. The objective of this study was to identify the optimal method of surgical stabilization in the treatment of open tibial fractures in children. Materials and Methods: MEDLINE and Embase were searched from their inception to March 2014 using the following advanced search terms (Key words): “open tibia fracture,” “fracture fixation,” “external fixation,” “intramedullary,” and “bone nail.” Only studies in English and pertaining to children with open fractures treated with elastic stable intramedullary nails or external fixation between 1994 and 2014 were included. Twelve clinical studies were critically appraised. Results: Due to a paucity in the literature coupled with a nonsystematic presentation of results, it proved to be very difficult in extracting relevant results from the studies. This was further added by a variation in outcome measures. Consequently, the results we obtained were difficult to draw conclusions from. Conclusion: There is no conclusive evidence or best practice guidelines for their management. Thus, as is highlighted in this study, more research is needed to determine the optimum treatment strategy for this common pediatric injury. The existing literature is of poor quality; consisting mainly of retrospective reviews of patients’ medical records, charts, and radiographs. Carefully designed, high-quality prospective cohort studies utilizing a nationalized multi-hospital approach are needed to improve understanding before protocols and guidelines can be developed and implemented. PMID:27746486

  12. 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.

  13. 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

  14. Nonparametric probability density estimation by optimization theoretic techniques

    NASA Technical Reports Server (NTRS)

    Scott, D. W.

    1976-01-01

    Two nonparametric probability density estimators are considered. The first is the kernel estimator. The problem of choosing the kernel scaling factor based solely on a random sample is addressed. An interactive mode is discussed and an algorithm proposed to choose the scaling factor automatically. The second nonparametric probability estimate uses penalty function techniques with the maximum likelihood criterion. A discrete maximum penalized likelihood estimator is proposed and is shown to be consistent in the mean square error. A numerical implementation technique for the discrete solution is discussed and examples displayed. An extensive simulation study compares the integrated mean square error of the discrete and kernel estimators. The robustness of the discrete estimator is demonstrated graphically.

  15. Optimal Control Technique for Many-Body Quantum Dynamics

    NASA Astrophysics Data System (ADS)

    Doria, Patrick; Calarco, Tommaso; Montangero, Simone

    2011-05-01

    We present an efficient strategy for controlling a vast range of nonintegrable quantum many-body one-dimensional systems that can be merged with state-of-the-art tensor network simulation methods such as the density matrix renormalization group. To demonstrate its potential, we employ it to solve a major issue in current optical-lattice physics with ultracold atoms: we show how to reduce by about 2 orders of magnitude the time needed to bring a superfluid gas into a Mott insulator state, while suppressing defects by more than 1 order of magnitude as compared to current experiments [T. Stöferle , Phys. Rev. Lett. 92, 130403 (2004)PRLTAO0031-900710.1103/PhysRevLett.92.130403]. Finally, we show that the optimal pulse is robust against atom number fluctuations.

  16. Surgical Techniques to Increase the Apicocoronal Dimension of the Attached Gingiva: A 1-Year Comparison Between the Free Gingival Graft and the Modified Apically Repositioned Flap.

    PubMed

    Carnio, João; Camargo, Paulo M; Pirih, Paulo Q

    2015-01-01

    The attached gingiva is a desirable anatomical element for the maintenance of gingival health. The free gingival graft (FGG) and the modified apically repositioned flap (MARF) are predictable surgical techniques often employed to increase the zone of attached gingiva. This randomized study compared the FGG and the MARF in increasing the zone of attached gingiva in contralateral sides of 15 patients 1 year posttreatment. There was an increase in keratinized tissue and attached gingiva in both groups. Gingival recession did not significantly change between pre- and posttreatment levels in either group. The MARF surgical time was approximately half as long as that of the FGG. The authors conclude that both techniques are viable; however, the main advantages of the MARF were decreased surgical time and less postoperative discomfort.

  17. SYNTHESIZING OPTIMAL STRATEGIES IN PURSUIT-EVASION GAMES BY THE EPSILON TECHNIQUE,

    DTIC Science & Technology

    A constructive method for synthesizing optimal strategies in pursuit-evasion games is described using the epsilon technique as described by Balakrishnan. An illustrative example is worked out. (Author)

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Local versus global optimal sports techniques in a group of athletes.

    PubMed

    Huchez, Aurore; Haering, Diane; Holvoët, Patrice; Barbier, Franck; Begon, Mickael

    2015-01-01

    Various optimization algorithms have been used to achieve optimal control of sports movements. Nevertheless, no local or global optimization algorithm could be the most effective for solving all optimal control problems. This study aims at comparing local and global optimal solutions in a multistart gradient-based optimization by considering actual repetitive performances of a group of athletes performing a transition move on the uneven bars. Twenty-four trials by eight national-level female gymnasts were recorded using a motion capture system, and then multistart sequential quadratic programming optimizations were performed to obtain global optimal, local optimal and suboptimal solutions. The multistart approach combined with a gradient-based algorithm did not often find the local solution to be the best and proposed several other solutions including global optimal and suboptimal techniques. The qualitative change between actual and optimal techniques provided three directions for training: to increase hip flexion-abduction, to transfer leg and arm angular momentum to the trunk and to straighten hand path to the bar.

  3. Benign tumours affecting the deep lobe of the parotid gland: how to select the optimal surgical approach.

    PubMed

    Casani, A P; Cerchiai, N; Dallan, I; Seccia, V; Sellari Franceschini, S

    2015-04-01

    Many types of approaches allow extra-capsular dissection in the deep parotid parenchyma in the treatment of benign tumours. A transcervical approach (TCA), transparotid approach (TPA) and a combined transcervical-transparotid approach (TPTCA) are the three main procedures performed to expose the deep parenchyma. We conducted a retrospective chart review enrolling 24 consecutive patients treated for benign tumours affecting the deep lobe of the parotid. Review of the surgical data was accompanied by careful follow-up to establish surgical morbidity, functional (Frey's Syndrome and first-bite syndrome) and aesthetical outcomes. A TPA was performed in the majority of cases; in 26% superficial parotidectomy was not required (selective deep parotidectomy). Minor's test showed a low rate of Frey's syndrome (3 cases of 23, 13%). No long-lasting first-bite syndrome was reported. Some additional procedures were easily performed in order to improve aesthetical results (rotational flap of sternocleidomastoid muscle, free abdominal fat transfer); these had the same results as selective deep parotidectomy. TCA (or TPTCA) ensures the best control of the facial nerve, providing good exposure and good functional and aesthetical results (without sparing the superficial parenchyma if additional techniques are performed with the aim of reducing skin depression in the treated area). The choice of the approach should have only the aim of safe resection and should not be influenced by aesthetical outcome; the craniocaudal level of the tumour seems to be the best indicator of the feasibility of the procedure also considering the branches of the facial nerve. In our experience, mandibulotomy can always be avoided.

  4. 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

  5. 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].

  6. 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

  7. 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

  8. Surgical treatment of necrotic scleral calcification using combined conjunctival autografting and an amniotic membrane inlay filling technique

    PubMed Central

    Kim, B-H

    2011-01-01

    Purpose To introduce a novel technique to treat necrotic scleral calcification caused by previous regional conjunctivectomy using conjunctival autografting and amniotic membrane inlay filling, and to evaluate the clinical outcome. Methods Ten patients (11 eyes, 12 regions) who had undergone regional conjunctivectomy with postoperative mitomycin C (MMC) for pterygia or pingueculae were included. Scleral calcification was removed using a bevel-down crescent knife. After the conjunctival donor tissue was harvested from the upper bulbar conjunctiva, the tissue was grafted to the scleral defect and secured with sutures. Amniotic membrane was inserted randomly into spaces between the conjunctival graft and the scleral bed. Protective amniotic membrane was transplanted over the graft, with stromal side up. Results Scleral calcification developed in ischaemic areas in 11 of the 12 regions; 50% of cases had a surface defect seen with a fluorescent dye. The grafted conjunctiva epithelialized successfully in all cases. In 10 regions, the epithelialization occurred in 1 or 2 weeks. In the remaining two regions, one region required another surgery because of graft failure, and epithelialization occurred in the last region in 9 weeks. Vascular growth into the graft from the surrounding tissue occurred in all cases in 1 to 10 weeks. The surgical wound stabilized 3 weeks postoperatively. Conclusion The combined technique had high success rates of graft survival and good revitalization of the necrotic area of scleral calcification, eliminated the need for invasive and time-consuming scleral autografting or allografting, and provided good cosmesis. Scleral ischaemia, which was caused by MMC, may induce scleral calcification. PMID:21869832

  9. Optimization and validation of an existing, surgical and robust dry eye rat model for the evaluation of therapeutic compounds.

    PubMed

    Joossen, Cedric; Lanckacker, Ellen; Zakaria, Nadia; Koppen, Carina; Joossens, Jurgen; Cools, Nathalie; De Meester, Ingrid; Lambeir, Anne-Marie; Delputte, Peter; Maes, Louis; Cos, Paul

    2016-05-01

    The aim of this research was to optimize and validate an animal model for dry eye, adopting clinically relevant evaluation parameters. Dry eye was induced in female Wistar rats by surgical removal of the exorbital lacrimal gland. The clinical manifestations of dry eye were evaluated by tear volume measurements, corneal fluorescein staining, cytokine measurements in tear fluid, MMP-9 mRNA expression and CD3(+) cell infiltration in the conjunctiva. The animal model was validated by treatment with Restasis(®) (4 weeks) and commercial dexamethasone eye drops (2 weeks). Removal of the exorbital lacrimal gland resulted in 50% decrease in tear volume and a gradual increase in corneal fluorescein staining. Elevated levels of TNF-α and IL-1α have been registered in tear fluid together with an increase in CD3(+) cells in the palpebral conjunctiva when compared to control animals. Additionally, an increase in MMP-9 mRNA expression was recorded in conjunctival tissue. Reference treatment with Restasis(®) and dexamethasone eye drops had a positive effect on all evaluation parameters, except on tear volume. This rat dry eye model was validated extensively and judged appropriate for the evaluation of novel compounds and therapeutic preparations for dry eye disease.

  10. 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

  11. 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

  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. Optimizing Sudden Passage in the Earth's-Field NMR Technique

    NASA Astrophysics Data System (ADS)

    Melton, B. F.; Pollak, V. L.

    The equation of motion dM/ dt= γM × B( t) is solved numerically for the case B( t) = j Bp( t) + k Be. The field Beis a small static field, typically the earth's field. The field Bp( t) is a damped oscillation having frequency greater than, or on the order of, the precession frequency in field Be. Such oscillation inevitably occurs at the end of the rapid cutoff of the coil current used to polarize the sample. It is assumed that Bp( t) is initially large compared to Be, and that magnetization M is initially along the resultant field B. This is the usual situation in the earth's-field NMR technique when the polarizing field is produced by a coil of moderate to high impedance. It is shown that, when properly damped, the transient can be used to restore the magnetization to the x-yplane, thereby maximizing the amplitude of the subsequent free precession signal. The damping required is close to critical damping, so that the problem of circuit ringing when the coil is switched to receiver mode is also eliminated.

  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. Chemical complexity in astrophysical simulations: optimization and reduction techniques

    NASA Astrophysics Data System (ADS)

    Grassi, T.; Bovino, S.; Schleicher, D.; Gianturco, F. A.

    2013-05-01

    Chemistry plays a key role in the evolution of the interstellar medium, so it is highly important to follow its evolution in numerical simulations. However, it could easily dominate the computational cost when applied to large systems. In this paper we discuss two approaches to reduce these costs: (i) based on computational strategies, and (ii) based on the properties and on the topology of the chemical network. The first methods are more robust, while the second are meant to be giving important information on the structure of large, complex networks. We first discuss the numerical solvers for integrating the system of ordinary differential equations (ODE) associated with the chemical network, and then we propose a buffer method that decreases the computational time spent in solving the ODE system. We further discuss a flux-based method that allows one to determine and then cut on the fly the less active reactions. In addition we also present a topological approach for selecting the most probable species that will be active during the chemical evolution, thus gaining information on the chemical network that otherwise would be difficult to retrieve. This topological technique can also be used as an a priori reduction method for any size network. We implemented these methods into a 1D Lagrangian hydrodynamical code to test their effects: both classes lead to large computational speed-ups, ranging from ×2 to ×5. We have also tested some hybrid approaches finding that coupling the flux method with a buffer strategy gives the best trade-off between robustness and speed-up of calculations.

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

    PubMed

    Wesseling, Mariska; Derikx, Loes C; de Groote, Friedl; Bartels, Ward; Meyer, Christophe; Verdonschot, Nico; Jonkers, Ilse

    2015-03-01

    In musculoskeletal modelling, several optimization techniques are used to calculate muscle forces, which strongly influence resultant hip contact forces (HCF). The goal of this study was to calculate muscle forces using four different optimization techniques, i.e., two different static optimization techniques, computed muscle control (CMC) and the physiological inverse approach (PIA). We investigated their subsequent effects on HCFs during gait and sit to stand and found that at the first peak in gait at 15-20% of the gait cycle, CMC calculated the highest HCFs (median 3.9 times peak GRF (pGRF)). When comparing calculated HCFs to experimental HCFs reported in literature, the former were up to 238% larger. Both static optimization techniques produced lower HCFs (median 3.0 and 3.1 pGRF), while PIA included muscle dynamics without an excessive increase in HCF (median 3.2 pGRF). The increased HCFs in CMC were potentially caused by higher muscle forces resulting from co-contraction of agonists and antagonists around the hip. Alternatively, these higher HCFs may be caused by the slightly poorer tracking of the net joint moment by the muscle moments calculated by CMC. We conclude that the use of different optimization techniques affects calculated HCFs, and static optimization approached experimental values best.

  18. Gradient vs. approximation design optimization techniques in low-dimensional convex problems

    NASA Astrophysics Data System (ADS)

    Fedorik, Filip

    2013-10-01

    Design Optimization methods' application in structural designing represents a suitable manner for efficient designs of practical problems. The optimization techniques' implementation into multi-physical softwares permits designers to utilize them in a wide range of engineering problems. These methods are usually based on modified mathematical programming techniques and/or their combinations to improve universality and robustness for various human and technical problems. The presented paper deals with the analysis of optimization methods and tools within the frame of one to three-dimensional strictly convex optimization problems, which represent a component of the Design Optimization module in the Ansys program. The First Order method, based on combination of steepest descent and conjugate gradient method, and Supbproblem Approximation method, which uses approximation of dependent variables' functions, accompanying with facilitation of Random, Sweep, Factorial and Gradient Tools, are analyzed, where in different characteristics of the methods are observed.

  19. An Artificial Intelligence Technique to Generate Self-Optimizing Experimental Designs.

    DTIC Science & Technology

    1983-02-01

    pattern or a binary chopping technique in the space of decision variables while carrying out a sequence of contiroLled experiments on the strategy ...7 AD-A127 764 AN ARTIFICIAL INTELLIGENCE TECHNIQUE TO GENERATE 1/1 SELF-OPTIMIZING EXPERIME. .(U) ARIZONA STATE UNIV TEMPE GROUP FOR COMPUTER STUDIES...6 3 A - - II 1* Ii.LI~1 11. AI-. jMR.TR- 3 0 3 37 AN ARTIFICIAL INTELLIGENCE TECHNIQUE TO GENERATE SELF-OPTIMIZING EXPERIMENTAL DESIGNS Nicholas V

  20. Use of an infrared temperature monitoring system to determine optimal temperature for arterial repair using light-activated surgical adhesive

    NASA Astrophysics Data System (ADS)

    Soller, Eric C.; Hoffman, Grant T.; McNally-Heintzelman, Karen M.

    2003-06-01

    The ability to reproduce strong repairs is essential to establishing the reliability of laser-tissue soldering techniques and advancing their use to the clinical setting. While some thermal damage is necessary to achieve a viable solder-tissue bond, excessive thermal damage leads to decreased flexibility and strength of the repair. In addition, if the temperature at the solder/tissue interface is too low, inadequate solder-tissue bonding will occur to provide a strong repair. This suggests the presence of an optimal temperature for laser-tissue repair. The choice of solder material presents another challenge to the reproducibility of strong repairs. The emerging use of chromophore-enhanced solder-doped polymer scaffolds offers numerous advantages over more traditional liquid and solid solders composed of serum albumin and an absorbing chromophore mixed in deionized water. Polymer scaffolds, fabricated from poly(L-lactic-co-glycolic acid) using a solvent casting and particulate leaching technique, are porous enough to absorb serum albumin and can also be doped with various hemostatic and thrombogenic agents to aid in tissue healing. Use of the polymer scaffolds allows one to combine the strength of solid solders and the flexibility of liquid solders without the common "runaway" problems. An in vitro study was performed to correlate tissue temperature with the tensile strength of arterial repairs formed using the chromophore-enhanced solder-doped polymer scaffolds. Laser irradiance was varied and the solder surface and solder/tissue interface temperatures were monitored by an IR temperature monitoring system and a type-K thermocouple, respectively. The solder/tissue interface temperature required for optimized tensile strength was determined to be 67 +/- 5°C. This value was in agreement with previous studies using serum albumin solders alone, where the optimal solder/tissue interface temperature was found to be 65°C.

  1. Resection Margin and Survival in 2368 Patients Undergoing Hepatic Resection for Metastatic Colorectal Cancer: Surgical Technique or Biologic Surrogate?

    PubMed Central

    Sadot, Eran; Koerkamp, Bas Groot; Leal, Julie N.; Shia, Jinru; Gonen, Mithat; Allen, Peter J.; DeMatteo, Ronald P.; Kingham, T. Peter; Kemeny, Nancy; Blumgart, Leslie H.; Jarnagin, William R.; D’Angelica, Michael I.

    2015-01-01

    OBJECTIVE The impact of margin width on overall survival (OS) in the context of other prognostic factors after resection for colorectal liver metastases (CRLM) is unclear. We evaluated the relationship between resection margin and OS utilizing high-resolution histologic distance measurements. METHODS A single institution prospectively maintained database was queried for all patients who underwent an initial complete resection of CRLM between 1992–2012. R1 resection was defined as tumor cells at the resection margin (0 mm). R0 resection was further divided into 3 groups: 0.1–0.9 mm, 1–9 mm, ≥ 10mm. RESULTS A total of 4915 liver resections were performed at MSKCC between 1992 and 2012, from which 2368 patients were included in the current study. Half of the patients presented with synchronous disease, 43% had solitary metastasis, and the median tumor size was 3.4cm. With a median follow-up for survivors of 55 months, the median OS of the R1, 0.1–0.9 mm, 1–9 mm, and ≥ 10mm groups were 32, 40, 53, and 56 months, respectively (p < 0.001). Compared to R1 resection, all margin widths, including submillimeter margins correlated with prolonged OS (p < 0.05). The association between the margin width and OS remained significant when adjusted for all other clinicopathologic prognostic factors. CONCLUSIONS Resection margin width is independently associated with OS. Wide margins should be attempted whenever possible. However, resection should not be precluded if narrow margins are anticipated, as submillimeter margin clearance is associated with improved survival. The prolonged OS observed with submillimeter margins is likely a microscopic surrogate for the biologic behavior of a tumor rather than the result of surgical technique. PMID:26258316

  2. A minimally invasive surgical technique for augmented reconstruction of the lateral ankle ligaments with woven polyester tape.

    PubMed

    Jones, Alex P; Sidhom, Sameh; Sefton, Graham

    2007-01-01

    Although stabilization of the lateral ankle ligament complex (LALC) with augmented techniques is known to be successful, it is associated with a number of complications. We hypothesize that successful stabilization of LALC can be achieved with a woven polyester tape implant via a minimally invasive procedure, as an alternative to tenodesis. Four men with chronic instability of the ankle underwent a minimally invasive surgical stabilization of LALC with a woven polyester tape. This tape was passed through the distal fibula to the base of the fifth metatarsal and then back to the fibula once more before being tied. The foot was immobilized in a neutral position for 2 weeks. Partial weightbearing with a walking stick began on the same day, and physiotherapy began for 10 weeks. Evaluation was performed at a mean follow-up of 24.5 months postoperatively. Preoperatively, all patients had a chronically unstable index ankle both functionally and clinically. At a mean of 24.5 months postoperatively, functional stability for all patients was normal (Sefton grade 1). Subjective ankle performance grades were normal in all cases, and all patients felt the outcome was excellent. Objective measurement with clinical stress testing showed anterior drawer and inversion tests to be the same as the contralateral ankle in all patients. However, each displayed limited inversion of the ankle. No complications such as wound dehiscence, infection, pain, or nerve injury were observed after the procedure. All were able to return to their preinjury activity level within 3 months. Stabilization of LALC may be simply and successfully achieved with a woven polyester graft as an alternative to tenodesis.

  3. 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.

  4. 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.

  5. A technique for optimizing electrode placement for electromyographic control of prostheses.

    PubMed

    Walbran, Scott H; Calius, Emilio P; Dunlop, G; Anderson, Iain A

    2009-01-01

    We present a technique that enables optimization of Electromyographic (EMG) electrode placement for grasp recognition. Previous works have shown that sophisticated control techniques for prosthetic devices are becoming available; however the issue of electrode placement has yet to be addressed. By processing a rich field of data, it is possible to determine which of the data sets will allow for greatest accuracy in prosthetic control. Data has been collected and processed from 128 sites on a human forearm while two different grasps were performed. Using two different feature extraction techniques - integral of absolute value and differential absolute value - the difference in means between performing each grasp type has been analyzed. This resulted in several regions around the wrist and the elbow that would be optimal for this particular setup. While the optimization process has been used here for discrimination between two particular grasps, it has the potential to extend to any desired actuation pattern.

  6. Comparison of surgical conditions in 2 different anesthesia techniques of esmolol-induced controlled hypotension in breast reduction surgery

    PubMed Central

    Besir, Ahmet; Cekic, Bahanur; Kutanis, Dilek; Akdogan, Ali; Livaoglu, Murat

    2017-01-01

    Abstract Background: Breast reduction surgery is a common cosmetic surgery with a high incidence of blood loss and transfusion. In this surgery, the reduction of blood loss related to surgical manipulation and the volume of resected tissue is a target. In the present study, we compared the effects of esmolol-induced controlled hypotension on surgical visibility, surgical bleeding, and the duration of surgery in patients anesthetized with propofol/remifentanil (PR) or sevoflurane/remifentanil (SR). Methods: Patients in the American Society of Anesthesiologists I/II risk group undergoing breast reduction surgery were prospectively randomized into PR (n = 25) and SR (n = 25) groups. Controlled hypotension was induced with esmolol in both groups. During the intraoperative period, the heart rate (HR), mean arterial pressure (MAP), operation duration, volume of intraoperative blood loss, volume of blood received through postoperative drains, volume of resected tissues, and surgical area bleeding score were recorded. Results: The duration of operation in the incisional period was shorter in group PR compared to group SR (P = 0.04). The change in HR was lower in incision and hemostasis periods in the group PR compared to the group SR (P < 0.001). Total intraoperative intraoperative bleeding volume and volume of blood received through drains on postoperative postoperative day 1, day 2, and in total were found to be significantly lower in group PR compared to group SR. Surgical visibility scoring was more effective in group PR compared to SR. Conclusion: In the breast reduction surgery performed under esmolol-induced controlled hypotension, the effect of propofol + remifentanil anesthesia on the duration of incisional surgery, surgical visibility, and volume of surgical blood loss was more reliable and effective compared to that of sevoflurane + remifentanil, which seems to be an advantage. PMID:28272228

  7. Surgical innovation as sui generis surgical research.

    PubMed

    Lotz, Mianna

    2013-12-01

    Successful innovative 'leaps' in surgical technique have the potential to contribute exponentially to surgical advancement, and thereby to improved health outcomes for patients. Such innovative leaps often occur relatively spontaneously, without substantial forethought, planning, or preparation. This feature of surgical innovation raises special challenges for ensuring sufficient evaluation and regulatory oversight of new interventions that have not been the subject of controlled investigatory exploration and review. It is this feature in particular that makes early-stage surgical innovation especially resistant to classification as 'research', with all of the attendant methodological and ethical obligations--of planning, regulation, monitoring, reporting, and publication--associated with such a classification. This paper proposes conceptual and ethical grounds for a restricted definition according to which innovation in surgical technique is classified as a form of sui generis surgical 'research', where the explicit goal of adopting such a definition is to bring about needed improvements in knowledge transfer and thereby benefit current and future patients.

  8. Primary pulmonary artery sarcoma: a new surgical technique for pulmonary artery reconstruction using a self-made stapled bovine pericardial graft conduit.

    PubMed

    Obeso Carillo, Gerardo Andrés; Casais Pampín, Rocío; Legarra Calderón, Juan José; Pradas Montilla, Gonzalo

    2015-01-01

    Primary pulmonary artery sarcoma is an uncommon neoplasm with a grim prognosis. Complete resection is the only treatment that can improve the patient's survival. The role of multimodality treatment is still controversial, although adjuvant chemotherapy possibly could improve outcomes of these patients. Several pulmonary artery reconstructive techniques have been reported in the scientific literature, such as patch reconstruction, end-to-end anastomosis, synthetic prosthesis or biological grafts. In this article, we propose a new surgical option for pulmonary artery reconstruction after radical tumour resection using a self-made stapled bovine pericardial graft conduit in a patient with a mass in the pulmonary trunk and right pulmonary artery. We believe that the use of this technique adds safety and effectiveness, and reduces the surgical time.

  9. Rapid orthodontic treatment after the ridge-splitting technique--a combined surgical-orthodontic approach for implant site development: case report.

    PubMed

    Amato, Francesco; Mirabella, A Davide; Borlizzi, Diego

    2012-08-01

    This article presents a clinical case of bilateral partial edentulism in the posterior mandible with severe horizontal and moderate vertical bone atrophy. A new technique using rapid orthodontics after ridge splitting is presented. The split-crest technique was carried out using piezosurgical instruments in the first molar and second premolar areas to widen the bone crest and open a channel for tooth movement. Immediately after, orthodontic appliances were used to move the first premolars distally and the second molars mesially into the surgical site. The rationale was to facilitate and accelerate orthodontic movement of the teeth, which is otherwise difficult in a cortical knife-edged ridge. The bone defect was filled with the alveolar bone of the adjacent teeth that were moved into the surgically opened path. Adequate bone volume for implant placement was generated in the first premolar area. Implants were then inserted, and the patient was rehabilitated.

  10. Optimization technique of wavefront coding system based on ZEMAX externally compiled programs

    NASA Astrophysics Data System (ADS)

    Han, Libo; Dong, Liquan; Liu, Ming; Zhao, Yuejin; Liu, Xiaohua

    2016-10-01

    Wavefront coding technique as a means of athermalization applied to infrared imaging system, the design of phase plate is the key to system performance. This paper apply the externally compiled programs of ZEMAX to the optimization of phase mask in the normal optical design process, namely defining the evaluation function of wavefront coding system based on the consistency of modulation transfer function (MTF) and improving the speed of optimization by means of the introduction of the mathematical software. User write an external program which computes the evaluation function on account of the powerful computing feature of the mathematical software in order to find the optimal parameters of phase mask, and accelerate convergence through generic algorithm (GA), then use dynamic data exchange (DDE) interface between ZEMAX and mathematical software to realize high-speed data exchanging. The optimization of the rotational symmetric phase mask and the cubic phase mask have been completed by this method, the depth of focus increases nearly 3 times by inserting the rotational symmetric phase mask, while the other system with cubic phase mask can be increased to 10 times, the consistency of MTF decrease obviously, the maximum operating temperature of optimized system range between -40°-60°. Results show that this optimization method can be more convenient to define some unconventional optimization goals and fleetly to optimize optical system with special properties due to its externally compiled function and DDE, there will be greater significance for the optimization of unconventional optical system.

  11. 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.

  12. Treatment modalities for surgical management of anterior palatal fistula: Comparison of various techniques, their outcomes, and the factors governing treatment plan: A retrospective study

    PubMed Central

    Bonanthaya, Krishnamurthy; Shetty, Pritham; Sharma, Abhimanyu; Ahlawat, Jyoti; Passi, Deepak; Singh, Mahinder

    2016-01-01

    Aim: Aim of this retrospective study was to access the various surgical treatment options available for repair of Anterior palatal fistula depending upon their size and presenting age, and also to anticipate the treatment outcome. Materials and Methods: The series include study report of forty patients with secondary anterior palatal fistula post cleft palate repair, reported in a single unit during a duration of 3 years. All the cases were managed surgically under general anesthesia. The patients were classified depending upon the location of anterior palatal fistula (APF), the quality of tissue and age of patients to chalk out a justified treatment option outlay. Results: Forty cases were split for surgical correction into various options depending on their size, site, and quality of the tissue. Most of the cases were operated with a Bardach's Redo for fistula closure (n = 16) (40%) and crevicular flap technique (n = 13) (32.5%). Our overall success (satisfactory results) was 77.5% as observed in 31 out of 40 cases with individual success rates for Bardach's and crevicular being 75% and 77%, respectively. There was reduction in size of fistula in three cases (7.5%) and a remnant pinpoint hole in four cases (10%) among all the operated cases. Conclusion: Management of post palatoplasty fistulas of the hard palate presents a challenging situation for a clinician following the surgical correction of cleft palate. Current paper describes the diagnosis and clinical management of forty cases reporting with unilateral APF following cleft palate surgery, over 3 years. Authors have attempted to propose different treatment modalities for surgical management of unilateral APF. It was concluded in the primary review that the size of fistula was irrelevant in determining the clinical outcome. Instead, the quality and condition of the adjacent tissue appear to be the major governing factors for selecting treatment modality as well as the surgical consequences. PMID:28356685

  13. A review of ligament augmentation with the InternalBrace™: the surgical principle is described for the lateral ankle ligament and ACL repair in particular, and a comprehensive review of other surgical applications and techniques is presented.

    PubMed

    Mackay, Gordon M; Blyth, Mark J G; Anthony, Iain; Hopper, Graeme P; Ribbans, William J

    2015-05-01

    This article reviews the surgical decision-making considerations when preparing to undertake an anatomic ligament repair with augmentation using the InternalBrace™. Lateral ankle ligament stabilization of the Broström variety and ACL repair in particular are used to illustrate its application. The InternalBrace™ supports early mobilization of the repaired ligament and allows the natural tissues to progressively strengthen. The principle established by this experience has resulted in its successful application to other distal extremity ligaments including the deltoid, spring, and syndesmosis complex. Knee ligament augmentation with the InternalBrace™ has been successfully applied to all knee ligaments including anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), lateral collateral ligament (LCL), anterolateral ligament (ALL), and patellofemoral ligament (PFL). The surgical technique and early results will be reviewed including multi-ligament presentations. Upper limb experience with acromioclavicular (AC) joint augmentation and ulnar collateral ligament (UCL) repair of the elbow with the InternalBrace™ will also be discussed. This article points to a change in orthopaedic practice positioning reconstruction as a salvage procedure that has additional surgical morbidity and should be indicated only if the tissues fail to heal adequately after augmentation and repair.

  14. 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. ...

  15. Do Clinical Results and Return-to-Sport Rates After Ulnar Collateral Ligament Reconstruction Differ Based on Graft Choice and Surgical Technique?

    PubMed Central

    Erickson, Brandon J.; Cvetanovich, Gregory L.; Frank, Rachel M.; Bach, Bernard R.; Cohen, Mark S.; Bush-Joseph, Charles A.; Cole, Brian J.; Romeo, Anthony A.

    2016-01-01

    Background: Ulnar collateral ligament reconstruction (UCLR) has become a common procedure performed in overhead-throwing athletes of many athletic levels. Purpose/Hypothesis: The purpose of this study was to determine whether clinical outcomes and return-to-sport (RTS) rates differ among patients undergoing UCLR based on graft choice, surgical technique, athletic competition level, handedness, and treatment of the ulnar nerve. We hypothesized that no differences would exist in clinical outcomes or RTS rates between technique, graft choice, or other variables. Study Design: Cohort study; Level of evidence, 3. Methods: All patients who underwent UCLR from January 1, 2004 through December 31, 2014 at a single institution were identified. Charts were reviewed to determine patient age, sex, date of surgery, sport played, handedness, athletic level, surgical technique, graft type, and complications. Patients were contacted via telephone to obtain the RTS rate, Conway-Jobe score, Timmerman-Andrews score, and Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow score. Results: Eighty-five patients (mean age at surgery, 19.3 ± 4.7 years; 92% male; 78% right hand–dominant) underwent UCLR between 2004 and 2014 and were available for follow-up. Overall, 87% were baseball pitchers, 49.4% were college athletes, and 41.2% were high school athletes. No significant difference existed between the docking and double-docking techniques, graft choice, handedness, sex, activity level, and treatment of the ulnar nerve with regard to clinical outcomes, RTS, or subsequent surgeries (all P > .05). More complications were seen in the docking technique compared with the double-docking technique (P = .036). Hamstring autograft was used more commonly with the docking technique (P = .023) while allograft was used more commonly with the double-docking technique (P = .0006). Conclusion: Both the docking and double-docking techniques produce excellent clinical outcomes in patients undergoing

  16. [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.

  17. Application of Genetic Algorithm and Particle Swarm Optimization techniques for improved image steganography systems

    NASA Astrophysics Data System (ADS)

    Jude Hemanth, Duraisamy; Umamaheswari, Subramaniyan; Popescu, Daniela Elena; Naaji, Antoanela

    2016-01-01

    Image steganography is one of the ever growing computational approaches which has found its application in many fields. The frequency domain techniques are highly preferred for image steganography applications. However, there are significant drawbacks associated with these techniques. In transform based approaches, the secret data is embedded in random manner in the transform coefficients of the cover image. These transform coefficients may not be optimal in terms of the stego image quality and embedding capacity. In this work, the application of Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) have been explored in the context of determining the optimal coefficients in these transforms. Frequency domain transforms such as Bandelet Transform (BT) and Finite Ridgelet Transform (FRIT) are used in combination with GA and PSO to improve the efficiency of the image steganography system.

  18. A multi-agent technique for contingency constrained optimal power flows

    SciTech Connect

    Talukdar, S.; Ramesh, V.C. . Engineering Design Research Center)

    1994-05-01

    This paper does three things. First, it proposes that each critical contingency in a power system be represented by a correction time'' (the time required to eliminate the violations produced by the contingency), rather than by a set of hard constraints. Second, it adds these correction times to an optimal power flow and decomposes the resulting problem into a number of smaller optimization problems. Third, it proposes a multiagent technique for solving the smaller problems in parallel. The agents encapsulate traditional optimization algorithms as well as a new algorithm, called the voyager, that generates starting points for the traditional algorithms. All the agents communicate asynchronously, meaning that they can work in parallel without ever interrupting or delaying one another. The resulting scheme has potential for handling power system contingencies and other difficult global optimization problems.

  19. 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.

  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. Stab wound to the intramedullary spinal cord: Presurgical and surgical management options for a retained blade to optimize neurological preservation

    PubMed Central

    Agarwal, Prateek; Burke, John F.; Abdullah, Kalil G.; Piazza, Matthew; Smith, Brian P.; Thawani, Jayesh P.; Malhotra, Neil R.

    2016-01-01

    Background: We present a rare case of an intraparenchymal nonmissile penetrating spinal injury (NMPSI) occurring at the T11 level in a patient presenting without neurological deficit. Case Description: The patient sustained a knife wound that penetrated the lamina without incurring bony injury and entered the spinal cord at the T11 level. During surgery, the intramedullary penetration of the cord was confirmed, and following surgical removal of the knife, the patient fully recovered without losing any neurological function. Conclusions: The surgical management of NMPSI in patients who are neurologically intact is controversial. Here, we report surgical excision of a knife that penetrated the spinal cord at the T11 level, without the patient incurring further neurological deterioration. PMID:28144493

  2. 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

  3. [Main indicators of educational activity at the Department of Operative Techniques and Surgical Research at the University of Debrecen between 2000-2013].

    PubMed

    Pető, Katalin; Németh, Norbert; Lesznyák, Tamás; Furka, István; Mikó, Irén

    2013-06-01

    The authors provide a review about the main parameters of the gradual and postgradual educational activity of the Department of Operative Techniques and Surgical Research between 2000-2013. In this period of time several new subjects and courses have been introduced. The thematics have been widened, and the educational topics underwent a significant change and development: new teaching videos, revised note-books and a new textbook have been prepared through these years. Further, new training models (surgical training models, phantom and biomodels) have also been evolved. The educational activity of the Department was supported significantly several times (financial, contribution, grants) from the University of Debrecen, partner companies, HEFOP and TÁMOP grants. Infrastructural development in conjunction with the above increased the quality of educational standards in gradual and postgradual education, too. All these changes and developments were presented on various professional meetings and published in relevant journals, as part ofinternal quality control.

  4. Application of heuristic optimization techniques and algorithm tuning to multilayered sorptive barrier design.

    PubMed

    Matott, L Shawn; Bartelt-Hunt, Shannon L; Rabideau, Alan J; Fowler, K R

    2006-10-15

    Although heuristic optimization techniques are increasingly applied in environmental engineering applications, algorithm selection and configuration are often approached in an ad hoc fashion. In this study, the design of a multilayer sorptive barrier system served as a benchmark problem for evaluating several algorithm-tuning procedures, as applied to three global optimization techniques (genetic algorithms, simulated annealing, and particle swarm optimization). Each design problem was configured as a combinatorial optimization in which sorptive materials were selected for inclusion in a landfill liner to minimize the transport of three common organic contaminants. Relative to multilayer sorptive barrier design, study results indicate (i) the binary-coded genetic algorithm is highly efficient and requires minimal tuning, (ii) constraint violations must be carefully integrated to avoid poor algorithm convergence, and (iii) search algorithm performance is strongly influenced by the physical-chemical properties of the organic contaminants of concern. More generally, the results suggest that formal algorithm tuning, which has not been widely applied to environmental engineering optimization, can significantly improve algorithm performance and provide insight into the physical processes that control environmental systems.

  5. Optimized Axillary Vein Technique versus Subclavian Vein Technique in Cardiovascular Implantable Electronic Device Implantation: A Randomized Controlled Study

    PubMed Central

    Liu, Peng; Zhou, Yi-Feng; Yang, Peng; Gao, Yan-Sha; Zhao, Gui-Ru; Ren, Shi-Yan; Li, Xian-Lun

    2016-01-01

    Background: The conventional venous access for cardiovascular implantable electronic device (CIED) is the subclavian vein, which is often accompanied by high complication rate. The aim of this study was to assess the efficacy and safety of optimized axillary vein technique. Methods: A total of 247 patients undergoing CIED implantation were included and assigned to the axillary vein group or the subclavian vein group randomly. Success rate of puncture and complications in the perioperative period and follow-ups were recorded. Results: The overall success rate (95.7% vs. 96.0%) and one-time success rate (68.4% vs. 66.1%) of punctures were similar between the two groups. In the subclavian vein group, pneumothorax occurred in three patients. The subclavian gaps of three patients were too tight to allow operation of the electrode lead. In contrast, there were no puncture-associated complications in the axillary vein group. In the patient follow-ups, two patients in the subclavian vein group had subclavian crush syndrome and both of them received lead replacement. The incidence of complications during the perioperative period and follow-ups of the axillary vein group and the subclavian vein group was 1.6% (2/125) and 8.2% (10/122), respectively (χ2 = 5.813, P = 0.016). Conclusion: Optimized axillary vein technique may be superior to the conventional subclavian vein technique for CIED lead placement. Trial Registration: www.clinicaltrials.gov, NCT02358551; https://clinicaltrials.gov/ct2/show/NCT02358551?term=NCT02358551& rank=1. PMID:27823994

  6. Sequential design of linear quadratic state regulators via the optimal root-locus techniques

    NASA Technical Reports Server (NTRS)

    Shieh, L. S.; Dib, H. M.; Yates, R. E.

    1988-01-01

    The use of well-known root-locus techniques for sequentially finding the weighting matrices and the linear quadratic state regulators of multivariable control systems in the frequency domain is considered. This sequential design method permits the retention of some stable open-loop poles and the associated eigenvectors in the closed-loop system; it also allows some optimal closed-loop poles to be placed in a specific region of the complex plane. In addition, it provides a design procedure for determining the weighting matrices and linear quadratic state regulators for the optimal control of multivariable systems in the frequency domain.

  7. A study of optimization techniques in HDR brachytherapy for the prostate

    NASA Astrophysics Data System (ADS)

    Pokharel, Ghana Shyam

    . Based on our study, DVH based objective function performed better than traditional variance based objective function in creating a clinically acceptable plan when executed under identical conditions. Thirdly, we studied the multiobjective optimization strategy using both DVH and variance based objective functions. The optimization strategy was to create several Pareto optimal solutions by scanning the clinically relevant part of the Pareto front. This strategy was adopted to decouple optimization from decision such that user could select final solution from the pool of alternative solutions based on his/her clinical goals. The overall quality of treatment plan improved using this approach compared to traditional class solution approach. In fact, the final optimized plan selected using decision engine with DVH based objective was comparable to typical clinical plan created by an experienced physicist. Next, we studied the hybrid technique comprising both stochastic and deterministic algorithm to optimize both dwell positions and dwell times. The simulated annealing algorithm was used to find optimal catheter distribution and the DVH based algorithm was used to optimize 3D dose distribution for given catheter distribution. This unique treatment planning and optimization tool was capable of producing clinically acceptable highly reproducible treatment plans in clinically reasonable time. As this algorithm was able to create clinically acceptable plans within clinically reasonable time automatically, it is really appealing for real time procedures. Next, we studied the feasibility of multiobjective optimization using evolutionary algorithm for real time HDR brachytherapy for the prostate. The algorithm with properly tuned algorithm specific parameters was able to create clinically acceptable plans within clinically reasonable time. However, the algorithm was let to run just for limited number of generations not considered optimal, in general, for such algorithms. This was

  8. Comparison of two spatial optimization techniques: a framework to solve multiobjective land use distribution problems.

    PubMed

    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.

  9. 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.

  10. 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

  11. Laser induced deflection technique for absolute thin film absorption measurement: optimized concepts and experimental results

    SciTech Connect

    Muehlig, Christian; Kufert, Siegfried; Bublitz, Simon; Speck, Uwe

    2011-03-20

    Using experimental results and numerical simulations, two measuring concepts of the laser induced deflection (LID) technique are introduced and optimized for absolute thin film absorption measurements from deep ultraviolet to IR wavelengths. For transparent optical coatings, a particular probe beam deflection direction allows the absorption measurement with virtually no influence of the substrate absorption, yielding improved accuracy compared to the common techniques of separating bulk and coating absorption. For high-reflection coatings, where substrate absorption contributions are negligible, a different probe beam deflection is chosen to achieve a better signal-to-noise ratio. Various experimental results for the two different measurement concepts are presented.

  12. 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

  13. A nonlinear interval number programming method based on RBF global optimization technique

    NASA Astrophysics Data System (ADS)

    Zhao, Ziheng; Han, Xu; Chao, Jiang

    2010-05-01

    In this paper, a new nonlinear interval-based programming (NIP) method based on Radial basis function (RBF) approximation models and RBF global search technique method is proposed. In NIP, searching for the extreme responses of objective and constraints are integrated with the main optimization, which leads to extremely low efficiency. Approximation models are commonly used to promote the computational efficiency. Consequently, two inevitable problems are encountered. The first one is how to obtain the global minimum and maximum in the sub-optimizations. The second one is how to diminish the approximation errors on the response bounds of system. The present method combined with RBF global search technique shows a good feature to overcome these problems. High accuracy and low computational cost can be achieved simultaneously. Two numerical examples are used to test the effectiveness of the present method.

  14. 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.

  15. Chemometric experimental design based optimization techniques in capillary electrophoresis: a critical review of modern applications.

    PubMed

    Hanrahan, Grady; Montes, Ruthy; Gomez, Frank A

    2008-01-01

    A critical review of recent developments in the use of chemometric experimental design based optimization techniques in capillary electrophoresis applications is presented. Current advances have led to enhanced separation capabilities of a wide range of analytes in such areas as biological, environmental, food technology, pharmaceutical, and medical analysis. Significant developments in design, detection methodology and applications from the last 5 years (2002-2007) are reported. Furthermore, future perspectives in the use of chemometric methodology in capillary electrophoresis are considered.

  16. Optimization techniques for FORTRAN 4 (G and H) programs written for the IBM 360 under OS

    NASA Technical Reports Server (NTRS)

    Dean, J. L.

    1971-01-01

    A fairly complete list is reported of programming techniques which are available to the programmer for optimizing the execution time of production programs written in FORTRAN IV (G and H) for the IBM 360 under OS. After the program has been complied under FORTRAN H, OPT=2, then the process of actually changing code begins. The bulk of execution time of FORTRAN programs can almost always be attributed to a few loops, and primary consideration is given to these.

  17. 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.

  18. Application of non-linear automatic optimization techniques for calibration of HSPF.

    PubMed

    Iskra, Igor; Droste, Ronald

    2007-06-01

    Development of TMDLs (total maximum daily loads) is often facilitated by using the software system BASINS (Better Assessment Science Integrating point and Nonpoint Sources). One of the key elements of BASINS is the watershed model HSPF (Hydrological Simulation Program Fortran) developed by USEPA. Calibration of HSPF is a very tedious and time consuming task, more than 100 parameters are involved in the calibration process. In the current research, three non-linear automatic optimization techniques are applied and compared, as well an efficient way to calibrate HSPF is suggested. Parameter optimization using local and global optimization techniques for the watershed model is discussed. Approaches to automatic calibration of HSPF using the nonlinear parameter estimator PEST (Parameter Estimation Tool) with its Gauss-Marquardt-Levenberg (GML) method, Random multiple Search Method (RSM), and Shuffled Complex Evolution method developed at the University of Arizona (SCE-UA) are presented. Sensitivity analysis was conducted and the most and the least sensitive parameters were identified. It was noted that sensitivity depends on number of adjustable parameters. As more parameters were optimized simultaneously--a wider range of parameter values can maintain the model in the calibrated state. Impact of GML, RSM, and SCE-UA variables on ability to find the global minimum of the objective function (OF) was studied and the best variables are suggested. All three methods proved to be more efficient than manual HSPF calibration. Optimization results obtained by these methods are very similar, although in most cases RSM outperforms GML and SCE-UA outperforms RSM. GML is a very fast method, it can perform as well as SCE-UA when the variables are properly adjusted, initial guess is good and insensitive parameters are eliminated from the optimization process. SCE-UA is very robust and convenient to use. Logical definition of key variables in most cases leads to the global minimum.

  19. 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.

  20. 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

    2013-09-06

    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.

  1. 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).

  2. Application of an optimization technique to a physically based erosion model

    NASA Astrophysics Data System (ADS)

    Santos, Celso A. G.; Srinivasan, Vajapeyam S.; Suzuki, Koichi; Watanabe, Masahiro

    2003-04-01

    The difficulties involved in calibration of physically based erosion models have been partly attributable to the lack of robust optimization tools. This paper presents the essential concepts and application to optimize channel and plane parameters in an erosion model, with a global optimization method known as the SCE-UA (Duan et al., 1992. Water Resources Research 28(4): 1015-1031), which has recently shown promise as an effective and efficient optimization method for calibrating watershed models. It is based on the simplex method, and in order to improve its efficiency by making the simplex expand in a direction of more favourable conditions, or contract if a move was taken in a direction of less favourable conditions, new evolution steps have been introduced. The physically based erosion model that was chosen is called WESP (watershed erosion simulation program), developed by Lopes and Lane (1988. In Sediment Budgets, Bordas MP, Walling DE (eds). IAHS Publication no. 174. IAHS: Wallingford). The optimization technique was tested with the field data collected in an experimental watershed located in a semi-arid region of Brazil. On the basis of these results, the recommended erosion parameter values for a semi-arid region are given, which could serve as an initial estimate for other similar areas.

  3. Dynamic optimization of distributed biological systems using robust and efficient numerical techniques

    PubMed Central

    2012-01-01

    Background Systems biology allows the analysis of biological systems behavior under different conditions through in silico experimentation. The possibility of perturbing biological systems in different manners calls for the design of perturbations to achieve particular goals. Examples would include, the design of a chemical stimulation to maximize the amplitude of a given cellular signal or to achieve a desired pattern in pattern formation systems, etc. Such design problems can be mathematically formulated as dynamic optimization problems which are particularly challenging when the system is described by partial differential equations. This work addresses the numerical solution of such dynamic optimization problems for spatially distributed biological systems. The usual nonlinear and large scale nature of the mathematical models related to this class of systems and the presence of constraints on the optimization problems, impose a number of difficulties, such as the presence of suboptimal solutions, which call for robust and efficient numerical techniques. Results Here, the use of a control vector parameterization approach combined with efficient and robust hybrid global optimization methods and a reduced order model methodology is proposed. The capabilities of this strategy are illustrated considering the solution of a two challenging problems: bacterial chemotaxis and the FitzHugh-Nagumo model. Conclusions In the process of chemotaxis the objective was to efficiently compute the time-varying optimal concentration of chemotractant in one of the spatial boundaries in order to achieve predefined cell distribution profiles. Results are in agreement with those previously published in the literature. The FitzHugh-Nagumo problem is also efficiently solved and it illustrates very well how dynamic optimization may be used to force a system to evolve from an undesired to a desired pattern with a reduced number of actuators. The presented methodology can be used for the

  4. 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

  5. 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.

  6. A new surgical management for oro-antral communication: the resorbable guided tissue regeneration membrane--bone substitute sandwich technique.

    PubMed

    Ogunsalu, C

    2005-09-01

    This paper describes a new technique for the closure of oro-antral fistula/communication, in which both hard tissue (bone) and soft tissue closure is achieved. The sandwich technique utilizes a suitable bone grafting material sandwiched between two sheaths of Biogide (a resorbable membrane) for the hard tissue closure of oro-antral communication post traumatic exodontia. The bone grafting material utilized for this case was Bio-oss. The result obtained was excellent with regeneration of sufficient bony tissue to allow placement of an endosseous implant. This sandwich technique is a simple and excellent technique for the closure of oro-antral communication, especially when subsequent placement of endosseous implant is considered without the need of donor site surgery for bone grafting. The otorhinolaryngologists and oral and maxillofacial surgeons should find this technique very useful in the closure of oro-antral fistulae.

  7. Estimation of the stapes-bone thickness in the stapedotomy surgical procedure using a machine-learning technique.

    PubMed

    Kaburlasos, V G; Petridis, V; Brett, P N; Baker, D A

    1999-12-01

    Stapedotomy is a surgical procedure aimed at the treatment of hearing impairment due to otosclerosis. The treatment consists of drilling a hole through the stapes bone in the inner ear in order to insert a prosthesis. Safety precautions require knowledge of the nonmeasurable stapes thickness. The technical goal herein has been the design of high-level controls for an intelligent mechatronics drilling tool in order to enable the estimation of stapes thickness from measurable drilling data. The goal has been met by learning a map between drilling features, hence no model of the physical system has been necessary. Learning has been achieved as explained in this paper by a scheme, namely the d-sigma Fuzzy Lattice Neurocomputing (d sigma-FLN) scheme for classification, within the framework of fuzzy lattices. The successful application of the d sigma-FLN scheme is demonstrated in estimating the thickness of a stapes bone "on-line" using drilling data obtained experimentally in the laboratory.

  8. Optimizing charge breeding techniques for ISOL facilities in Europe: Conclusions from the EMILIE project

    SciTech Connect

    Delahaye, P. Jardin, P.; Maunoury, L.; Angot, J.; Lamy, T.; Thuillier, T.; Celona, L.; Choinski, J.; Gmaj, P.; Koivisto, H.; Kolhinen, V.; Tarvainen, O.; Vondrasek, R.; Wenander, F.

    2016-02-15

    The present paper summarizes the results obtained from the past few years in the framework of the Enhanced Multi-Ionization of short-Lived Isotopes for Eurisol (EMILIE) project. The EMILIE project aims at improving the charge breeding techniques with both Electron Cyclotron Resonance Ion Sources (ECRIS) and Electron Beam Ion Sources (EBISs) for European Radioactive Ion Beam (RIB) facilities. Within EMILIE, an original technique for debunching the beam from EBIS charge breeders is being developed, for making an optimal use of the capabilities of CW post-accelerators of the future facilities. Such a debunching technique should eventually resolve duty cycle and time structure issues which presently complicate the data-acquisition of experiments. The results of the first tests of this technique are reported here. In comparison with charge breeding with an EBIS, the ECRIS technique had lower performance in efficiency and attainable charge state for metallic ion beams and also suffered from issues related to beam contamination. In recent years, improvements have been made which significantly reduce the differences between the two techniques, making ECRIS charge breeding more attractive especially for CW machines producing intense beams. Upgraded versions of the Phoenix charge breeder, originally developed by LPSC, will be used at SPES and GANIL/SPIRAL. These two charge breeders have benefited from studies undertaken within EMILIE, which are also briefly summarized here.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. Grid optimization and multigrid techniques for fluid flow and transport problems

    NASA Astrophysics Data System (ADS)

    Pardhanani, Anand L.

    1992-01-01

    Special numerical techniques for the efficient and accurate solution of fluid flow and certain other transport processes are investigated. These include adaptive redistribution and optimization of computational grids, multigrid techniques for convection-diffusion problems, and multigrid time-marching methods for non-stationary and nonlinear problems. The grid optimization strategy is based on constructing and minimizing a mathematical objective function which defines the desired grid properties. For convection-diffusion problems, it is demonstrated that standard multigrid techniques fail when the coarse grids violate mesh-size restrictions. A variety of alternate multigrid strategies are explored, including artificial dissipation, fine grid pre-elimination, self-adjoint formulation, defect correction, and combination with grid redistribution. Multilevel techniques are also developed for time-dependent problems, including evolution problems with non-steady or transient solutions, and steady-state problems solved with artificial time-marching. Both explicit and implicit integration schemes are investigated, and it is shown that significant performance improvements can be gained with the use of multigrid. These techniques are implemented and tested on representative model problems as well as practical applications of current research interest. The grid investigations involve optimization in model problems, and in large-scale 3-D aircraft wing-body configurations. The multigrid applications range from model convection-diffusion problems, to time-dependent problems, to coupled nonlinear problems in two major application areas. The first application involves simulating spatio-temporal patterns in a coupled, nonlinear, reaction-diffusion problem that models the behavior of the Belousov-Zhabotinskii reaction. This multi-species reaction, which exhibits intricate patterns in laboratory experiments, has attracted considerable interest in the field of nonlinear dynamics. The

  16. 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

  17. Optimized scheduling technique of null subcarriers for peak power control in 3GPP LTE downlink.

    PubMed

    Cho, Soobum; 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.

  18. [Optimization on alcohol precipitation techniques of Liuwei Dihuang decoction by response surface methodology].

    PubMed

    Yan, Ming; Wei, Ying-chun; Li, Xue-feng; Meng, Jin; Wu, Yun; Xiao, Wei

    2015-10-01

    The theoretical basis of the alcohol precipitation process control was provided, the alcohol precipitation was optimized and the relationship equation was got. The monod glycoside, loganin and paeoniflorin were used as the evaluation indexes to determine the impact factors of alcohol precipitation techniques of Liuwei Dihuang decoction by the Plackett-Burman experimental design and the levels of non-significant factors were identified. Then, Box-Behnken response surface methodology was used to research and discuss the critical process parameters influence the effect of alcohol precipitation and draw interaction between key process parameters and the correlation equation with index components. Through the establishment and solving the quadratic regression model of composite score, the optimum preparation conditions of alcohol precipitation techniques of liuwei were as follows: stirring speed was 580 r x min(-1), standing time was 17 hours, alcohol concentration was 34%, the density of Liuwei Dihuang decoction was 1.13. The response surface methodology for optimized alcohol precipitation techniques of Liuwei Dihuang decoction is. reasonable and feasible.

  19. 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.

  20. Development of a parameter optimization technique for the design of automatic control systems

    NASA Technical Reports Server (NTRS)

    Whitaker, P. H.

    1977-01-01

    Parameter optimization techniques for the design of linear automatic control systems that are applicable to both continuous and digital systems are described. The model performance index is used as the optimization criterion because of the physical insight that can be attached to it. The design emphasis is to start with the simplest system configuration that experience indicates would be practical. Design parameters are specified, and a digital computer program is used to select that set of parameter values which minimizes the performance index. The resulting design is examined, and complexity, through the use of more complex information processing or more feedback paths, is added only if performance fails to meet operational specifications. System performance specifications are assumed to be such that the desired step function time response of the system can be inferred.

  1. 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.

  2. a High-Level Technique for Estimation and Optimization of Leakage Power for Full Adder

    NASA Astrophysics Data System (ADS)

    Shrivas, Jayram; Akashe, Shyam; Tiwari, Nitesh

    2013-06-01

    Optimization of power is a very important issue in low-voltage and low-power application. In this paper, we have proposed power gating technique to reduce leakage current and leakage power of one-bit full adder. In this power gating technique, we use two sleep transistors i.e., PMOS and NMOS. PMOS sleep transistor is inserted between power supply and pull up network. And NMOS sleep transistor is inserted between pull down network and ground terminal. These sleep transistors (PMOS and NMOS) are turned on when the circuit is working in active mode. And sleep transistors (PMOS and NMOS) are turned off when circuit is working in standby mode. We have simulated one-bit full adder and compared with the power gating technique using cadence virtuoso tool in 45 nm technology at 0.7 V at 27°C. By applying this technique, we have reduced leakage current from 2.935 pA to 1.905 pA and leakage power from 25.04μw to 9.233μw. By using this technique, we have reduced leakage power up to 63.12%.

  3. Generation expansion planning: an analysis of techniques to expedite the approach to an optimal solution

    SciTech Connect

    Lubbers, R.H.

    1982-01-01

    The subject of this dissertation is an analysis of techniques which can be used to expedite the approach to an optimal plan for the installation of new generating units in an electric utility system, using the WASP (Wein Automatic System Planning) program. The objectives are three-fold: to present the details and results of a sensitivity study performed using WASP; to analyze and overcome the logistical problems resulting in the excessive computation time required to complete a generation expansion study using WASP; and to compare WASP's results with those of another widely used generation expansion planning program - OGP (Optimized Generation Planning) - and to analyze how the differing modelling methodologies impact those results. The first objective was accomplished by providing a detailed description of the collection and preparation of input data for a sensitivity study and by reporting on trends noted when various economic and peak load growth data were varied. Accomplishment of the second objective led to the demonstration of three techniques for expediting WASP analyses, namely: employing a yearly optimization scheme, involving the weighting of the objective function with estimated operation and capital costs incurred during a static operation period, to arrive at an initial expansion plan; modelling generating units as a single block of capacity in order to decrease computation time with little sacrifice in precision; and using the static operation period to reduce end effects of the dynamic optimization. The third objective was accomplished through the comparison of the results of a sample planning study carried out using both WASP and OGP. Despite several areas in which modelling methodologies differed, startingly similar results were obtained.

  4. 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)