Histological evaluation and optimization of surgical vessel sealing systems

NASA Astrophysics Data System (ADS)

Lathrop, Robert; Ryan, Thomas; Gaspredes, Jonathan; Woloszko, Jean; Coad, James E.

2017-02-01

Surgical vessel sealing systems are widely used to achieve hemostasis and dissection in open surgery and minimally invasive, laparoscopic surgery. This enabling technology was developed about 17 years ago and continues to evolve with new devices and systems achieving improved outcomes. Histopathological assessment of thermally sealed tissues is a valuable tool for refining and comparing performance among surgical vessel sealing systems. Early work in this field typically assessed seal time, burst rate, and failure rate (in-situ). Later work compared histological staining methods with birefringence to assess the extent of thermal damage to tissues adjacent to the device. Understanding the microscopic architecture of a sealed vessel is crucial to optimizing the performance of power delivery algorithms and device design parameters. Manufacturers rely on these techniques to develop new products. A system for histopathological evaluation of vessels and sealing performance was established, to enable the direct assessment of a treatment's tissue effects. The parameters included the commonly used seal time, pressure burst rate and failure rate, as well as extensions of the assessment to include its likelihood to form steam vacuoles, adjacent thermal effect near the device, and extent of thermally affected tissue extruded back into the vessel lumen. This comprehensive assessment method provides an improved means of assessing the quality of a sealed vessel and understanding the exact mechanisms which create an optimally sealed vessel.

Open Tibial Inlay PCL Reconstruction: Surgical Technique and Clinical Outcomes.

PubMed

Vellios, Evan E; Jones, Kristofer J; McAllister, David R

2018-06-01

To review the current literature on clinical outcomes following open tibial inlay posterior cruciate ligament (PCL) reconstruction and provide the reader with a detailed description of the author's preferred surgical technique. Despite earlier biomechanical studies which demonstrated superiority of the PCL inlay technique when compared to transtibial techniques, recent longitudinal cohort studies have shown no significant differences in clinical or functional outcomes at 10-year follow-up. Furthermore, no significant clinical differences have been shown between graft types used and/or single- versus double-bundle reconstruction methods. The optimal treatment for the PCL-deficient knee remains unclear. Open tibial inlay PCL reconstruction is safe, reproducible, and avoids the "killer turn" that may potentially lead to graft weakening and failure seen in transtibial reconstruction methods. No significant differences in subjective outcomes or clinical laxity have been shown between single-bundle versus double-bundle reconstruction methods.

Modeling surgical tool selection patterns as a "traveling salesman problem" for optimizing a modular surgical tool system.

PubMed

Nelson, Carl A; Miller, David J; Oleynikov, Dmitry

2008-01-01

As modular systems come into the forefront of robotic telesurgery, streamlining the process of selecting surgical tools becomes an important consideration. This paper presents a method for optimal queuing of tools in modular surgical tool systems, based on patterns in tool-use sequences, in order to minimize time spent changing tools. The solution approach is to model the set of tools as a graph, with tool-change frequency expressed as edge weights in the graph, and to solve the Traveling Salesman Problem for the graph. In a set of simulations, this method has shown superior performance at optimizing tool arrangements for streamlining surgical procedures.

Optimizing the patient for surgical treatment of the wound.

PubMed

Myers, Wesley T; Leong, Mimi; Phillips, Linda G

2007-10-01

Plastic surgeons are consulted often to close wounds that fail or are difficult to heal. Optimizing the patient's medical condition before surgical closure of a wound can mean the difference between a successful outcome and an undesirable one. It is imperative that plastic surgeons have an extensive knowledge of the modifiable risk factors affecting the wound-healing process and their subsequent complications. This knowledge allows the surgeon to tailor the treatment options and intervene when appropriate to optimize outcomes for successful surgical closure of a wound. Whether the impairments to wound healing and closure are local or systemic, they must be addressed appropriately.

Neuronavigation. Principles. Surgical technique.

PubMed Central

Ivanov, Marcel; Vlad Ciurea, Alexandru

2009-01-01

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

Optimal primary surgical treatment for advanced epithelial ovarian cancer.

PubMed

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

2011-08-10

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

Development of the implant surgical technique and assessment rating system

PubMed Central

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

2012-01-01

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

Mathematical Optimization Techniques

NASA Technical Reports Server (NTRS)

Bellman, R. (Editor)

1963-01-01

The papers collected in this volume were presented at the Symposium on Mathematical Optimization Techniques held in the Santa Monica Civic Auditorium, Santa Monica, California, on October 18-20, 1960. The objective of the symposium was to bring together, for the purpose of mutual education, mathematicians, scientists, and engineers interested in modern optimization techniques. Some 250 persons attended. The techniques discussed included recent developments in linear, integer, convex, and dynamic programming as well as the variational processes surrounding optimal guidance, flight trajectories, statistical decisions, structural configurations, and adaptive control systems. The symposium was sponsored jointly by the University of California, with assistance from the National Science Foundation, the Office of Naval Research, the National Aeronautics and Space Administration, and The RAND Corporation, through Air Force Project RAND.

Evolution of surgical techniques for a progressive risk reduction.

PubMed

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

2017-07-18

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

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

PubMed

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

2007-10-01

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

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

Optimizing light delivery for a photoacoustic surgical system

NASA Astrophysics Data System (ADS)

Eddins, Blackberrie; Lediju Bell, Muyinatu A.

2017-03-01

This work explores light delivery optimization for a photoacoustic surgical system previously proposed to provide real-time, intraoperative visualization of the internal carotid arteries hidden by bone during minimally invasive neurosurgeries. Monte Carlo simulations were employed to study 3D light propagation in tissue. For a 2.4 mm diameter drill shaft and 2.9 mm spherical drill tip, the optimal fiber distance from the drill shaft was 2 mm, determined from the maximum normalized fluence seen by the artery. A single fiber was insufficient to deliver light to arteries separated by a minimum of 8 mm. Using similar drill geometry and the optimal 2 mm fiber-to-drill shaft distance, Zemax ray tracing simulations were employed to propagate a 950 nm wavelength Gaussian beam through one or more 600 μm core diameter optical fibers, and the resulting optical beam profile was detected on the representative bone surface. For equally spaced fibers, a single merged optical profile formed with 7 or more fibers, determined by thresholding the resulting light profile images at 1/e times the maximum intensity. The corresponding spot size was larger than that of a single fiber transmitting the same input energy, thus reducing the fluence delivered to the sphenoid bone and enabling higher energies within safety limits. A prototype was designed and built based on these optimization parameters. The methodology we used to optimize our light delivery system to surround surgical tools is generalizable to multiple interventional photoacoustic applications.

Multiple tenting techniques improve dead space obliteration in the surgical treatment for patients with giant calcified chronic subdural hematoma.

PubMed

Juan, Wei-Sheng; Tai, Shih-Huang; Hung, Yu-Chang; Lee, E-Jian

2012-04-01

Calcified chronic subdural hematoma (CCSDH), or "armored brain," is a rare disease entity. The optimal surgical procedure for CCSDH has not been established because it is hard to obtain brain re-expansion after surgery. In particular, a large CCSDH is difficult to completely extirpate, and the residual rigid inner and outer membranes facilitates dead space retention and hematoma recurrence. We introduce the use a multiple suturing technique to tent the residual outer and inner membranes onto the dura matter so as to obliterate dead space after surgical treatment for CCSDH. Neuroimaging and surgical reports with illustrative images from two cases are shown. Two patients were admitted to our intensive care unit more than 10 years apart from their ventriculoperitoneal (V-P) shunt placements. The first patient presented with clinical signs of increased intracranial pressure. The second patient had a large CCSDH as a concomitant finding with ruptured aneurysmal subarachnoid hemorrhage. Computerized cranial tomography demonstrated large hematoma cavities with thick calcified inner membranes. After neurosurgical intervention by craniotomy and optimal resection of calcified membranes and muddy blood clot, we tented the residual calcified inner and outer membranes onto the dura matter by multiple sutures to reduce dead space accumulation. Postoperatively, the two patients had improved clinical symptoms along with much reduced hematoma cavity in imaging examinations. We reported an alternative technique using multiple tenting procedures to improve dead space obliteration after surgical treatment for patients with a large CCSDH presenting as a late complication after V-P shunting.

Ahmed glaucoma valve implant: surgical technique and complications.

PubMed

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.

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

Surgical Approaches to Chronic Pancreatitis: Indications and Techniques.

PubMed

Dua, Monica M; Visser, Brendan C

2017-07-01

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

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

PubMed

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

2014-04-01

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

Optimization of Collision Detection in Surgical Simulations

NASA Astrophysics Data System (ADS)

Custură-Crăciun, Dan; Cochior, Daniel; Neagu, Corneliu

2014-11-01

Just like flight and spaceship simulators already represent a standard, we expect that soon enough, surgical simulators should become a standard in medical applications. A simulations quality is strongly related to the image quality as well as the degree of realism of the simulation. Increased quality requires increased resolution, increased representation speed but more important, a larger amount of mathematical equations. To make it possible, not only that we need more efficient computers, but especially more calculation process optimizations. A simulator executes one of the most complex sets of calculations each time it detects a contact between the virtual objects, therefore optimization of collision detection is fatal for the work-speed of a simulator and hence in its quality

Review of Surgical Techniques of Experimental Renal Transplantation in Rats.

PubMed

Shrestha, Badri; Haylor, John

2017-08-01

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

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

PubMed

Hoag, Nathan; Gani, Johan; Chee, Justin

2016-07-01

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

Acute bacterial endocarditis. Optimizing surgical results.

PubMed

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

1992-11-01

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

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

PubMed

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

2016-07-01

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

[Which surgical technique should we perform for benign renal disease in children?].

PubMed

Saura, L; Aparicio, L García; Julià, V; Ribó, J M; Rovira, J; Rodó, J; Tarrado, X; Prat, J; Cáceres, F; Morales, L

2007-01-01

The aim of this paper is to analyze our experience in different surgical techniques to perform a nephrectomy for benign renal diseases in children. From 1993 to 2005 we have performed 98 nephrectomies. We have three groups of patients depending on the surgical technique: open nephrectomy (ON), transperitoneal laparoscopic nephrectomy (TLN) and retroperitoneal laparoscopic nephrectomy (RLN). ON was performed in 36 patients. Mean age was 3.3 years. TLN was performed in 39 patients. Mean age was 4.7 years old. RLN was performed in 23 patients. Mean age was 3.6 years old. Criteria to nephrectomy was a renographic function under 19%. We have compared the three surgical techniques in relation with surgical time and mean hospital stay. Mean operative time was 126.2 minutes in ON, 132.3 minutes in TLN and 134.1 minutes in RLN. Mean stay was 5.02 days in ON, 2.35 days in TLN and 1.86 days in RLN. The median hospital stay of the ON group is significantly longer than that of NLT and NR groups (p < 0.05). However, there are no differences related to surgical time between all the groups. Nephrectomy may be performed for benign disease in children using less invasive surgical techniques. They are associated with minimal morbidity, minimal postoperative discomfort, improve cosmesis and a shorter hospital stay. However, we haven't found differences between TLN and RLN.

Primary surgical excision for pediatric orbital capillary hemangioma.

PubMed

Krema, Hatem

2015-05-01

We report the technique and outcome of surgical excision of subcutaneous orbital capillary hemangioma causing eye globe displacement in two children. Primary surgical excision was performed with blunt dissection along the tumor walls using a cotton-tipped applicator as the dissecting tool with simultaneous outward gentle traction on the tumor wall. Despite the deep and extensive orbital involvement, complete excision of the hemangiomas was achievable with this technique, which permitted excellent visualization of the surgical planes throughout the procedures. Deep and extensive pediatric orbital capillary hemangioma can be surgically excised with the suggested technique, which obviates the need for intralesional or systemic medical therapy, yielding optimal cosmetic and functional outcomes, shortly after surgery.

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

PubMed

Mirshahi, A; Scharioth, G B

2009-01-01

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

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

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

PubMed

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

2016-04-01

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

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

PubMed

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

2017-11-01

Preoperative preparation of patients with Crohn's disease is challenging and there are no specific guidelines regarding nutritional support. The aim of this study was to assess whether preoperative nutritional support influenced the postoperative outcome. A retrospective, cohort study including all Crohn's disease patients who underwent abdominal surgery between 2008 and 2014 was conducted. Patients' characteristics and clinical and surgical data were recorded and analyzed. Eighty-seven patients were included in the study. Thirty-seven patients (42.5%) received preoperative nutritional support (mean albumin level 3.14 vs. 3.5 mg/dL in the non-optimized group; p < 0.02) to optimize their nutritional status prior to surgery. Preoperative albumin level, after adequate nutritional preparation, was similar between the 2 groups. The 2 groups differ neither in demographic and surgical data, overall post-op complication (p = 0.85), Clavien-Dindo score (p = 0.42), and length of stay (p = 0.1). Readmission rate was higher in the non-optimized group (p = 0.047). Nutritional support can minimize postoperative complications in patients with low albumin levels. Nutritional status should be optimized in order to avoid hazardous complications. © 2017 S. Karger AG, Basel.

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

Endoscopic colloid cyst excision: surgical techniques and nuances.

PubMed

Azab, Waleed Abdelfattah; Najibullah, Mustafa; Yosef, Waleed

2017-06-01

Endoscopic excision of colloid cysts is currently well established as a minimally invasive and highly effective technique that is associated with less morbidity in comparison to microsurgical resection. Operative charts and videos of patients undergoing endoscopic colloid cyst excision were retrieved from the senior author's database of endoscopic procedures and reviewed. This revealed nine trans-foraminal and three trans-septal procedures. Description of the surgical techniques was then formulated. Variation of the technique is based on the specific patho-anatomical features of the colloid cyst being resected. For the trans-foraminal approach, we think that the rotational technique is associated with a more complete removal of the cyst wall and consequently lower recurrence rate.

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

PubMed

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

2016-10-01

On the 60 th 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.

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

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.

An effective visualization technique for depth perception in augmented reality-based surgical navigation.

PubMed

Choi, Hyunseok; Cho, Byunghyun; Masamune, Ken; Hashizume, Makoto; Hong, Jaesung

2016-03-01

Depth perception is a major issue in augmented reality (AR)-based surgical navigation. We propose an AR and virtual reality (VR) switchable visualization system with distance information, and evaluate its performance in a surgical navigation set-up. To improve depth perception, seamless switching from AR to VR was implemented. In addition, the minimum distance between the tip of the surgical tool and the nearest organ was provided in real time. To evaluate the proposed techniques, five physicians and 20 non-medical volunteers participated in experiments. Targeting error, time taken, and numbers of collisions were measured in simulation experiments. There was a statistically significant difference between a simple AR technique and the proposed technique. We confirmed that depth perception in AR could be improved by the proposed seamless switching between AR and VR, and providing an indication of the minimum distance also facilitated the surgical tasks. Copyright © 2015 John Wiley & Sons, Ltd.

Surgical Site Infiltration for Abdominal Surgery: A Novel Neuroanatomical-based Approach

PubMed Central

Janis, Jeffrey E.; Haas, Eric M.; Ramshaw, Bruce J.; Nihira, Mikio A.; Dunkin, Brian J.

2016-01-01

Background: Provision of optimal postoperative analgesia should facilitate postoperative ambulation and rehabilitation. An optimal multimodal analgesia technique would include the use of nonopioid analgesics, including local/regional analgesic techniques such as surgical site local anesthetic infiltration. This article presents a novel approach to surgical site infiltration techniques for abdominal surgery based upon neuroanatomy. Methods: Literature searches were conducted for studies reporting the neuroanatomical sources of pain after abdominal surgery. Also, studies identified by preceding search were reviewed for relevant publications and manually retrieved. Results: Based on neuroanatomy, an optimal surgical site infiltration technique would consist of systematic, extensive, meticulous administration of local anesthetic into the peritoneum (or preperitoneum), subfascial, and subdermal tissue planes. The volume of local anesthetic would depend on the size of the incision such that 1 to 1.5 mL is injected every 1 to 2 cm of surgical incision per layer. It is best to infiltrate with a 22-gauge, 1.5-inch needle. The needle is inserted approximately 0.5 to 1 cm into the tissue plane, and local anesthetic solution is injected while slowly withdrawing the needle, which should reduce the risk of intravascular injection. Conclusions: Meticulous, systematic, and extensive surgical site local anesthetic infiltration in the various tissue planes including the peritoneal, musculofascial, and subdermal tissues, where pain foci originate, provides excellent postoperative pain relief. This approach should be combined with use of other nonopioid analgesics with opioids reserved for rescue. Further well-designed studies are necessary to assess the analgesic efficacy of the proposed infiltration technique. PMID:28293525

Preoperative Optimization of Total Joint Arthroplasty Surgical Risk: Obesity.

PubMed

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

2016-08-01

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

Optimal parameters for arterial repair using light-activated surgical adhesives.

PubMed

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

2003-01-01

The clinical acceptance of laser-tissue repair techniques is dependent on the reproducibility of viable repairs. Reproducibility is dependent on two factors: (i) the choice of materials to be used as the adhesive; and (ii) obtaining temperatures high enough to cause protein denaturation at the vital tissue interface without causing excessive thermal damage to the surrounding tissue. The use of a polymer scaffold as a carrier for the protein solder provides for uniform application of the solder to the tissue, thus allowing for pre-selection of optimal laser parameters. The scaffold also facilitates precise tissue alignment and ease of clinical application. In addition, the scaffold can be doped with various pharmaceuticals such as hemostatic and thrombogenic agents to aid wound healing. An ex vivo study was performed to correlate solder and tissue temperature with the tensile strength of arterial repairs formed using scaffold-enhanced light-activated surgical adhesives. Previous studies by our group using solid protein solder without the scaffold indicate that a solder/tissue, interface temperature of 65 degrees C is optimal. Using this parameter as a benchmark, laser irradiance was varied and temperatures were recorded at the surface and at the tissue interface of scaffold-enhanced protein solder using an infrared temperature monitoring system, designed by the researchers, and a type-K thermocouple, respectively.

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.

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

PubMed

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

2008-01-01

Some surgical pathologies eventually require intestinal resection. This may lead to an extended procedure such as leaving 30 cm of proximal jejunum and left and sigmoid colon. One of the most important consequences of this type of resection is "intestinal failure" or short bowel syndrome. This complex syndrome leads to different metabolic and water and acid/base imbalances, as well as nutritional and immunological challenges along with the problem accompanying an abdomen subjected to many surgical procedures and high mortality. Many surgical techniques have been developed to improve quality of life of patients. We designed a non-transplant surgical approach and performed the procedure on two patients with postoperative short bowel syndrome with <40 cm of proximal jejunum and left colon. There are a variety of non-transplant surgical procedures that, due to their complex technique or high mortality rate, have not resolved this important problem. However, the technique we present in this work can be performed by a large number of surgeons. The procedure has a low morbimortality rate and offers the opportunity for better control of metabolic and acid/base balance, intestinal transit and proper nutrition. We consider that this technique offers a new alternative for the complex management required by patients with short bowel syndrome and facilitates their long-term nutritional control.

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. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

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.

Advances in surgical techniques for resection of childhood cerebellopontine angle ependymomas are key to survival.

PubMed

Sanford, Robert A; Merchant, Thomas E; Zwienenberg-Lee, Marike; Kun, Larry E; Boop, Frederick A

2009-10-01

Childhood cerebellopontine angle (CPA) ependymoma is an uncommon anatomical variant of posterior fossa ependymoma. In infants and young children, the tumor often goes undetected until it causes hydrocephalus. As CPA ependymomas grow, they distort the anatomy and encase cranial nerves and vessels, thereby making resection a formidable surgical challenge. The purpose of this paper is to describe the surgical technique used to achieve gross total resection (GTR) of CPA ependymomas and demonstrate improved survival in these patients. Surgical techniques used for GTR in 45 patients with CPA ependymoma treated from 1997 to 2008 are described. Results of those procedures are compared with data from 11 patients who previously underwent surgical resection (1985-1995). We achieved GTR in 43 (95.6%) patients and near-total resection in two (4.4%); the probability of progression-free survival was 53.8%, and that of overall survival was 64%. Our novel surgical techniques greatly improve central nervous system function and survival among pediatric patients with CPA ependymoma.

[Optimizing primary total hip replacement--a technique to effect saving of manpower].

PubMed

Huber, J F; Rink, M; Broger, I; Zumstein, M; Ruflin, G B

2003-01-01

Development of a standardized surgical technique for total hip replacement thereby saving manpower (one assistant) by using a retractor system. Total hip replacement is performed with the patient in a true lateral position on a tunnel cushion. By means of a direct lateral approach the pelvitrochanteric muscles are partially detached using an omega-shaped cut. The Bookwalter retractor is fixed dorsally on the operating table. The ring is centered keeping the greater trochanter in the middle. The Hohmann retractors are fixed to the ring to sufficiently expose the acetabulum. To insert the femoral stem the ring needs to be opened dorsally and the patient's leg is bent 90 degrees in the hip and the knee over the tunnel cushion. The muscles inserting at the greater trochanter are retracted by a separate Hohmann retractor with weight. In a case control study with matched pairs the patients treated with this technique were compared with those treated in supine position with the transgluteal approach. The number of assistants required and the operating time were assessed. All the hip replacements with the patient in side position were performed with one assistant, in supine position with two assistants. The operating time did not differ significantly (supine position 110 min/side position 112 min). The complication rate in both groups was comparable (one secondary wound healing, one transient ischalgia). The process of total hip replacement can be optimized. The described technique allows to spare one surgical assistant without prolonging the operating time.

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)

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

PubMed

Shrestha, Badri Man; Haylor, John

2017-11-15

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

Surgical Techniques at Cesarean Delivery: A U.S. Survey

PubMed Central

Lyell, Deirdre J.; Power, Michael; Murtough, Katie; Ness, Amen; Anderson, Britta; Erickson, Kristine; Schulkin, Jay

2016-01-01

Objective  To assess the frequency of surgical techniques at cesarean delivery (CD) among U.S. obstetricians. Methods  Members of the American College of Obstetrician Gynecologists were randomly selected and e-mailed an online survey that assessed surgical closure techniques, demographics, and reasons. Data were analyzed using SPSS (IBM Corp., Armonk, New York, United States), descriptive statistics, and analysis of variance. Results  Our response rate was 53%, and 247 surveys were analyzed. A similar number of respondents either “always or usually” versus “rarely or never” reapproximate the rectus muscles (38.4% versus 43.3%, p  = 0.39), and close parietal peritoneum (42.5% versus 46.9%, p  = 0.46). The most frequently used techniques were double-layer hysterotomy closure among women planning future children (73.3%) and suturing versus stapling skin (67.6%); the least frequent technique was closure of visceral peritoneum (12.2%). Surgeons who perform double-layer hysterotomy closure had fewer years in practice (15.0 versus 18.7 years, p  = 0.021); surgeons who close visceral peritoneum were older (55.5 versus 46.4 years old, p  < 0.001) and had more years in practice (23.8 versus 13.8 years practice; p  < 0.001). Conclusion  Similar numbers of obstetricians either reapproximate or leave open the rectus muscles and parietal peritoneum at CD, suggesting that wide variation in practice exists. Surgeon demographics and safety concerns play a role in some techniques. PMID:28825004

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.

Image-Based Patient-Specific Ventricle Models with Fluid-Structure Interaction for Cardiac Function Assessment and Surgical Design Optimization

PubMed Central

Tang, Dalin; Yang, Chun; Geva, Tal; del Nido, Pedro J.

2010-01-01

Recent advances in medical imaging technology and computational modeling techniques are making it possible that patient-specific computational ventricle models be constructed and used to test surgical hypotheses and replace empirical and often risky clinical experimentation to examine the efficiency and suitability of various reconstructive procedures in diseased hearts. In this paper, we provide a brief review on recent development in ventricle modeling and its potential application in surgical planning and management of tetralogy of Fallot (ToF) patients. Aspects of data acquisition, model selection and construction, tissue material properties, ventricle layer structure and tissue fiber orientations, pressure condition, model validation and virtual surgery procedures (changing patient-specific ventricle data and perform computer simulation) were reviewed. Results from a case study using patient-specific cardiac magnetic resonance (CMR) imaging and right/left ventricle and patch (RV/LV/Patch) combination model with fluid-structure interactions (FSI) were reported. The models were used to evaluate and optimize human pulmonary valve replacement/insertion (PVR) surgical procedure and patch design and test a surgical hypothesis that PVR with small patch and aggressive scar tissue trimming in PVR surgery may lead to improved recovery of RV function and reduced stress/strain conditions in the patch area. PMID:21344066

Trends in the Surgical Correction of Gynecomastia.

PubMed

Brown, Rodger H; Chang, Daniel K; Siy, Richard; Friedman, Jeffrey

2015-05-01

Gynecomastia refers to the enlargement of the male breast due to a proliferation of ductal, stromal, and/or fatty tissue. Although it is a common condition affecting up to 65% of men, not all cases require surgical intervention. Contemporary surgical techniques in the treatment of gynecomastia have become increasingly less invasive with the advent of liposuction and its variants, including power-assisted and ultrasound-assisted liposuction. These techniques, however, have been largely limited in their inability to address significant skin excess and ptosis. For mild to moderate gynecomastia, newer techniques using arthroscopic morcellation and endoscopic techniques promise to address the fibrous component, while minimizing scar burden by utilizing liposuction incisions. Nevertheless, direct excision through periareolar incisions remains a mainstay in treatment algorithms for its simplicity and avoidance of additional instrumentation. This is particularly true for more severe cases of gynecomastia requiring skin resection. In the most severe cases with significant skin redundancy and ptosis, breast amputation with free nipple grafting remains an effective option. Surgical treatment should be individualized to each patient, combining techniques to provide adequate resection and optimize aesthetic results.

A new surgical and technical approach in zygomatic implantology

PubMed Central

GRECCHI, F.; BIANCHI, A.E.; SIERVO, S.; GRECCHI, E.; LAURITANO, D.

2017-01-01

SUMMARY Purpose Different surgical approaches for zygomatic implantology using new designed implants are reported. Material and methods The surgical technique is described and two cases reported. The zygomatic fixture has a complete extrasinus path in order to preserve the sinus membrane and to avoid any post-surgical sinus sequelae. Results The surgical procedure allows an optimal position of the implant and consequently an ideal emergence of the fixture on the alveolar crest. Conclusion The surgical procedures and the zygomatic implant design reduce remarkably the serious post-operative sequelae due to the intrasinus path of the zygomatic fixtures. PMID:29876045

Fluorescence lifetime technique for surgical imaging, guidance and augmented reality (Conference Presentation)

NASA Astrophysics Data System (ADS)

Marcu, Laura

2017-02-01

The surgeon's limited ability to accurately delineate the tumor margin during surgical interventions is one key challenge in clinical management of cancer. New methods for guiding tumor resection decisions are needed. Numerous studies have shown that tissue autofluorescence properties have the potential to asses biochemical features associates with distinct pathologies in tissue and to distinguish various cancers from normal tissues. However, despite these promising reports, autofluorescence techniques were sparsely adopted in clinical settings. Moreover, when adopted they were primarily used for pre-operative diagnosis rather than guiding interventions. To address this need, we have researched and engineered instrumentation that utilizes label-free fluorescence lifetime contrast to characterize tissue biochemical features in vivo in patients and methodologies conducive to real-time (few seconds) diagnosis of tissue pathologies during surgical procedures. This presentation overviews clinically-compatible multispectral fluorescence lifetime imaging techniques developed in our laboratory and their ability to operate as stand-alone tools, integrated in a biopsy needle and in conjunction with the da Vinci surgical robot. We present pre-clinical and clinical studies in patients that demonstrate the potential of these techniques for intraoperative assessment of brain tumors and head and neck cancer. Current results demonstrate that intrinsic fluorescence signals can provide useful contrast for delineation distinct types of tissues including tumors intraoperatively. Challenges and solutions in the clinical implementation of these techniques are discussed.

Comparison between two surgical techniques for root coverage with an acellular dermal matrix graft.

PubMed

Andrade, Patrícia F; Felipe, Maria Emília M C; Novaes, Arthur B; Souza, Sérgio L S; Taba, Mário; Palioto, Daniela B; Grisi, Márcio F M

2008-03-01

The aim of this randomized, controlled, clinical study was to compare two surgical techniques with the acellular dermal matrix graft (ADMG) to evaluate which technique could provide better root coverage. Fifteen patients with bilateral Miller Class I gingival recession areas were selected. In each patient, one recession area was randomly assigned to the control group, while the contra-lateral recession area was assigned to the test group. The ADMG was used in both groups. The control group was treated with a broader flap and vertical-releasing incisions, and the test group was treated with the proposed surgical technique, without releasing incisions. The clinical parameters evaluated before the surgeries and after 12 months were: gingival recession height, probing depth, relative clinical attachment level and the width and thickness of keratinized tissue. There were no statistically significant differences between the groups for all parameters at baseline. After 12 months, there was a statistically significant reduction in recession height in both groups, and there was no statistically significant difference between the techniques with regard to root coverage. Both surgical techniques provided significant reduction in gingival recession height after 12 months, and similar results in relation to root coverage.

Understanding and Taking Control of Surgical Learning Curves.

PubMed

Gofton, Wade T; Papp, Steven R; Gofton, Tyson; Beaulé, Paul E

2016-01-01

As surgical techniques continue to evolve, surgeons will have to integrate new skills into their practice. A learning curve is associated with the integration of any new procedure; therefore, it is important for surgeons who are incorporating a new technique into their practice to understand what the reported learning curve might mean for them and their patients. A learning curve should not be perceived as negative because it can indicate progress; however, surgeons need to understand how to optimize the learning curve to ensure progress with minimal patient risk. It is essential for surgeons who are implementing new procedures or skills to define potential learning curves, examine how a reported learning curve may relate to an individual surgeon's in-practice learning and performance, and suggest methods in which an individual surgeon can modify his or her specific learning curve in order to optimize surgical outcomes and patient safety. A defined personal learning contract may be a practical method for surgeons to proactively manage their individual learning curve and provide evidence of their efforts to safely improve surgical practice.

Team Training (Training at Own Facility) versus Individual Surgeon's Training (Training at Trainer's Facility) When Implementing a New Surgical Technique: Example from the ONSTEP Inguinal Hernia Repair

PubMed Central

Laursen, Jannie

2014-01-01

Background. When implementing a new surgical technique, the best method for didactic learning has not been settled. There are basically two scenarios: the trainee goes to the teacher's clinic and learns the new technique hands-on, or the teacher goes to the trainee's clinic and performs the teaching there. Methods. An informal literature review was conducted to provide a basis for discussing pros and cons. We also wanted to discuss how many surgeons can be trained in a day and the importance of the demand for a new surgical procedure to ensure a high adoption rate and finally to apply these issues on a discussion of barriers for adoption of the new ONSTEP technique for inguinal hernia repair after initial training. Results and Conclusions. The optimal training method would include moving the teacher to the trainee's department to obtain team-training effects simultaneous with surgical technical training of the trainee surgeon. The training should also include a theoretical presentation and discussion along with the practical training. Importantly, the training visit should probably be followed by a scheduled visit to clear misunderstandings and fine-tune the technique after an initial self-learning period. PMID:25506078

Low Profile Mesh Plating for Patella Fractures: Video of a Novel Surgical Technique.

PubMed

Verbeek, Diederik O; Hickerson, Lindsay E; Warner, Stephen J; Helfet, David L; Lorich, Dean G

2016-08-01

Patella fractures can be challenging to treat particularly in the presence of inferior pole comminution. In this video we present a novel surgical technique for the treatment of patella fractures using a small fragment low profile mesh plate. Key points are the surgical exposure with direct visualization of the articular reduction, the preparation of the mesh plate to accommodate patellar anatomy and the augmentation of the construct using Krackow sutures to address inferior pole comminution. Low profile mesh plating allows for multiplanar fixation of patella fractures while avoiding implant and fixation problems related to tension band fixation. Our early experience with this technique is encouraging and it appears that this technique is useful for the treatment of the majority of patella fractures.

Code Optimization Techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

MAGEE,GLEN I.

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

Minimally invasive surgical techniques for stress incontinence surgery.

PubMed

Morley, Roland; Nethercliffe, Janine

2005-12-01

Minimally invasive techniques for surgical correction of stress incontinence date back to the late 1950s. Since that time there have been many developments to attempt to emulate the good results achieved by open surgery with less surgical morbidity. Needle suspensions have attempted to reposition the bladder neck in the same way as a colposuspension. However, although numerous variations have been described, they do not have the long-term outcomes of colposuspension. These variations, their complications and long-term outcome are discussed. Sling surgery, especially the tension-free vaginal tape (TVT), has probably had the largest impact on incontinence surgery in recent years, offering a procedure with low morbidity and, thus far in the medium term, outcomes comparable with those of more invasive procedures. This has led the TVT procedure to become the most common procedure performed worldwide for stress incontinence. With the benefit of lessons learnt from the use of synthetic material in the genitourinary tract, some worries remain with regard to the long-term complications of TVT. Other non-synthetic material should not be forgotten, and the advantages and disadvantages of various sling materials are compared. Injectables have an established place in the treatment of sphincter deficiency, though long-term results are poor compared to those of other procedures. Various materials used and the technique for their injection are discussed.

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

PubMed Central

Marchie, Anthony; Kumar, Arun; Catre, Melanio

2009-01-01

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

The impact of the alexander technique on improving posture and surgical ergonomics during minimally invasive surgery: pilot study.

PubMed

Reddy, Pramod P; Reddy, Trisha P; Roig-Francoli, Jennifer; Cone, Lois; Sivan, Bezalel; DeFoor, W Robert; Gaitonde, Krishnanath; Noh, Paul H

2011-10-01

One of the main ergonomic challenges during surgical procedures is surgeon posture. There have been reports of a high number of work related injuries in laparoscopic surgeons. The Alexander technique is a process of psychophysical reeducation of the body to improve postural balance and coordination, permitting movement with minimal strain and maximum ease. We evaluated the efficacy of the Alexander technique in improving posture and surgical ergonomics during minimally invasive surgery. We performed a prospective cohort study in which subjects served as their own controls. Informed consent was obtained. Before Alexander technique instruction/intervention subjects underwent assessment of postural coordination and basic laparoscopic skills. All subjects were educated about the Alexander technique and underwent post-instruction/intervention assessment of posture and laparoscopic skills. Subjective and objective data obtained before and after instruction/intervention were tabulated and analyzed for statistical significance. All 7 subjects completed the study. Subjects showed improved ergonomics and improved ability to complete FLS™ as well as subjective improvement in overall posture. The Alexander technique training program resulted in a significant improvement in posture. Improved surgical ergonomics, endurance and posture decrease surgical fatigue and the incidence of repetitive stress injuries to laparoscopic surgeons. Further studies of the influence of the Alexander technique on surgical posture, minimally invasive surgery ergonomics and open surgical techniques are warranted to explore and validate the benefits for surgeons. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

The effect of three different surgical techniques for colon anastomosis on regional postoperative microperfusion: Laser Doppler Flowmetry study in pigs.

PubMed

Kaska, Milan; Blazej, Slavomir; Turek, Zdenek; Ryska, Ales; Jegorov, Boris; Radochova, Vera; Bezouska, Jan; Paral, Jiri

2018-01-01

The optimal surgical approach to reconnecting bowel ends safely after resection is of great importance. This project is focused on assessment of the perianastomotic microcirculation quality in the short postoperative period when using three different anastomosis techniques in experimental animal. The experimental study involved 27 young female domestic pigs divided into three subgroups of 9 animals according to each surgical method of anastomosis construction in the sigmoid colon region: by manual suture, by stapler, or by gluing. Blood microcirculation in the anastomosis region was monitored using Laser Doppler Flowmetry (LDF). Anastomosis healing was evaluated by macroscopic and histological examination. Evaluation of the microcirculation in the anastomosis region showed the smallest decrease in perfusion values in animals reconstructed by suturing (Δ= -38.01%). A significantly more profound drop was observed postoperatively after stapling or gluing (Δ= -52.42% and Δ= -59.53%, respectively). All performed anastomoses healed without any signs of tissue and function pathology. Sewing, stapling, and gluing techniques for bowel anastomosis each have a different effect on regional microcirculation during 120 min. postoperatively. Nevertheless, the final results of anastomosis healing were found without of any pathology in all experimental animals managed by above mentioned anastomotic techniques.

Techniques for shuttle trajectory optimization

NASA Technical Reports Server (NTRS)

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

1973-01-01

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

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.

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

PubMed Central

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

2013-01-01

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

Trends in the Surgical Correction of Gynecomastia

PubMed Central

Brown, Rodger H.; Chang, Daniel K.; Siy, Richard; Friedman, Jeffrey

2015-01-01

Gynecomastia refers to the enlargement of the male breast due to a proliferation of ductal, stromal, and/or fatty tissue. Although it is a common condition affecting up to 65% of men, not all cases require surgical intervention. Contemporary surgical techniques in the treatment of gynecomastia have become increasingly less invasive with the advent of liposuction and its variants, including power-assisted and ultrasound-assisted liposuction. These techniques, however, have been largely limited in their inability to address significant skin excess and ptosis. For mild to moderate gynecomastia, newer techniques using arthroscopic morcellation and endoscopic techniques promise to address the fibrous component, while minimizing scar burden by utilizing liposuction incisions. Nevertheless, direct excision through periareolar incisions remains a mainstay in treatment algorithms for its simplicity and avoidance of additional instrumentation. This is particularly true for more severe cases of gynecomastia requiring skin resection. In the most severe cases with significant skin redundancy and ptosis, breast amputation with free nipple grafting remains an effective option. Surgical treatment should be individualized to each patient, combining techniques to provide adequate resection and optimize aesthetic results. PMID:26528088

A Literature Review of Renal Surgical Anatomy and Surgical Strategies for Partial Nephrectomy

PubMed Central

Klatte, Tobias; Ficarra, Vincenzo; Gratzke, Christian; Kaouk, Jihad; Kutikov, Alexander; Macchi, Veronica; Mottrie, Alexandre; Porpiglia, Francesco; Porter, James; Rogers, Craig G.; Russo, Paul; Thompson, R. Houston; Uzzo, Robert G.; Wood, Christopher G.; Gill, Inderbir S.

2016-01-01

Context A detailed understanding of renal surgical anatomy is necessary to optimize preoperative planning and operative technique and provide a basis for improved outcomes. Objective To evaluate the literature regarding pertinent surgical anatomy of the kidney and related structures, nephrometry scoring systems, and current surgical strategies for partial nephrectomy (PN). Evidence acquisition A literature review was conducted. Evidence synthesis Surgical renal anatomy fundamentally impacts PN surgery. The renal artery divides into anterior and posterior divisions, from which approximately five segmental terminal arteries originate. The renal veins are not terminal. Variations in the vascular and lymphatic channels are common; thus, concurrent lymphadenectomy is not routinely indicated during PN for cT1 renal masses in the setting of clinically negative lymph nodes. Renal-protocol contrast-enhanced computed tomography or magnetic resonance imaging is used for standard imaging. Anatomy-based nephrometry scoring systems allow standardized academic reporting of tumor characteristics and predict PN outcomes (complications, remnant function, possibly histology). Anatomy-based novel surgical approaches may reduce ischemic time during PN; these include early unclamping, segmental clamping, tumor-specific clamping (zero ischemia), and unclamped PN. Cancer cure after PN relies on complete resection, which can be achieved by thin margins. Post-PN renal function is impacted by kidney quality, remnant quantity, and ischemia type and duration. Conclusions Surgical renal anatomy underpins imaging, nephrometry scoring systems, and vascular control techniques that reduce global renal ischemia and may impact post-PN function. A contemporary ideal PN excises the tumor with a thin negative margin, delicately secures the tumor bed to maximize vascularized remnant parenchyma, and minimizes global ischemia to the renal remnant with minimal complications. Patient summary In this report

A Literature Review of Renal Surgical Anatomy and Surgical Strategies for Partial Nephrectomy.

PubMed

Klatte, Tobias; Ficarra, Vincenzo; Gratzke, Christian; Kaouk, Jihad; Kutikov, Alexander; Macchi, Veronica; Mottrie, Alexandre; Porpiglia, Francesco; Porter, James; Rogers, Craig G; Russo, Paul; Thompson, R Houston; Uzzo, Robert G; Wood, Christopher G; Gill, Inderbir S

2015-12-01

A detailed understanding of renal surgical anatomy is necessary to optimize preoperative planning and operative technique and provide a basis for improved outcomes. To evaluate the literature regarding pertinent surgical anatomy of the kidney and related structures, nephrometry scoring systems, and current surgical strategies for partial nephrectomy (PN). A literature review was conducted. Surgical renal anatomy fundamentally impacts PN surgery. The renal artery divides into anterior and posterior divisions, from which approximately five segmental terminal arteries originate. The renal veins are not terminal. Variations in the vascular and lymphatic channels are common; thus, concurrent lymphadenectomy is not routinely indicated during PN for cT1 renal masses in the setting of clinically negative lymph nodes. Renal-protocol contrast-enhanced computed tomography or magnetic resonance imaging is used for standard imaging. Anatomy-based nephrometry scoring systems allow standardized academic reporting of tumor characteristics and predict PN outcomes (complications, remnant function, possibly histology). Anatomy-based novel surgical approaches may reduce ischemic time during PN; these include early unclamping, segmental clamping, tumor-specific clamping (zero ischemia), and unclamped PN. Cancer cure after PN relies on complete resection, which can be achieved by thin margins. Post-PN renal function is impacted by kidney quality, remnant quantity, and ischemia type and duration. Surgical renal anatomy underpins imaging, nephrometry scoring systems, and vascular control techniques that reduce global renal ischemia and may impact post-PN function. A contemporary ideal PN excises the tumor with a thin negative margin, delicately secures the tumor bed to maximize vascularized remnant parenchyma, and minimizes global ischemia to the renal remnant with minimal complications. In this report we review renal surgical anatomy. Renal mass imaging allows detailed delineation of the

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

PubMed

Tebbetts, John B

2006-12-01

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

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

PubMed

Tebbetts, John B

2002-01-01

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

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

PubMed

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

2010-11-11

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

Optimal resources for children's surgical care in the United States.

PubMed

2014-03-01

In summary, the Task Force does understand that change is difficult and, in the circumstance of the US health care environment, quite complex. Having acknowledged this, the Task Force firmly believes that if optimal resource standards are clear, providers will act in the best interests of their patients, infants, and children undergoing surgery in this circumstance. We intend to provide evidence to this point, to define optimal resources, and to facilitate this process. The hope and the underlying intent of these recommendations is to insure that every infant and child undergoing a surgical procedure in the United States will receive his or her care in an environment that offers all of the facilities, equipment, and, most especially, access to the professional providers who have the appropriate background and training to provide optimal care. This must be done while balancing the issues of access, staff, and the need to improve the value proposition. The Task Force is unanimous in its intent to advocate for this agenda.

A new plastic surgical technique for adult congenital webbed penis

PubMed Central

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

2012-01-01

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

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.

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

NASA Astrophysics Data System (ADS)

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

2017-11-01

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

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

PubMed

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

2016-10-01

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

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". Copyright © 2016 Elsevier Inc. All rights reserved.

[Wound microbial sampling methods in surgical practice, imprint techniques].

PubMed

Chovanec, Z; Veverková, L; Votava, M; Svoboda, J; Peštál, A; Doležel, J; Jedlička, V; Veselý, M; Wechsler, J; Čapov, I

2012-12-01

The wound is a damage of tissue. The process of healing is influenced by many systemic and local factors. The most crucial and the most discussed local factor of wound healing is infection. Surgical site infection in the wound is caused by micro-organisms. This information is known for many years, however the conditions leading to an infection occurrence have not been sufficiently described yet. Correct sampling technique, correct storage, transportation, evaluation, and valid interpretation of these data are very important in clinical practice. There are many methods for microbiological sampling, but the best one has not been yet identified and validated. We aim to discuss the problem with the focus on the imprint technique.

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

PubMed

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

2017-01-01

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

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

PubMed Central

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

2017-01-01

Introduction: There are various treatment modalities to remove the black patches of melanin pigmentation. The aim of the study is to clinically compare the diode laser ablation and surgical stripping technique for gingival depigmentation and to evaluate their effect on the histological changes in melanocyte activity. Materials and Methods: A total of 40 sites of 20 patients with bilateral melanin hyperpigmentation were treated with the surgical stripping and diode laser ablation technique. Change in Hedin index score, change in area of pigmentation using image analyzing software, pain perception, patient preference of treatment were recorded. All 40 sites were selected for immunohistochemical analysis using HMB-45 immunohistochemical marker. Results: At 12 months post-operative visit, in all sites, repigmentation was observed with different grades of Hedin index. Paired t-test, analysis of variance, and Chi-square tests were used for statistical analysis. Repigmentation in surgical stripping is significantly lesser compared to laser ablation. Lesser numbers of melanocytes were found on immunohistological examination at 12 months postoperatively. Comparison for patient preference and pain indices give statistically significant values for diode laser techniques. Conclusion: Gingival hyperpigmentation is effectively managed by diode laser ablation technique and surgical stripping method. In this study, surgical stripping technique found to be better compared to diode laser ablation. PMID:28539864

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

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.

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

PubMed

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

2015-05-01

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

J-tube technique for double-j stent insertion during laparoscopic upper urinary tract surgical procedures.

PubMed

Kim, Hyung Suk; Lee, Byung Ki; Jung, Jin-Woo; Lee, Jung Keun; Byun, Seok-Soo; Lee, Sang Eun; Jeong, Chang Wook

2014-11-01

Double-J stent insertion has been generally performed during laparoscopic upper urinary tract (UUT) surgical procedures to prevent transient urinary tract obstruction and postoperative flank pain from ureteral edema and blood clots. Several restrictive conditions that make this procedure difficult and time consuming, however, include the coiled distal ends of the flexible Double-J stent and the limited bending angle of the laparoscopic instruments. To overcome these limitations, we devised a Double-J stent insertion method using the new J-tube technique. Between July 2011 and May 2013, Double-J stents were inserted using the J-tube technique in 33 patients who underwent a laparoscopic UUT surgical procedure by a single surgeon. The mean stent placement time was 4.8±2.7 minutes, and there were no intraoperative complications. In conclusion, the J-tube technique is a safe and time-saving method for Double-J stent insertion during laparoscopic surgical procedures.

[Comparative clinical study of 2 surgical techniques for trapeziometacarpal osteoarthritis].

PubMed

Martínez-Martínez, F; García-Hortelano, S; García-Paños, J P; Moreno-Fernández, J M; Martín-Ferrero, M Á

2016-01-01

In trapeziometacarpal osteoarthritis (or rhizarthrosis), there is great controversy over the surgical technique to choose: simple trapeziectomy, resection-interposition arthroplasty, interposition arthroplasty suspension-or arthroplasty with implant or prosthesis. These latter 2 are the most used without consensus in the literature on the technique to choose and without sufficient comparative studies. The objective is to compare the 2 techniques most used today: suspension-interposition arthroplasty and arthroplasty with prosthesis. A prospective study was conducted on 15 patients diagnosed with grade 2-3 rhizarthrosis treated with interposition arthroplasty-suspension (group 1) and 15 with prosthesis (group 2) showing clinical outcomes, advantages and disadvantages of each. The study variables were the visual analogue scale (VAS), the DASH questionnaire, the grip strength, the strength of end to end and end-lateral clamp, the joint balance adduction-abduction and preemption-retropositioning, and the opposition. The 2 groups are from 2 different hospitals operated on by a hand surgeon from the Hand Unit. The follow-up time for all patients included in the study was 12 months. The VAS, DASH and grip strength at 12 months did not show significant differences. As regards the strength of end to end and end-lateral clamp, group 2 showed the highest values in all follow-up periods with statistically significant differences. Patient selection and surgical experience is essential, given the satisfactory results of both techniques. Arthroplasty prosthesis is reserved for grades 2 and 3, middle-aged patients, good trapezium architecture, and experienced surgeons. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

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

PubMed

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

2013-07-01

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

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

PubMed

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

2017-06-01

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

Minimally invasive reduction and fixation of displaced calcaneal fractures: surgical technique and radiographic analysis.

PubMed

Arastu, Mateen; Sheehan, Brendan; Buckley, Richard

2014-03-01

The optimal treatment of calcaneal fractures is controversial. A specific subgroup of healthy patients has good outcomes with open reduction and internal fixation using an extensile lateral approach. However, there are many patients who do not fit into this category. Consequently, they are either denied surgical intervention or put at significant risk of developing complications as a result of open surgical intervention. Minimally invasive reduction and fixation (MIRF) of calcaneal fractures can restore the height, width, length and shape of the hindfoot in addition to restoring the orientation of the posterior facet of the calcaneus (Böhler's angle). We present a series of 31 patients treated with minimally invasive reduction and fixation technique using threaded K wires and Steinmann pins as an alternative treatment method in patients who are not suitable for open reduction and internal fixation. The mean time to surgery from injury was six days (range one to ten days). The mean duration of surgery was 35 minutes (range 11-52 minutes). The mean followup was 14.9 months (range of seven to 30 months). The mean change in Böhler's angle and length of the calcaneus from intra-operative fixation to final followup were 18.7° and 4.7 mm, respectively. The complication rate was low and there was one case of a superficial wound infection and no cases of deep infection or peroneal impingement in this series. The MIRF technique with the use of threaded K wires has not been previously described in the literature. In our experience, the operative time is short and can be safely performed even in the presence of extensive soft tissue swelling in the immediate period following injury. The infection risk is low and calcaneal morphology was improved and maintained in terms of Böhler's angle. This technique is suitable to be considered in patients who have significant medical co-morbidities (smokers, diabetics, peripheral vascular disease) and in those patients who are

Surgical technique for reconstruction of the nasal septum: the pericranial flap.

PubMed

Paloma, V; Samper, A; Cervera-Paz, F J

2000-01-01

We describe a new technique for the surgical reconstruction of large-sized anterior septal perforations based on the pericranial flap. The technique requires a standard open rhinoplasty combined with a pericranial flap harvested after a bicoronal approach and tunnelled to the nasal cavity. We present the case of a man with complete destruction of the nasal septum as a result of chronic cocaine abuse. Surgery resulted in a permanent and complete closure of the perforation. The main advantage of this technique is the use of well-vascularized autogenous tissue and the minimal donor site morbidity. This technique provides a new method to close large nasal perforations. Copyright 2000 John Wiley & Sons, Inc. Head Neck 22: 90-94, 2000.

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.

A New Technique in Surgical Management of the Giant Cerebral Hydatid Cysts.

PubMed

Aydin, Mehmet Dumlu; Karaavci, Nuh Cagri; Akyuz, Mehmet Emin; Sahin, Mehmet Hakan; Zeynal, Mete; Kanat, Ayhan; Altinors, Mehmet Nur

2018-05-01

In hydatid disease, the central nervous system is affected approximately in 2% to 3% of patients. Surgical management in these patients is important. To develop a surgical technique to avoid the formation of great volume of cavity after hydatid cyst removal and prevent complications associated with brain collapse and cortical convolution. In 2 patients, hydatid cysts were delivered by this new technique. A balloon filled with 150 cc of sterile air/distilled water was placed in the cavity until the balloon filled the entire cavity. Air/distilled water evacuation was continued at a rate of 20 cc/d and, after a week, eventually, the balloons were removed RESULTS:: All cysts were delivered without rupture. Neurologic outcomes were good. No complications were observed related to usage of the system such as balloon rupture, evacuation problems, and infection. The authors believe that the balloon insertion technique may be a useful method to prevent brain collapse, cortical convolution, and complications associated with this condition. Further technical refinements of the system are needed for better results.

Pinhole Surgical Technique for treatment of marginal tissue recession: A case series.

PubMed

Reddy, Saravanan Sampoornam Pape

2017-01-01

The field of periodontal plastic surgery is always a subject of fascination for periodontists, and the importance of pink esthetics is gaining its pace. Preservation of what is existing is more important than its replacement. The same principle also applies to soft-tissue esthetic procedures thereby the concept of minimal surgical invasion came into existence. This article presents a series of five cases with 18 recession sites which were treated with a minimally invasive Pinhole Surgical Technique which resulted in overall root coverage of 96.7% after 6-month follow-up with minimal complications.

Traumatic laryngotracheal stenosis--an alternative surgical technique.

PubMed

Syal, Rajan; Tyagi, Isha; Goyal, Amit

2006-02-01

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

Contemporary Medical and Surgical Management of X-linked Hypophosphatemic Rickets.

PubMed

Sharkey, Melinda S; Grunseich, Karl; Carpenter, Thomas O

2015-07-01

X-linked hypophosphatemia is an inheritable disorder of renal phosphate wasting that clinically manifests with rachitic bone pathology. X-linked hypophosphatemia is frequently misdiagnosed and mismanaged. Optimized medical therapy is the cornerstone of treatment. Even with ideal medical management, progressive bony deformity may develop in some children and adults. Medical treatment is paramount to the success of orthopaedic surgical procedures in both children and adults with X-linked hypophosphatemia. Successful correction of complex, multiapical bone deformities found in patients with X-linked hypophosphatemia is possible with careful surgical planning and exacting surgical technique. Multiple methods of deformity correction are used, including acute and gradual correction. Treatment of some pediatric bony deformity with guided growth techniques may be possible. Copyright 2015 by the American Academy of Orthopaedic Surgeons.

[Propensity score comparison of the various radical surgical techniques for high-risk prostate cancer].

PubMed

Busch, J; Gonzalgo, M; Leva, N; Ferrari, M; Friedersdorff, F; Hinz, S; Kempkensteffen, C; Miller, K; Magheli, A

2015-01-01

The optimal surgical treatment of patients with a high risk prostate cancer (PCa) in terms of radical prostatectomy (RP) is still controversial: open retropubic RP (RRP), laparoscopic RP (LRP), or robot-assisted (RARP). We aimed to investigate the influence of the different surgical techniques on pathologic outcome and biochemical recurrence. A total of 805 patients with a high risk PCa (PSA >20 ng/mL, Gleason Score ≥8, or clinical stage ≥cT2c) were included. A comparison of 407 RRP patients with 398 minimally invasive cases (LRP+RARP) revealed significant confounders. Therefore all 110 RARP cases were propensity score (PS) matched 1:1 with LRP and RRP patients. PS included age, clinical stage, preoperative PSA, biopsy Gleason score, surgeon's experience and application of a nerve sparing technique. Comparison of overall survival (OS) and recurrence-free survival (RFS) was done with the log rank test. Predictors of RFS were analyzed by means of Cox regression models. Within the post-matching cohort of 330 patients a pathologic Gleason score < 7, = 7 and > 7 was found in 1.8, 55.5 and 42.7% for RARP, in 8.2, 36.4, 55.5% for LRP and in 0, 60.9 and 39.1% for RRP (p=0.004 for RARP vs. LRP and p=0.398 for RARP vs. RRP). Differences in histopathologic stages were not statistically significant. The overall positive surgical margin rate (PSM) as well as PSM for ≥ pT3 were not different. PSM among patients with pT2 was found in 15.7, 14.0 and 20.0% for RARP, LRP and RRP (statistically not significant). The respective mean 3-year RFS rates were 41.4, 77.9, 54.1% (p<0.0001 for RARP vs. LRP and p=0.686 for RARP vs. RRP). The mean 3-year OS was calculated as 95.4, 98.1 and 100% respectively (statistically not significant). RARP for patients with a high risk PCa reveals similar pathologic and oncologic outcomes compared with LRP and RRP. © Georg Thieme Verlag KG Stuttgart · New York.

Surgical Management of the Constricted or Obliterated Vagina.

PubMed

Gebhart, John B; Schmitt, Jennifer J

2016-08-01

Management of the constricted or obliterated vagina demands an understanding and recognition of the potential etiologies leading to this presentation. A thorough and comprehensive medical and surgical review is required to arrive at an accurate diagnosis, which then will guide medical or surgical intervention. It is paramount to recognize when underlying medical conditions are contributing to these conditions and to begin medical therapy; failure to do so will often yield suboptimal results. When these conditions arise after surgical interventions, compensatory surgical techniques that correct upper and lower vaginal strictures or obliteration include incision through the stricture, vaginal advancement, Z-plasty, skin grafts, perineal flaps, and abdominal flaps and grafts. Postoperative surveillance and dilation are critical to optimize long-term success.

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

PubMed

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

2017-05-01

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

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

PubMed

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

2015-06-19

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

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.

Optimal surgical management of severe tricuspid regurgitation in cardiac transplant patients.

PubMed

Filsoufi, Farzan; Salzberg, Sacha P; Anderson, Curtis A; Couper, Gregory S; Cohn, Lawrence H; Adams, David H

2006-03-01

Severe tricuspid regurgitation (TR) with signs of right-sided heart failure is rare after orthotopic heart transplantation (OHT). In some instances, this condition will require surgical correction using reconstructive surgery or prosthetic valve replacement. Repair techniques of atrioventricular valves are now well described. However, the results of the different surgical procedures in this setting have not been widely reported and may depend on the type of valvular dysfunction and lesions present. Herein we report our experience in a group of patients requiring surgical correction of symptomatic severe TR after OHT. We reviewed our transplant experience during the period from July 1992 to July 1999 (n = 138 cardiac transplants). Eight patients (5.8%) developed symptomatic severe TR requiring surgical correction after a mean duration of 21 months after OHT. Patients were divided into 2 groups based on the mechanism of regurgitation using Carpentier's functional classification. In Group 1 (n = 4), the mechanism of tricuspid regurgitation was Carpentier's Type I, secondary to annular dilation. In Group 2 (n = 4) the mechanism of TR was leaflet prolapse (Type II), due to chordal rupture after biopsy injury. Initially, tricuspid valve integrity was surgically restored in all 8 patients with either valve repair (n = 6) or replacement (n = 2). In Group 1, 2 patients underwent valve repair using a ring annuloplasty and 2 patients underwent valve replacement with a bioprosthetic valve (n = 1) or pulmonary allograft (n = 1). In Group 2, all patients underwent valve repair using a variety of techniques in combination with tricuspid annuloplasty. During the follow-up period, 3 of the 6 (50%) primary repairs (1 patient in Group 1 and 2 in Group 2) failed and required replacement with a bioprosthesis at 8 days, 14 days and 4 years, respectively. The pulmonary allograft failed secondary to valvular stenosis and was replaced with a bioprosthesis after 10 months. Overall, no

Surgical Updates in the Treatment of Pelvic Organ Prolapse.

PubMed

Geynisman-Tan, Julia; Kenton, Kimberly

2017-04-28

Pelvic organ prolapse affects approximately 8% of women, and the demand for pelvic organ prolapse surgery is expected to increase by nearly 50% over the next 40 years. The surgical techniques used to correct pelvic organ prolapse have evolved over the last 10 years, with multiple well-designed studies addressing the risks, outcomes, reoperation rates, and optimal surgical approaches. Here we review the most recent evidence on the route of access, concomitant procedures, and synthetic materials for augmenting the repair. Ultimately, this review highlights that there is no optimal method for correcting pelvic organ prolapse and that the risks, benefits, and approaches should be discussed in a patient-centered, goal-oriented approach to decision-making.

The effect of patient selection and surgical technique on the results of Conserve® Plus hip resurfacing--3.5- to 14-year follow-up.

PubMed

Amstutz, Harlan C; Takamura, Karren M; Le Duff, Michel J

2011-04-01

The results of metal-on-metal hip Conserve® Plus resurfacings with up to 14 years of follow-up with and without risk factors of small component size and/or large femoral defects were compared as performed with either first- or second-generation surgical techniques. There was a 99.7% survivorship at ten years for ideal hips (large components and small defects) and a 95.3% survivorship for hips with risk factors optimized technique has measurably improved durability in patients with risk factors at the 8-year mark. The lessons learned can help offset the observed learning curve of resurfacing. Copyright © 2011 Elsevier Inc. All rights reserved.

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.

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

NASA Astrophysics Data System (ADS)

Sun, Jingyuan; Yan, Zhiyuan; Du, Zhijiang

2017-06-01

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

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

PubMed

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

2010-02-01

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

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

PubMed

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

2013-09-01

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

Technique Developed for Optimizing Traveling-Wave Tubes

NASA Technical Reports Server (NTRS)

Wilson, Jeffrey D.

1999-01-01

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

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deters, Katherine A.; Brown, Richard S.; Boyd, James W.

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 wasmore » 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.« less

Endoscopic Evacuation of Basal Ganglia Hematoma: Surgical Technique, Outcome, and Learning Curve.

PubMed

Ma, Lichao; Hou, Yuanzheng; Zhu, Ruyuan; Chen, Xiaolei

2017-05-01

Minimally invasive endoscopic hematoma evacuation is a promising treatment option for intracerebral hemorrhage. However, the technique still needs improvement. We report our clinical experience of using this technique to evacuate deep-seated basal ganglia hematomas. The frontal approach was used in most patients. The preoperative and postoperative hematoma volumes, Glasgow Coma Scale, hematoma evacuation rate, 30-day mortality, and long-term outcome defined by the modified Rankin Scale were analyzed retrospectively. The surgical duration per milliliter of clot (DPM) was calculated. The learning curve for this technique was determined based on the relation between the DPM and evacuation rate per the number of cases experienced. A total of 24 patients were enrolled. The evacuation rate was 87% ± 10%. The average Glasgow Coma Scale score recovered from 8 to 13 after surgery. Twenty-one patients had follow-up data. The follow-up time was 13 ± 6 months. The 30-day mortality after surgery was zero. Forty-eight percent of patients (10/21) achieved a favorable outcome. The DPM (P = 0.92) and evacuation rate (P = 0.64) did not change substantially with the number of cases experienced. Endoscopic port surgery for hematoma evacuation via the frontal approach is a safe surgical option for deep-seated basal ganglia hematomas. This technique is minimally invasive and may be helpful to provide better long-term outcomes for selected patients. For neurosurgeons, the learning curve for this technique is steep, which implies that the skills needed for our technique can be easily acquired. Copyright © 2017 Elsevier Inc. All rights reserved.

Prospective study of wound infections in Mohs micrographic surgery using clean surgical technique in the absence of prophylactic antibiotics.

PubMed

Rogers, Heather D; Desciak, Edward B; Marcus, Rebecca P; Wang, Shuang; MacKay-Wiggan, Julian; Eliezri, Yehuda D

2010-11-01

Mohs micrographic surgery (MMS) has a low rate of surgical site infection (SSI) without the use of prophylactic antibiotics. In the studies to date, there has been variation in the steps taken by each surgeon to prevent SSIs but in all cases sterile technique was used during wound reconstruction. We sought to evaluate the rate of SSIs among patients undergoing MMS with the use of clean surgical technique for all steps of MMS including wound reconstruction in the absence of prophylactic antibiotics. We prospectively evaluated 1000 patients undergoing MMS using clean surgical technique for SSIs. Clean surgical technique includes the use of clean surgical gloves and towels and a single pack of sterile instruments for all steps including wound reconstruction. There were 11 SSIs among 1000 patients with 1204 tumors, with an overall rate of infection of 0.91% (95% confidence interval 0.38%-1.45%). Three of the 11 infections were complications of hematomas. Four of the 11 infections occurred in flap closures, which had the highest rate of SSIs of 2.67% (4/150). The study was a prospective, single-institution uncontrolled study. To our knowledge, this is the first study to examine the rate of SSIs with the use of clean surgical technique, in the absence of antibiotic prophylaxis, for all steps of MMS including wound reconstruction. Our rate of SSIs of 0.91% is exceedingly low, underscoring the overall safety of MMS and its performance in the outpatient setting without the use of antibiotic prophylaxis or sterile technique. Copyright © 2010 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

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.

Surgical Techniques. Second Edition. Teacher Edition.

ERIC Educational Resources Information Center

Bushey, Vicki; And Others

This instructor's manual contains 18 units of instruction for a course on surgical technology designed to include the entry-level competencies students need as a surgical technologist. Each unit includes some or all of the following basic components of a unit of instruction: objective sheet, suggested activities for the teacher, assignment sheets…

Surgical Treatment of Intestinal Endometriosis: Outcomes of Three Different Techniques.

PubMed

Bray-Beraldo, Fernando; Pereira, Ana Maria Gomes; Gazzo, Cláudia; Santos, Marcelo Protásio; Lopes, Reginaldo Guedes Coelho

2018-06-27

 To outline the demographic and clinical characteristics of patients with deep intestinal endometriosis submitted to surgical treatment at a tertiary referral center with a multidisciplinary team, and correlate those characteristics with the surgical procedures performed and operative complications.  A prospective cohort from February 2012 to November 2016 of 32 women with deep intestinal endometriosis operations. The variables analyzed were: age; obesity; preoperative symptoms (dysmenorrhea, dyspareunia, acyclic pain, dyschezia, infertility, urinary symptoms, constipation and intestinal bleeding); previous surgery for endometriosis; Enzian classification; size of the intestinal lesion; and surgical complications.  The mean age was 37.75 (±5.72) years. A total of 7 patients (22%) had a prior history of endometriosis. The mean of the largest diameter of the intestinal lesions identified intraoperatively was of 28.12 mm (±14.29 mm). In the Enzian classification, there was a predominance of lesions of the rectum and sigmoid, comprising 30 cases (94%). There were no statistically significant associations between the predictor variables and the outcome complications, even after the multiple logistic regression analysis. Regarding the size of the lesion, there was also no significant correlation with the outcome complications ( p  = 0.18; 95% confidence interval [95%CI]:0.94-1.44); however, there was a positive association between grade 3 of the Enzia classification and the more extensive surgical techniques: segmental intestinal resection and rectosigmoidectomy, with a prevalence risk of 4.4 ( p  < 0.001; 95%CI:1.60-12.09).  The studied sample consisted of highly symptomatic women. A high prevalence of deep infiltrative endometriosis lesions was found located in the rectum and sigmoid region, and their size correlated directly with the extent of the surgical resection performed. Thieme Revinter Publicações Ltda Rio de Janeiro, Brazil.

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

NASA Astrophysics Data System (ADS)

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

2009-08-01

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

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. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Optimization of white matter tractography for pre-surgical planning and image-guided surgery.

PubMed

Arfanakis, Konstantinos; Gui, Minzhi; Lazar, Mariana

2006-01-01

Accurate localization of white matter fiber tracts in relation to brain tumors is a goal of critical importance to the neurosurgical community. White matter fiber tractography by means of diffusion tensor magnetic resonance imaging (DTI) is the only non-invasive method that can provide estimates of brain connectivity. However, conventional tractography methods are based on data acquisition techniques that suffer from image distortions and artifacts. Thus, a large percentage of white matter fiber bundles are distorted, and/or terminated early, while others are completely undetected. This severely limits the potential of fiber tractography in pre-surgical planning and image-guided surgery. In contrast, Turboprop-DTI is a technique that provides images with significantly fewer distortions and artifacts than conventional DTI data acquisition methods. The purpose of this study was to evaluate fiber tracking results obtained from Turboprop-DTI data. It was demonstrated that Turboprop may be a more appropriate DTI data acquisition technique for tracing white matter fibers than conventional DTI methods, especially in applications such as pre-surgical planning and image-guided surgery.

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. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

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

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.

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

PubMed

Aziz, Faisal

2015-01-01

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

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

PubMed

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

2012-06-01

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

Antegrade subinguinal sclerotization with temporary clamping of the spermatic cord: a new surgical technique for varicocele.

PubMed

Mancini, Mario; Carmignani, Luca; Agarwal, Ashok; Ciociola, Francesco; Pasqualotto, Fabio; Castiglioni, M Fabrizio; Piediferro, Guido; Colpi, Giovanni M

2011-01-01

The purpose of our study was to evaluate the duration, effectiveness, and complications associated with a new operating technique for varicocele, using a subinguinal surgical approach and antegrade sclerotization of the spermatic veins. A total of 756 varicocele patients who came under our care for infertility underwent surgical treatment with our technique. The diagnosis was based on clinical examination and confirmed by color-Doppler ultrasound of the spermatic cord. Only patients with continuous basal reflux inside the left spermatic vein detected in orthostatism underwent operation. The Colpi technique was used, which consists of a subinguinal incision with suspension of the spermatic cord; cord clamping for 8-10 minutes using two elastic bands; and injection of 1.5-3 mL of sclerosing agent during induced ischemia without any intraoperative radiological control. The average operating time was 25 minutes (range: 18-45 minutes). At the 3-month postoperative follow-up, there were 15 cases of persistent reflux (1.9%), 6 cases of hydrocele requiring surgical correction (0.7%), and 50 cases of fibrotic sequelae of penile lymphangiitis (6.6%). The new technique was more effective than the previous ones, with the exception of the microsurgical technique, which, however, takes 2-3 times longer to perform. The only significant complication was superficial single-vessel lymphangiitis of the penis, which resolved within 3 months with no apparent consequences. In conclusion, this new operating technique for varicocele is simpler to perform and may be effective compared with other techniques. Copyright © 2011 Elsevier Inc. All rights reserved.

Safe surgical technique for associated acetabular fractures

PubMed Central

2013-01-01

Associated acetabular fractures are challenging injuries to manage. The complex surgical approaches and the technical difficulty in achieving anatomical reduction imply that the learning curve to achieve high-quality care of patients with such challenging injuries is extremely steep. This first article in the Journal’s “Safe Surgical Technique” section presents the standard surgical care, in conjunction with intraoperative tips and tricks, for the safe management of all subgroups of associated acetabular fractures. PMID:23414782

Haemorrhoidectomy as a one-day surgical procedure: modified Ferguson technique.

PubMed

Kosorok, P; Mlakar, B

2005-04-01

Modification of Ferguson haemorrhoidectomy had been started because it was easier to ligate the haemorrhoidal pedicle with a rubber band instead of using the stitch. There is no need to use a retractor for such a procedure as it would cause discomfort to the patient when only infiltrative anaesthesia for one or two haemorrhoidal complexes was given. In the period from 1994 to 1999, we performed 398 haemorrhoidectomies as a one-day surgical procedure under local infiltrative anaesthesia. The examination follow-ups of the patients were performed and medical charts were reviewed. Early postoperative complications were rare: haemorrhage occurred in 1.8%, urine retention in 0.5%, high temperature in 1.3% and temporary incontinence in 0.3%. Overall, 28 patients (7%) had additional treatment for residual haemorrhoid problems 5-10 years after the primary haemorrhoidectomy was performed. We believe that our modified technique is a welcome alternative to the one-day surgical practice.

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.

New technique to fabricate an immediate surgical obturator restoring the defect in original anatomical form.

PubMed

Patil, Pravinkumar G

2011-08-01

The presence of oral cancer can necessitate the surgical removal of all or part of the maxilla, leaving the patient with a defect compromising the oral cavity's integrity and function. The immediate postoperative restoration of esthetics, deglutition, and speech shortens recovery time in the hospital and expedites the patient's return to the community as a functioning member. This article describes a simple technique to fabricate an immediate surgical obturator by restoring the patient's original dentition and facial and palatal tissue form. An immediate obturator fabricated with this technique supports soft tissues after surgery and minimizes scar contracture and disfigurement and thus may have a positive effect on the patient's psychology. © 2011 by The American College of Prosthodontists.

Modeling hospital surgical delivery process design using system simulation: optimizing patient flow and bed capacity as an illustration.

PubMed

Kumar, Sameer

2011-01-01

It is increasingly recognized that hospital operation is an intricate system with limited resources and many interacting sources of both positive and negative feedback. The purpose of this study is to design a surgical delivery process in a county hospital in the U.S where patient flow through a surgical ward is optimized. The system simulation modeling is used to address questions of capacity planning, throughput management and interacting resources which constitute the constantly changing complexity that characterizes designing a contemporary surgical delivery process in a hospital. The steps in building a system simulation model is demonstrated using an example of building a county hospital in a small city in the US. It is used to illustrate a modular system simulation modeling of patient surgery process flows. The system simulation model development will enable planners and designers how they can build in overall efficiencies in a healthcare facility through optimal bed capacity for peak patient flow of emergency and routine patients.

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

PubMed Central

Dalbayrak, Sedat; Yaman, Onur; Yılmaz, Mesut

2013-01-01

Context: Treatment of Hangman's fractures is still controversial. Hangman's fractures Type II and IIA are usually treated with surgical procedures. Aim: This study aims at describing the Neurospinal Academy (NSA) technique as an attempt to achieve an approximation of the fracture line to the axis body, which may be used for Type II and IIA patients with severe displacement and angulation. Settings and Design: NSA technique both pars or pedicle screws are placed bicortically to ensure that anterior surface of C2 vertebral body will be crossed 1-2 mm. A rod is prepared in suitable length and curve to connect the two screws. For placing the rod, sufficient amount of bone is resected from the C2 spinous process. C2 vertebral body is pulled back by means of the screws that crossed the anterior surface of C2 vertebral body. Materials and Methods: Hangman II and IIA patient are treated with NSA technique. Result: Angulated and tilted C2 vertebral body was pulled back and approximated to posterior elements. Conclusions: In Hangman's fractures Type II and IIA with severe vertebral body and pedicle displacement, NSA technique is an effective and reliable treatment alternative for the approximation of posterior elements to the C2 vertebral body, which is tilted, angulated, and dislocated. PMID:24744563

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

PubMed

Dalbayrak, Sedat; Yaman, Onur; Yılmaz, Mesut

2013-07-01

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

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

PubMed

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

2013-06-19

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

Computer-based desktop system for surgical videotape editing.

PubMed

Vincent-Hamelin, E; Sarmiento, J M; de la Puente, J M; Vicente, M

1997-05-01

The educational role of surgical video presentations should be optimized by linking surgical images to graphic evaluation of indications, techniques, and results. We describe a PC-based video production system for personal editing of surgical tapes, according to the objectives of each presentation. The hardware requirement is a personal computer (100 MHz processor, 1-Gb hard disk, 16 Mb RAM) with a PC-to-TV/video transfer card plugged into a slot. Computer-generated numerical data, texts, and graphics are transformed into analog signals displayed on TV/video. A Genlock interface (a special interface card) synchronizes digital and analog signals, to overlay surgical images to electronic illustrations. The presentation is stored as digital information or recorded on a tape. The proliferation of multimedia tools is leading us to adapt presentations to the objectives of lectures and to integrate conceptual analyses with dynamic image-based information. We describe a system that handles both digital and analog signals, production being recorded on a tape. Movies may be managed in a digital environment, with either an "on-line" or "off-line" approach. System requirements are high, but handling a single device optimizes editing without incurring such complexity that management becomes impractical to surgeons. Our experience suggests that computerized editing allows linking surgical scientific and didactic messages on a single communication medium, either a videotape or a CD-ROM.

Financial impact of surgical technique in the treatment of acute appendicitis in children.

PubMed

Litz, Cristen; Danielson, Paul D; Gould, Jay; Chandler, Nicole M

2013-09-01

Appendicitis is the most common emergent problem encountered by pediatric surgeons. Driven by improved cosmetic outcomes, many surgeons are offering pediatric patients single-incision laparoscopic appendectomy. We sought to investigate the financial impact of different surgical approaches to appendectomy. A retrospective study of patients with acute appendicitis undergoing appendectomy from February 2010 to September 2011 was conducted. Based on surgeon preference, patients underwent open appendectomy (OA), laparoscopic appendectomy (LA), or single-incision laparoscopic appendectomy (SILA). Demographic information, surgical outcomes, surgical supply costs, and total direct costs were recorded. A total of 465 patients underwent appendectomy during the study. The mean age of all patients was 11.2 years (range, 1 to 18 years). There were no conversions in the LA or SILA groups. There was a significant difference among surgical technique in regard to surgical supply costs (OA $159 vs. LA $650 vs. SILA $814, P < 0.01) and total direct costs (OA $2129 vs. LA $2624 vs. SILA $2991, P < 0.01). In our institution, both multiport laparoscopic and SILA carry higher costs when compared with OA, largely as a result of the cost of disposable instrumentation. Cost efficiency should be considered by surgeons when undertaking a minimally invasive approach to appendectomy.

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

PubMed Central

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

2015-01-01

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

"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

2017-07-01

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

THD Doppler procedure for hemorrhoids: the surgical technique.

PubMed

Ratto, C

2014-03-01

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

Kyphectomy in meningomyelocele children: surgical technique, risk analysis, and improvement of kyphosis.

PubMed

de Amoreira Gepp, Ricardo; Quiroga, Marco Rolando Sainz; Gomes, Cícero Ricardo; de Araújo, Hugo José

2013-07-01

Kyphosis is a major complication of spina bifida, causing skin ulcers and osteomyelitis. This study examined the clinical and surgical characteristics of eight patients who underwent surgery, as well as improvement of their postoperative kyphosis angulations. The authors reviewed eight cases submitted to surgery between 2006 and 2010. Surgical intervention was indicated for osteomyelitis and recurrent ulcers at the curvature apex. Osteotomies and spine stabilization were performed. The patients' clinical characteristics were analyzed, as were the surgical techniques employed, variables of surgical complications, and angle range of the kyphosis deformity postcorrection. There were no deaths. The average age at the time of surgery was 11 years old. The level of neurological injury was T10 in four patients and T12 in four. Average amount of bleeding during surgery was 1,442 ml, (range, 340 to 3,200 ml). Improvement of kyphosis angle was evident in all patients. The average difference between preoperative and postoperative kyphosis angle was 63.2. Surgery performed by a multidisciplinary team minimizes risks. Despite the high number of complications published in the literature, the results found in this study were excellent with regards to improving kyphosis angle, as well as facilitating rehabilitation and daily care of children.

Gynecomastia associated with herniated nipples: an optimal surgical approach.

PubMed

Jaiswal, Rohit; Pu, Lee L Q

2012-04-01

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

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.

Optimization of freeform surfaces using intelligent deformation techniques for LED applications

NASA Astrophysics Data System (ADS)

Isaac, Annie Shalom; Neumann, Cornelius

2018-04-01

For many years, optical designers have great interests in designing efficient optimization algorithms to bring significant improvement to their initial design. However, the optimization is limited due to a large number of parameters present in the Non-uniform Rationaly b-Spline Surfaces. This limitation was overcome by an indirect technique known as optimization using freeform deformation (FFD). In this approach, the optical surface is placed inside a cubical grid. The vertices of this grid are modified, which deforms the underlying optical surface during the optimization. One of the challenges in this technique is the selection of appropriate vertices of the cubical grid. This is because these vertices share no relationship with the optical performance. When irrelevant vertices are selected, the computational complexity increases. Moreover, the surfaces created by them are not always feasible to manufacture, which is the same problem faced in any optimization technique while creating freeform surfaces. Therefore, this research addresses these two important issues and provides feasible design techniques to solve them. Finally, the proposed techniques are validated using two different illumination examples: street lighting lens and stop lamp for automobiles.

Coracoid bypass procedure: surgical technique for coracoclavicular reconstruction with coracoid insufficiency.

PubMed

Virk, Mandeep S; Lederman, Evan; Stevens, Christopher; Romeo, Anthony A

2017-04-01

Failed acromioclavicular (AC) joint reconstruction secondary to a coracoid fracture or insufficiency of the coracoid is an uncommon but challenging clinical situation. We describe a surgical technique of revision coracoclavicular (CC) reconstruction, the coracoid bypass procedure, and report short-term results with this technique in 3 patients. In the coracoid bypass procedure, reconstruction of the CC ligaments is performed by passing a tendon graft through a surgically created bone tunnel in the scapular body (inferior to the base of the coracoid) and then fixing the graft around the clavicle or through bone tunnels in the clavicle. Three patients treated with this technique were retrospectively reviewed. AC joint reconstruction performed for a traumatic AC joint separation failed in the 3 patients reported in this series. The previous procedures were an anatomic CC reconstruction in 2 patients and a modified Weaver-Dunn procedure in 1 patient. The coracoid fractures were detected postoperatively, and the mean interval from the index surgery to the coracoid bypass procedure was 8 months. The patients were a mean age of 44 years, and average follow-up was 21 months. At the last follow-up, all 3 patients were pain free, with full range of shoulder motion, preserved CC distance, and a stable AC joint. The coracoid bypass procedure is a treatment option for CC joint reconstruction during revision AC joint surgery in the setting of a coracoid fracture or coracoid insufficiency. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Endonasal laser-assisted microscopic dacryocystorhinostomy: surgical technique and follow-up results.

PubMed

Farzampour, Shahrokh; Fayazzadeh, Ehsan; Mikaniki, Ebrahim

2010-01-01

Endonasal dacryocystorhinostomy is known as an increasingly attractive and effective approach for the surgical treatment of nasal duct obstruction with minimal complications and best cosmetic consequences. In a relatively large-scale case-series study over a 5-year period, we describe the surgical technique and 12-month follow-up results of microscopic laser dacryocystorhinostomy with particular regard to the effect of various pre-/postoperational factors (ie, patients' sex, age, symptoms chronicity, previous interventions, duration of silicone intubation) on the surgical outcome. A total of 162 cases in 151 patients with chronic epiphora, mucocele, or recurrent episodes of dacryocystitis were included in the study. Endonasal laser dacryocystorhinostomy was performed using a surgical microscope with transcanalicular lacrimal sac illumination. The laser types used were potassium-titanyl-phosphate and neodymium:yttrium-aluminum-garnet for ablation of nasal mucosa and application to bone, respectively. Patients were evaluated 6 months and 1 year later. Data were analyzed by chi(2) tests. There were no major complications during or after the operations. Complete cure occurred in 89.5% (after 6 months) and 74.2% (after 1 year) of the cases. Anatomical patency was shown by lacrimal system irrigation with fluorescein in 81.5% of the cases after the 12-month follow-up. It was found that patients younger than 55 years, with symptoms lasting less than 1 year, and without history of nasal problems, had significantly higher surgical success rates (P < .05). Moreover, rates of failure were significantly lower in cases whose canaliculi were intubated for 5 to 6 months (P < .05). Endonasal microscopic laser dacryocystorhinostomy is a safe and minimally invasive procedure with reasonable results. It has many advantages over external or other conventional approaches. Successful results could be further enhanced by more wisely selecting the patients and by silicone extubation after

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shah, Chirag; Vicini, Frank A., E-mail: fvicini@beaumont.edu

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 withmore » 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.« less

A critical analysis of the surgical outcomes for the treatment of Peyronie’s disease

PubMed Central

Mandava, Sree H.; Trost, Landon W.; Hellstrom, Wayne J.G.

2013-01-01

Peyronie’s disease (PD) is a relatively common condition, which can impair sexual function and result in emotional and psychological distress. Despite an abundance of minimally invasive treatments, few have confirmed efficacy for improving penile curvature and function. Surgical therapies include many different techniques and are reserved for patients with stable disease of ⩾12 months’ duration. We searched PubMed for all articles from 1990 to the present relating to the surgical management of PD. Preference was given to recent articles, larger series, and those comparing various techniques and/or materials. Outcomes were subsequently analysed and organised by surgical technique and the graft material used. Available surgical techniques include plication/corporoplasty procedures, incision and grafting (I&G), and placing a penile prosthesis with or without adjunctive procedures. Although several surgical algorithms have been reported, in general, plication/corporoplasty procedures are reserved for patients with adequate erectile function, simple curvatures of <60°, and with no deformities (hour-glass, hinge). I&G are reserved for complex curvatures of >60° and those with deformities. Penile prostheses are indicated for combined erectile dysfunction and PD. Overall outcomes show high rates of improved curvature and patient satisfaction, with mildly decreased erectile function with both plication and the I&G procedure (I&G >plication) and decreases in penile length (plication >I&G). Surgical management of PD remains an excellent treatment option for patients with penile curvature precluding or impairing sexual activity. Surgical algorithms are available to assist treating clinicians in appropriately stratifying surgical candidates. Additional research is needed to identify optimal surgical techniques and materials based on patient and disease characteristics. PMID:26558094

Bovine thoracoscopy: surgical technique and normal anatomy.

PubMed

Scharner, Doreen; Dorn, Katja; Brehm, Walter

2014-01-01

To describe a surgical technique for thoracoscopy and report visible anatomy within the thoracic cavity of standing cattle. Prospective study. Adult clinically healthy Holstein-Friesian cows (n = 15). Each cow had four thoracoscopic examinations. Initially, the left hemithorax was examined after passive lung collapse, then again 24 hours later after CO2 insufflation. The right hemithorax was examined 24 hours later after passive lung collapse and again 24 hours later after CO2 insufflation. CO2 insufflation did not significantly improve visibility within the pleural space. Collapsed lung, aorta, esophagus, diaphragm, and azygos vein were readily viewed; however, the pericardial region was not consistently visible. Minor laceration of the lung occurred in 1 cow with adhesions, otherwise there were no intra- or postoperative complications. All cows recovered without signs of discomfort. No local swelling or emphysema occurred at the portals. Thoracoscopy can be safely performed on healthy standing cattle. © Copyright 2013 by The American College of Veterinary Surgeons.

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

PubMed

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

2015-09-01

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. 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. 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. 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.

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

A surgical technique to expand the operative corridor for supracerebellar infratentorial approaches: technical note.

PubMed

Rey-Dios, Roberto; Cohen-Gadol, Aaron A

2013-10-01

The supracerebellar infratentorial approach is a commonly used route in neurosurgery. It provides a narrow and deep corridor to the dorsal midbrain and pineal region. The authors describe a surgical technique to expand the operative corridor and the surgeon's working angles during this approach. Thirteen cases of patients who underwent resection of their lesions using this extended approach were reviewed. During their suboccipital craniotomy, additional bone over the transverse sinus (paramedian approach) and the confluence of the sinuses (midline approach) were removed. Two sutures (tentorial stay sutures) were anchored to the tentorium anterior to the transverse sinus and tension was applied. A video narrated by the senior author describes the details of technique. This additional bone removal and tentorial stay sutures led to gentle elevation of the tentorium and partial mobilization of the dural venous sinuses superiorly. This technique enhanced operative viewing through improved illumination and expanded working angles for microsurgical instruments while minimizing the need for fixed retractors and extensive cerebellar retraction. All patients underwent satisfactory removal of their lesions. No patient suffered from any related complication. The use of stay sutures anchored on the tentorium is a simple and effective technique that expands the surgical corridor during supracerebellar infratentorial approaches.

Anterior mandibular apical base augmentation in the surgical orthodontic treatment of mandibular retrusion.

PubMed

Brusati, R; Giannì, A B

2005-12-01

The authors describe a surgical technique alternative to traditional pre-surgical orthodontics in order to increase the apical base in mandibular retrusion (class II, division I). This subapical osteotomy, optimizing inferior incisal axis without dental extractions and a long orthodontic treatment, associated to genioplasty permits to obtain an ideal labio-dento-mental morphology. This procedure avoids in some cases the need of a mandibular advancement and, if necessary, it reduces his entity with obvious advantages.

[Female stress urinary incontinence. Surgical repair with pubovaginal sling techniques].

PubMed

Escribano Patiño, Gregorio; Hernández Fernández, Carlos; Subirá Ríos, David; Castaño González, Irene; Moralejo Gárate, Mercedes; Martinez Salamanca, Juan Ignacio

2002-11-01

To review the treatment of female stress urinary incontinence by new systems of tension-free urethral sling TVT type (Tension free vaginal tape) or IVS (intravaginal slingplasty), and the bone anchoring trasvaginal sling procedure Infast. We describe the surgical techniques of the various procedures and perform a bibliographic review on the topic. The pubovaginal sling has become the gold standard in the treatment of female stress urinary incontinence, mainly if there is sphincter intrinsic dysfunction. The concept of tension free medium urethra support has been the most important contribution, that questions the classification of incontinence in types I, II and III, because the pubocervical tension free sling can correct all three. Tension free urethral sling techniques have demonstrated to be effective, minimally invasive with a low complication rate, easily reproducible, and with good continence results in the mid-term.

Optimization techniques applied to passive measures for in-orbit spacecraft survivability

NASA Technical Reports Server (NTRS)

Mog, Robert A.; Price, D. Marvin

1987-01-01

Optimization techniques applied to passive measures for in-orbit spacecraft survivability, is a six-month study, designed to evaluate the effectiveness of the geometric programming (GP) optimization technique in determining the optimal design of a meteoroid and space debris protection system for the Space Station Core Module configuration. Geometric Programming was found to be superior to other methods in that it provided maximum protection from impact problems at the lowest weight and cost.

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

PubMed

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

2016-07-01

To provide a comprehensive overview of the basic science rationale, surgical technique, and clinical outcomes of 1-step cartilage repair technique used as a treatment strategy for cartilage defects. A systematic review was performed in the main medical databases to evaluate the several studies concerning 1-step procedures for cartilage repair. The characteristics of cell-seed scaffolds, behavior of cells seeded into scaffolds, and surgical techniques were also discussed. Clinical outcomes and quality of repaired tissue were assessed using several standardized outcome assessment tools, magnetic resonance imaging scans, and biopsy histology. One-step cartilage repair could be divided into 2 types: chondrocyte-matrix complex (CMC) and autologous matrix-induced chondrogenesis (AMIC), both of which allow a simplified surgical approach. Studies with Level IV evidence have shown that 1-step cartilage repair techniques could significantly relieve symptoms and improve functional assessment (P < .05, compared with preoperative evaluation) at short-term follow-up. Furthermore, magnetic resonance imaging showed that 76% cases in all included case series showed at least 75% defect coverage in each lesion, and 3 studies clearly showed hyaline-like cartilage tissue in biopsy tissues by second-look arthroscopy. The 1-step cartilage repair technique, with its potential for effective, homogeneous distribution of chondrocytes and multipotent stem cells on the surface of the cartilage defect, is able to regenerate hyaline-like cartilage tissue, and it could be applied to cartilage repair by arthroscopy. Level IV, systematic review of Level II and IV studies. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

CAD/CAM-produced surgical guides: Optimizing the treatment workflow.

PubMed

Neugebauer, J; Kistler, F; Kistler, S; Züdorf, G; Freyer, D; Ritter, L; Dreiseidler, T; Kusch, J; Zöller, J E

2011-01-01

The increased availability of devices for 3D radiological diagnosis allows the more frequent use of CAD/CAM-produced surgical guides for implant placement. The conventional workflow requires a complex logistic chain which is time-consuming and costly. In a pilot study, the workflow of directly milled surgical guides was evaluated. These surgical guides were designed based on the fusion of an optical impression and the radiological data. The clinical use showed that the surgical guides could be accurately placed on the residual dentition without tipping movements. The conventional surgical guides were used as a control for the manual check of the deviation of the implant axis. The direct transfer of the digital planning data allows the fabrication of surgical guides in an external center without the need of physical transport, which reduces the logistic effort and expense of the central fabrication of surgical guides.

Surgical technique for management of isolated lenticular coloboma with high corneal astigmatism.

PubMed

Singh, Simar Rajan; Yangzes, Sonam; Gupta, Rohit; Ram, Jagat

2018-04-01

We describe a surgical technique for the correction of isolated congenital lenticular coloboma associated with high corneal astigmatism. Transscleral fixation of the capsular bag with a single eyelet Cionni capsular tension ring was followed by in-the-bag implantation of a toric intraocular lens (IOL). This lead to complete correction of the lenticular defect and perfect alignment of the toric lens. In this case, the child attained an unaided distance visual acuity of 20/30 following amblyopia therapy and a well-aligned toric IOL at 12 months of follow-up. This technique can be used in cases with concomitant lenticular coloboma and significant corneal astigmatism.

Surgical technique for management of isolated lenticular coloboma with high corneal astigmatism

PubMed Central

Singh, Simar Rajan; Yangzes, Sonam; Gupta, Rohit; Ram, Jagat

2018-01-01

We describe a surgical technique for the correction of isolated congenital lenticular coloboma associated with high corneal astigmatism. Transscleral fixation of the capsular bag with a single eyelet Cionni capsular tension ring was followed by in-the-bag implantation of a toric intraocular lens (IOL). This lead to complete correction of the lenticular defect and perfect alignment of the toric lens. In this case, the child attained an unaided distance visual acuity of 20/30 following amblyopia therapy and a well-aligned toric IOL at 12 months of follow-up. This technique can be used in cases with concomitant lenticular coloboma and significant corneal astigmatism. PMID:29582820

Intraocular biopsy using special forceps: a new instrument and refined surgical technique.

PubMed

Akgul, Harun; Otterbach, Friedrich; Bornfeld, Norbert; Jurklies, Bernhard

2011-01-01

The aim was to investigate the Essen biopsy forceps as a new instrument and surgical approach for biopsy of intraocular tumours. Biopsy is indicated for assessment of any uncertain intraocular process or confirmation for presumed diagnosis before treatment. There is increasing interest for further genetic and immunocytological information in order to characterise the neoplasm, especially grading and prognosis of micrometastasis in uveal melanoma. The authors have developed a new surgical technique using special intraocular biopsy forceps. Twenty patients with uncertain intraocular subretinal tumour underwent biopsies carried out using the special Essen biopsy forceps. Biopsies were obtained through sutureless 23-gauge three-port vitrectomy. A small retinotomy tumour specimen was taken by the forceps branches. For further processing, the specimens were flushed out into a sterile tube and then sent to pathologists. The prebioptical tumour had a mean thickness of 3.48 mm (1.1 to 9.8 mm). In all cases (n=20) biopsies (0.3-2.1 mm in size) were obtained, in 19 cases (95%) allowing precise histological and immunohistochemical typing of the lesions following cytoblock embedding. Uveal melanoma was diagnosed in 50% (n=10), choroidal metastasis in 15% (n=3) and choroidal naevus in 15% (n=3); other diagnoses (n=3) included choroidal haemangioma, B cell lymphoma and old subretinal haemorrhage. Apart from three patients with temporary punctual bleeding on the surface, there were no intra- and postoperative complications. Biopsy using special forceps is a promising new approach and precise surgical procedure. Especially for small intraocular tumours, this technique has the advantage in providing enough tissue for improved histological examination and presenting a low risk for complications.

Optimization of segmented thermoelectric generator using Taguchi and ANOVA techniques.

PubMed

Kishore, Ravi Anant; Sanghadasa, Mohan; Priya, Shashank

2017-12-01

Recent studies have demonstrated that segmented thermoelectric generators (TEGs) can operate over large thermal gradient and thus provide better performance (reported efficiency up to 11%) as compared to traditional TEGs, comprising of single thermoelectric (TE) material. However, segmented TEGs are still in early stages of development due to the inherent complexity in their design optimization and manufacturability. In this study, we demonstrate physics based numerical techniques along with Analysis of variance (ANOVA) and Taguchi optimization method for optimizing the performance of segmented TEGs. We have considered comprehensive set of design parameters, such as geometrical dimensions of p-n legs, height of segmentation, hot-side temperature, and load resistance, in order to optimize output power and efficiency of segmented TEGs. Using the state-of-the-art TE material properties and appropriate statistical tools, we provide near-optimum TEG configuration with only 25 experiments as compared to 3125 experiments needed by the conventional optimization methods. The effect of environmental factors on the optimization of segmented TEGs is also studied. Taguchi results are validated against the results obtained using traditional full factorial optimization technique and a TEG configuration for simultaneous optimization of power and efficiency is obtained.

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.

The Michigan Surgical Home and Optimization Program is a scalable model to improve care and reduce costs.

PubMed

Englesbe, Michael J; Grenda, Dane R; Sullivan, June A; Derstine, Brian A; Kenney, Brooke N; Sheetz, Kyle H; Palazzolo, William C; Wang, Nicholas C; Goulson, Rebecca L; Lee, Jay S; Wang, Stewart C

2017-06-01

The Michigan Surgical Home and Optimization Program is a structured, home-based, preoperative training program targeting physical, nutritional, and psychological guidance. The purpose of this study was to determine if participation in this program was associated with reduced hospital duration of stay and health care costs. We conducted a retrospective, single center, cohort study evaluating patients who participated in the Michigan Surgical Home and Optimization Program and subsequently underwent major elective general and thoracic operative care between June 2014 and December 2015. Propensity score matching was used to match program participants to a control group who underwent operative care prior to program implementation. Primary outcome measures were hospital duration of stay and payer costs. Multivariate regression was used to determine the covariate-adjusted effect of program participation. A total of 641 patients participated in the program; 82% were actively engaged in the program, recording physical activity at least 3 times per week for the majority of the program; 182 patients were propensity matched to patients who underwent operative care prior to program implementation. Multivariate analysis demonstrated that participation in the Michigan Surgical Home and Optimization Program was associated with a 31% reduction in hospital duration of stay (P < .001) and 28% lower total costs (P < .001) after adjusting for covariates. A home-based, preoperative training program decreased hospital duration of stay, lowered costs of care, and was well accepted by patients. Further efforts will focus on broader implementation and linking participation to postoperative complications and rigorous patient-reported outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

[Surgical technique for the treatment of the serious acute necrotic pancreatitis in the National Hospital Edgardo Rebagliati Martins].

PubMed

Barreda Cevasco, Luis Alberto; Targarona Modena, Javier; Rodriguez Alegría, César

2002-01-01

A surgical technique for the treatment of severe acute pancreatitis with necrosis is presented as an alternative in the surgical treatment of this pathology; 60 patients underwent a surgery by the author et al. between October 1997 and January 2002, at the National Hospital Edgardo Rebagliati Martins, Lima, Peru. The mortality rate was 25%.

Surgical orthodontics.

PubMed

Strohl, Alexis M; Vitkus, Lauren

2017-08-01

The article reviews some commonly used orthodontic treatments as well as new strategies to assist in the correction of malocclusion. Many techniques are used in conjunction with surgical intervention and are a necessary compliment to orthognathic surgery. Basic knowledge of these practices will aid in the surgeon's ability to adequately treat the patient. Many orthodontists and surgeons are eliminating presurgical orthodontics to adopt a strategy of 'surgery first' orthodontics in orthognathic surgery. This has the benefit of immediate improvement in facial aesthetics and shorter treatment times. The advent of virtual surgical planning has helped facilitate the development of this new paradigm by making surgical planning faster and easier. Furthermore, using intraoperative surgical navigation is improving overall precision and outcomes. A variety of surgical and nonsurgical treatments may be employed in the treatment of malocclusion. It is important to be familiar with all options available and tailor the patient's treatment plan accordingly. Surgery-first orthodontics, intraoperative surgical navigation, virtual surgical planning, and 3D printing are evolving new techniques that are producing shorter treatment times and subsequently improving patient satisfaction without sacrificing long-term stability.

SU-F-T-201: Acceleration of Dose Optimization Process Using Dual-Loop Optimization Technique for Spot Scanning Proton Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirayama, S; Fujimoto, R

Purpose: The purpose was to demonstrate a developed acceleration technique of dose optimization and to investigate its applicability to the optimization process in a treatment planning system (TPS) for proton therapy. Methods: In the developed technique, the dose matrix is divided into two parts, main and halo, based on beam sizes. The boundary of the two parts is varied depending on the beam energy and water equivalent depth by utilizing the beam size as a singular threshold parameter. The optimization is executed with two levels of iterations. In the inner loop, doses from the main part are updated, whereas dosesmore » from the halo part remain constant. In the outer loop, the doses from the halo part are recalculated. We implemented this technique to the optimization process in the TPS and investigated the dependence on the target volume of the speedup effect and applicability to the worst-case optimization (WCO) in benchmarks. Results: We created irradiation plans for various cubic targets and measured the optimization time varying the target volume. The speedup effect was improved as the target volume increased, and the calculation speed increased by a factor of six for a 1000 cm3 target. An IMPT plan for the RTOG benchmark phantom was created in consideration of ±3.5% range uncertainties using the WCO. Beams were irradiated at 0, 45, and 315 degrees. The target’s prescribed dose and OAR’s Dmax were set to 3 Gy and 1.5 Gy, respectively. Using the developed technique, the calculation speed increased by a factor of 1.5. Meanwhile, no significant difference in the calculated DVHs was found before and after incorporating the technique into the WCO. Conclusion: The developed technique could be adapted to the TPS’s optimization. The technique was effective particularly for large target cases.« less

Summary of Optimization Techniques That Can Be Applied to Suspension System Design

DOT National Transportation Integrated Search

1973-03-01

Summaries are presented of the analytic techniques available for three levitated vehicle suspension optimization problems: optimization of passive elements for fixed configuration; optimization of a free passive configuration; optimization of a free ...

A Systematic Review of the Outcomes of Posterolateral Corner Knee Injuries, Part 2: Surgical Treatment of Chronic Injuries.

PubMed

Moulton, Samuel G; Geeslin, Andrew G; LaPrade, Robert F

2016-06-01

There are a variety of reported surgical techniques outcomes of chronic grade III posterolateral corner (PLC) knee injuries. It is unknown if outcomes differ among the various surgical treatments. To systematically review the literature and report subjective and objective outcomes for surgical treatment strategies for chronic grade III PLC injuries to determine the optimal surgical technique. Systematic review; Level of evidence, 4. A systematic review of the literature including Cochrane, PubMed, Medline, and Embase was performed. The following search terms were used: posterolateral corner knee, posterolateral knee, posterolateral instability, multiligament knee, and knee dislocation. Inclusion criteria were outcome studies of surgical treatment for chronic PLC knee injuries with a minimum 2-year follow-up, subjective outcomes, objective outcomes including varus stability, and subgroup data on PLC injuries. Two investigators independently reviewed all abstracts. Accepted definitions of varus stability on examination or stress radiographs, and the need for revision surgery, were used to categorically define success and failure. Fifteen studies with a total of 456 patients were included in this study. The 15 studies included 5 with level 3 evidence and 10 with level 4 evidence. The mean age of the patients in each study ranged from 25.2 to 40 years, the reported mean time to surgery ranged from 5.5 to 52.8 months, and the mean follow-up duration ranged from 2 to 16.3 years. Mean postoperative Lysholm scores ranged from 65.5 to 91.8; mean postoperative International Knee Documentation Committee (IKDC) scores ranged from 62.6 to 86.0. Based on objective stability, there was an overall success rate of 90% and a 10% failure rate of PLC reconstruction. A variety of surgical techniques were reported. Chronic PLC injuries were reconstructed in all studies, and while techniques varied, the surgical management of chronic PLC injuries had a 90% success rate and a 10% failure

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. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Pelvic ring injuries: Surgical management and long-term outcomes

PubMed Central

Halawi, Mohamad J.

2016-01-01

Pelvic ring injuries present a therapeutic challenge to the orthopedic surgeon. Management is based on the patient's physiological status, fracture classification, and associated injuries. Surgical stabilization is indicated in unstable injury patterns and those that fail nonsurgical management. The optimal timing for definitive fixation is not clearly defined, but early stabilization is recommended. Surgical techniques include external fixation, open reduction and internal fixation, and minimally invasive percutaneous osteosynthesis. Special considerations are required for concomitant acetabular fractures, sacral fractures, and those occurring in skeletally immature patients. Long-term outcomes are limited by lack of pelvis-specific outcome measures and burden of associated injuries. PMID:26908968

Surgical Technique of Hemi-Face Transplant: A New Model of Training.

PubMed

Cunico, Caroline; Duarte da Silva, Alfredo Benjamim; Brum, Juliana Sperotto; Robes, Rogério Ribeiro; da Silva Freitas, Renato

2016-05-01

Face transplantation from cadaveric donors is an alternative that has been explored as a way to overcome the disadvantages of reconstructive plastic surgery for patients with severe facial deformities, when its approaches are not able to offer good aesthetic and functional results. In this study, the authors describe the surgical technique of face transplantation in swine, investigating the reproducibility of the methods as an experimental model in transplantation. Seven swines were operated upon. After euthanasia, the left hemifacial area was removed and implanted onto the same location on the same animal from which it was removed. The vascular pedicle was based on the facial artery, the caudal auricular artery, and the external jugular vein. The ventral buccal and dorsal buccal branches of the facial nerve and the transverse facial branch of the auricular nerve were taken into the flap. The mean time of the procedure was 4.5 hours. Differences in vascularization were found as the vessel that provides blood supply to auricular region can be the caudal auricular artery, instead of the temporal artery, as described in the literature. Operative difficulty increases if the animal is more obese. The medical student had training in microsurgical procedures to be able to perform the entire procedure. This study describes an experimental model of face transplantation in swine, providing a good model for training of the surgical technique. The method is reproducible in any setting that offers resources in experimental surgery and microsurgery.

Biomechanical comparison of two surgical techniques for press-fit reconstruction of the posterolateral complex of the knee.

PubMed

Panzica, Martin; Janzik, Janne; Bobrowitsch, Evgenij; Krettek, Christian; Hawi, Nael; Hurschler, Christof; Jagodzinski, Michael

2015-11-01

To date, various surgical techniques to treat posterolateral knee instability have been described. Recent studies recommended an anatomical and isometric reconstruction of the posterolateral corner addressing the key structures, such as lateral collateral ligament (LCL), popliteus tendon (POP) and popliteofibular ligament (PFL). Two clinical established autologous respective local reconstruction methods of the posterolateral complex were tested for knot-bone cylinder press-fit fixation to assess efficacy of each reconstruction technique in comparison to the intact knee. The knot-bone cylinder press-fit fixation for both anatomic and isometric reconstruction techniques of the posterolateral complex shows equal biomechanical stability as the intact posterolateral knee structures. This was a controlled laboratory study. Two surgical techniques (Larson: fibula-based semitendinosus autograft for LCL and PFL reconstruction/Kawano: biceps femoris and iliotibial tract autograft for LCL, PFL and POP reconstruction) with press-fit fixation were used for restoration of posterolateral knee stability. Seven cadaveric knees (66 ± 3.4 years) were tested under three conditions: intact knee, sectioned state and reconstructed knee for each surgical technique. Biomechanical stress tests were performed for every state at 30° and 90° knee flexion for anterior-posterior translation (60 N), internal-external and varus-valgus rotation (5 Nm) at 0°, 30° and 90° using a kinemator (Kuka robot). At 30° and 90° knee flexion, no significant differences between the four knee states were registered for anterior-posterior translation loading. Internal-external and varus-valgus rotational loading showed significantly higher instability for the sectioned state than for the intact or reconstructed posterolateral structures (p < 0.05). There were no significant differences between the intact and reconstructed knee states for internal-external rotation, varus-valgus rotation and anterior

[Surgical issues and outcomes in ischial pressure sores treatment].

PubMed

Voulliaume, D; Grecea, M; Viard, R; Brun, A; Comparin, J-P; Foyatier, J-L

2011-12-01

Ischiatic pressure sores are frequent in spinal cord injury patients, associated with bad prognosis and high recurrence rate. Many surgical techniques were described, including surgical debridement followed by pedicled flap coverage. We aim to propose a practical decision tree for primary or secondary ischial pressure sore treatment. Our series of 48 operated ischial sores with an average follow up of 4 years (range 2 to 8years) is analyzed and compared to previously published reports. Surgical techniques are discussed according to their specific indications. The optimal recurrence rate in published reports about pressure sore treatment is 20%; a rate inferior to 19% is found in our series, showing the equal importance of flap selection and postoperative care and education. Depending on each situation, various available flaps are described and compared: gluteus maximus flap, biceps femoris flap, gracilis flap, tensor fascia lata flap, fasciocutaneous thigh flaps, rectus femoris and vastus lateralis flap, rectus abdominis flap. Specific surgical indications for more extensive wounds are studied: resection arthroplasty of the hip, hip disarticulation, fillet flaps from the leg, microsurgery. Based upon our experience, a decision tree summarizes our proposition of flap selection, depending on the wound size and the patient background. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Influence of Surgical Technique, Performance Status, and Peritonitis Exposure on Surgical Site Infection in Acute Complicated Diverticulitis: A Matched Case-Control Study.

PubMed

Zonta, Sandro; De Martino, Michela; Podetta, Michele; Viganò, Jacopo; Dominioni, Tommaso; Picheo, Roberto; Cobianchi, Lorenzo; Alessiani, Mario; Dionigi, Paolo

2015-10-01

Acute generalized peritonitis secondary to complicated diverticulitis is a life-threatening condition; the standard treatment is surgery. Despite advances in peri-operative care, this condition is accompanied by a high peri-operative complication rate (22%-25%). No definitive evidence is available to recommend a preferred surgical technique in patients with Hinchey stage III/IV disease. A matched case-control study enrolling patients from four surgical units at Italian university hospital was planned to assess the most appropriate surgical treatment on the basis of patient performance status and peritonitis exposure, with the aim of minimizing the surgical site infection (SSI). A series of 1,175 patients undergoing surgery for Hinchey III/IV peritonitis in 2003-2013 were analyzed. Cases (n=145) were selected from among those patients who developed an SSI. control ratio was 1:3. Cases and control groups were matched by age, gender, body mass index, and Hinchey grade. We considered three surgical techniques: T1=Hartman's procedure; T2=sigmoid resection, anastomosis, and ileostomy; and T3=sigmoid resection and anastomosis. Six scoring systems were analyzed to assess performance status; subsequently, patients were divided into low, mild, and high risk (LR, MR, HR) according to the system producing the highest area under the curve. We classified peritonitis exposition as P1=<12 h; P2=12-24 h; P3=>24 h. Univariable and multivariable analyses were performed. The Apgar scoring system defined the risk groups according to performance status. Lowest SSI risk was expected when applying T3 in P1 (OR=0.22), P2 (OR=0.5) for LR and in P1 (OR=0.63) for MR; T2 in P2 (OR=0.5) in LR and in P1 (OR=0.61) in MR; T1 in P3 (OR=0.56) in LR; in P2 (OR=0.63) and P3 (OR=0.54) in MR patients, and in each P subgroup (OR=0.93;0.97;1.01) in HR. Pre-operative assessment based on Apgar scoring system integrated with peritonitis exposure in complicated diverticulitis may offer a ready-to-use tool

Automated optimization techniques for aircraft synthesis

NASA Technical Reports Server (NTRS)

Vanderplaats, G. N.

1976-01-01

Application of numerical optimization techniques to automated conceptual aircraft design is examined. These methods are shown to be a general and efficient way to obtain quantitative information for evaluating alternative new vehicle projects. Fully automated design is compared with traditional point design methods and time and resource requirements for automated design are given. The NASA Ames Research Center aircraft synthesis program (ACSYNT) is described with special attention to calculation of the weight of a vehicle to fly a specified mission. The ACSYNT procedures for automatically obtaining sensitivity of the design (aircraft weight, performance and cost) to various vehicle, mission, and material technology parameters are presented. Examples are used to demonstrate the efficient application of these techniques.

Laparoscopic duodenal-jejunal bypass for the treatment of duodenal obstruction caused by annular pancreas: description of a surgical technique.

PubMed

Zilberstein, Bruno; Sorbello, Mauricio P; Orso, Ivan R B; Cecconello, Ivan

2011-04-01

Annular pancreas is a rare congenital anomaly, which is only surgically treated in symptomatic cases. Surgical treatment consists of bypassing the duodenal transit by gastrojejunal or duodenal-jejunal anastomosis. In the absolute majority of published cases, laparotomy is the most widely used access technique. The aim of this article is to report a case of an annular pancreas and describe the technical steps involved in carrying out a laparoscopic duodenal-jejunal anastomosis, for correction of the duodenal obstruction. The patient's recovery was uneventful; she was discharged on the fourth postoperative day and remained asymptomatic for the 2-year, outpatient follow-up period. Laparoscopic duodenal-jejunal bypass is shown to be feasible and safe, and produce less surgical trauma, when carried out by an experienced surgeon who is duly trained and familiar with the laparoscopic technique.

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

PubMed

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

2015-12-31

Breast cancer is the most common form of cancer and the second leading cause of death amongst women in Europe. Amongst five invasive cancers per 1000 women detected in screening, 2.7 were < 15 mm in diameter; and others reported that over one third of excised breast lesions were clinically occult. The challenge is to accurately locate small non-palpable lesions intraoperatively for optimal therapeutic outcome. A secondary important goal is to remove the smallest amount possible of healthy glandular tissue for optimal cosmesis. Currently the most widely adopted approach (80% in one survey) in guided breast-conserving surgery for excising non-palpable breast lesions is wire-guided localization (WGL). With the clinical setting shifting towards earlier non-palpable breast lesions being detected through screening, we investigated whether the current standard in assisting surgical excision of these lesions, WGL, yields the best therapeutic outcome for women with breast cancer. To assess the therapeutic outcomes of any new form of guided surgical intervention for non-palpable breast lesions against wire-guided localization, the current gold standard. We searched the Cochrane Breast Cancer Group's (CBCG) Specialized Register, MEDLINE (via PubMed), the Cochrane Central Register of Controlled Trials (CENTRAL), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal from the earliest available date up to 30 March 2015. We also handsearched recent conference proceedings and sought information from experts in the field. Two review authors, BC and RJ, independently screened by title and abstract the studies we had identified through the search strategy; when this was inconclusive, they examined the full-text article for inclusion. We resolved any discrepancies regarding eligibility by discussion with a third review author, RA. Three review authors, BC, JW, and RJ, independently extracted data using a standardized data sheet

Comparison of surgical invasiveness between microdiscectomy and three different endoscopic discectomy techniques for lumbar disc herniation.

PubMed

Choi, Kyung-Chul; Shim, Hyeong-Ki; Hwang, Jin-Sup; Shin, Seung Ho; Lee, Dong Chan; Jung, Hwan Hui; Park, Hyeon Ah; Park, Choon-Keun

2018-05-19

Muscle injury is inevitable during surgical exposure of the spine. This study was conducted to investigate paraspinal muscle injury after the following four surgical techniques: microdiscectomy (MD), percutaneous endoscopic lumbar discectomy (PELD), percutaneous endoscopic interlaminar discectomy (PEID), and unilateral biportal endoscopic discectomy (UBED). Eighty patients who underwent the four surgical techniques were prospectively observed. Creatine phosphokinase (CPK) and C-reactive protein (CRP) levels were measured on admission and postoperative days 1, 3, 5, and 7. The CPK ratio was calculated as CPK 1 (postoperative day 1)/CPK 0 (admission). The cross-sectional area (CSA) of the high-intensity lesion in the paraspinal muscle was measured on magnetic resonance images after surgery. The operation time and hospital stay duration were also examined. The clinical outcome was evaluated using the visual analogue scale (VAS) for back and leg pain. The MD group had the significantly highest CPK 1, CPK 3 levels and CPK ratio (p<0.01, p=0.02 and p=0.04, respectively). Serial CRP levels were significantly highest in the MD group (p<0.01). The PELD and PEID groups had lower CRP 1 level than the UBED group. The MD group had the significantly largest CSA (p<0.01). The CSA was larger in the UBED group than in the PELD and PEID groups (p<0.01). The operation time and hospital stay duration were significantly shortest in the PELD group (p<0.01, p<0.01). The MD group had significantly higher VAS scores for back pain on postoperative days 1 and 3 than the other groups (p<0.01 and p=0.02). PELD is the least invasive spinal surgical technique. Copyright © 2018. Published by Elsevier Inc.

Biological intervertebral disc replacement: an in vivo model and comparison of two surgical techniques to approach the rat caudal disc

PubMed Central

Gebhard, Harry; James, Andrew R.; Bowles, Robby D.; Dyke, Jonathan P.; Saleh, Tatianna; Doty, Stephen P.; Bonassar, Lawrence J.; Härtl, Roger

2011-01-01

Study design: Prospective randomized animal study. Objective: To determine a surgical technique for reproducible and functional intervertebral disc replacement in an orthotopic animal model. Methods: The caudal 3/4 intervertebral disc (IVD) of the rat tail was approached by two surgical techniques: blunt dissection, stripping and retracting (Technique 1) or incising and repairing (Technique 2) the dorsal longitudinal tendons. The intervertebral disc was dissected and removed, and then either discarded or reinserted. Outcome measures were perioperative complications, spontaneous tail movement, 7T MRI (T1- and T2-sequences for measurement of disc space height (DSH) and disc hydration). Microcomputed tomographic imaging (micro CT) was additionally performed postmortem. Results: No vascular injuries occurred and no systemic or local infections were observed over the course of 1 month. Tail movements were maintained. With tendon retraction (Technique 1) gross loss of DSH occurred with both discectomy and reinsertion. Tendon division (Technique 2) maintained DSH with IVD reinsertion but not without. The DSH was demonstrated on MRI measurement. A new scoring system to assess IVD appearances was described. Conclusions: The rat tail model, with a tendon dividing surgical technique, can function as an orthotopic animal model for IVD research. Mechanical stimulation is maintained by preserved tail movements. 7T MRI is a feasible modality for longitudinal monitoring for the rat caudal disc. PMID:22956934

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

PubMed

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

2016-02-01

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

Surgical Scar Revision: An Overview

PubMed Central

Garg, Shilpa; Dahiya, Naveen; Gupta, Somesh

2014-01-01

Scar formation is an inevitable consequence of wound healing from either a traumatic or a surgical intervention. The aesthetic appearance of a scar is the most important criteria to judge the surgical outcome. An understanding of the anatomy and wound healing along with experience, meticulous planning and technique can reduce complications and improve the surgical outcome. Scar revision does not erase a scar but helps to make it less noticeable and more acceptable. Both surgical and non-surgical techniques, used either alone or in combination can be used for revising a scar. In planning a scar revision surgeon should decide on when to act and the type of technique to use for scar revision to get an aesthetically pleasing outcome. This review article provides overview of methods applied for facial scar revision. This predominantly covers surgical methods. PMID:24761092

Feedback control for fuel-optimal descents using singular perturbation techniques

NASA Technical Reports Server (NTRS)

Price, D. B.

1984-01-01

In response to rising fuel costs and reduced profit margins for the airline companies, the optimization of the paths flown by transport aircraft has been considered. It was found that application of optimal control theory to the considered problem can result in savings in fuel, time, and direct operating costs. The best solution to the aircraft trajectory problem is an onboard real-time feedback control law. The present paper presents a technique which shows promise of becoming a part of a complete solution. The application of singular perturbation techniques to the problem is discussed, taking into account the benefits and some problems associated with them. A different technique for handling the descent part of a trajectory is also discussed.

Diode-Pumped Laser for Lung-Sparing Surgical Treatment of Malignant Pleural Mesothelioma.

PubMed

Bölükbas, Servet; Biancosino, Christian; Redwan, Bassam; Eberlein, Michael

2017-06-01

Surgical resection represents one of the essential cornerstones in multimodal treatment of malignant pleural mesothelioma. In cases of tumor infiltration of the lung, lung-scarifying procedures such as lobectomies or pneumonectomies might be necessary to achieve macroscopic complete resection. However, this increases the morbidity of the patients because it leads to possible delay of the planned chemotherapy or radiotherapy. Innovative surgical techniques are therefore required to enable salvage of the lung parenchyma and optimization of surgical treatment. Here we report our first experience with a diode-pumped neodymium-doped yttrium aluminium garnet laser for parenchyma-sparing lung resection during surgery for malignant pleural mesothelioma. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

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

PubMed

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

2016-06-01

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

A systematic review on the surgical outcome of preauricular sinus excision techniques.

PubMed

Bruijnzeel, Hanneke; van den Aardweg, Maaike T; Grolman, Wilko; Stegeman, Inge; van der Veen, Erwin L

2016-07-01

Preauricular sinuses are benign congenital malformations of preauricular soft tissues. Complete excision using either sinectomy or supra-auricular approach is advised to prevent recurrence. Reported recurrence varies between 0 and 42%. We evaluated which surgical technique resulted in lowest complication and recurrence rates. PubMed, Embase, Scopus, Web of Science. Two authors appraised studies on directness of evidence and risk of bias. Original data were extracted and pooled when I(2) was smaller than 50%. Results are reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Fourteen high directness of evidence studies were included. Reported complication rates were similar: sinectomy [0-31.4%] and supra-auricular approach (SAA) [0-18.2%]. Pooled recurrence rates showed that sinectomy resulted in significantly (P = .04) more recurrence 5.5% (95% confidence interval [CI] 3.6-8.3%) than SAA 2.2% (95% CI 0.7-7.0). Sinectomy using the microscope resulted in the lowest sinectomy recurrence rates (1.9%). SAA in combination with a Penrose drain resulted in 0% recurrence in revision cases. Drain use resulted in the lowest SAA recurrence rates; however, drain application was not advised due to higher complication rates (frequent wound infection [P = .003] and more [P = .002] and longer [P = .001] compression dressing use). SAA could be the preferable technique for preauricular sinus removal. If despite evidence, sinectomy is elected over SAA, microscope use can further decrease recurrence rates comparable to SAA levels. Level of included evidence (Ib-IV) indicates the need for a prospective study comparing surgical outcomes between techniques. Laryngoscope, 126:1535-1544, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Evaluation of anesthetic technique on surgical site infections (SSIs) at a single institution.

PubMed

Curry, Craig S; Smith, Kahsi A; Allyn, John W

2014-12-01

To determine whether the previously published relationship between anesthetic technique and rate of surgical site infections (SSIs) was influenced by institution specific effects. Retrospective Review of Quality Assurance and Hospital Epidemiology databases. Metropolitan medical center. The records of 7,751 patients who underwent knee or hip joint replacement from 2004 to 2010 were analyzed. Data regarding anesthetic technique, age, ASA status, gender, postoperative temperature, duration of anesthesia and type of surgery were from the department of anesthesiology quality assurance database and SSI cases were identified from the department of epidemiology database. The impact of anesthetic technique and other variables was assessed using bivariate and multivariate techniques. There was no association of anesthetic technique on the rate of SSI. Duration of anesthesia and ASA status were associated with effects on the rate of SSI. The impact of anesthetic technique on SSI following hip and knee replacement surgery may be site specific and using locally gathered quality data may assist in assessing specific institutional impact. Copyright © 2014 Elsevier Inc. All rights reserved.

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

PubMed Central

Fabozzi, Massimiliano; Cirillo, Pia; Corcione, Francesco

2016-01-01

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

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

Caesarean section surgical techniques (CORONIS): a fractional, factorial, unmasked, randomised controlled trial.

PubMed

Abalos, E; Addo, V; Brocklehurst, P; El Sheikh, M; Farrell, B; Gray, S; Hardy, P; Juszczak, E; Mathews, J E; Masood, S Naz; Oyarzun, E; Oyieke, J; Sharma, J B; Spark, P

2013-07-20

Variations exist in the surgical techniques used for caesarean section and many have not been rigorously assessed in randomised controlled trials. We aimed to assess whether any surgical techniques were associated with improved outcomes for women and babies. CORONIS was a pragmatic international 2×2×2×2×2 non-regular fractional, factorial, unmasked, randomised controlled trial that examined five elements of the caesarean section technique in intervention pairs. CORONIS was undertaken at 19 sites in Argentina, Chile, Ghana, India, Kenya, Pakistan, and Sudan. Each site was assigned to three of the five intervention pairs: blunt versus sharp abdominal entry; exteriorisation of the uterus for repair versus intra-abdominal repair; single-layer versus double-layer closure of the uterus; closure versus non-closure of the peritoneum (pelvic and parietal); and chromic catgut versus polyglactin-910 for uterine repair. Pregnant women were eligible if they were to undergo their first or second caesarean section through a planned transverse abdominal incision. Women were randomly assigned by a secure web-based number allocation system to one intervention from each of the three assigned pairs. All investigators, surgeons, and participants were unmasked to treatment allocation. The primary outcome was the composite of death, maternal infectious morbidity, further operative procedures, or blood transfusion (>1 unit) up to the 6-week follow-up visit. Women were analysed in the groups into which they were allocated. The CORONIS Trial is registered with Current Controlled Trials: ISRCTN31089967. Between May 20, 2007, and Dec 31, 2010, 15 935 women were recruited. There were no statistically significant differences within any of the intervention pairs for the primary outcome: blunt versus sharp entry risk ratio 1·03 (95% CI 0·91-1·17), exterior versus intra-abdominal repair 0·96 (0·84-1·08), single-layer versus double-layer closure 0·96 (0·85-1·08), closure versus non

Combined iridocyclectomy and lensectomy surgical technique modified for the removal of an iris cyst in a child.

PubMed

Farpour, Bijan; Browne, Alison; McClellan, BmedscKathyA; Billson, Frank A

2002-01-01

The purpose of this report is to describe a modified surgical iridocyclectomy technique and lensectomy for the removal of a recurrent iris cyst and a cataract in a child. A 3-year-old boy underwent uncomplicated standard iridocyclectomy for the removal of an enlarging congenital epidermal iris cyst. In the postoperative period, the cyst recurred. A second surgical intervention was performed using a modified iridocyclectomy technique. Sclerocorneal dissection of the involved quadrant was performed. After a lensectomy, an additional deep lamellar dissection of the peripheral cornea was undertaken prior to iris cyst removal and pupil reconstruction. This modified two-layered iridocyclectomy technique permits an elegant access to the iris lesion and allows the construction of a two-layered watertight wound, reducing the risk of hypotony and wound ectasia. We believe it also allows a better control of astigmatism and is a safe procedure in the pediatric population, particularly during the amblyogenic period.

Flood frequency analysis using optimization techniques : final report.

DOT National Transportation Integrated Search

1992-10-01

this study consists of three parts. In the first part, a comprehensive investigation was made to find an improved estimation method for the log-Pearson type 3 (LP3) distribution by using optimization techniques. Ninety sets of observed Louisiana floo...

Training femoral neck screw insertion skills to surgical trainees: computer-assisted surgery versus conventional fluoroscopic technique.

PubMed

Nousiainen, Markku T; Omoto, Daniel M; Zingg, Patrick O; Weil, Yoram A; Mardam-Bey, Sami W; Eward, William C

2013-02-01

: Femoral neck fractures are among the most common orthopaedic injuries impacting the health care system. Surgical management of such fractures with cannulated screws is a commonly performed procedure. The acquisition of surgical skills necessary to perform this procedure typically involves learning on real patients with fluoroscopic guidance. This study attempts to determine if a novel computer-navigated training model improves the learning of this basic surgical skill. A multicenter, prospective, randomized, and controlled study was conducted using surgical trainees with no prior experience in surgically managing femoral neck fractures. After a training session, participants underwent a pretest by performing the surgical task (screw placement) on a simulated hip fracture using fluoroscopic guidance. Immediately after, participants were randomized into either undergoing a training session using conventional fluoroscopy or computer-based navigation. Immediate posttest, retention (4 weeks later), and transfer tests were performed. Performance during the tests was determined by radiographic analysis of hardware placement. Screw placement by trainees was ultimately equal to the level of an expert surgeon with either training technique. Participants who trained with computer navigation took fewer attempts to position hardware and used less fluoroscopy time than those trained with fluoroscopy. When those trained with fluoroscopy used computer navigation at the transfer test, less fluoroscopy time and dosage was used. The concurrent augmented feedback provided by computer navigation did not affect the learning of this basic surgical skill in surgical novices. No compromise in learning occurred if the surgical novice trained with one type of technology and transferred to using the other. The findings of this study suggest that computer navigation may be safely used to train surgical novices in a basic procedure. This model avoids using both live patients and harmful

Surgical virtual reality - highlights in developing a high performance surgical haptic device.

PubMed

Custură-Crăciun, D; Cochior, D; Constantinoiu, S; Neagu, C

2013-01-01

Just like simulators are a standard in aviation and aerospace sciences, we expect for surgical simulators to soon become a standard in medical applications. These will correctly instruct future doctors in surgical techniques without there being a need for hands on patient instruction. Using virtual reality by digitally transposing surgical procedures changes surgery in are volutionary manner by offering possibilities for implementing new, much more efficient, learning methods, by allowing the practice of new surgical techniques and by improving surgeon abilities and skills. Perfecting haptic devices has opened the door to a series of opportunities in the fields of research,industry, nuclear science and medicine. Concepts purely theoretical at first, such as telerobotics, telepresence or telerepresentation,have become a practical reality as calculus techniques, telecommunications and haptic devices evolved,virtual reality taking a new leap. In the field of surgery barrier sand controversies still remain, regarding implementation and generalization of surgical virtual simulators. These obstacles remain connected to the high costs of this yet fully sufficiently developed technology, especially in the domain of haptic devices. Celsius.

Cardiaplication: a novel surgical technique for refractory gastroesophageal reflux in the pediatric population.

PubMed

Hill, Sarah J; Pandya, Samir; Clifton, Matthew S; Bhatia, Amina; Wulkan, Mark L

2011-11-01

We encountered 3 patients with severe gastroesophageal reflux disease and tubular stomachs precluding fundoplication. Here, we report the use of an innovative technique, cardiaplication, as an alternative approach for antireflux surgery. Three infants with medically refractory gastroesophageal reflux disease (GERD) were referred for fundoplication. In each case, the patient's anatomy prevented a traditional fundoplication from being performed. A cardiaplication was performed by invaginating the cardia of the stomach at the angle of His and securing the invaginated tissue with interrupted silk suture. The plication tubularized the cardia of the stomach, essentially increasing the intra-abdominal portion of the esophagus and altering the angle of His. The imbrication also creates a flapper valve over the distal esophagus, further limiting potential reflux. The charts for the infants who received cardiaplication were reviewed. Radiographic studies and clinical notes for the presence of persistent reflux were evaluated. Cardiaplication was completed in 3 patients with GERD. All cases were initiated laparoscopically and one was converted to an open procedure secondary to dense adhesive disease. Each child was initiated on feeds between postoperative day 2 and 3. Two of the 3 patients were tolerating goal feeds with-in 2 days. The third patient reached goal feeds on day 16. Postoperative imaging (upper gastrointestinal series [UGI]) was obtained in 2 of the 3 patients. At follow-up (13, 7, and 4 months), all 3 patients are clinically free of symptoms of GERD. Delayed radiographic imaging has confirmed that the patients are no longer refluxing. Based on preliminary findings, cardiaplication appears to be a safe and effective surgical technique for the management of severe GERD in infants. We performed cardiaplication out of necessity; however, after further testing this may prove to be an optimal approach, as it can be performed without disruption of the hiatus.

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

PubMed

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

2016-04-25

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

Optimization Techniques for Design Problems in Selected Areas in WSNs: A Tutorial

PubMed Central

Ibrahim, Ahmed; Alfa, Attahiru

2017-01-01

This paper is intended to serve as an overview of, and mostly a tutorial to illustrate, the optimization techniques used in several different key design aspects that have been considered in the literature of wireless sensor networks (WSNs). It targets the researchers who are new to the mathematical optimization tool, and wish to apply it to WSN design problems. We hence divide the paper into two main parts. One part is dedicated to introduce optimization theory and an overview on some of its techniques that could be helpful in design problem in WSNs. In the second part, we present a number of design aspects that we came across in the WSN literature in which mathematical optimization methods have been used in the design. For each design aspect, a key paper is selected, and for each we explain the formulation techniques and the solution methods implemented. We also provide in-depth analyses and assessments of the problem formulations, the corresponding solution techniques and experimental procedures in some of these papers. The analyses and assessments, which are provided in the form of comments, are meant to reflect the points that we believe should be taken into account when using optimization as a tool for design purposes. PMID:28763039

Optimization Techniques for Design Problems in Selected Areas in WSNs: A Tutorial.

PubMed

Ibrahim, Ahmed; Alfa, Attahiru

2017-08-01

This paper is intended to serve as an overview of, and mostly a tutorial to illustrate, the optimization techniques used in several different key design aspects that have been considered in the literature of wireless sensor networks (WSNs). It targets the researchers who are new to the mathematical optimization tool, and wish to apply it to WSN design problems. We hence divide the paper into two main parts. One part is dedicated to introduce optimization theory and an overview on some of its techniques that could be helpful in design problem in WSNs. In the second part, we present a number of design aspects that we came across in the WSN literature in which mathematical optimization methods have been used in the design. For each design aspect, a key paper is selected, and for each we explain the formulation techniques and the solution methods implemented. We also provide in-depth analyses and assessments of the problem formulations, the corresponding solution techniques and experimental procedures in some of these papers. The analyses and assessments, which are provided in the form of comments, are meant to reflect the points that we believe should be taken into account when using optimization as a tool for design purposes.

The surgical management of chronic subdural hematoma.

PubMed

Ducruet, Andrew F; Grobelny, Bartosz T; Zacharia, Brad E; Hickman, Zachary L; DeRosa, Peter L; Andersen, Kristen N; Anderson, Kristen; Sussman, Eric; Carpenter, Austin; Connolly, E Sander

2012-04-01

Chronic subdural hematoma (cSDH) is an increasingly common neurological disease process. Despite the wide prevalence of cSDH, there remains a lack of consensus regarding numerous aspects of its clinical management. We provide an overview of the epidemiology and pathophysiology of cSDH and discuss several controversial management issues, including the timing of post-operative resumption of anticoagulant medications, the effectiveness of anti-epileptic prophylaxis, protocols for mobilization following evacuation of cSDH, as well as the comparative effectiveness of the various techniques of surgical evacuation. A PubMed search was carried out through October 19, 2010 using the following keywords: "subdural hematoma", "craniotomy", "burr-hole", "management", "anticoagulation", "seizure prophylaxis", "antiplatelet", "mobilization", and "surgical evacuation", alone and in combination. Relevant articles were identified and back-referenced to yield additional papers. A meta-analysis was then performed comparing the efficacy and complications associated with the various methods of cSDH evacuation. There is general agreement that significant coagulopathy should be reversed expeditiously in patients presenting with cSDH. Although protocols for gradual resumption of anti-coagulation for prophylaxis of venous thrombosis may be derived from guidelines for other neurosurgical procedures, further prospective study is necessary to determine the optimal time to restart full-dose anti-coagulation in the setting of recently drained cSDH. There is also conflicting evidence to support seizure prophylaxis in patients with cSDH, although the existing literature supports prophylaxis in patients who are at a higher risk for seizures. The published data regarding surgical technique for cSDH supports primary twist drill craniostomy (TDC) drainage at the bedside for patients who are high-risk surgical candidates with non-septated cSDH and craniotomy as a first-line evacuation technique for c

Karl Ludloff (1864-1945): An Inventive Orthopedic Surgeon, His Work and His Surgical Technique for the Correction of Hallux Valgus.

PubMed

Markatos, Konstantinos; Karaoglanis, Georgios; Damaskos, Christos; Garmpis, Nikolaos; Tsourouflis, Gerasimos; Laios, Konstantinos; Tsoucalas, Gregory

2018-05-01

The purpose of this article is to summarize the work and pioneering achievements in the field of orthopedic surgery of the German orthopedic surgeon Karl Ludloff. Ludloff had an impact in the diagnostics, physical examination, orthopedic imaging, and orthopedic surgical technique of his era. He was a pioneer in the surgical treatment of dysplastic hip, anterior cruciate ligament reconstruction, and hallux valgus. His surgical technique for the correction of hallux valgus, initially stabilized with plaster of Paris, remained unpopular among other orthopedic surgeons for decades. In the 1990s, the advent and use of improved orthopedic materials for fixation attracted the interest of numerous orthopedic surgeons in the Ludloff osteotomy for its ability to correct the deformity in all 3 dimensions, its anatomic outcomes, and its low recurrence rate and patient satisfaction.

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

PubMed

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

2013-03-01

Our present understanding of the effect of robotic surgery and surgical volume on the cost of radical prostatectomy (RP) is limited. Given the increasing pressures placed on healthcare resource utilization, such determinations of healthcare value are becoming increasingly important. Therefore, we performed a study to define the effect of robotic technology and surgical volume on the cost of RP. The state of Maryland mandates that all acute-care hospitals report encounter-level and hospital discharge data to the Health Service Cost Review Commission (HSCRC). The HSCRC was queried for men undergoing RP between 2008 and 2011 (the period during which robot-assisted laparoscopic radical prostatectomy [RALRP] was coded separately). High-volume hospitals were defined as >60 cases per year, and high-volume surgeons were defined as >40 cases per year. Multivariate regression analysis was performed to evaluate whether robotic technique and high surgical volume impacted the cost of RP. There were 1499 patients who underwent RALRP and 2565 who underwent radical retropubic prostatectomy (RRP) during the study period. The total cost for RALRP was higher than for RRP ($14,000 vs 10,100; P<0.001) based primarily on operating room charges and supply charges. Multivariate regression demonstrated that RALRP was associated with a significantly higher cost (β coeff 4.1; P<0.001), even within high-volume hospitals (β coeff 3.3; P<0.001). High-volume surgeons and high-volume hospitals, however, were associated with a significantly lower cost for RP overall. High surgeon volume was associated with lower cost for RALRP and RRP, while high institutional volume was associated with lower cost for RALRP only. High surgical volume was associated with lower cost of RP. Even at high surgical volume, however, the cost of RALRP still exceeded that of RRP. As robotic surgery has come to dominate the healthcare marketplace, strategies to increase the role of high-volume providers may be needed to

Clavicle Malunions: Surgical Treatment and Outcome-a Literature Review.

PubMed

Sidler-Maier, Claudia Christine; Dedy, Nicolas J; Schemitsch, Emil H; McKee, Michael D

2018-02-01

Successful treatment of clavicle malunion represents a major challenge for orthopedic surgeons. The aim of this study was to provide an overview of surgical options for the treatment of clavicle malunions regarding their technical details and clinical results. A comprehensive search of the literature was performed to retrieve articles and conference abstracts regarding the surgical treatment of clavicle malunions. A total of 1873 records were identified and 29 studies were included in the present review, with a total of 103 patients. The majority of the patients (77/103) were treated with an osteotomy and subsequent open reduction internal fixation (ORIF). The next most frequent management choice was debridement, excision, or removal of excess callus or bone ( n  = 19), but other techniques like resection of the clavicle ( n  = 5) or nerve exploration and decompression ( n  = 2) were also reported. The preferred method of fixation was plate fixation ( n  = 53) followed by pin fixation ( n  = 6). The complication rate was low, reported in less than 6% of patients. All of the currently reported surgical techniques to manage symptomatic clavicle malunion have resulted in good clinical outcomes with a low complication rate. Considering biomechanical aspects, correction osteotomy followed by plate fixation seems to be the preferred method. Further studies are needed to compare the various surgical techniques and their specific outcomes in a prospective manner. Nevertheless, this review article can be used as an overview to help choose an optimal operative treatment for patients presenting with a clavicle malunion.

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

PubMed

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

2017-06-01

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

Acute distal biceps tendon rupture--a new surgical technique using a de-tensioning suture to brachialis.

PubMed

Taylor, C J; Bansal, R; Pimpalnerkar, A

2006-09-01

Acute distal biceps rupture is a devastating injury in the young athlete and surgical repair offers the only chance of a full recovery. We report a new surgical technique used in 14 cases of acute distal tendon rupture in which the 'suture anchor technique' and a de-tensioning suture was employed. In this procedure the distal end of the biceps is re-attached to the radial tuberosity using a sliding whip stitch suture and the proximal part of the distal tendon repair attached to the underlying brachialis muscle with absorbable sutures. This restores correct anatomical alignment and isometric pull on the distal tendon and de-tensions the repair in the early post-operative period, allowing early rehabilitation and an early return to activity. In all cases patients regained a full pre-injury level of sporting activity at a mean period of 6.2 months (2-9 months).

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.

A sequential anesthesia technique for surgical repair of unilateral vocal fold paralysis.

PubMed

Rosero, Eric B; Ozayar, Esra; Mau, Ted; Joshi, Girish P

2016-12-01

Thyroplasty with arytenoid adduction, a combined procedure for treatment of unilateral vocal fold paralysis, is typically performed under local anesthesia with sedation to allow for intraoperative voice assessment. However, the need for patient immobility and suppression of laryngeal responses to surgical manipulation can make sedation-analgesia challenging. We describe our first 26 consecutive cases undergoing thyroplasty and arytenoid adduction with a standardized technique consisting of a combination of general anesthesia with tracheal intubation followed by sedation-analgesia. Most patients (69 %) were women, with age of 53 ± 15 years (mean ± SD). Neck surgery was the cause of vocal fold paralysis in 50 % of patients. Initially, general anesthesia was maintained with desflurane and remifentanil with dexmedetomidine added just before tracheal extubation. During the sedation-analgesia phase, patients received infusions of remifentanil and dexmedetomidine. Duration of general anesthesia and sedation-analgesia phases was 162 ± 68.2 and 79 ± 18.3 min, respectively. Mean (SD) wake-up time was 8.0 ± 4.0 min after desflurane discontinuation. Extubation occurred without coughing, bucking, or agitation in 96 % of patients. All the patients were able to phonate appropriately and remained comfortable after emergence. This technique allowed improved surgical conditions with reduced patient discomfort and may be advantageous for other laryngeal and neck surgeries in which intraoperative patient feedback is required.

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.

Material saving by means of CWR technology using optimization techniques

NASA Astrophysics Data System (ADS)

Pérez, Iñaki; Ambrosio, Cristina

2017-10-01

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

The Optimal Surgical Approach for Treatment of Chronic Subdural Hematoma: Questionnaire Assessment of Practice in Iran and Review of Literature.

PubMed

Javadi, Seyed Amir Hossein; Naderi, Fereshteh; Javadi, Amir Mohammad

2015-10-01

Chronic subdural hematoma (CSDH) is a curable entity frequently encountered by neurosurgeons. The present study was conducted to explore expert opinion and common practice in Iran. Besides, a Review of randomized clinical trials in literature was performed. A questionnaire including six questions discussing major aspects of practice on CSDH, with multiple choices was designed. A pilot study was performed for reliability analysis of the questionnaire. A total of 100 neurosurgeons were selected randomly from the members of Iranian Association of Neurological Surgeons. Frequency of answers to each item, differences in response rates and correlation of various categories were analyzed using Chi-square statistics. The mean duration of experience was 15.4 ± 5 years, with a range of 10 to 37 years. The most common initial procedure of choice was burr-hole drainage (64%). At recurrent cases, surgical approach was changed to craniotomy at one-third of those treated initially with burr-hole drainage. The participants believed that surgical technique was predictive of outcome and recurrence. Burr-hole without drainage was used by less expert neurosurgeons (mean 12.5 ± 6), however, burr-hole drainage was the dominant technique at more than 15 years of experience and craniectomy was used only by participants with more than 30 years of experience (10%). Irrigation was used by most of the neurosurgeons (87.5%) in combination with drainage and burr-hole. The majority of participants used flat position at the postoperative period. At the current study, the pattern of management for CSDH was similar to other reports at literature suggesting the burr-hole drainage and irrigation as optimal treatment. Individualized decision-making could be made at challenging cases.

Surgical treatment of male infertility in the era of intracytoplasmic sperm injection – new insights

PubMed Central

Esteves, Sandro C.; Miyaoka, Ricardo; Agarwal, Ashok

2011-01-01

Assisted reproductive technology is an evolving area, and several adjuvant procedures have been created to increase a couple's chance of conceiving. For male infertility, the current challenges are to properly accommodate old and new techniques that are both cost-effective and evidence-based. In this context, urologists are expected to diagnose, counsel, provide medical or surgical treatment whenever possible and/or correctly refer male patients for assisted conception. Urologists are sometimes part of a multiprofessional team in an assisted reproduction unit and are responsible for the above-cited tasks as well as the surgical retrieval of sperm from either the epididymides or testicles. We present a comprehensive review of the surgical treatment options for infertile males, including the perioperative planning and prognostic aspects, with an emphasis on the role of microsurgery in the optimization of treatment results. This review also discusses current techniques for sperm retrieval that are used in association with assisted reproductive technology and includes sperm retrieval success rates according to the technique and the type of azoospermia. New insights are provided with regard to each surgical treatment option in view of the availability of assisted conception to overcome male infertility. PMID:21915501

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

PubMed

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

2017-01-01

The aim of this study was to evaluate the worldwide trends in surgical techniques for esophageal cancer surgery by comparing it to our survey from 2007. In addition, new questions were added for gastroesophageal junction (GEJ) cancer. An international survey on surgery of esophageal and GEJ cancer was performed among surgical members of the International Society for Diseases of the Esophagus, the World Organization for Specialized Studies on Disease of the Esophagus, the International Gastric Cancer Association. Also, surgeons from personal networks were contacted. The participants filled out a web based questionnaire about surgical strategies for esophageal and gastroesophageal cancer. The overall response rate was 478/1147 (42%). The respondents represented 49 different countries and 6 different continents. The annual cumulative number of esophageal and gastric resections per surgeon was low (≤11) in 11%, medium (11-21) in 17%, and high (≥21) in 72% of respondents. In a subgroup analysis of esophageal surgeons the number of high volume surgeons increased from 45 to 54% over the past 7 years. The preferred lymph node dissection was two-field in 86%. A gastric conduit was the preferred method of reconstruction in 95%. In 2014, the preferred approach to esophagectomy was minimally invasive transthoracic in 43%, compared with 14% in 2007. In minimally invasive transthoracic esophagectomy the cervical anastomosis was favored in 54% of respondents in 2014 compared with 87% in 2007. The preferred technique of construction of the cervical anastomosis was hand-sewn in 64% and stapled in 36%, whereas the thoracic anastomosis was stapled in 77% and hand-sewn in 23%. The preferred surgical approach for Siewert type 1 tumors (5-1 cm proximal of the GEJ) was esophagectomy in 93% of respondents, whereas 6% favored gastrectomy and 3% combined a distal esophagectomy with a proximal gastrectomy. For Siewert type 2 tumors (1-2 cm from the GEJ) an extended gastrectomy was

Novel optimization technique of isolated microgrid with hydrogen energy storage.

PubMed

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

2018-01-01

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

Novel optimization technique of isolated microgrid with hydrogen energy storage

PubMed Central

Abdelghany, Hazem; Eteiba, Mahmoud

2018-01-01

This paper presents a novel optimization technique for energy management studies of an isolated microgrid. The system is supplied by various Distributed Energy Resources (DERs), Diesel Generator (DG), a Wind Turbine Generator (WTG), Photovoltaic (PV) arrays and supported by fuel cell/electrolyzer Hydrogen storage system for short term storage. Multi-objective optimization is used through non-dominated sorting genetic algorithm to suit the load requirements under the given constraints. A novel multi-objective flower pollination algorithm is utilized to check the results. The Pros and cons of the two optimization techniques are compared and evaluated. An isolated microgrid is modelled using MATLAB software package, dispatch of active/reactive power, optimal load flow analysis with slack bus selection are carried out to be able to minimize fuel cost and line losses under realistic constraints. The performance of the system is studied and analyzed during both summer and winter conditions and three case studies are presented for each condition. The modified IEEE 15 bus system is used to validate the proposed algorithm. PMID:29466433

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

NASA Astrophysics Data System (ADS)

Mayergoyz, I.; Tyagi, S.

2018-05-01

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

Review of Techniques to Achieve Optical Surface Cleanliness and Their Potential Application to Surgical Endoscopes

PubMed Central

Kreeft, Davey; Arkenbout, Ewout Aart; Henselmans, Paulus Wilhelmus Johannes; van Furth, Wouter R.; Breedveld, Paul

2017-01-01

A clear visualization of the operative field is of critical importance in endoscopic surgery. During surgery the endoscope lens can get fouled by body fluids (eg, blood), ground substance, rinsing fluid, bone dust, or smoke plumes, resulting in visual impairment. As a result, surgeons spend part of the procedure on intermittent cleaning of the endoscope lens. Current cleaning methods that rely on manual wiping or a lens irrigation system are still far from ideal, leading to longer procedure times, dirtying of the surgical site, and reduced visual acuity, potentially reducing patient safety. With the goal of finding a solution to these issues, a literature review was conducted to identify and categorize existing techniques capable of achieving optically clean surfaces, and to show which techniques can potentially be implemented in surgical practice. The review found that the most promising method for achieving surface cleanliness consists of a hybrid solution, namely, that of a hydrophilic or hydrophobic coating on the endoscope lens and the use of the existing lens irrigation system. PMID:28511635

Numerically accurate computational techniques for optimal estimator analyses of multi-parameter models

NASA Astrophysics Data System (ADS)

Berger, Lukas; Kleinheinz, Konstantin; Attili, Antonio; Bisetti, Fabrizio; Pitsch, Heinz; Mueller, Michael E.

2018-05-01

Modelling unclosed terms in partial differential equations typically involves two steps: First, a set of known quantities needs to be specified as input parameters for a model, and second, a specific functional form needs to be defined to model the unclosed terms by the input parameters. Both steps involve a certain modelling error, with the former known as the irreducible error and the latter referred to as the functional error. Typically, only the total modelling error, which is the sum of functional and irreducible error, is assessed, but the concept of the optimal estimator enables the separate analysis of the total and the irreducible errors, yielding a systematic modelling error decomposition. In this work, attention is paid to the techniques themselves required for the practical computation of irreducible errors. Typically, histograms are used for optimal estimator analyses, but this technique is found to add a non-negligible spurious contribution to the irreducible error if models with multiple input parameters are assessed. Thus, the error decomposition of an optimal estimator analysis becomes inaccurate, and misleading conclusions concerning modelling errors may be drawn. In this work, numerically accurate techniques for optimal estimator analyses are identified and a suitable evaluation of irreducible errors is presented. Four different computational techniques are considered: a histogram technique, artificial neural networks, multivariate adaptive regression splines, and an additive model based on a kernel method. For multiple input parameter models, only artificial neural networks and multivariate adaptive regression splines are found to yield satisfactorily accurate results. Beyond a certain number of input parameters, the assessment of models in an optimal estimator analysis even becomes practically infeasible if histograms are used. The optimal estimator analysis in this paper is applied to modelling the filtered soot intermittency in large eddy

Emerging Techniques for Dose Optimization in Abdominal CT

PubMed Central

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

2014-01-01

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

VEIL Surgical Steps.

PubMed

Raghunath, S K; Nagaraja, H; Srivatsa, N

2017-03-01

Inguinal lymphadenectomy remains the standard of care for metastatic nodal disease in cases of penile, urethral, vulval and vaginal cancers. Outcomes, including cure rates and overall and progression-free survivals, have progressively improved in these diseases with extending criteria to offer inguinal lymph node dissection for patients 'at-risk' for metastasis or loco-regional recurrence. Hence, despite declining incidence of advanced stages of these cancers, many patients will still need to undergo lymphadenectomy for optimal oncological outcomes. Inguinal node dissection is a morbid procedure with operative morbidity noted in almost two third of the patients. Video endoscopic inguinal lymphadenectomy (VEIL) was described and currently practiced with proven equivalent oncological outcomes. We describe our technique of VEIL using laparoscopic and robotic access as well as various new surgical strategies.

Survey on Robot-Assisted Surgical Techniques Utilization in US Pediatric Surgery Fellowships.

PubMed

Maizlin, Ilan I; Shroyer, Michelle C; Yu, David C; Martin, Colin A; Chen, Mike K; Russell, Robert T

2017-02-01

Robotic technology has transformed both practice and education in many adult surgical specialties; no standardized training guidelines in pediatric surgery currently exist. The purpose of our study was to assess the prevalence of robotic procedures and extent of robotic surgery education in US pediatric surgery fellowships. A deidentified survey measured utilization of the robot, perception on the utility of the robot, and its incorporation in training among the program directors of Accreditation Council for Graduate Medical Education (ACGME) pediatric surgery fellowships in the United States. Forty-one of the 47 fellowship programs (87%) responded to the survey. While 67% of respondents indicated the presence of a robot in their facility, only 26% reported its utilizing in their surgical practice. Among programs not utilizing the robot, most common reasons provided were lack of clear supportive evidence, increased intraoperative time, and incompatibility of instrument size to pediatric patients. While 58% of program directors believe that there is a future role for robotic surgery in children, only 18% indicated that robotic training should play a part in pediatric surgery education. Consequently, while over 66% of survey respondents received training in robot-assisted surgical technique, only 29% of fellows receive robot-assisted training during their fellowship. A majority of fellowships have access to a robot, but few utilize the technology in their current practice or as part of training. Further investigation is required into both the technology's potential benefits in the pediatric population and its role in pediatric surgery training.

The zygomatic implant perforated (ZIP) flap: a new technique for combined surgical reconstruction and rapid fixed dental rehabilitation following low-level maxillectomy.

PubMed

Butterworth, C J; Rogers, S N

2017-12-01

This aim of this report is to describe the development and evolution of a new surgical technique for the immediate surgical reconstruction and rapid post-operative prosthodontic rehabilitation with a fixed dental prosthesis following low-level maxillectomy for malignant disease.The technique involves the use of a zygomatic oncology implant perforated micro-vascular soft tissue flap (ZIP flap) for the primary management of maxillary malignancy with surgical closure of the resultant maxillary defect and the installation of osseointegrated support for a zygomatic implant-supported maxillary fixed dental prosthesis.The use of this technique facilitates extremely rapid oral and dental rehabilitation within a few weeks of resective surgery, providing rapid return to function and restoring appearance following low-level maxillary resection, even in cases where radiotherapy is required as an adjuvant treatment post-operatively. The ZIP flap technique has been adopted as a standard procedure in the unit for the management of low-level maxillary malignancy, and this report provides a detailed step-by-step approach to treatment and discusses modifications developed over the treatment of an initial cohort of patients.

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. Copyright © 2016 Elsevier Inc. All rights reserved.

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

PubMed

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

2008-11-01

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

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

Vocal fold submucosal infusion technique in phonomicrosurgery.

PubMed

Kass, E S; Hillman, R E; Zeitels, S M

1996-05-01

Phonomicrosurgery is optimized by maximally preserving the vocal fold's layered microstructure (laminae propriae). The technique of submucosal infusion of saline and epinephrine into the superficial lamina propria (SLP) was examined to delineate how, when, and why it was helpful toward this surgical goal. A retrospective review revealed that the submucosal infusion technique was used to enhance the surgery in 75 of 152 vocal fold procedures that were performed over the last 2 years. The vocal fold epithelium was noted to be adherent to the vocal ligament in 29 of the 75 cases: 19 from previous surgical scarring, 4 from cancer, 3 from sulcus vocalis, 2 from chronic hemorrhage, and 1 from radiotherapy. The submucosal infusion technique was most helpful when the vocal fold epithelium required resection and/or when extensive dissection in the SLP was necessary. The infusion enhanced the surgery by vasoconstriction of the microvasculature in the SLP, which improved visualization during cold-instrument tangential dissection. Improved visualization facilitated maximal preservation of the SLP, which is necessary for optimal pliability of the overlying epithelium. The infusion also improved the placement of incisions at the perimeter of benign, premalignant, and malignant lesions, and thereby helped preserve epithelium uninvolved by the disorder.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

1984-04-01

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

Surgical Management of Hemorrhoids

PubMed Central

Agbo, S. P.

2011-01-01

Hemorrhoids are common human afflictions known since the dawn of history. Surgical management of this condition has made tremendous progress from complex ligation and excision procedures in the past to simpler techniques that allow the patient to return to normal life within a short period. Newer techniques try to improve on the post-operative complications of older ones. The surgical options for the management of hemorrhoids today are many. Capturing all in a single article may be difficult if not impossible. The aim of this study therefore is to present in a concise form some of the common surgical options in current literature, highlighting some important post operative complications. Current literature is searched using MEDLINE, EMBASE and the Cochrane library. The conclusion is that even though there are many surgical options in the management of hemorrhoids today, most employ the ligature and excision technique with newer ones having reduced post operative pain and bleeding. PMID:22413048

Strategy in the Surgical Treatment of Primary Spinal Tumors

PubMed Central

Williams, Richard; Foote, Matthew; Deverall, Hamish

2012-01-01

Primary spine tumors are rare, accounting for only 4% of all tumors of the spine. A minority of the more common primary benign lesions will require surgical treatment, and most amenable malignant lesions will proceed to attempted resection. The rarity of malignant primary lesions has resulted in a paucity of historical data regarding optimal surgical and adjuvant treatment and, although we now derive benefit from standardized guidelines of overall care, management of each neoplasm often proceeds on a case-by-case basis, taking into account the individual characteristics of patient operability, tumor resectability, and biological potential. This article aims to provide an overview of diagnostic techniques, staging algorithms and the authors' experience of surgical treatment alternatives that have been employed in the care of selected benign and malignant lesions. Although broadly a review of contemporary management, it is hoped that the case illustrations given will serve as additional “arrows in the quiver” of the treating surgeon. PMID:24353976

Lordosis Re-Creation in TLIF and PLIF: A Cadaveric Study of the Influence of Surgical Bone Resection and Cage Angle.

PubMed

Robertson, Peter A; Armstrong, William A; Woods, Daniel L; Rawlinson, Jeremy J

2018-04-24

Controlled cadaveric study of surgical technique in Transforaminal and Posterior Lumbar Interbody Fusion (TLIF & PLIF) OBJECTIVE.: To evaluate the contribution of surgical techniques and cage variables in lordosis re-creation in posterior interbody fusion (TLIF/PLIF). The major contributors to lumbar lordosis are the lordotic lower lumbar discs. The pathologies requiring treatment with segmental fusion are frequently hypolordotic or kyphotic. Current posterior based interbody techniques have a poor track record for recreating lordosis, although re-creation of lordosis with optimum anatomical alignment is associated with better outcomes and reduced adjacent segment change needing revision. It is unclear whether surgical techniques or cage parameters contribute significantly to lordosis re-creation. Eight instrumented cadaveric motion segments were evaluated with pre and post experimental radiological assessment of lordosis. Each motion segment was instrumented with pedicle screw fixation to allow segmental stabilization. The surgical procedures were unilateral TLIF with an 18° lordotic and 27 mm length cage, unilateral TLIF (18°, 27 mm) with bilateral facetectomy, unilateral TLIF (18°, 27 mm) with posterior column osteotomy, PLIF with bilateral cages (18°, 22 mm), and PLIF with bilateral cages (24°, 22 mm). Cage insertion used and 'insert and rotate' technique. Pooled results demonstrated a mean increase in lordosis of 2.2° with each procedural step (Lordosis increase was serially 1.8°, 3.5°, 1.6°, 2.5° & 1.6° through the procedures). TLIF and PLIF with posterior column osteotomy increased lordosis significantly compared with Unilateral TLIF and TLIF with bilateral facetectomy. The major contributors to lordosis re-creation were posterior column osteotomy, and PLIF with paired shorter cages rather than TLIF. This study demonstrates that the surgical approach to posterior interbody surgery influences lordosis gain and posterior column osteotomy

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

PubMed

Khaimook, Araya; Borkird, Jumpot; Alapach, Sakda

2010-09-01

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

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

Surgical treatment of cholesteatoma: a comparison of three techniques.

PubMed

Toner, J G; Smyth, G D

1990-07-01

The debate regarding the surgical technique for the management of cholesteatoma still continues. The resolution of this issue will only come with the study of the long term results of well controlled series. In this paper long term follow-up on three groups of patients is reported. The groups underwent combined approach tympanoplasty (CAT), mastoid tympanoplasty with obliteration (MOT), and modified radical mastoidectomy (MRM) respectively for cholesteatoma. The factors studied included frequency of required review, condition of the external canal/cavity, and hearing status. The meatal cross-sectional areas and cavity volumes were also measured for the MRM and MOT groups. Analysis of the data showed no significant difference between the groups in either frequency of review or cavity status. The hearing results showed an initial improvement in all groups, however, over the prolonged follow-up period the air conduction threshold gradually increased. In conclusion this data supports the view that a one-stage canal wall down procedure provides maximum long term patient benefit.

Comparison of a new hydro-surgical technique to traditional methods for the preparation of full-thickness skin grafts from canine cadaveric skin and report of a single clinical case.

PubMed

Townsend, F I; Ralphs, S C; Coronado, G; Sweet, D C; Ward, J; Bloch, C P

2012-01-01

To compare the hydro-surgical technique to traditional techniques for removal of subcutaneous tissue in the preparation of full-thickness skin grafts. Ex vivo experimental study and a single clinical case report. Four canine cadavers and a single clinical case. Four sections of skin were harvested from the lateral flank of recently euthanatized dogs. Traditional preparation methods used included both a blade or scissors technique, each of which were compared to the hydro-surgical technique individually. Preparation methods were compared based on length of time for removal of the subcutaneous tissue from the graft, histologic grading, and measurable thickness as compared to an untreated sample. The hydro-surgical technique had the shortest skin graft preparation time as compared to traditional techniques (p = 0.002). There was no significant difference in the histological grading or measurable subcutaneous thickness between skin specimens. The hydro-surgical technique provides a rapid, effective debridement of subcutaneous tissue in the preparation of full-thickness skin grafts. There were not any significant changes in histological grade and subcutaneous tissue remaining among all treatment types. Additionally the hydro-surgical technique was successfully used to prepare a full-thickness meshed free skin graft in the reconstruction of a traumatic medial tarsal wound in a dog.

Parastomal hernia mesh repair, variant of surgical technique without stoma relocation.

PubMed

Guriţă, P; Popa, R; Bălălău, B; Scăunaşu, R

2012-06-12

Due to the improvement of prognosis through adjuvant therapy, the life expectancy of neoplasia patients is continuously increasing, which, in conjunction with the progressive occurrence of parastomal hernias during the disease evolution, explains the growing number of reported parastomal hernias affecting patients with permanent colostomy. Conventional techniques of local repair are inappropriate considering the high recurrence rate, and the decision of stoma relocation depends on the associated pathology, which may counter-indicate general anesthesia, and on previous surgical interventions that are usually followed by a dense peritoneal adhesion syndrome. The purpose of this article is to make known a variant of alloplastic technique, without translocation, with a low degree of invasiveness, which can be performed successfully under spinal anesthesia, followed by a reduced period of hospitalization. The study group consisted of 6 patients with permanent left iliac anus who underwent these interventions one to three years prior to the occurrence of parastomal hernia. Patients were followed at 1 year and 2 years postoperatively and the results were favorable, with no recurrence and improved quality of life through proper prosthesis of the stoma. We suggest that this technique variation is applied to small and medium parastomal hernias, in case of patients with permanent left iliac anus, with the declared intent of minimal invasiveness.

Tuning of PID controller using optimization techniques for a MIMO process

NASA Astrophysics Data System (ADS)

Thulasi dharan, S.; Kavyarasan, K.; Bagyaveereswaran, V.

2017-11-01

In this paper, two processes were considered one is Quadruple tank process and the other is CSTR (Continuous Stirred Tank Reactor) process. These are majorly used in many industrial applications for various domains, especially, CSTR in chemical plants.At first mathematical model of both the process is to be done followed by linearization of the system due to MIMO process and controllers are the major part to control the whole process to our desired point as per the applications so the tuning of the controller plays a major role among the whole process. For tuning of parameters we use two optimizations techniques like Particle Swarm Optimization, Genetic Algorithm. The above techniques are majorly used in different applications to obtain which gives the best among all, we use these techniques to obtain the best tuned values among many. Finally, we will compare the performance of the each process with both the techniques.

Frontal Lobe Decortication (Frontal Lobectomy with Ventricular Preservation) in Epilepsy-Part 1: Anatomic Landmarks and Surgical Technique.

PubMed

Wen, Hung Tzu; Da Róz, Leila Maria; Rhoton, Albert L; Castro, Luiz Henrique Martins; Teixeira, Manoel Jacobsen

2017-02-01

An extensive frontal resection is a frequently performed neurosurgical procedure, especially for treating brain tumor and refractory epilepsy. However, there is a paucity of reports available regarding its surgical anatomy and technique. We sought to present the anatomic landmarks and surgical technique of the frontal lobe decortication (FLD) in epilepsy. The goals were to maximize the gray matter removal, spare primary and supplementary motor areas, and preserve the frontal horn. The anatomic study was based on dissections performed in 15 formalin-fixed adult cadaveric heads. The clinical experience with 15 patients is summarized. FLD consists of 5 steps: 1) coagulation and section of arterial branches of lateral surface; 2) paramedian subpial resection 3 cm ahead of the precentral sulcus to reach the genu of corpus callosum; 3) resection of gray matter of lateral surface, preserving the frontal horn; 4) removal of gray matter of basal surface preserving olfactory tract; 5) removal of gray matter of the medial surface under the rostrum of corpus callosum. The frontal horn was preserved in all 15 patients; 12 patients (80%) had no complications; 2 patients presented temporary hemiparesis; and 1 Rasmussen syndrome patient developed postoperative fever. The best seizure control was in cases with focal magnetic resonance imaging abnormalities limited to the frontal lobe. FLD is an anatomy-based surgical technique for extensive frontal lobe resection. It presents reliable anatomic landmarks, selective gray matter removal, preservation of frontal horn, and low complication rate in our series. It can be an alternative option to the classical frontal lobectomy. Copyright © 2016 Elsevier Inc. All rights reserved.

GPU-based efficient realistic techniques for bleeding and smoke generation in surgical simulators.

PubMed

Halic, Tansel; Sankaranarayanan, Ganesh; De, Suvranu

2010-12-01

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

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

PubMed Central

Halic, Tansel; Sankaranarayanan, Ganesh; De, Suvranu

2010-01-01

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

Proximal hypospadias: A persistent challenge. Single institution outcome analysis of three surgical techniques over a 10-year period.

PubMed

Pippi Salle, J L; Sayed, S; Salle, A; Bagli, D; Farhat, W; Koyle, M; Lorenzo, A J

2016-02-01

The optimal treatment of proximal hypospadias remains controversial. Several techniques have been described, but the best approach remains unsettled. To evaluate and compare the complication rates of proximal hypospadias with and without ventral curvature (VC), according to three different surgical techniques: tubularized incised plate (TIP) uretroplasty, dorsal inlay graft TIP (DIG), and staged preputial repair (SR). It was hypothesized that SR performs better than TIP and DIG for proximal hypospadias. Single-center, retrospective chart review of all patients with primary proximal hypospadias reconstructed between 2003 and 2013. The DIG was selectively employed in cases with narrow urethral plate (UP) and deficient spongiosum. Extensive urethral plate (UP) mobilization (UPM), dorsal plication (DP) and/or deep transverse incisions of tunica albuginea (DTITA) were selectively performed when attempting to spare transecting the UP. Division of UP and SR was favored in cases with severe VC (>50°), which was often concurrently managed with DTITA if intrinsic curvature was present. For SR, tubularization of the graft was performed 6 months later. A total of 140 patients were included. Tubularized incised plate (TIP), DIG, and SR techniques were performed in 57, 23, and 60 patients, respectively. The TIP and DIG techniques achieved similar success rates, although DIG was performed in cases of narrow and spongiosum-deficient plates. Reoperation rates with TIP and DIG techniques was 52.6% and 52.1% (NS). Urethro-cutaneous fistulas were seen in 31.5% and 13% of TIP and DIG techniques, respectively. Staged repair accomplished better results than both TIP and DIG techniques, despite being performed in the most unfavorable cases (reoperation rate 28%). After technical modifications, the DIG technique achieved similar outcomes of SR. Proximal hypospadias remains challenging, regardless of the technique utilized for its repair. Urethro-cutaneous fistulas were more commonly seen

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

PubMed

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

2001-10-01

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

Trans-venous embolization of a basal ganglia ruptured arteriovenous malformation with open surgical arterial control: A hybrid technique.

PubMed

Kulcsár, Zsolt; Machi, Paolo; Schaller, Karl; Lovblad, Karl Olof; Bijlenga, Philippe

2018-05-01

Treatment of ruptured deep-seated arteriovenous malformations is challenging and associated with elevated risks. This is due to the proximity or involvement of critical brain structures and the specifically fine and delicate angioarchitecture of these lesions, making both endovascular and surgical access technically complicated. We present the advantages of a true combined, open surgical and endovascular transvenous approach in a hybrid operating room. The technique may overcome in part the difficulties and may improve safety and risk related concerns. Copyright © 2018. Published by Elsevier Masson SAS.

Contemporary surgical treatment of benign prostatic hyperplasia.

PubMed

Nunes, Ricardo Luís Vita; Antunes, Alberto Azoubel; Constantin, Davi Souza

2017-08-01

Benign prostatic hyperplasia (BPH) is a common condition in adult men and its incidence increases progressively with aging. It has an important impact on the individual's physical and mental health and its natural progression can lead to serious pathological situations. Although the initial treatment is pharmacological, except in specific situations, the tendency of disease progression causes a considerable portion of the patients to require surgical treatment. In this case, there are several options available today in the therapeutic armamentarium. Among the options, established techniques, such as open surgery and endoscopic resection using monopolar energy, still prevail in the choice of surgeons because they are more accessible, both from a socioeconomic standpoint in the vast majority of medical services and in terms of training of medical teams. On the other hand, new techniques and technologies arise sequentially in order to minimize aggression, surgical time, recovery and complications, optimizing results related to the efficacy/safety dyad. Each of these techniques has its own peculiarities regarding availability due to cost, learning curve and scientific consolidation in order to achieve recognition as a cutting-edge method in the medical field. The use of bipolar energy in endoscopic resection of the prostate, laser vaporization and enucleation techniques, and videolaparoscopy are examples of new options that have successfully traced this path. Robot-assisted surgery has gained a lot of space in the last decade, but it still needs to dodge the trade barrier. Other techniques and technologies will need to pass the test of time to be able to conquer their space in this growing market.

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

PubMed

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

2008-01-01

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

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.

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

PubMed

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

2014-09-01

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

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

PubMed

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

2009-02-01

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

Surgical robotics for patient safety in the perioperative environment: realizing the promise.

PubMed

Fuji Lai; Louw, Deon

2007-06-01

Surgery is at a crossroads of complexity. However, there is a potential path toward patient safety. One such course is to leverage computer and robotic assist techniques in the reduction and interception of error in the perioperative environment. This white paper attempts to facilitate the road toward realizing that promise by outlining a research agenda. The paper will briefly review the current status of surgical robotics and summarize any conclusions that can be reached to date based on existing research. It will then lay out a roadmap for future research to determine how surgical robots should be optimally designed and integrated into the perioperative workflow and process. Successful movement down this path would involve focused efforts and multiagency collaboration to address the research priorities outlined, thereby realizing the full potential of surgical robotics to augment human capabilities, enhance task performance, extend the reach of surgical care, improve health care quality, and ultimately enhance patient safety.

Preoperative surgical rehearsal using cadaveric fresh tissue surgical simulation increases resident operative confidence.

PubMed

Weber, Erin L; Leland, Hyuma A; Azadgoli, Beina; Minneti, Michael; Carey, Joseph N

2017-08-01

Rehearsal is an essential part of mastering any technical skill. The efficacy of surgical rehearsal is currently limited by low fidelity simulation models. Fresh cadaver models, however, offer maximal surgical simulation. We hypothesize that preoperative surgical rehearsal using fresh tissue surgical simulation will improve resident confidence and serve as an important adjunct to current training methods. Preoperative rehearsal of surgical procedures was performed by plastic surgery residents using fresh cadavers in a simulated operative environment. Rehearsal was designed to mimic the clinical operation, complete with a surgical technician to assist. A retrospective, web-based survey was used to assess resident perception of pre- and post-procedure confidence, preparation, technique, speed, safety, and anatomical knowledge on a 5-point scale (1= not confident, 5= very confident). Twenty-six rehearsals were performed by 9 residents (PGY 1-7) an average of 4.7±2.1 days prior to performance of the scheduled operation. Surveys demonstrated a median pre-simulation confidence score of 2 and a post-rehearsal score of 4 (P<0.01). The perceived improvement in confidence and performance was greatest when simulation was performed within 3 days of the scheduled case. All residents felt that cadaveric simulation was better than standard preparation methods of self-directed reading or discussion with other surgeons. All residents believed that their technique, speed, safety, and anatomical knowledge improved as a result of simulation. Fresh tissue-based preoperative surgical rehearsal was effectively implemented in the residency program. Resident confidence and perception of technique improved. Survey results suggest that cadaveric simulation is beneficial for all levels of residents. We believe that implementation of preoperative surgical rehearsal is an effective adjunct to surgical training at all skill levels in the current environment of decreased work hours.

Endoscopic vs. Surgical Interventions for Painful Chronic Pancreatitis: What is Needed for Future Clinical Trials

PubMed Central

Windsor, John A; Reddy, Nageshwar D

2017-01-01

The treatment of painful chronic pancreatitis remains controversial. The available evidence from two randomized controlled trials favor surgical intervention, whereas an endotherapy-first approach is widely practiced. Chronic pancreatitis is complex disease with different genetic and environmental factors, different pain mechanisms and different treatment modalities including medical, endoscopic, and surgical. The widely practiced step-up approach remains unproven. In designing future clinical trials there are some important pre-requisites including a more comprehensive pain assessment tool, the optimization of conservative medical treatment and interventional techniques. Consideration should be given to the need of a control arm and the optimal timing of intervention. Pending better designed studies, the practical way forward is to identify subgroups of patients who clearly warrant endotherapy or surgery first, and to design the future clinical trials for the remainder. PMID:28079861

Mental training in surgical education: a systematic review.

PubMed

Davison, Sara; Raison, Nicholas; Khan, Muhammad S; Dasgupta, Prokar; Ahmed, Kamran

2017-11-01

Pressures on surgical education from restricted working hours and increasing scrutiny of outcomes have been compounded by the development of highly technical surgical procedures requiring additional specialist training. Mental training (MT), the act of performing motor tasks in the 'mind's eye', offers the potential for training outside the operating room. However, the technique is yet to be formally incorporated in surgical curricula. This study aims to review the available literature to determine the role of MT in surgical education. EMBASE and Medline databases were searched. The primary outcome measure was surgical proficiency following training. Secondary analyses examined training duration, forms of MT and trainees level of experience. Study quality was assessed using Consolidated Standards of Reporting Trials scores or Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group. Fourteen trials with 618 participants met the inclusion criteria, of which 11 were randomized and three longitudinal. Ten studies found MT to be beneficial. Mental rehearsal was the most commonly used form of training. No significant correlation was found between the length of MT and outcomes. MT benefitted expert surgeons more than medical students or novice surgeons. The majority studies demonstrate MT to be beneficial in surgical education especially amongst more experienced surgeons within a well-structured MT programme. However, overall studies were low quality, lacked sufficient methodology and suffered from small sample sizes. For these reasons, further research is required to determine optimal role of MT as a supplementary educational tool within the surgical curriculum. © 2017 Royal Australasian College of Surgeons.

FREQUENCY OF LINGUAL NERVE INJURY IN MANDIBULAR THIRD MOLAR EXTRACTION: A COMPARISON OF TWO SURGICAL TECHNIQUES.

PubMed

Shad, Samia; Shah, Syed Majid Hussain; Alamgir; Abbasi, Masroor Manshad

2015-01-01

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

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

PubMed

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

2018-02-23

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

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

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

PubMed

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

2016-11-01

Ulnar collateral ligament reconstruction (UCLR) has become a common procedure performed in overhead-throwing athletes of many athletic levels. 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. Cohort study; Level of evidence, 3. 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. 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). Both the docking and double-docking techniques produce excellent clinical outcomes in patients undergoing UCLR. No difference in outcome scores was seen between surgical technique

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

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

PubMed Central

Bhardwaj, Ashu; Sultan, Nishat; Sawai, Madhuri; Jafri, Zeba

2016-01-01

Moderate-to-severe chronic periodontitis results in clinical loss of attachment, reduced width of attached gingiva (AG), periodontal pockets beyond mucogingival junction (MGJ), gingival recession, loss of alveolar bone, and decreased vestibular depth (VD). The encroachment of frenal and muscle attachments on marginal gingiva increases the rate of progression of periodontal pockets, prevents healing, and causes their recurrence after therapy. Loss of VD and AG associated with continuous progression of pocket formation and bone loss requires two-stage surgical procedures. In this article, one-stage surgical procedure is being described for the first time, to treat the periodontal pockets extending beyond the MGJ by periodontal flap surgery along with vestibular deepening with diode laser to increase the AG. One-step surgical technique is illustrated whereby pocket therapy with reconstruction of lost periodontal tissues can be done along with gingival augmentation by vestibular deepening. PMID:29238149

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

Parastomal hernia mesh repair, variant of surgical technique without stoma relocation

PubMed Central

Guriţă, P; Popa, R; Bălălău, B; Scăunaşu, R

2012-01-01

Rationale:Due to the improvement of prognosis through adjuvant therapy, the life expectancy of neoplasia patients is continuously increasing, which, in conjunction with the progressive occurrence of parastomal hernias during the disease evolution, explains the growing number of reported parastomal hernias affecting patients with permanent colostomy. Conventional techniques of local repair are inappropriate considering the high recurrence rate, and the decision of stoma relocation depends on the associated pathology, which may counter-indicate general anesthesia, and on previous surgical interventions that are usually followed by a dense peritoneal adhesion syndrome . Objective:The purpose of this article is to make known a variant of alloplastic technique, without translocation, with a low degree of invasiveness, which can be performed successfully under spinal anesthesia, followed by a reduced period of hospitalization. Methods and Results:The study group consisted of 6 patients with permanent left iliac anus who underwent these interventions one to three years prior to the occurrence of parastomal hernia. Patients were followed at 1 year and 2 years postoperatively and the results were favorable, with no recurrence and improved quality of life through proper prosthesis of the stoma Discussion:We suggest that this technique variation is applied to small and medium parastomal hernias, in case of patients with permanent left iliac anus, with the declared intent of minimal invasiveness. PMID:22802882

No differences in subjective knee function between surgical techniques of anterior cruciate ligament reconstruction at 2-year follow-up: a cohort study from the Swedish National Knee Ligament Register.

PubMed

Hamrin Senorski, Eric; Sundemo, David; Murawski, Christopher D; Alentorn-Geli, Eduard; Musahl, Volker; Fu, Freddie; Desai, Neel; Stålman, Anders; Samuelsson, Kristian

2017-12-01

The purpose of this study was to investigate how different techniques of single-bundle anterior cruciate ligament (ACL) reconstruction affect subjective knee function via the Knee injury and Osteoarthritis Outcome Score (KOOS) evaluation 2 years after surgery. It was hypothesized that the surgical techniques of single-bundle ACL reconstruction would result in equivalent results with respect to subjective knee function 2 years after surgery. This cohort study was based on data from the Swedish National Knee Ligament Register during the 10-year period of 1 January 2005 through 31 December 2014. Patients who underwent primary single-bundle ACL reconstruction with hamstrings tendon autograft were included. Details on surgical technique were collected using a web-based questionnaire comprised of essential AARSC items, including utilization of accessory medial portal drilling, anatomic tunnel placement, and visualization of insertion sites and landmarks. A repeated measures ANOVA and an additional linear mixed model analysis were used to investigate the effect of surgical technique on the KOOS 4 from the pre-operative period to 2-year follow-up. A total of 13,636 patients who had undergone single-bundle ACL reconstruction comprised the study group for this analysis. A repeated measures ANOVA determined that mean subjective knee function differed between the pre-operative time period and at 2-year follow-up (p < 0.001). No differences were found with respect to the interaction between KOOS 4 and surgical technique or gender. Additionally, the linear mixed model adjusted for age at reconstruction, gender, and concomitant injuries showed no difference between surgical techniques in KOOS 4 improvement from baseline to 2-year follow-up. However, KOOS 4 improved significantly in patients for all surgical techniques of single-bundle ACL reconstruction (p < 0.001); the largest improvement was seen between the pre-operative time period and at 1-year follow-up. Surgical

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.

Central polydactyly of the foot: surgical management with plantar and dorsal advancement flaps.

PubMed

Osborn, Emily J; Davids, Jon R; Leffler, Lauren C; Gibson, Thomas W; Pugh, Linda I

2014-01-01

Central polydactyly is the least common form of foot polydactyly, and the intercalary location of the duplicated ray makes the surgical exposure, excision, and closure more complex. For these reasons there is little consensus concerning the optimal technique for surgical management. A retrospective case series of 22 patients with 27 feet with central polydactyly, treated surgically by the dorsal and plantar advancement flap technique, was performed. Change in width of the forefoot was measured from radiographs by the metatarsal gap ratio. Functional outcomes were assessed by the Foot and Ankle Ability Measure. Signficant narrowing of the forefoot, as measured radiographically by the metatarsal gap ratio, was achieved after surgery (P<0.0001). This radiographic narrowing was maintained with growth after a mean follow-up of 8 years (P=0.0001). In 7 of the unilateral cases, the mean forefoot radiographic width of the affected side, after surgical resection and reconstruction of the central polydactyly, was 2% greater than the contralateral, uninvolved side. Persistent clinical widening of the forefoot after surgery was reported in the majority (82%) of cases. The Foot and Ankle Ability Measure results showed near-normal functional outcomes in itemized activities of daily living, itemized sports, and overall function categories. The few reports of less than normal foot function were related to shoe wear issues and incisional scarring that was painful or cosmetically unappealing. The radiographic and functional outcomes after surgical management of central polydactyly with the dorsal and plantar advancement flap technique are excellent. The technique successfully narrows the forefoot on radiographs, and this narrowing is maintained with growth over time. However, families should be advised that persistent perceived widening of the forefoot relative to normal is common, despite successful radiographic narrowing after surgery. IV.

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

PubMed

Cassetta, M; Giansanti, M

2016-07-01

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. 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. 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. The effectiveness of this minimally-invasive surgical technique can offer the clinician a valid alternative to other methods currently in use.

Optimal lay-up design of variable stiffness laminated composite plates by a layer-wise optimization technique

NASA Astrophysics Data System (ADS)

Houmat, A.

2018-02-01

The optimal lay-up design for the maximum fundamental frequency of variable stiffness laminated composite plates is investigated using a layer-wise optimization technique. The design variables are two fibre orientation angles per ply. Thin plate theory is used in conjunction with a p-element to calculate the fundamental frequencies of symmetrically and antisymmetrically laminated composite plates. Comparisons with existing optimal solutions for constant stiffness symmetrically laminated composite plates show excellent agreement. It is observed that the maximum fundamental frequency can be increased considerably using variable stiffness design as compared to constant stiffness design. In addition, optimal lay-ups for the maximum fundamental frequency of variable stiffness symmetrically and antisymmetrically laminated composite plates with different aspect ratios and various combinations of free, simply supported and clamped edge conditions are presented. These should prove a useful benchmark for optimal lay-ups of variable stiffness laminated composite plates.

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. Copyright © 2016. Published by Elsevier Ltd.

Connection between optimal control theory and adiabatic-passage techniques in quantum systems

NASA Astrophysics Data System (ADS)

Assémat, E.; Sugny, D.

2012-08-01

This work explores the relationship between optimal control theory and adiabatic passage techniques in quantum systems. The study is based on a geometric analysis of the Hamiltonian dynamics constructed from Pontryagin's maximum principle. In a three-level quantum system, we show that the stimulated Raman adiabatic passage technique can be associated to a peculiar Hamiltonian singularity. One deduces that the adiabatic pulse is solution of the optimal control problem only for a specific cost functional. This analysis is extended to the case of a four-level quantum system.

In-hospital cost comparison between the standard lateral and supercapsular percutaneously-assisted total hip surgical techniques for total hip replacement.

PubMed

Gofton, Wade; Fitch, David A

2016-03-01

The purpose of this study was to compare the in-hospital costs associated with the tissue-sparing supercapsular percutaneously-assisted total hip (SuperPath) and traditional Lateral surgical techniques for total hip replacement (THR). Between April 2013 and January 2014, in-hospital costs were reviewed for all THRs performed using the SuperPath technique by a single surgeon and all THRs performed using the Lateral technique by another surgeon at the same institution. Overall, costs were 28.4% higher in the Lateral group. This was largely attributable to increased costs associated with transfusion (+92.5%), patient rooms (+60.4%), patient food (+62.8%), narcotics (+42.5%), physical therapy (+52.5%), occupational therapy (+88.6%), and social work (+92.9%). The only costs noticeably increased for SuperPath were for imaging (+105.9%), and this was because the SuperPath surgeon performed intraoperative radiographs on all patients while the Lateral surgeon did not. The use of the SuperPath technique resulted in in-hospital cost reductions of over 28%, suggesting that this tissue-sparing surgical technique can be cost-effective primarily by facilitating early mobilisation and patient discharge even during a surgeon's initial experience with the approach.

Achilles Tendon Rupture: Avoiding Tendon Lengthening during Surgical Repair and Rehabilitation

PubMed Central

Maquirriain, Javier

2011-01-01

Achilles tendon rupture is a serious injury for which the best treatment is still controversial. Its primary goal should be to restore normal length and tension, thus obtaining an optimal function. Tendon elongation correlates significantly with clinical outcome; lengthening is an important cause of morbidity and may produce permanent functional impairment. In this article, we review all factors that may influence the repair, including the type of surgical technique, suture material, and rehabilitation program, among many others. PMID:21966048

Anatomy and Surgical Approaches to the Rabbit Nasal Septum.

PubMed

Badran, Karam W; Chang, John C; Kuan, Edward C; Wong, Brian J F

2017-09-01

The rabbit is the primary animal model used to investigate aspects of nasal surgery. Although several studies have used this model, none has provided a comprehensive analysis of the surgical anatomy and techniques used to gain access to the rabbit nasal fossae and septum. To describe and optimize the surgical anatomy and approach to the rabbit nasal vault and septal cartilage. In an ex vivo animal study conducted at an academic medical center, preliminary cadaveric dissections were performed on rabbit head specimens to establish familiarity with relevant anatomy and rehearse various approaches. Live Pasteurella-free New Zealand white rabbits (3.5-4.0 kg) were used to further develop this surgical technique developed here. Access of the nasal vault was gained through a midline nasal dorsum incision and creation of an osteoplastic flap with a drill. Submucosal resection was performed with preservation of the mucoperichondrium. All rabbits were monitored daily for 4 weeks in the postoperative period for signs of infection, pain, and complications. The study was conducted from June 1, 2014, to December 1, 2014. Surgical anatomy and techniques used to gain access to the rabbit nasal vault and harvest septal cartilage. Four Pasteurella-free New Zealand white rabbits (Western Organ Rabbit Co), ranging in age from 9 to 12 months and weighing between 3.5 and 4.0 kg, were used in this study. Initial dissections demonstrated the feasibility of harvesting septal cartilage while preserving the mucoperichondrial envelope. Access to the nasal vault through this 3-osteotomy approach allowed for maximal exposure to the nasal cavity bilaterally while maintaining the integrity of the mucoperichondrium following septal cartilage harvest. The maximum amount of bulk, en bloc, cartilage harvested was 1.0 × 2.5 cm. Following surgical dissection, all animals maintained adequate airway patency and support to midface structures. Furthermore, all specimens preserved the integrity of the

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

PubMed

Guneri, Cagri; Kirac, Mustafa; Biri, Hasan

2017-03-01

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

Optimization Techniques for Analysis of Biological and Social Networks

DTIC Science & Technology

2012-03-28

analyzing a new metaheuristic technique, variable objective search. 3. Experimentation and application: Implement the proposed algorithms , test and fine...alternative mathematical programming formulations, their theoretical analysis, the development of exact algorithms , and heuristics. Originally, clusters...systematic fashion under a unifying theoretical and algorithmic framework. Optimization, Complex Networks, Social Network Analysis, Computational

Use of three-dimensional finite element models of the lateral ankle ligaments to evaluate three surgical techniques

PubMed Central

Wang, Cheng-Wei; Muheremu, Aikeremujiang; Bai, Jing-Ping

2017-01-01

Objective To compare three surgical techniques for lateral ankle ligament reconstruction using finite element (FE) models. Methods A three-dimensional FE model of the left foot of a healthy volunteer and lateral collateral ligament injury models were developed. Three tendons [one-half of the autologous peroneus longus tendon (PLT), one-half of the peroneus brevis tendon (PBT), and an allogeneic tendon] were used for lateral collateral ligament reconstruction. The ankle varus stress and anterior drawer tests were performed to compare the three surgical techniques. Results The ankle varus stress test showed that the equivalent stresses of the anterior talofibular ligament (ATFL) (84.00 MPa) and calcaneofibular ligament (CFL) (27.01 MPa) were lower in allogeneic tendon reconstruction than in the other two techniques but similar to those of normal individuals (138.48 and 25.90 MPa, respectively). The anterior drawer test showed that the equivalent stresses of the ATFL and CFL in autologous PLT reconstruction (31.31 and 28.60 MPa, respectively) and PBT reconstruction (31.47 and 29.07 MPa, respectively) were lower than those in allogeneic tendon reconstruction (57.32 and 52.20 MPa, respectively). Conclusions The allogeneic tendon reconstruction outcome was similar to normal individuals. Allogeneic tendon reconstruction may be superior for lateral ankle ligament reconstruction without considering its complications. PMID:29239256

Explaining the absence of surgical procedure regulation.

PubMed

Darrow, Jonathan J

Each year in the United States, surgeons perform approximately 64 million surgical procedures, ranging from tooth extraction to open heart surgery. Yet, notwithstanding the frequency of surgical procedures and their often critical importance to patient health, no state or federal agency either approves the use of new surgical procedures or directly regulates existing procedures. The absence of surgical procedure regulation differs from the regulation of new pharmaceutical products, which can be introduced into interstate commerce only after the Food and Drug Administration (FDA) has reviewed "adequate and well-controlled [clinical] investigations" and concluded the data from those studies sufficiently establish the drug's safety and efficacy. Surgical procedures, by contrast, are more often conveyed from professor to student, the result being that surgical approaches may vary considerably from one geographic region to another. Whether different techniques produce different outcomes is not always clear, in part because the absence of regulation means that evidence often has not been systematically generated or may be in a form not suitable for comparison. Commentators have noted the differing treatment that persists between surgery and pharmaceuticals and have offered a number of justifications. For example, they have suggested that the surgical profession should self-regulate, that excessive regulation could deter surgeries of unproven benefit even when the surgery may be in the best interest of the patient, and that surgical trials could disrupt the doctor-patient relationship, such as by emphasizing uncertainty in a context where patient trust is important. In the context of innovative (as opposed to established) surgical procedures, controlled trials might be disfavored due to concern that desperate patients might unwisely submit themselves to risky experimental treatments undertaken by overzealous researchers. When commentators advocate for increased surgical

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

PubMed

Paci, Gabrielle M; Yao, Jeffrey

2015-01-01

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

A knowledge-based approach to improving optimization techniques in system planning

NASA Technical Reports Server (NTRS)

Momoh, J. A.; Zhang, Z. Z.

1990-01-01

A knowledge-based (KB) approach to improve mathematical programming techniques used in the system planning environment is presented. The KB system assists in selecting appropriate optimization algorithms, objective functions, constraints and parameters. The scheme is implemented by integrating symbolic computation of rules derived from operator and planner's experience and is used for generalized optimization packages. The KB optimization software package is capable of improving the overall planning process which includes correction of given violations. The method was demonstrated on a large scale power system discussed in the paper.

Solid oxide fuel cell simulation and design optimization with numerical adjoint techniques

NASA Astrophysics Data System (ADS)

Elliott, Louie C.

This dissertation reports on the application of numerical optimization techniques as applied to fuel cell simulation and design. Due to the "multi-physics" inherent in a fuel cell, which results in a highly coupled and non-linear behavior, an experimental program to analyze and improve the performance of fuel cells is extremely difficult. This program applies new optimization techniques with computational methods from the field of aerospace engineering to the fuel cell design problem. After an overview of fuel cell history, importance, and classification, a mathematical model of solid oxide fuel cells (SOFC) is presented. The governing equations are discretized and solved with computational fluid dynamics (CFD) techniques including unstructured meshes, non-linear solution methods, numerical derivatives with complex variables, and sensitivity analysis with adjoint methods. Following the validation of the fuel cell model in 2-D and 3-D, the results of the sensitivity analysis are presented. The sensitivity derivative for a cost function with respect to a design variable is found with three increasingly sophisticated techniques: finite difference, direct differentiation, and adjoint. A design cycle is performed using a simple optimization method to improve the value of the implemented cost function. The results from this program could improve fuel cell performance and lessen the world's dependence on fossil fuels.

A matrix equation solution by an optimization technique

NASA Technical Reports Server (NTRS)

Johnson, M. J.; Mittra, R.

1972-01-01

The computer solution of matrix equations is often difficult to accomplish due to an ill-conditioned matrix or high noise levels. Two methods of solution are compared for matrices of various degrees of ill-conditioning and for various noise levels in the right hand side vector. One method employs the usual Gaussian elimination. The other solves the equation by an optimization technique and employs a function minimization subroutine.

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

PubMed

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

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

Computed Tomographic Analysis of Ventral Atlantoaxial Optimal Safe Implantation Corridors in 27 Dogs.

PubMed

Leblond, Guillaume; Gaitero, Luis; Moens, Noel M M; Zur Linden, Alex; James, Fiona M K; Monteith, Gabrielle J; Runciman, John

2017-11-01

Objectives  Ventral atlantoaxial stabilization techniques are challenging surgical procedures in dogs. Available surgical guidelines are based upon subjective anatomical landmarks, and limited radiographic and computed tomographic data. The aims of this study were (1) to provide detailed anatomical descriptions of atlantoaxial optimal safe implantation corridors to generate objective recommendations for optimal implant placements and (2) to compare anatomical data obtained in non-affected Toy breed dogs, affected Toy breed dogs suffering from atlantoaxial instability and non-affected Beagle dogs. Methods  Anatomical data were collected from a prospectively recruited population of 27 dogs using a previously validated method of optimal safe implantation corridor analysis using computed tomographic images. Results  Optimal implant positions and three-dimensional numerical data were generated successfully in all cases. Anatomical landmarks could be used to generate objective definitions of optimal insertion points which were applicable across all three groups. Overall the geometrical distribution of all implant sites was similar in all three groups with a few exceptions. Clinical Significance  This study provides extensive anatomical data available to facilitate surgical planning of implant placement for atlantoaxial stabilization. Our data suggest that non-affected Toy breed dogs and non-affected Beagle dogs constitute reasonable research models to study atlantoaxial stabilization constructs. Schattauer GmbH Stuttgart.

Multispectral tissue characterization for intestinal anastomosis optimization.

PubMed

Cha, Jaepyeong; Shademan, Azad; Le, Hanh N D; Decker, Ryan; Kim, Peter C W; Kang, Jin U; Krieger, Axel

2015-10-01

Intestinal anastomosis is a surgical procedure that restores bowel continuity after surgical resection to treat intestinal malignancy, inflammation, or obstruction. Despite the routine nature of intestinal anastomosis procedures, the rate of complications is high. Standard visual inspection cannot distinguish the tissue subsurface and small changes in spectral characteristics of the tissue, so existing tissue anastomosis techniques that rely on human vision to guide suturing could lead to problems such as bleeding and leakage from suturing sites. We present a proof-of-concept study using a portable multispectral imaging (MSI) platform for tissue characterization and preoperative surgical planning in intestinal anastomosis. The platform is composed of a fiber ring light-guided MSI system coupled with polarizers and image analysis software. The system is tested on ex vivo porcine intestine tissue, and we demonstrate the feasibility of identifying optimal regions for suture placement.

Advantages and disadvantages of surgical placement of PD catheters with regard to other methods.

PubMed

Stegmayr, B

2006-01-01

Peritoneal dialysis is underused for various reasons. One reason may be problems with insertion of catheters for access. Another reason is the delayed start (break-in period) of about 2 weeks after operation. This review describes various approaches to the insertion of a peritoneal dialysis catheter. The optimal conditions to strive for are given as is an overview of various techniques. This article favours surgical placement while others might prefer other techniques. Described is the use a 3-purse string suture technique that allows immediate start of dialysis after catheter insertion both for acute dialysis indications as well as for acute start in chronic dialysis patients. A key to lesser complications is to establish a team devoted to the insertions rather than to allow various physicians to perform insertions as a training procedure. An optimal access is one of the important life lines for these patients.

Comparison of Artificial Immune System and Particle Swarm Optimization Techniques for Error Optimization of Machine Vision Based Tool Movements

NASA Astrophysics Data System (ADS)

Mahapatra, Prasant Kumar; Sethi, Spardha; Kumar, Amod

2015-10-01

In conventional tool positioning technique, sensors embedded in the motion stages provide the accurate tool position information. In this paper, a machine vision based system and image processing technique for motion measurement of lathe tool from two-dimensional sequential images captured using charge coupled device camera having a resolution of 250 microns has been described. An algorithm was developed to calculate the observed distance travelled by the tool from the captured images. As expected, error was observed in the value of the distance traversed by the tool calculated from these images. Optimization of errors due to machine vision system, calibration, environmental factors, etc. in lathe tool movement was carried out using two soft computing techniques, namely, artificial immune system (AIS) and particle swarm optimization (PSO). The results show better capability of AIS over PSO.

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

PubMed

Buntrock, Stefan

2012-01-01

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

[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

Iterative metal artifact reduction: evaluation and optimization of technique.

PubMed

Subhas, Naveen; Primak, Andrew N; Obuchowski, Nancy A; Gupta, Amit; Polster, Joshua M; Krauss, Andreas; Iannotti, Joseph P

2014-12-01

Iterative metal artifact reduction (IMAR) is a sinogram inpainting technique that incorporates high-frequency data from standard weighted filtered back projection (WFBP) reconstructions to reduce metal artifact on computed tomography (CT). This study was designed to compare the image quality of IMAR and WFBP in total shoulder arthroplasties (TSA); determine the optimal amount of WFBP high-frequency data needed for IMAR; and compare image quality of the standard 3D technique with that of a faster 2D technique. Eight patients with nine TSA underwent CT with standardized parameters: 140 kVp, 300 mAs, 0.6 mm collimation and slice thickness, and B30 kernel. WFBP, three 3D IMAR algorithms with different amounts of WFBP high-frequency data (IMARlo, lowest; IMARmod, moderate; IMARhi, highest), and one 2D IMAR algorithm were reconstructed. Differences in attenuation near hardware and away from hardware were measured and compared using repeated measures ANOVA. Five readers independently graded image quality; scores were compared using Friedman's test. Attenuation differences were smaller with all 3D IMAR techniques than with WFBP (p < 0.0063). With increasing high-frequency data, the attenuation difference increased slightly (differences not statistically significant). All readers ranked IMARmod and IMARhi more favorably than WFBP (p < 0.05), with IMARmod ranked highest for most structures. The attenuation difference was slightly higher with 2D than with 3D IMAR, with no significant reader preference for 3D over 2D. IMAR significantly decreases metal artifact compared to WFBP both objectively and subjectively in TSA. The incorporation of a moderate amount of WFBP high-frequency data and use of a 2D reconstruction technique optimize image quality and allow for relatively short reconstruction times.

Eversion-Inversion Labral Repair and Reconstruction Technique for Optimal Suction Seal.

PubMed

Moreira, Brett; Pascual-Garrido, Cecilia; Chadayamurri, Vivek; Mei-Dan, Omer

2015-12-01

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.

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

Surgical management of gynecomastia: experience of a general surgery center

PubMed Central

LONGHEU, A.; MEDAS, F.; CORRIAS, F.; FARRIS, S.; TATTI, A.; PISANO, G.; ERDAS, E.; CALÒ, P.G.

2016-01-01

Aim Gynecomastia is a common finding in male population of all ages. The aim of our study was to present our experience and goals in surgical treatment of gynecomastia. Patients and Methods Clinical records of patients affected by gynecomastia referred to our Department of Surgery between September 2008 and January 2015 were analyzed. 50 patients were included in this study. Results Gynecomastia was monolateral in 12 patients (24%) and bilateral in 38 (76%); idiopathic in 41 patients (82%) and secondary in 9 (18%). 39 patients (78%) underwent surgical operation under general anaesthesia, 11 (22%) under local anaesthesia. 3 patients (6%) presented recurrent disease. Webster technique was performed in 28 patients (56%), Davidson technique in 16 patients (32%); in 2 patients (4%) Pitanguy technique was performed and in 4 patients (8%) a mixed surgical technique was performed. Mean surgical time was 80.72±35.14 minutes, median postoperative stay was 1.46±0.88 days. 2 patients (4%) operated using Davidson technique developed a hematoma, 1 patient (2%) operated with the same technique developed hypertrophic scar. Conclusions Several surgical techniques are described for surgical correction of gynecomastia. If performed by skilled general surgeons surgical treatment of gynecomastia is safe and permits to reach satisfactory aesthetic results. PMID:27938530

Surgical management of gynecomastia: experience of a general surgery center.

PubMed

Longheu, A; Medas, F; Corrias, F; Farris, S; Tatti, A; Pisano, G; Erdas, E; Calò, P G

2016-01-01

Gynecomastia is a common finding in male population of all ages. The aim of our study was to present our experience and goals in surgical treatment of gynecomastia. Clinical records of patients affected by gynecomastia referred to our Department of Surgery between September 2008 and January 2015 were analyzed. 50 patients were included in this study. Gynecomastia was monolateral in 12 patients (24%) and bilateral in 38 (76%); idiopathic in 41 patients (82%) and secondary in 9 (18%). 39 patients (78%) underwent surgical operation under general anaesthesia, 11 (22%) under local anaesthesia. 3 patients (6%) presented recurrent disease. Webster technique was performed in 28 patients (56%), Davidson technique in 16 patients (32%); in 2 patients (4%) Pitanguy technique was performed and in 4 patients (8%) a mixed surgical technique was performed. Mean surgical time was 80.72±35.14 minutes, median postoperative stay was 1.46±0.88 days. 2 patients (4%) operated using Davidson technique developed a hematoma, 1 patient (2%) operated with the same technique developed hypertrophic scar. Several surgical techniques are described for surgical correction of gynecomastia. If performed by skilled general surgeons surgical treatment of gynecomastia is safe and permits to reach satisfactory aesthetic results.

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

PubMed

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

2018-01-01

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

Surgical implantation of transmitters into fish

USGS Publications Warehouse

Mulcahy, Daniel M.

2003-01-01

Although the Animal Welfare Act does not cover poikilotherms, individual institutions and policies and legal requirements other than the Animal Welfare Act (e.g., the US Public Health Service and the Interagency Research Animal Committee's Principles for the Utilization and Care of Vertebrate Animals Used in Testing, Research, and Training) require the review of projects involving fish by institutional animal care and use committees (IACUCs). IACUCs may, however, lack the knowledge and experience to evaluate fish projects judiciously, especially when the projects are in field settings. Surgeries involving implantation of transmitters and other instruments into the coelom, which now comprise a very common research tool in the study of free-ranging fishes, are examples of surgeries that use a broad spectrum of surgical and anesthetic techniques, some of which would not be considered acceptable for similar work on mammals. IACUCs should apply the standards they would expect to be used for surgeries on homeotherms to surgeries on fish. Surgeons should be carefully trained and experienced. Surgical instruments and transmitters should be sterile. Regulations and laws on the use of drugs in animals should be followed, particularly those concerned with anesthetics and antibiotics used on free-ranging fish. Exceptions to surgical procedures should be made only when circumstances are extreme enough to warrant the use of less than optimal procedures.

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.

Knee fusion--a new technique using an old Belgian surgical approach and a new intramedullary nail.

PubMed

Alt, V; Seligson, D

2001-02-01

Knee arthrodesis is a useful procedure in difficult cases such as failed total knee arthroplasty, severe articular trauma, bone tumors, and infected knee joints. The most common techniques for knee fusion include external fixation and intramedullary nailing. Küntscher's nail is driven antegrade from the intertrochanteric region into the knee. We describe a new technique for knee arthrodesis using a new intramedullary nail and an old Belgian surgical approach to the knee joint published by Lambotte in 1913. This approach provides excellent exposure for the implantation of the nail by osteotomizing the patella vertically. The nail is implanted using HeyGroves method, whereby the nail is inserted retrograde into the femur and pulled distally anterograde into the tibia. We now use this technique as our standard procedure for knee fusion.

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

PubMed

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

2008-01-01

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

[Urinary tract involvement by endometriosis. Techniques and outcomes of surgical management: CNGOF-HAS Endometriosis Guidelines].

PubMed

Bolze, P-A; Paparel, P; Golfier, F

2018-03-01

Urinary tract involvement by endometriosis is reported in 1% of endometriosis patients (NP3). Consequences range from pelvic pain for bladder localizations to silent kidney loss in case of chronic ureteral obstruction (NP3). The feasibility of laparoscopic management was widely proven (NP3) and may reduce hospital stay length (NP4). Radical surgery with partial cystectomy for bladder localizations was shown to significantly and durably reduce pain symptoms with low risk of a severe postoperative complications (NP3). Medical hormonal treatment also shows short-term reduction of pain symptoms (NP4). Transureteral resection of bladder endometriosis nodule is not recommended (grade C) because of a high postoperative recurrence rate (NP4). Given a high risk of silent kidney loss, it is recommended that patients with ureteral involvement by endometriosis are managed by a multidisciplinary team considering urinary and potential extra-urinary localizations of endometriosis (grade C). No recommendation can be made on which technique to prefer between conservative (ureterolysis) or radical surgical techniques or on benefit and length of ureteral stents in case of ureteral involvement. Surgical management of bladder and ureteral localizations of endometriosis do not seem to be associated with altered or improved postoperative fertility (NP4). Since late postoperative ureteral anastomosis stenosis were reported with silent kidney loss, repeated postoperative imaging monitoring is justified (expert opinion). Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Hybrid Technique for Cranial Defect Reconstruction: Surgical Results over a 10-Year Period in a Single Institution.

PubMed

Guerrero-Suarez, Pablo David; Guerrero-López, Paola; Ortiz-Leon, Abarin; Sosa-Castillo, Haydee Samantha; Velazquez-Gonzalez, Lenny Marlene; Martinez-Anda, Jaime Jesus

2018-06-11

Decompressive craniectomy is an urgent procedure that is increasingly used for treatment of intracranial hypertension. After recovery, reconstruction of the cranial defect is necessary. Cranioplasty is an elective procedure with a high potential for morbidity if care is not taken on different surgical factors such as the material used as the cranial flap. In Latin America, high costs in some materials used in cranioplasty make its use prohibitive for some patients and institutions, and looking for alternatives has become a priority in neurosurgical centers. An autologous bone flap is an excellent option possessing the characteristics of an ideal material for cranioplasty. Nevertheless, its use is associated with high morbidity and flap failure. We report our mono-institutional experience in a 10-year period of a hybrid technique for cranioplasty using an autologous bone flap with titanium plates. Sixty-five patients underwent the technique, with good cosmetic results in 89.2% and success in functional result in 90.8% of patients . No significant statistical differences were found on the timing of the surgery or the location of the cranial defect. We had a 1.5% rate of surgical site infection, less than that reported on previous series. We propose that the hybrid technique of cranioplasty is a safety and effective option for cranial defect reconstruction. Georg Thieme Verlag KG Stuttgart · New York.

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

PubMed

Parslow, A; Simpson, D J

2017-06-01

A very limited safe anatomical window for transiliosacral implant placement exists in cats (<0·5 cm 2 ). Lag screw fixation requires multiple bilateral implants thus increasing the risk of iatrogenic trauma and implant interference. We describe a safe and effective method for bilateral sacroiliac fixation in cats using a single implant to minimise inadvertent iatrogenic damage to local structures and restore pelvic canal diameter. Eight cats underwent surgical fixation for traumatic bilateral sacroiliac luxation using a single smooth intramedullary pin. The pin spanned both ilial wings and sacrum. Implants were applied using a Universal C-guide. Pre- and postsurgery pelvic canal diameter ratios were calculated. Short-term follow-up was performed at 10 to 14 days postoperatively. Long-term follow-up was performed using the Feline Musculoskeletal Pain Index Questionnaire. Long-term radiographic assessment was available in two cases. The technique achieved safe and accurate implant position with precise sacroiliac joint reduction. Pelvic canal diameter ratios were restored to normal in all cases. Rapid return to normal hind leg function and excellent long-term clinical outcomes were achieved. This technique offers a simple, safe, repeatable and affordable technique for treating bilateral sacroiliac luxations in the cat without the aid of fluoroscopy. The procedure can be performed using surgical tools and inventory readily available in general small animal practices. © 2017 British Small Animal Veterinary Association.

Different methodologies for sustainability of optimization techniques used in submerged and solid state fermentation.

PubMed

Ashok, Anup; Kumar, Devarai Santhosh

2017-10-01

Optimization techniques are considered as a part of nature's way of adjusting to the changes happening around it. There are different factors that establish the optimum working condition or the production of any value-added product. A model is accepted for a particular process after its sustainability has been verified on a statistical and analytical level. Optimization techniques can be divided into categories as statistical, nature inspired and artificial neural network each with its own benefits and usage in particular cases. A brief introduction about subcategories of different techniques that are available and their computational effectivity will be discussed. The main focus of the study revolves around the applicability of these techniques to any particular operation such as submerged fermentation (SmF) and solid state fermentation (SSF), their ability to produce secondary metabolites and the usefulness in the laboratory and industrial level. Primary studies to determine the enzyme activity of different microorganisms such as bacteria, fungi and yeast will also be discussed. l-Asparaginase, the most commonly used drugs in the treatment of acute lymphoblastic leukemia (ALL) shall be considered as an example, a short discussion on models used in the production by the processes of SmF and SSF will be discussed to understand the optimization techniques that are being dealt. It is expected that this discussion would help in determining the proper technique that can be used in running any optimization process for different purposes, and would help in making these processes less time-consuming with better output.

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

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.

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.

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

How to Avoid a Learning Curve in Stapedotomy: A Standardized Surgical Technique.

PubMed

Kwok, Pingling; Gleich, Otto; Dalles, Katharina; Mayr, Elisabeth; Jacob, Peter; Strutz, Jürgen

2017-08-01

To evaluate, whether a learning curve for beginners in stapedotomy can be avoided by using a prosthesis with thermal memory-shape attachment in combination with a standardized laser-assisted surgical technique. Retrospective case review. Tertiary referral center. Fifty-eight ears were operated by three experienced surgeons and compared with a group of 12 cases operated by a beginner in stapedotomy. Stapedotomy. Difference of pure-tone audiometry thresholds measured before and after surgery. The average postoperative gain for air conduction in the frequencies below 2 kHz was 20 to 25 dB and decreased for the higher frequencies. Using the Mann-Whitney-U test for comparing mean gain between experienced and inexperienced surgeons showed no significant difference (p = 0.281 at 4 kHz and p > 0.7 for the other frequencies). A Spearman rank correlation of the postoperative gain for air- and bone-conduction thresholds was obtained at each test frequency for the first 12 patients consecutively treated with a thermal memory-shape attachment prosthesis by two experienced and one inexperienced surgeon. This analysis does not support the hypothesis of a "learning effect" that should be associated with an improved outcome for successively treated patients. It is possible to avoid a learning curve in stapes surgery by applying a thermal memory-shape prosthesis in a standardized laser-assisted surgical procedure.

A method of pre-surgical oral orthopaedics.

PubMed

DiBiase, D D; Hunter, S B

1983-01-01

A preliminary report of a technique of pre-surgical treatment in cleft lip and palate patients is outlined utilizing an adjustable intra-oral appliance with extra-oral strapping. The appliance is constructed with an adjustable spring for expansion and two shelves overlapping in the midline to allow palatal continuity during treatment. Frequently, only one appliance for each patient is required. The techniques of appliance construction, pre-surgical management and surgical repair of the lip are outlined.

Surgical management of venous malformations.

PubMed

Loose, D A

2007-01-01

Among vascular malformations, the predominantly venous malformations represent the majority of cases. They form a clinical entity and therefore need clear concepts concerning diagnosis and treatment. This paper presents an overview of contemporary classification as well as tactics and techniques of treatment. According to the Hamburg Classification, predominantly venous malformations are categorized into truncular and extratruncular forms, with truncular forms distinguished as obstructions and dilations, and extratruncular forms as limited or infiltrating. The tactics of treatment represent surgical and non-surgical methods or combined techniques. Surgical approaches utilize different tactics and techniques that are adopted based on the pathologic form and type of the malformation: (I) operation to reduce the haemodynamic activity of the malformation; (II) operation to eliminate the malformation; and (III) reconstructive operation. As for (I), a type of a tactic is the operation to derive the venous flow. In (II), the total or partial removal of the venous malformation is demonstrated subdivided into three different techniques. In this way, the infiltrating as well as the limited forms can be treated. An additional technique is dedicated to the treatment of a marginal vein. Approach (III) involves the treatment of venous aneurysms, where a variety of techniques have been successful. Long-term follow-up demonstrates positive results in 91% of the cases. Congenital predominantly venous malformations should be treated according to the principles developed during the past decades in vascular surgery, interventional treatment and multidisciplinary treatment. The days of predominantly conservative treatment should be relegated to the past. Special skills and experiences are necessary to carry out appropriate surgical strategy, and the required operative techniques should be dictated by the location and type of malformation and associated findings.

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

PubMed

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

2018-06-01

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

[Diverticular disease of the large bowel - surgical treatment].

PubMed

Levý, M; Herdegen, P; Sutoris, K; Simša, J

2013-07-01

Surgical treatment, despite the rapid development of the numerous modern miniinvasive intervention techniques, remains essential in the treatment of complicated diverticular disease. The aim of this work is to summarize indications for surgical treatment in both acute and elective patients suffering from diverticular disease of the large bowel. Review of the literature and recent findings concerning indications for surgical intervention in patients with diverticulosis of the colon. The article describes indications, types of procedures, techniques and postoperative care in patients undergoing surgical intervention for diverticular disease.

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.

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.

Optimization techniques applied to spectrum management for communications satellites

NASA Astrophysics Data System (ADS)

Ottey, H. R.; Sullivan, T. M.; Zusman, F. S.

This paper describes user requirements, algorithms and software design features for the application of optimization techniques to the management of the geostationary orbit/spectrum resource. Relevant problems include parameter sensitivity analyses, frequency and orbit position assignment coordination, and orbit position allotment planning. It is shown how integer and nonlinear programming as well as heuristic search techniques can be used to solve these problems. Formalized mathematical objective functions that define the problems are presented. Constraint functions that impart the necessary solution bounds are described. A versatile program structure is outlined, which would allow problems to be solved in stages while varying the problem space, solution resolution, objective function and constraints.

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.

Multispectral tissue characterization for intestinal anastomosis optimization

PubMed Central

Cha, Jaepyeong; Shademan, Azad; Le, Hanh N. D.; Decker, Ryan; Kim, Peter C. W.; Kang, Jin U.; Krieger, Axel

2015-01-01

Abstract. Intestinal anastomosis is a surgical procedure that restores bowel continuity after surgical resection to treat intestinal malignancy, inflammation, or obstruction. Despite the routine nature of intestinal anastomosis procedures, the rate of complications is high. Standard visual inspection cannot distinguish the tissue subsurface and small changes in spectral characteristics of the tissue, so existing tissue anastomosis techniques that rely on human vision to guide suturing could lead to problems such as bleeding and leakage from suturing sites. We present a proof-of-concept study using a portable multispectral imaging (MSI) platform for tissue characterization and preoperative surgical planning in intestinal anastomosis. The platform is composed of a fiber ring light-guided MSI system coupled with polarizers and image analysis software. The system is tested on ex vivo porcine intestine tissue, and we demonstrate the feasibility of identifying optimal regions for suture placement. PMID:26440616

VirSSPA- a virtual reality tool for surgical planning workflow.

PubMed

Suárez, C; Acha, B; Serrano, C; Parra, C; Gómez, T

2009-03-01

A virtual reality tool, called VirSSPA, was developed to optimize the planning of surgical processes. Segmentation algorithms for Computed Tomography (CT) images: a region growing procedure was used for soft tissues and a thresholding algorithm was implemented to segment bones. The algorithms operate semiautomati- cally since they only need seed selection with the mouse on each tissue segmented by the user. The novelty of the paper is the adaptation of an enhancement method based on histogram thresholding applied to CT images for surgical planning, which simplifies subsequent segmentation. A substantial improvement of the virtual reality tool VirSSPA was obtained with these algorithms. VirSSPA was used to optimize surgical planning, to decrease the time spent on surgical planning and to improve operative results. The success rate increases due to surgeons being able to see the exact extent of the patient's ailment. This tool can decrease operating room time, thus resulting in reduced costs. Virtual simulation was effective for optimizing surgical planning, which could, consequently, result in improved outcomes with reduced costs.

Computer-based planning of optimal donor sites for autologous osseous grafts

NASA Astrophysics Data System (ADS)

Krol, Zdzislaw; Chlebiej, Michal; Zerfass, Peter; Zeilhofer, Hans-Florian U.; Sader, Robert; Mikolajczak, Pawel; Keeve, Erwin

2002-05-01

Bone graft surgery is often necessary for reconstruction of craniofacial defects after trauma, tumor, infection or congenital malformation. In this operative technique the removed or missing bone segment is filled with a bone graft. The mainstay of the craniofacial reconstruction rests with the replacement of the defected bone by autogeneous bone grafts. To achieve sufficient incorporation of the autograft into the host bone, precise planning and simulation of the surgical intervention is required. The major problem is to determine as accurately as possible the donor site where the graft should be dissected from and to define the shape of the desired transplant. A computer-aided method for semi-automatic selection of optimal donor sites for autografts in craniofacial reconstructive surgery has been developed. The non-automatic step of graft design and constraint setting is followed by a fully automatic procedure to find the best fitting position. In extension to preceding work, a new optimization approach based on the Levenberg-Marquardt method has been implemented and embedded into our computer-based surgical planning system. This new technique enables, once the pre-processing step has been performed, selection of the optimal donor site in time less than one minute. The method has been applied during surgery planning step in more than 20 cases. The postoperative observations have shown that functional results, such as speech and chewing ability as well as restoration of bony continuity were clearly better compared to conventionally planned operations. Moreover, in most cases the duration of the surgical interventions has been distinctly reduced.

"Enteroatmospheric fistulae"--gastrointestinal openings in the open abdomen: a review and recent proposal of a surgical technique.

PubMed

Marinis, A; Gkiokas, G; Argyra, E; Fragulidis, G; Polymeneas, G; Voros, D

2013-01-01

The occurrence of an enteric fistula in the middle of an open abdomen is called an enteroatmospheric fistula, which is the most challenging and feared complication for a surgeon to deal with. It is in fact not a true fistula because it neither has a fistula tract nor is covered by a well-vascularized tissue. The mortality of enteroatmospheric fistulae was as high as 70% in past decades but is currently approximately 40% due to advanced modern intensive care and improved surgical techniques. Management of patients with an open abdomen and an enteroatmospheric fistula is very challenging. Intensive care support of organs and systems is vital in order to manage the severely septic patient and the associated multiple organ failure syndrome. Many of the principles applied to classic enterocutaneous fistulae are used as well. Control of enteric spillage, attempts to seal the fistula, and techniques of peritoneal access for excision of the involved loop are reviewed in this report. Additionally, we describe our recent proposal of a lateral surgical approach via the circumference of the open abdomen in order to avoid the hostile and granulated surface of the abdominal trauma, which is adhered to the intraperitoneal organs.

Traumatic Extensor Tendon Injuries to the Hand: Clinical Anatomy, Biomechanics, and Surgical Procedure Review.

PubMed

Colzani, Giulia; Tos, Pierluigi; Battiston, Bruno; Merolla, Giovanni; Porcellini, Giuseppe; Artiaco, Stefano

2016-04-01

The extensor apparatus is a complex muscle-tendon system that requires integrity or optimal reconstruction to preserve hand function. Anatomical knowledge and the understanding of physiopathology of extensor tendons are essential for an accurate diagnosis of extensor tendon injuries (ETIs) of the hand and wrist, because these lesions are complex and commonly observed in clinical practice. A careful clinical history and assessment still remain the first step for the diagnosis, followed by US and MR to confirm the suspect of ETI or to investigate some doubtful conditions and rule out associate lesions. During last decades the evolution of surgical techniques and rehabilitative treatment protocol led to gradual improvement in clinical results of ETI treatment and surgical repair. Injury classification into anatomical zones and the evaluation of the characteristics of the lesions are considered key points to select the appropriate treatment for ETI. Both conservative and surgical management can be indicated in ETI, depending on the anatomical zone and on the characteristics of the injuries. As a general rule, an attempt of conservative treatment should be performed when the lesion is expected to have favorable result with nonoperative procedure. Many surgical techniques have been proposed over the time and with favorable results if the tendon injury is not underestimated and adequately treated. Despite recent research findings, a lack of evidence-based knowledge is still observed in surgical treatment and postoperative management of ETI. Further clinical and biomechanical investigations would be advisable to clarify this complex issue.

Traumatic Extensor Tendon Injuries to the Hand: Clinical Anatomy, Biomechanics, and Surgical Procedure Review

PubMed Central

Colzani, Giulia; Tos, Pierluigi; Battiston, Bruno; Merolla, Giovanni; Porcellini, Giuseppe; Artiaco, Stefano

2016-01-01

The extensor apparatus is a complex muscle-tendon system that requires integrity or optimal reconstruction to preserve hand function. Anatomical knowledge and the understanding of physiopathology of extensor tendons are essential for an accurate diagnosis of extensor tendon injuries (ETIs) of the hand and wrist, because these lesions are complex and commonly observed in clinical practice. A careful clinical history and assessment still remain the first step for the diagnosis, followed by US and MR to confirm the suspect of ETI or to investigate some doubtful conditions and rule out associate lesions. During last decades the evolution of surgical techniques and rehabilitative treatment protocol led to gradual improvement in clinical results of ETI treatment and surgical repair. Injury classification into anatomical zones and the evaluation of the characteristics of the lesions are considered key points to select the appropriate treatment for ETI. Both conservative and surgical management can be indicated in ETI, depending on the anatomical zone and on the characteristics of the injuries. As a general rule, an attempt of conservative treatment should be performed when the lesion is expected to have favorable result with nonoperative procedure. Many surgical techniques have been proposed over the time and with favorable results if the tendon injury is not underestimated and adequately treated. Despite recent research findings, a lack of evidence-based knowledge is still observed in surgical treatment and postoperative management of ETI. Further clinical and biomechanical investigations would be advisable to clarify this complex issue. PMID:27616821

[Clinical application of Da Vinci surgical system in China].

PubMed

Jin, Zhenyu

2014-01-01

Da Vinci robotic surgical system leads the development of minimally invasive surgical techniques. By using Da Vinci surgical robot for minimally invasive surgery, it brings a lot of advantages to the surgeons. Since 2008, Da Vinci surgeries have been performed in 14 hospitals in domestic cities such as Beijing and Shanghai. Until the end of 2012, 3 551 cases of Da Vinci robotic surgery have been performed, covering various procedures of various surgical departments including the department of general surgery, urology, cardiovascular surgery, thoracic surgery, gynecology, and etc. Robotic surgical technique has made remarkable achievements.

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

PubMed

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

2016-07-01

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

Minimal invasive epicardial lead implantation: optimizing cardiac resynchronization with a new mapping device for epicardial lead placement.

PubMed

Maessen, J G; Phelps, B; Dekker, A L A J; Dijkman, B

2004-05-01

To optimize resynchronization in biventricular pacing with epicardial leads, mapping to determine the best pacing site, is a prerequisite. A port access surgical mapping technique was developed that allowed multiple pace site selection and reproducible lead evaluation and implantation. Pressure-volume loops analysis was used for real time guidance in targeting epicardial lead placement. Even the smallest changes in lead position revealed significantly different functional results. Optimizing the pacing site with this technique allowed functional improvement up to 40% versus random pace site selection.

[Surgical treatment of varicose vein using the tumescent technique of local anesthesia].

PubMed

Bjelanović, Zoran; Leković, Ivan; Drasković, Miroljub; Misović, Sidor; Veljović, Milić

2011-02-01

Tumescent local anesthesia (TLA) is a technique for local and regional anesthesia of the skin and the subcutaneous tissue, using infiltration of large amounts of a diluted solution of local anesthetic. This technique is applied in plastic surgery, liposuction as well as in dermatology for the entire series of dermatocosmetic procedures. The purpose of this study was to determine efficiency of surgical treatment of varicose vein using TLA as an alternative method to a conventional treatment for varicose vein. Seventy-two patients with varicose vein were enrolled in the study. All of them were operated on applying TLA, from April 2008 to November 2009. TLA solution consisted of local anesthetics was used. TLA solutions used were: 1% prilocaine-chloride with adrenaline supplement, and 2% lidocaine-chloride and adrenaline in concentration of 0.1%-0.4%. Out of 72 patients, we stripped great saphenous vein from 60 patient and did varicectomy as well as ligation of insufficiently perforating veins. In 12 patients we did partial varicectomy and ligation of perforating veins. There were not any patients with the need for continued surgery, as well as bringing patient to the general anesthesia due to pain during the surgery. One patient came for postoperative opening wound in the groin, one for infection of the wound and one for the formation of seroma in the groin. There were not any allergic reactions or systemic complications in the operations as well as postoperative period. Postoperatively, all the patients were treated with compressive elastic bandage during the period of 6 weeks as well as anticoagulation prophylaxis in the duration of 5 days. Surgery of varicose veins with implementation of TLA is easy and safe method with very low percentage of complications and unwanted effects. It is a good alternative method to classic surgery of varicose veins. The economic aspect is a very important component because the cost of this method is significantly lower than that of a

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

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. Copyright © 2015 Elsevier Inc. All rights reserved.

Achilles tendon rupture: physiotherapy and endoscopy-assisted surgical treatment of a common sports injury

PubMed Central

Doral, Mahmut Nedim; Bozkurt, Murat; Turhan, Egemen; Dönmez, Gürhan; Demirel, Murat; Kaya, Defne; Ateşok, Kıvanç; Atay, Özgür Ahmet; Maffulli, Nicola

2010-01-01

Although the Achilles tendon (AT) is the strongest tendon in the human body, rupture of this tendon is one of the most common sports injuries in the athletic population. Despite numerous nonoperative and operative methods that have been described, there is no universal agreement about the optimal management strategy of acute total AT ruptures. The management of AT ruptures should aim to minimize the morbidity of the injury, optimize rapid return to full function, and prevent complications. Since endoscopy-assisted percutaneous AT repair allows direct visualization of the synovia and protects the paratenon that is important in biological healing of the AT, this technique becomes a reasonable treatment option in AT ruptures. Furthermore, Achilles tendoscopy technique may decrease the complications about the sural nerve. Also, early functional postoperative physiotherapy following surgery may improve the surgical outcomes. PMID:24198562

Gastrointestinal surgery in gynecologic oncology: evaluation of surgical techniques.

PubMed

Penalver, M; Averette, H; Sevin, B U; Lichtinger, M; Girtanner, R

1987-09-01

In recent years, the use of surgical staples has become popular in all subspecialties of surgery. The advantages proposed have been a decrease in operative time and morbidity. This paper reviews the University of Miami/Jackson Memorial Medical Center, Division of Gynecologic Oncology experience with the use of surgical staples in gastrointestinal surgery on patients with a diagnosis of a gynecologic malignancy. Between January 1, 1979 and July 1, 1985, a total of 152 procedures were done, 81 by stapler and 71 by suture anastomosis. Ninety-one patients had received previous radiation or chemotherapy. The average age of the patients was 52 years. The results show a decrease in operating time, blood loss, and postoperative hospital stay in those patients where the stapler anastomosis was used. The postoperative morbidity and mortality were not increased. Twenty-seven total pelvic exenterations were performed during the period of study and they were evaluated separately. The hospital stay and blood loss as well as the operative time were significantly less using staplers. This report includes a detailed evaluation of the results. From this study, we concluded that surgical staples are a safe alternative in gastrointestinal surgery in patients with a gynecologic malignancy.

Current surgical strategies for total arthroplasty in valgus knee

PubMed Central

Nikolopoulos, Dimitrios; Michos, Ioannis; Safos, George; Safos, Petros

2015-01-01

The majority of orthopaedic surgeons even currently agree that primary total arthroplasty in valgus knees with a deformity of more than ten degrees may prove challenging. The unique sets of bone and soft tissue abnormalities that must be addressed at the time of the operation make accurate axis restoration, component orientation and joint stability attainment a difficult task. Understanding the specific pathologic anatomic changes associated with the valgus knee is a prerequisite so as to select the proper surgical method, to optimize component position and restore soft-tissue balance. The purpose of this article is to review the valgus knee anatomical variations, to assess the best pre-operative planning and to evaluate how to choose the grade of constraint of the implant. It will also be underlying the up-to-date main approaches and surgical techniques be proposed in the English literature both for bone cuts and soft tissue management of valgus knees. PMID:26191494

Novel Surgical Technique for Coronary Fistulas With Proximal Origin.

PubMed

Uchida, Tetsuro; Hamasaki, Azumi; Kuroda, Yoshinori; Ohba, Eiichi; Yamashita, Atsushi; Sadahiro, Mitsuaki

2017-09-01

Postoperative residual shunting is a significant concern in patients with coronary arteriovenous fistulas, especially in fistulas originating from the proximal left coronary artery, because of the limited surgical field. We report a case of fistulas originating from the proximal coronary artery in a 63-year-old woman in whom the ascending aorta and pulmonary artery were transected to obtain good surgical exposure. After complete transection of both great arteries, fistulas arising from the left main trunk were ligated externally, and their intracardiac openings were closed internally. Postoperative examination revealed no residual shunt flow. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

A modified surgical technique in the management of eyelid burns: a case series

PubMed Central

2011-01-01

Introduction Contractures, ectropion and scarring, the most common sequelae of skin grafts after eyelid burn injuries, can result in corneal exposure, corneal ulceration and even blindness. Split-thickness or full-thickness skin grafts are commonly used for the treatment of acute eyelid burns. Plasma exudation and infection are common early complications of eyelid burns, which decrease the success rate of grafts. Case presentation We present the cases of eight patients, two Chinese women and six Chinese men. The first Chinese woman was 36 years old, with 70% body surface area second or third degree flame burn injuries involving her eyelids on both sides. The other Chinese woman was 28 years old, with sulfuric acid burns on her face and third degree burn on her eyelids. The six Chinese men were aged 21, 31, 38, 42, 44, and 55 years, respectively. The 38-year-old patient was transferred from the ER with 80% body surface area second or third degree flame burn injuries and third degree burn injuries to his eyelids. The other five men were all patients with flame burn injuries, with 7% to 10% body surface area third degree burns and eyelids involved. All patients were treated with a modified surgical procedure consisting of separation and loosening of the musculus orbicularis oculi between tarsal plate and septum orbital, followed by grafting a large full-thickness skin graft in three days after burn injury. The use of our modified surgical procedure resulted in 100% successful eyelid grafting on first attempt, and all our patients were in good condition at six-month follow-up. Conclusions This new surgical technique is highly successful in treating eyelid burn injuries, especially flame burn injuries of the eyelid. PMID:21843322

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

USGS Publications Warehouse

Martinelli, Theresa 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

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. © 2010 National Association for Healthcare Quality.

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

PubMed

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

2013-01-01

This study compares the medium-term results of De Vega, modified De Vega, and ring annuloplasty techniques for the correction of tricuspid insufficiency and investigates the risk factors for recurrent grades 3 and 4 tricuspid insufficiency after repair. In our clinic, 93 patients with functional tricuspid insufficiency underwent surgical tricuspid repair from May 2007 through October 2010. The study was retrospective, and all the data pertaining to the patients were retrieved from hospital records. Functional capacity, recurrent tricuspid insufficiency, and risk factors aggravating the insufficiency were analyzed for each patient. In the medium term (25.4 ± 10.3 mo), the rates of grades 3 and 4 tricuspid insufficiency in the De Vega, modified De Vega, and ring annuloplasty groups were 31%, 23.1%, and 6.1%, respectively. Logistic regression analysis revealed that chronic obstructive pulmonary disease, left ventricular dysfunction (ejection fraction, < 0.50), pulmonary artery pressure ≥60 mmHg, and the De Vega annuloplasty technique were risk factors for medium-term recurrent grades 3 and 4 tricuspid insufficiency. Medium-term survival was 90.6% for the De Vega group, 96.3% for the modified De Vega group, and 97.1% for the ring annuloplasty group. Ring annuloplasty provided the best relief from recurrent tricuspid insufficiency when compared with DeVega annuloplasty. Modified De Vega annuloplasty might be a suitable alternative to ring annuloplasty when rings are not available.

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

PubMed Central

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

2013-01-01

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

Comparison among the levels of patients' satisfaction according to the surgical technique used in breast reconstruction after mastectomy.

PubMed

Gómez-Escolar Larrañaga, Lucía; Delgado Martínez, Julio; Miguelena Bobadilla, José María

2017-12-01

It has been proved that a breast reconstruction after a mastectomy has a great psycho-social impact on patients. For this reason, it is increasingly done in a greater percentage of cases. There are two major groups of reconstructive techniques: a reconstruction with implants and a reconstruction with autologous tissue of the patient. In order to make a more objective assessment of the results, it is important to know how satisfied these patients are with the results. Therefore, we performed a study using Q-BREAST, the aim of which is to analyze the satisfaction of mastectomized patients according to the different surgical reconstruction techniques. A retrospective, descriptive and observational study of patients reconstructed in our service from 2008 to 2011 was carried out. Patient satisfaction levels were compared according to the surgical technique used in breast reconstruction using the Q-BREAST test, which was mailed to them. There are no statistical differences in the levels of satisfaction in terms of age, type of mastectomy done, coadjutant treatment or existence of complications. Higher levels of satisfaction are observed in patients reconstructed with autologous tissue versus implants (P=.028). Patients reconstructed with autologous tissue have higher levels of satisfaction than those reconstructed with implants. Copyright © 2017 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

Surgical Treatment for Chronic Pancreatitis: Past, Present, and Future

PubMed Central

Welte, Maria; Izbicki, Jakob R.; Bachmann, Kai

2017-01-01

The pancreas was one of the last explored organs in the human body. The first surgical experiences were made before fully understanding the function of the gland. Surgical procedures remained less successful until the discovery of insulin, blood groups, and finally the possibility of blood donation. Throughout the centuries, the surgical approach went from radical resections to minimal resections or only drainage of the gland in comparison to an adequate resection combined with drainage procedures. Today, the well-known and standardized procedures are considered as safe due to the high experience of operating surgeons, the centering of pancreatic surgery in specialized centers, and optimized perioperative treatment. Although surgical procedures have become safer and more efficient than ever, the overall perioperative morbidity after pancreatic surgery remains high and management of postoperative complications stagnates. Current research focuses on the prevention of complications, optimizing the patient's general condition preoperatively and finding the appropriate timing for surgical treatment. PMID:28819358

Parallel halftoning technique using dot diffusion optimization

NASA Astrophysics Data System (ADS)

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

2017-05-01

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

An image morphing technique based on optimal mass preserving mapping.

PubMed

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

2007-06-01

Image morphing, or image interpolation in the time domain, deals with the metamorphosis of one image into another. In this paper, a new class of image morphing algorithms is proposed based on the theory of optimal mass transport. The L(2) mass moving energy functional is modified by adding an intensity penalizing term, in order to reduce the undesired double exposure effect. It is an intensity-based approach and, thus, is parameter free. The optimal warping function is computed using an iterative gradient descent approach. This proposed morphing method is also extended to doubly connected domains using a harmonic parameterization technique, along with finite-element methods.

An Image Morphing Technique Based on Optimal Mass Preserving Mapping

PubMed Central

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

2013-01-01

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

Staged marginal contoured and central excision technique in the surgical management of perianal Paget's disease.

PubMed

Möller, Mecker G; Lugo-Baruqui, Jose Alejandro; Milikowski, Clara; Salgado, Christopher J

2014-04-01

Extramammary Paget's disease (EMPD) is an adenocarcinoma of the apocrine glands with unknown exact prevalence and obscure etiology. It has been divided into primary EMPD and secondary EMPD, in which an internal malignancy is usually associated. Treatment for primary EMPD usually consists of wide lesion excision with negative margins. Multiple methods have been proposed to obtain free-margin status of the disease. These include visible border lesion excision, punch biopsies, and micrographic and frozen-section surgery, with different results but still high recurrence rates. The investigators propose a method consisting of a staged contoured marginal excision using "en face" permanent pathologic analysis preceding the steps of central excision of the lesion and the final reconstruction of the surgical defect. Advantages of this method include adequate margin control allowing final reconstruction and tissue preservation, while minimizing patient discomfort. The staged contoured marginal and central excision technique offers a new alternative to the armamentarium for surgical oncologists for the management of EMPD in which margin control is imperative for control of recurrence rates. Copyright © 2014 Elsevier Inc. All rights reserved.

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. Copyright © 2016. Published by Elsevier Ltd.

Dermatologic Surgical Instruments: A History and Review.

PubMed

Gandhi, Sumul A; Kampp, Jeremy T

2017-01-01

Dermatologic surgery requires precision and accuracy given the delicate nature of procedures performed. The use of the most appropriate instrument for each action helps optimize both functionality and cosmetic outcome. To review the history of surgical instruments used in dermatology, with a focus on mechanism and evolution to the instruments that are used in current practice. A comprehensive literature search was conducted via textbook and journal research for historic references while review of current references was conducted online using multiple search engines and PubMed. There are a number of articles that review instruments in dermatology, but this article adds a unique perspective in classifying their evolution, while also presenting them as levers that serve to increase human dexterity during the course of surgery. Surgical instruments allow fine manipulation of tissue, which in turn produces optimal outcomes. Surgical tools have been around since the dawn of man, and their evolution parallels the extent to which human civilization has specialized over time. This article describes the evolution of instruments from the general surgical armamentaria to the specialized tools that are used today.

A Survey on Optimal Signal Processing Techniques Applied to Improve the Performance of Mechanical Sensors in Automotive Applications

PubMed Central

Hernandez, Wilmar

2007-01-01

In this paper a survey on recent applications of optimal signal processing techniques to improve the performance of mechanical sensors is made. Here, a comparison between classical filters and optimal filters for automotive sensors is made, and the current state of the art of the application of robust and optimal control and signal processing techniques to the design of the intelligent (or smart) sensors that today's cars need is presented through several experimental results that show that the fusion of intelligent sensors and optimal signal processing techniques is the clear way to go. However, the switch between the traditional methods of designing automotive sensors and the new ones cannot be done overnight because there are some open research issues that have to be solved. This paper draws attention to one of the open research issues and tries to arouse researcher's interest in the fusion of intelligent sensors and optimal signal processing techniques.

Imaging technique for the complete edentulous patient treated conventionally or with mini implant overdenture

PubMed Central

Meleşcanu Imre, M; Preoteasa, E; Țâncu, AM; Preoteasa, CT

2013-01-01

Rationale. The imaging methods are more and more used in the clinical process of modern dentistry. Once the implant based treatment alternatives are nowadays seen as being the standard of care in edentulous patients, these techniques must be integrated in the complete denture treatment. Aim. The study presents some evaluation techniques for the edentulous patient treated by conventional dentures or mini dental implants (mini SKY Bredent) overdentures, using the profile teleradiography. These offer data useful for an optimal positioning of the artificial teeth and the mini dental implants, favoring to obtain an esthetic and functional treatment outcome. We proposed also a method to conceive a simple surgical guide that allows the prosthetically driven implants placement. Material and method. Clinical case reports were made, highlighting the importance of cephalometric evaluation on lateral teleradiographs in complete edentulous patients. A clinical case that gradually reports the surgical guide preparation (Bredent silicon radio opaque), in order to place the mini dental implants in the best prosthetic and anatomic conditions, was presented. Conclusions. The profile teleradiograph is a useful tool for the practitioner. It allows establishing the optimal site for implant placement, in a good relation with the overdenture. The conventional denture can be easily and relatively costless transformed in a surgical guide used during implant placement. PMID:23599828

[Preparation of simulate craniocerebral models via three dimensional printing technique].

PubMed

Lan, Q; Chen, A L; Zhang, T; Zhu, Q; Xu, T

2016-08-09

Three dimensional (3D) printing technique was used to prepare the simulate craniocerebral models, which were applied to preoperative planning and surgical simulation. The image data was collected from PACS system. Image data of skull bone, brain tissue and tumors, cerebral arteries and aneurysms, and functional regions and relative neural tracts of the brain were extracted from thin slice scan (slice thickness 0.5 mm) of computed tomography (CT), magnetic resonance imaging (MRI, slice thickness 1mm), computed tomography angiography (CTA), and functional magnetic resonance imaging (fMRI) data, respectively. MIMICS software was applied to reconstruct colored virtual models by identifying and differentiating tissues according to their gray scales. Then the colored virtual models were submitted to 3D printer which produced life-sized craniocerebral models for surgical planning and surgical simulation. 3D printing craniocerebral models allowed neurosurgeons to perform complex procedures in specific clinical cases though detailed surgical planning. It offered great convenience for evaluating the size of spatial fissure of sellar region before surgery, which helped to optimize surgical approach planning. These 3D models also provided detailed information about the location of aneurysms and their parent arteries, which helped surgeons to choose appropriate aneurismal clips, as well as perform surgical simulation. The models further gave clear indications of depth and extent of tumors and their relationship to eloquent cortical areas and adjacent neural tracts, which were able to avoid surgical damaging of important neural structures. As a novel and promising technique, the application of 3D printing craniocerebral models could improve the surgical planning by converting virtual visualization into real life-sized models.It also contributes to functional anatomy study.

[Surgical therapy of gynecomastia].

PubMed

Heckmann, A; Leclère, F M; Vogt, P M; Steiert, A

2011-09-01

Nowadays surgical intervention is an essential part of the treatment of idiopathic gynecomastia. Choosing the right method is crucial and is based on the current status in the clinical and histological evaluation. Before finalizing the process of choosing a specific method a prior interdisciplinary evaluation of the patient is necessary to ascertain clear indications for a surgical intervention. Liposuction is one of the methods which have become popular in recent years. The advantages are the possible combination with traditional techniques, such as subcutaneous mastectomy or periareolar mastopexy. The main indication is for gynecomastia stage IIa/b and is justifiable due to the reduction in surgical complications and scarring. Furthermore this technique provides an excellent aesthetical outcome for the patient. A total of 162 patients suffering from gynecomastia stages I-III (according to Simon) were surgically treated between 2000 and 2010 and these cases were retrospectively evaluated. The results showed a decline in the use of a T-shaped incision in combination with subcutaneous mastectomy with periareolar tightening compared to an increase in the use of subcutaneous mastectomy in combination with liposuction. The excised tissue should always be sent for histological examination to make sure no malignant cells were present.

[Optimization of the pseudorandom input signals used for the forced oscillation technique].

PubMed

Liu, Xiaoli; Zhang, Nan; Liang, Hong; Zhang, Zhengbo; Li, Deyu; Wang, Weidong

2017-10-01

The forced oscillation technique (FOT) is an active pulmonary function measurement technique that was applied to identify the mechanical properties of the respiratory system using external excitation signals. FOT commonly includes single frequency sine, pseudorandom and periodic impulse excitation signals. Aiming at preventing the time-domain amplitude overshoot that might exist in the acquisition of combined multi sinusoidal pseudorandom signals, this paper studied the phase optimization of pseudorandom signals. We tried two methods including the random phase combination and time-frequency domain swapping algorithm to solve this problem, and used the crest factor to estimate the effect of optimization. Furthermore, in order to make the pseudorandom signals met the requirement of the respiratory system identification in 4-40 Hz, we compensated the input signals' amplitudes at the low frequency band (4-18 Hz) according to the frequency-response curve of the oscillation unit. Resuts showed that time-frequency domain swapping algorithm could effectively optimize the phase combination of pseudorandom signals. Moreover, when the amplitudes at low frequencies were compensated, the expected stimulus signals which met the performance requirements were obtained eventually.

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. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

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

PubMed

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

2015-09-01

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

Surgical management of unruptured asymptomatic aneurysms.

PubMed

Samsom, D S; Hodosh, R M; Clark, W K

1977-06-01

The natural history of unruptured asymptomatic aneurysms in nuclear. Because of this uncertainty regarding risk of ultimate enlargement and/or hemorrhage, and in view of the significant mortality and morbidity traditionally involved in aneurysm surgery, clinicans have varied in their advocacy of surgical management of such lesions. Forty-nine consecutive patients harboring 52 such aneurysms were treated surgically over a 57-month period. There were no surgical deaths and morbidity was within acceptable limits. Patient population characteristic and surgical technique are discussed.

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

PubMed

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

2017-10-01

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

Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio-Inspired Optimization Techniques

DTIC Science & Technology

2017-11-01

ARL-TR-8225 ● NOV 2017 US Army Research Laboratory Methodology for Designing and Developing a New Ultra-Wideband Antenna Based...Research Laboratory Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio-Inspired Optimization Techniques by...SUBTITLE Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio-Inspired Optimization Techniques 5a. CONTRACT NUMBER

Scar prevention and remodeling: a review of the medical, surgical, topical and light treatment approaches.

PubMed

Kerwin, Leonard Y; El Tal, Abdel Kader; Stiff, Mark A; Fakhouri, Tarek M

2014-08-01

Cosmetic, functional, and structural sequelae of scarring are innumerable, and measures exist to optimize and ultimately minimize these sequelae. To evaluate the innumerable methods available to decrease the cosmetic, functional, and structural repercussions of scarring, pubMed search of the English literature with key words scar, scar revision, scar prevention, scar treatment, scar remodeling, cicatrix, cicatrix treatment, and cicatrix remodeling was done. Original articles and reviews were examined and included. Seventy-nine manuscripts were reviewed. Techniques, comparisons, and results were reviewed and tabulated. Overall, though topical modalities are easier to use and are usually more attractive to the patient, the surgical approaches still prove to be superior and more reliable. However, advances in topical medications for scar modification are on the rise and a change towards medical treatment of scars may emerge as the next best approach. Comparison studies of the innumerable specific modalities for scar revision and prevention are impossible. Standardization of techniques is lacking. Scarring, the body's natural response to a wound, can create many adverse effects. At this point, the practice of sound, surgical fundamentals still trump the most advanced preventative methods and revision techniques. Advances in medical approaches are available, however, to assist the scarring process, which even the most advanced surgical fundamentals will ultimately lead to. Whether through newer topical therapies, light treatment, or classical surgical intervention, our treatment armamentarium of scars has expanded and will allow us to maximize scar prevention and to minimize scar morbidity. © 2014 The International Society of Dermatology.

Solving fuel-optimal low-thrust orbital transfers with bang-bang control using a novel continuation technique

NASA Astrophysics Data System (ADS)

Zhu, Zhengfan; Gan, Qingbo; Yang, Xin; Gao, Yang

2017-08-01

We have developed a novel continuation technique to solve optimal bang-bang control for low-thrust orbital transfers considering the first-order necessary optimality conditions derived from Lawden's primer vector theory. Continuation on the thrust amplitude is mainly described in this paper. Firstly, a finite-thrust transfer with an ;On-Off-On; thrusting sequence is modeled using a two-impulse transfer as initial solution, and then the thrust amplitude is decreased gradually to find an optimal solution with minimum thrust. Secondly, the thrust amplitude is continued from its minimum value to positive infinity to find the optimal bang-bang control, and a thrust switching principle is employed to determine the control structure by monitoring the variation of the switching function. In the continuation process, a bifurcation of bang-bang control is revealed and the concept of critical thrust is proposed to illustrate this phenomenon. The same thrust switching principle is also applicable to the continuation on other parameters, such as transfer time, orbital phase angle, etc. By this continuation technique, fuel-optimal orbital transfers with variable mission parameters can be found via an automated algorithm, and there is no need to provide an initial guess for the costate variables. Moreover, continuation is implemented in the solution space of bang-bang control that is either optimal or non-optimal, which shows that a desired solution of bang-bang control is obtained via continuation on a single parameter starting from an existing solution of bang-bang control. Finally, numerical examples are presented to demonstrate the effectiveness of the proposed continuation technique. Specifically, this continuation technique provides an approach to find multiple solutions satisfying the first-order necessary optimality conditions to the same orbital transfer problem, and a continuation strategy is presented as a preliminary approach for solving the bang-bang control of many

Infantile hemangioma: pulsed dye laser versus surgical therapy

NASA Astrophysics Data System (ADS)

Remlova, E.; Dostalova, T.; Michalusova, I.; Vranova, J.; Jelinkova, H.; Hubacek, M.

2014-05-01

Hemangioma is a mesenchymal benign tumor formed by blood vessels. Anomalies affect up to 10% of children and they are more common in females than in males. The aim of our study was to compare the treatment efficacy, namely the curative effect and adverse events, such as loss of pigment and appearance of scarring, between classical surgery techniques and laser techniques. For that reason a group of 223 patients with hemangioma was retrospectively reviewed. For treatment, a pulsed dye laser (PDL) (Rhodamine G, wavelength 595 nm, pulsewidth between 0.45 and 40 ms, spot diameter 7 mm, energy density 9-11 J cm-2) was used and the results were compared with a control group treated with classical surgical therapy under general anesthesia. The curative effects, mainly number of sessions, appearance of scars, loss of pigment, and relapses were evaluated as a marker of successful treatment. From the results it was evident that the therapeutic effects of both systems are similar. The PDL was successful in all cases. The surgery patients had four relapses. Classical surgery is directly connected with the presence of scars, but the system is safe for larger hemangiomas. It was confirmed that the PDL had the optimal curative effect without scars for small lesions (approximately 10 mm). Surgical treatment under general anesthesia is better for large hemangiomas; the disadvantage is the presence of scars.

“In vitro” Implantation Technique Based on 3D Printed Prosthetic Prototypes

NASA Astrophysics Data System (ADS)

Tarnita, D.; Boborelu, C.; Geonea, I.; Malciu, R.; Grigorie, L.; Tarnita, D. N.

2018-06-01

In this paper, Rapid Prototyping ZCorp 310 system, based on high-performance composite powder and on resin-high strength infiltration system and three-dimensional printing as a manufacturing method are used to obtain physical prototypes of orthopaedic implants and prototypes of complex functional prosthetic systems directly from the 3D CAD data. These prototypes are useful for in vitro experimental tests and measurements to optimize and obtain final physical prototypes. Using a new elbow prosthesis model prototype obtained by 3D printing, the surgical technique of implantation is established. Surgical implantation was performed on male corpse elbow joint.

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.

A singular value decomposition linear programming (SVDLP) optimization technique for circular cone based robotic radiotherapy.

PubMed

Liang, Bin; Li, Yongbao; Wei, Ran; Guo, Bin; Xu, Xuang; Liu, Bo; Li, Jiafeng; Wu, Qiuwen; Zhou, Fugen

2018-01-05

With robot-controlled linac positioning, robotic radiotherapy systems such as CyberKnife significantly increase freedom of radiation beam placement, but also impose more challenges on treatment plan optimization. The resampling mechanism in the vendor-supplied treatment planning system (MultiPlan) cannot fully explore the increased beam direction search space. Besides, a sparse treatment plan (using fewer beams) is desired to improve treatment efficiency. This study proposes a singular value decomposition linear programming (SVDLP) optimization technique for circular collimator based robotic radiotherapy. The SVDLP approach initializes the input beams by simulating the process of covering the entire target volume with equivalent beam tapers. The requirements on dosimetry distribution are modeled as hard and soft constraints, and the sparsity of the treatment plan is achieved by compressive sensing. The proposed linear programming (LP) model optimizes beam weights by minimizing the deviation of soft constraints subject to hard constraints, with a constraint on the l 1 norm of the beam weight. A singular value decomposition (SVD) based acceleration technique was developed for the LP model. Based on the degeneracy of the influence matrix, the model is first compressed into lower dimension for optimization, and then back-projected to reconstruct the beam weight. After beam weight optimization, the number of beams is reduced by removing the beams with low weight, and optimizing the weights of the remaining beams using the same model. This beam reduction technique is further validated by a mixed integer programming (MIP) model. The SVDLP approach was tested on a lung case. The results demonstrate that the SVD acceleration technique speeds up the optimization by a factor of 4.8. Furthermore, the beam reduction achieves a similar plan quality to the globally optimal plan obtained by the MIP model, but is one to two orders of magnitude faster. Furthermore, the SVDLP

A singular value decomposition linear programming (SVDLP) optimization technique for circular cone based robotic radiotherapy

NASA Astrophysics Data System (ADS)

Liang, Bin; Li, Yongbao; Wei, Ran; Guo, Bin; Xu, Xuang; Liu, Bo; Li, Jiafeng; Wu, Qiuwen; Zhou, Fugen

2018-01-01

With robot-controlled linac positioning, robotic radiotherapy systems such as CyberKnife significantly increase freedom of radiation beam placement, but also impose more challenges on treatment plan optimization. The resampling mechanism in the vendor-supplied treatment planning system (MultiPlan) cannot fully explore the increased beam direction search space. Besides, a sparse treatment plan (using fewer beams) is desired to improve treatment efficiency. This study proposes a singular value decomposition linear programming (SVDLP) optimization technique for circular collimator based robotic radiotherapy. The SVDLP approach initializes the input beams by simulating the process of covering the entire target volume with equivalent beam tapers. The requirements on dosimetry distribution are modeled as hard and soft constraints, and the sparsity of the treatment plan is achieved by compressive sensing. The proposed linear programming (LP) model optimizes beam weights by minimizing the deviation of soft constraints subject to hard constraints, with a constraint on the l 1 norm of the beam weight. A singular value decomposition (SVD) based acceleration technique was developed for the LP model. Based on the degeneracy of the influence matrix, the model is first compressed into lower dimension for optimization, and then back-projected to reconstruct the beam weight. After beam weight optimization, the number of beams is reduced by removing the beams with low weight, and optimizing the weights of the remaining beams using the same model. This beam reduction technique is further validated by a mixed integer programming (MIP) model. The SVDLP approach was tested on a lung case. The results demonstrate that the SVD acceleration technique speeds up the optimization by a factor of 4.8. Furthermore, the beam reduction achieves a similar plan quality to the globally optimal plan obtained by the MIP model, but is one to two orders of magnitude faster. Furthermore, the SVDLP

Surgical closure of the larynx for the treatment of intractable aspiration: surgical technique and clinical results.

PubMed

Takano, Shingo; Goto, Takao; Kabeya, Masayuki; Tayama, Niro

2012-06-01

Surgical closure of the larynx (SCL) is a method to prevent aspiration that sacrifices vocal function. The aim of this report was to introduce our new surgical method and perform clinical analysis of these cases. Retrospective review. We performed 32 cases of surgical closure using our original method in two institutions from 2003 to 2011. We analyzed leakage and other complications and pre- and postoperative routes of nutrition. The main feature of our method is reduction of the entire structure of the larynx. To reduce the laryngeal space, we excised both edges of the cut thyroid cartilage. Sutures were made collectively in upper flaps (false folds) and lower flaps (vocal folds), with no need for insertion of a hinged muscle flap. No clinical leakage was encountered in any cases, and aspiration pneumonia was completely prevented postoperatively. Most patients (56%) became able to ingest orally alone or in combination with tube feeding. Prevention of aspiration pneumonia is very important in medical management, and we believe that our method offers a good means by which to achieve this goal. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

The role of simulation in surgical training.

PubMed Central

Torkington, J.; Smith, S. G.; Rees, B. I.; Darzi, A.

2000-01-01

Surgical training has undergone many changes in the last decade. One outcome of these changes is the interest that has been generated in the possibility of training surgical skills outside the operating theatre. Simulation of surgical procedures and human tissue, if perfect, would allow complete transfer of techniques learnt in a skills laboratory directly to the operating theatre. Several techniques of simulation are available including artificial tissues, animal models and virtual reality computer simulation. Each is discussed in this article and their advantages and disadvantages considered. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:10743423

The trans-frontal-sinus subcranial approach for removal of large olfactory groove meningiomas: surgical technique and comparison to other approaches.

PubMed

Boari, Nicola; Gagliardi, Filippo; Roberti, Fabio; Barzaghi, Lina Raffaella; Caputy, Anthony J; Mortini, Pietro

2013-05-01

Several surgical approaches have been previously reported for the treatment of olfactory groove meningiomas (OGM).The trans-frontal-sinus subcranial approach (TFSSA) for the removal of large OGMs is described, comparing it with other reported approaches in terms of advantages and drawbacks. The TFSSA was performed on cadaveric specimens to illustrate the surgical technique. The surgical steps of the TFSSA and the related anatomical pictures are reported. The approach was adopted in a clinical setting; a case illustration is reported to demonstrate the feasibility of the described approach and to provide intraoperative pictures. The TFSSA represents a possible route to treat large OGMs. The subcranial approach provides early devascularization of the tumor, direct tumor access from the base without traction on the frontal lobes, good overview of dissection of the optic nerves and anterior cerebral arteries, and dural reconstruction with pedicled pericranial flap. Georg Thieme Verlag KG Stuttgart · New York.

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.

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

PubMed Central

Buntrock, Stefan

2012-01-01

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

Optimization techniques using MODFLOW-GWM

USGS Publications Warehouse

Grava, Anna; Feinstein, Daniel T.; Barlow, Paul M.; Bonomi, Tullia; Buarne, Fabiola; Dunning, Charles; Hunt, Randall J.

2015-01-01

An important application of optimization codes such as MODFLOW-GWM is to maximize water supply from unconfined aquifers subject to constraints involving surface-water depletion and drawdown. In optimizing pumping for a fish hatchery in a bedrock aquifer system overlain by glacial deposits in eastern Wisconsin, various features of the GWM-2000 code were used to overcome difficulties associated with: 1) Non-linear response matrices caused by unconfined conditions and head-dependent boundaries; 2) Efficient selection of candidate well and drawdown constraint locations; and 3) Optimizing against water-level constraints inside pumping wells. Features of GWM-2000 were harnessed to test the effects of systematically varying the decision variables and constraints on the optimized solution for managing withdrawals. An important lesson of the procedure, similar to lessons learned in model calibration, is that the optimized outcome is non-unique, and depends on a range of choices open to the user. The modeler must balance the complexity of the numerical flow model used to represent the groundwater-flow system against the range of options (decision variables, objective functions, constraints) available for optimizing the model.

Innovating for quality and value: Utilizing national quality improvement programs to identify opportunities for responsible surgical innovation.

PubMed

Woo, Russell K; Skarsgard, Erik D

2015-06-01

Innovation in surgical techniques, technology, and care processes are essential for improving the care and outcomes of surgical patients, including children. The time and cost associated with surgical innovation can be significant, and unless it leads to improvements in outcome at equivalent or lower costs, it adds little or no value from the perspective of the patients, and decreases the overall resources available to our already financially constrained healthcare system. The emergence of a safety and quality mandate in surgery, and the development of the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) allow needs-based surgical care innovation which leads to value-based improvement in care. In addition to general and procedure-specific clinical outcomes, surgeons should consider the measurement of quality from the patients' perspective. To this end, the integration of validated Patient Reported Outcome Measures (PROMs) into actionable, benchmarked institutional outcomes reporting has the potential to facilitate quality improvement in process, treatment and technology that optimizes value for our patients and health system. Copyright © 2015 Elsevier Inc. All rights reserved.

Surgical therapy in chronic pancreatitis.

PubMed

Neal, C P; Dennison, A R; Garcea, G

2012-12-01

Chronic pancreatitis (CP) is an inflammatory disease of the pancreas which causes chronic pain, as well as exocrine and endocrine failure in the majority of patients, together producing social and domestic upheaval and a very poor quality of life. At least half of patients will require surgical intervention at some stage in their disease, primarily for the treatment of persistent pain. Available data have now confirmed that surgical intervention may produce superior results to conservative and endoscopic treatment. Comprehensive individual patient assessment is crucial to optimal surgical management, however, in order to determine which morphological disease variant (large duct disease, distal stricture with focal disease, expanded head or small duct/minimal change disease) is present in the individual patient, as a wide and differing range of surgical approaches are possible depending upon the specific abnormality within the gland. This review comprehensively assesses the evidence for these differing approaches to surgical intervention in chronic pancreatitis. Surgical drainage procedures should be limited to a small number of patients with a dilated duct and no pancreatic head mass. Similarly, a small population presenting with a focal stricture and tail only disease may be successfully treated by distal pancreatectomy. Long-term results of both of these procedure types are poor, however. More impressive results have been yielded for the surgical treatment of the expanded head, for which a range of surgical options now exist. Evidence from level I studies and a recent meta-analysis suggests that duodenum-preserving resections offer benefits compared to pancreaticoduodenectomy, though the results of the ongoing, multicentre ChroPac trial are awaited to confirm this. Further data are also needed to determine which of the duodenum-preserving procedures provides optimal results. In relation to small duct/minimal change disease total pancreatectomy represents the only

Planum Sphenoidale and Tuberculum Sellae Meningiomas: Operative Nuances of a Modern Surgical Technique with Outcome and Proposal of a New Classification System.

PubMed

Mortazavi, Martin M; Brito da Silva, Harley; Ferreira, Manuel; Barber, Jason K; Pridgeon, James S; Sekhar, Laligam N

2016-02-01

The resection of planum sphenoidale and tuberculum sellae meningiomas is challenging. A universally accepted classification system predicting surgical risk and outcome is still lacking. We report a modern surgical technique specific for planum sphenoidale and tuberculum sellae meningiomas with associated outcome. A new classification system that can guide the surgical approach and may predict surgical risk is proposed. We conducted a retrospective review of the patients who between 2005 and March 2015 underwent a craniotomy or endoscopic surgery for the resection of meningiomas involving the suprasellar region. Operative nuances of a modified frontotemporal craniotomy and orbital osteotomy technique for meningioma removal and reconstruction are described. Twenty-seven patients were found to have tumors arising mainly from the planum sphenoidale or the tuberculum sellae; 25 underwent frontotemporal craniotomy and tumor removal with orbital osteotomy and bilateral optic canal decompression, and 2 patients underwent endonasal transphenoidal resection. The most common presenting symptom was visual disturbance (77%). Vision improved in 90% of those who presented with visual decline, and there was no permanent visual deterioration. Cerebrospinal fluid leak occurred in one of the 25 cranial cases (4%) and in 1 of 2 transphenoidal cases (50%), and in both cases it resolved with treatment. There was no surgical mortality. An orbitotomy and early decompression of the involved optic canal are important for achieving gross total resection, maximizing visual improvement, and avoiding recurrence. The visual outcomes were excellent. A new classification system that can allow the comparison of different series and approaches and indicate cases that are more suitable for an endoscopic transsphenoidal approach is presented. Copyright © 2016 Elsevier Inc. All rights reserved.

Half a billion surgical cases: Aligning surgical delivery with best-performing health systems.

PubMed

Shrime, Mark G; Daniels, Kimberly M; Meara, John G

2015-07-01

Surgical delivery varies 200-fold across countries. No direct correlation exists, however, between surgical delivery and health outcomes, making it difficult to pinpoint a goal for surgical scale-up. This report determines the amount of surgery that would be delivered worldwide if the world aligned itself with countries providing the best health outcomes. Annual rates of surgical delivery have been published previously for 129 countries. Five health outcomes were plotted against reported surgical delivery. Univariate and multivariate polynomial regression curves were fit, and the optimal point on each regression curve was determined by solving for first-order conditions. The country closest to the optimum for each health outcome was taken as representative of the best-performing health system. Monetary inputs to and surgical procedures provided by these systems were scaled to the global population. For 3 of the 5 health outcomes, optima could be found. Globally, 315 million procedures currently are provided annually. If global delivery mirrored the 3 best-performing countries, between 360 million and 460 million cases would be provided annually. With population growth, this will increase to approximately half a billion cases by 2030. Health systems delivering these outcomes spend approximately 10% of their GDP on health. This is the first study to provide empirical evidence for the surgical output that an ideal health system would provide. Our results project ideal delivery worldwide of approximately 550 million annual surgical cases by 2030. Copyright © 2015 Elsevier Inc. All rights reserved.

Half a billion surgical cases: Aligning surgical delivery with best-performing health systems

PubMed Central

Shrime, Mark G.; Daniels, Kimberly M.; Meara, John G.

2015-01-01

Background Surgical delivery varies 200-fold across countries. No direct correlation exists, however, between surgical delivery and health outcomes, making it difficult to pinpoint a goal for surgical scale-up. This report determines the amount of surgery that would be delivered worldwide if the world aligned itself with countries providing the best health outcomes. Methods Annual rates of surgical delivery have been published previously for 129 countries. Five health outcomes were plotted against reported surgical delivery. Univariate and multivariate polynomial regression curves were fit, and the optimal point on each regression curve was determined by solving for first-order conditions. The country closest to the optimum for each health outcome was taken as representative of the best-performing health system. Monetary inputs to and surgical procedures provided by these systems were scaled to the global population. Results For 3 of the 5 health outcomes, optima could be found. Globally, 315 million procedures currently are provided annually. If global delivery mirrored the 3 best-performing countries, between 360 million and 460 million cases would be provided annually. With population growth, this will increase to approximately half a billion cases by 2030. Health systems delivering these outcomes spend approximately 10% of their GDP on health. Conclusion This is the first study to provide empirical evidence for the surgical output that an ideal health system would provide. Our results project ideal delivery worldwide of approximately 550 million annual surgical cases by 2030. PMID:25934078

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

PubMed

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

2018-05-01

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

Practical Framework for an Electron Beam Induced Current Technique Based on a Numerical Optimization Approach

NASA Astrophysics Data System (ADS)

Yamaguchi, Hideshi; Soeda, Takeshi

2015-03-01

A practical framework for an electron beam induced current (EBIC) technique has been established for conductive materials based on a numerical optimization approach. Although the conventional EBIC technique is useful for evaluating the distributions of dopants or crystal defects in semiconductor transistors, issues related to the reproducibility and quantitative capability of measurements using this technique persist. For instance, it is difficult to acquire high-quality EBIC images throughout continuous tests due to variation in operator skill or test environment. Recently, due to the evaluation of EBIC equipment performance and the numerical optimization of equipment items, the constant acquisition of high contrast images has become possible, improving the reproducibility as well as yield regardless of operator skill or test environment. The technique proposed herein is even more sensitive and quantitative than scanning probe microscopy, an imaging technique that can possibly damage the sample. The new technique is expected to benefit the electrical evaluation of fragile or soft materials along with LSI materials.

Surgical treatment of gynecomastia: complications and outcomes.

PubMed

Li, Chun-Chang; Fu, Ju-Peng; Chang, Shun-Cheng; Chen, Tim-Mo; Chen, Shyi-Gen

2012-11-01

Gynecomastia is defined as the benign enlargement of the male breast. Multiple surgical options have been used to improve outcomes. The aim of this study was to analyze the surgical approaches to the treatment of gynecomastia and their outcomes over a 10-year period. All patients undergoing surgical correction of gynecomastia in our department between 2000 and 2010 were included for retrospective evaluation. The data were analyzed for etiology, stage of gynecomastia, surgical technique, complications, risk factors, and revision rate. The surgical result was evaluated with self-assessment questionnaires. A total of 41 patients with 75 operations were included. Techniques included subcutaneous mastectomy alone or with additional ultrasound-assisted liposuction (UAL) and isolated UAL. The surgical revision rate for all patients was 4.8%. The skin-sparing procedure gave good surgical results in grade IIb and grade III gynecomastia with low revision and complication rates. The self-assessment report revealed a good level of overall satisfaction and improvement in self-confidence (average scores 9.4 and 9.2, respectively, on a 10-point scale). The treatment of gynecomastia requires an individualized approach. Subcutaneous mastectomy combined with UAL could be used as the first choice for surgical treatment of grade II and III gynecomastia.

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.

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.

Cache Energy Optimization Techniques For Modern Processors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mittal, Sparsh

2013-01-01

newcomers 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.« less

A fuzzy optimal threshold technique for medical images

NASA Astrophysics Data System (ADS)

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

2012-01-01

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

Determining a core curriculum in surgical infections for fellowship training in acute care surgery using the Delphi technique.

PubMed

May, Addison K; Cuschieri, Joseph; Johnson, Jeffrey L; Duane, Therese M; Cherry-Bukowiec, Jill R; Rosengart, Matthew R

2013-12-01

Recent data highlight the educational, financial, and healthcare benefits of acute care surgery (ACS). These data serve as the impetus to create ACS fellowships, which now are accredited by the American Association for the Surgery of Trauma. However, the core components of a curriculum fundamental for ACS training and that yield competence and proficiency have yet to be determined. Experts in ACS from the United States (n=86) were asked to propose topics in surgical infectious diseases of potential importance in developing a core curriculum for ACS fellowship training. They were then required to rank these topics in order of importance to identify those considered most fundamental. Thirty-one filters ranking in the highest tertile are proposed as topics of surgical infectious diseases that are fundamental to any curriculum of ACS fellowship training. The majority pertains to aspects of thoracic infections (n=8), although topics of soft tissue infections (n=5) comprised four of the top 10 (40%) filters. Abdominal infections (n=6), the biology of sepsis (n=6), and risk, prevention, and prophylaxis (n=6) completed the list. This study identifies the most important topics of surgical infectious disease that merit consideration for incorporation into a core curriculum of ACS training. Hopefully, this information will assist in the development of ACS fellowships that optimize the training of future ACS surgeons.

New multimedia advances in surgical information.

PubMed

Glenn, Ian C; Abdulhai, Sophia; Lamoshi, Abdulraouf; Ponsky, Todd A

2018-06-01

When discussing new trends in pediatric surgery, the tendency is to focus on novel surgical technology and techniques. However, it is equally important to examine how the practicing surgeon stays abreast in an ever-changing field. This article serves as a brief guide to the future of surgical education for the attending surgeon. Broadly, advances in surgical education consist of new methods of filtration and delivery of knowledge.

Providing care for critically ill surgical patients: challenges and recommendations.

PubMed

Tisherman, Samuel A; Kaplan, Lewis; Gracias, Vicente H; Beilman, Gregory J; Toevs, Christine; Byrnes, Matthew C; Coopersmith, Craig M

2013-07-01

Providing optimal care for critically ill and injured surgical patients will become more challenging with staff shortages for surgeons and intensivists. This white paper addresses the historical issues behind the present situation, the need for all intensivists to engage in dedicated critical care per the intensivist model, and the recognition that intensivists from all specialties can provide optimal care for the critically ill surgical patient, particularly with continuing involvement by the surgeon of record. The new acute care surgery training paradigm (including trauma, surgical critical care, and emergency general surgery) has been developed to increase interest in trauma and surgical critical care, but the number of interested trainees remains too few. Recommendations are made for broadening the multidisciplinary training and practice opportunities in surgical critical care for intensivists from all base specialties and for maintaining the intensivist model within acute care surgery practice. Support from academic and administrative leadership, as well as national organizations, will be needed.

Surgical data science: The new knowledge domain

PubMed Central

Vedula, S. Swaroop; Hager, Gregory D.

2017-01-01

Healthcare in general, and surgery/interventional care in particular, is evolving through rapid advances in technology and increasing complexity of care with the goal of maximizing quality and value of care. While innovations in diagnostic and therapeutic technologies have driven past improvements in quality of surgical care, future transformation in care will be enabled by data. Conventional methodologies, such as registry studies, are limited in their scope for discovery and research, extent and complexity of data, breadth of analytic techniques, and translation or integration of research findings into patient care. We foresee the emergence of Surgical/Interventional Data Science (SDS) as a key element to addressing these limitations and creating a sustainable path toward evidence-based improvement of interventional healthcare pathways. SDS will create tools to measure, model and quantify the pathways or processes within the context of patient health states or outcomes, and use information gained to inform healthcare decisions, guidelines, best practices, policy, and training, thereby improving the safety and quality of healthcare and its value. Data is pervasive throughout the surgical care pathway; thus, SDS can impact various aspects of care including prevention, diagnosis, intervention, or post-operative recovery. Existing literature already provides preliminary results suggesting how a data science approach to surgical decision-making could more accurately predict severe complications using complex data from pre-, intra-, and post-operative contexts, how it could support intra-operative decision-making using both existing knowledge and continuous data streams throughout the surgical care pathway, and how it could enable effective collaboration between human care providers and intelligent technologies. In addition, SDS is poised to play a central role in surgical education, for example, through objective assessments, automated virtual coaching, and robot

Surgical data science: The new knowledge domain.

PubMed

Vedula, S Swaroop; Hager, Gregory D

2017-04-01

Healthcare in general, and surgery/interventional care in particular, is evolving through rapid advances in technology and increasing complexity of care with the goal of maximizing quality and value of care. While innovations in diagnostic and therapeutic technologies have driven past improvements in quality of surgical care, future transformation in care will be enabled by data. Conventional methodologies, such as registry studies, are limited in their scope for discovery and research, extent and complexity of data, breadth of analytic techniques, and translation or integration of research findings into patient care. We foresee the emergence of Surgical/Interventional Data Science (SDS) as a key element to addressing these limitations and creating a sustainable path toward evidence-based improvement of interventional healthcare pathways. SDS will create tools to measure, model and quantify the pathways or processes within the context of patient health states or outcomes, and use information gained to inform healthcare decisions, guidelines, best practices, policy, and training, thereby improving the safety and quality of healthcare and its value. Data is pervasive throughout the surgical care pathway; thus, SDS can impact various aspects of care including prevention, diagnosis, intervention, or post-operative recovery. Existing literature already provides preliminary results suggesting how a data science approach to surgical decision-making could more accurately predict severe complications using complex data from pre-, intra-, and post-operative contexts, how it could support intra-operative decision-making using both existing knowledge and continuous data streams throughout the surgical care pathway, and how it could enable effective collaboration between human care providers and intelligent technologies. In addition, SDS is poised to play a central role in surgical education, for example, through objective assessments, automated virtual coaching, and robot

How can surgical training benefit from theories of skilled motor development, musical skill acquisition and performance psychology?

PubMed

McCaskie, Andrew W; Kenny, Dianna T; Deshmukh, Sandeep

2011-05-02

Trainee surgeons must acquire expert status in the context of reduced hours, reduced operating room time and the need to learn complex skills involving screen-mediated techniques, computers and robotics. Ever more sophisticated surgical simulation strategies have been helpful in providing surgeons with the opportunity to practise, but not all of these strategies are widely available. Similarities in the motor skills required in skilled musical performance and surgery suggest that models of music learning, and particularly skilled motor development, may be applicable in training surgeons. More attention should be paid to factors associated with optimal arousal and optimal performance in surgical training - lessons learned from helping anxious musicians optimise performance and manage anxiety may also be transferable to trainee surgeons. The ways in which the trainee surgeon moves from novice to expert need to be better understood so that this process can be expedited using current knowledge in other disciplines requiring the performance of complex fine motor tasks with high cognitive load under pressure.

Surgical treatment for apparent early stage endometrial cancer

PubMed Central

2014-01-01

Most experts would agree that the standard surgical treatment for endometrial cancer includes a hysterectomy and bilateral salpingo-oophorectomy; however, the benefit of full surgical staging with lymph node dissection in patients with apparent early stage disease remains a topic of debate. Recent prospective data and advances in laparoscopic techniques have transformed this disease into one that can be successfully managed with minimally invasive surgery. This review will discuss the current surgical management of apparent early stage endometrial cancer and some of the new techniques that are being incorporated. PMID:24596812

Abdominal tumours in children: 3-D visualisation and surgical planning.

PubMed

Günther, P; Schenk, J P; Wunsch, R; Tröger, J; Waag, K L

2004-10-01

Solid abdominal tumours are of special importance in the field of paediatric surgery. Because of the dangers of cumulative irradiation and improved delineation of soft parts MRI is usually employed in children for diagnostic assessment. Compiling the radiologic information for surgical planning is often difficult by conventional methods. Newly improved and efficient 3-D volume rendering software is now available for visual reconstruction of tumour anatomy utilising segmentation and other special techniques. Because the intraoperative complication rate is close to 20 % as described in the literature, optimal preoperative visualisation and planning would seem imperative. All children with solid abdominal tumours at Heidelberg University in the year 2002 were included in this study. MR examinations were performed with a 0.5 Tesla magnet using a standard protocol. All MR data were processed with VG Studio Max 1.1, converting the two-dimensional data into three-dimensional data. This report presents 15 cases using this special technique: 7 with abdominal neuroblastoma, 6 with nephroblastoma, 1 ganglioneuroma, and 1 ovarian teratoma. Our experience shows that a better understanding of the surgical anatomy, particularly regarding the surrounding organs and vasculature, can be helpful in decreasing the incidence of inadvertent intraoperative injuries to these structures.

Optimization of Native and Formaldehyde iPOND Techniques for Use in Suspension Cells.

PubMed

Wiest, Nathaniel E; Tomkinson, Alan E

2017-01-01

The isolation of proteins on nascent DNA (iPOND) technique developed by the Cortez laboratory allows a previously unparalleled ability to examine proteins associated with replicating and newly synthesized DNA in mammalian cells. Both the original, formaldehyde-based iPOND technique and a more recent derivative, accelerated native iPOND (aniPOND), have mostly been performed in adherent cell lines. Here, we describe modifications to both protocols for use with suspension cell lines. These include cell culture, pulse, and chase conditions that optimize sample recovery in both protocols using suspension cells and several key improvements to the published aniPOND technique that reduce sample loss, increase signal to noise, and maximize sample recovery. Additionally, we directly and quantitatively compare the iPOND and aniPOND protocols to test the strengths and limitations of both. Finally, we present a detailed protocol to perform the optimized aniPOND protocol in suspension cell lines. © 2017 Elsevier Inc. All rights reserved.

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

PubMed

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

2007-01-01

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

Surgical treatment for ectopic atrial tachycardia.

PubMed

Graffigna, A; Vigano, M; Pagani, F; Salerno, G

1992-08-01

Atrial tachycardia is an infrequent but potentially dangerous arrhythmia which often determines cardiac enlargement. Surgical ablation of the arrhythmia is effective and safe, provided a careful atrial mapping is performed and the surgical technique is tailored to the individual focus location. Eight patients underwent surgical ablation of ectopic atrial tachycardia between 1977 and 1990. Different techniques were adopted for each patient according to the anatomical location of the focus and possibly associated arrhythmias. Whenever possible, a closed heart procedure was chosen. In 1 patient a double focal origin was found and treated by separate procedures. In 1 patient with ostium secundum atrial septal defect and atrial flutter, surgical isolation of the right appendage and the ectopic focus was performed. In all patients ectopic atrial tachycardia was ablated with maintenance of the sinoatrial and atrioventricular nodal function as well as internodal conduction. In follow-up up to December 1991, no recurrency was recorded.

Diffusion of surgical techniques in early stage breast cancer: variables related to adoption and implementation of sentinel lymph node biopsy.

PubMed

Vanderveen, Kimberly A; Paterniti, Debora A; Kravitz, Richard L; Bold, Richard J

2007-05-01

Understanding how physicians acquire and adopt new technologies for cancer diagnosis and treatment is poorly understood, yet is critical to the dissemination of evidence-based practices. Sentinel lymph node biopsy (SLNB) has recently become a standard technique for axillary staging in early breast cancer and is an ideal platform for studying medical technology diffusion. We sought to describe the timing of SLNB adoption and patterns of surgeon interactions with the following educational sources: local university training program, surgical literature, national meetings/courses, national specialty centers, and other local surgeons. A cross-sectional survey that used semistructured interviews was used to assess timing of adoption, practice patterns, and learning sources for SLNB among surgical oncologists and general surgeons in a single metropolitan area. A total of 44 eligible surgeons were identified; 38 (86%) participated. All surgical oncologists (11 of 11) and most general surgeons (26 of 27) had implemented SLNB. Surgical oncologists were older (mean 51 vs. 48 years, P = .02) and had used SLNB longer (6.1 vs. 3.3 years, P = .01) than general surgeons. By use of social network diagrams, surgical oncologists and the university training program were shown to be key intermediaries between general surgeons and national specialty centers. Surgeons in group practice tended to use more learning sources than solo practitioners. Surgical oncologists and university-based surgeons play key educational roles in disseminating new cancer treatments and therefore have a professional responsibility to educate other community physicians to increase the use of the most current, evidence-based practices.

Ethics and surgical innovation: challenges to the professionalism of surgeons.

PubMed

Angelos, Peter

2013-01-01

The future of surgical progress depends on surgeons finding innovative solutions to their patients' problems. Surgical innovation is critical to advances in surgery. However, surgical innovation also raises a series of ethical issues that challenge the professionalism of surgeons. The very criteria for defining surgical progress have changed as patients may value more than simply reductions in morbidity and mortality. The requirement for informed consent prior to surgery is difficult when an innovative surgical procedure is planned since the risks of the novel operation may not be known. In addition, even if the risks are known in the hands of the innovator, the actual risks to patients when surgeons are learning the new technique are unknown. New techniques often depend on new technology which may be significantly more expensive than traditional techniques. There are no clear criteria to decide which new innovative techniques are going to turn out to be truly beneficial to patients. Many surgical innovations depend on new products which may have been developed as collaborative efforts between surgical device companies and surgeons. Although many currently accepted therapies were developed in this fashion, the collaboration of surgeons and device companies raises the potential for significant harmful conflicts of interest. In the decades to come, careful attention to these and other ethical issues will help to define the future professional standing of surgeons. Copyright © 2013 Elsevier Ltd and Surgical Associates Ltd. All rights reserved.

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.

Endoscopic septoplasty in primary cases using electromechanical instruments: surgical technique, efficacy and results.

PubMed

De Sousa Fontes, Aderito; Sandrea Jiménez, Minaret; Chacaltana Ayerve, Rosa R

2013-01-01

The microdebrider is a surgical tool which has been used successfully in many endoscopic surgical procedures in otolaryngology. In this study, we analysed our experience using this powered instrument in the resection of obstructive nasal septum deviations. This was a longitudinal, prospective, descriptive study conducted between January and June 2007 on 141 patients who consulted for chronic nasal obstruction caused by a septal deviation or deformity and underwent powered endoscopic septoplasty (PES). The mean age was 39.9 years (15-63 years); 60.28% were male (n=85) The change in nasal symptom severity decreased after surgery from 6.12 (preoperative) to 2.01 (postoperative). Patients undergoing PES had a significant reduction of nasal symptoms in the pre- and postoperative period, which was statistically significant (P<.05). There were no statistically significant differences between the results at the 2 nd week, 6th week and 5th year after surgery. The 100% of patients were satisfied with the results of surgery and no patient answered "No" to the question added to compare patient satisfaction after surgery. Minor complications in the postoperative period were present in 4.96% of the cases. Powered endoscopic septoplasty allows accurate, conservative repair of obstructive nasal septum deviations, with fewer complications and better functional results. In our experience, this technique offered significant perioperative advantages with high postoperative patient satisfaction in terms of reducing the severity of nasal symptoms. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Optimization of chiral structures for microscale propulsion.

PubMed

Keaveny, Eric E; Walker, Shawn W; Shelley, Michael J

2013-02-13

Recent advances in micro- and nanoscale fabrication techniques allow for the construction of rigid, helically shaped microswimmers that can be actuated using applied magnetic fields. These swimmers represent the first steps toward the development of microrobots for targeted drug delivery and minimally invasive surgical procedures. To assess the performance of these devices and improve on their design, we perform shape optimization computations to determine swimmer geometries that maximize speed in the direction of a given applied magnetic torque. We directly assess aspects of swimmer shapes that have been developed in previous experimental studies, including helical propellers with elongated cross sections and attached payloads. From these optimizations, we identify key improvements to existing designs that result in swimming speeds that are 70-470% of their original values.

Two-Stage Technique Used to Manage Severe Upper Airway Obstruction and Avoid Surgical Tracheostomy: A Case Report.

PubMed

Onwochei, Desire N; El-Boghdadly, Kariem; Ahmad, Imran

2018-03-01

Severe upper airway obstruction is commonly managed with surgical tracheostomy under local anesthesia. We present a 49-year-old woman with postradiotherapy laryngeal fixation and transglottic stenosis for dilation of a pharyngeal stricture who refused elective tracheostomy. A 2-stage technique was used, which involved an awake fiberoptic intubation, followed by the transtracheal insertion of a Cricath needle and ventilation using an ejector-based Ventrain device. We discuss management aspects of this clinical scenario and the principles by which the Ventrain works.

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

PubMed

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

2016-04-12

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

Multilayer perceptron architecture optimization using parallel computing techniques.

PubMed

Castro, Wilson; Oblitas, Jimy; Santa-Cruz, Roberto; Avila-George, Himer

2017-01-01

The objective of this research was to develop a methodology for optimizing multilayer-perceptron-type neural networks by evaluating the effects of three neural architecture parameters, namely, number of hidden layers (HL), neurons per hidden layer (NHL), and activation function type (AF), on the sum of squares error (SSE). The data for the study were obtained from quality parameters (physicochemical and microbiological) of milk samples. Architectures or combinations were organized in groups (G1, G2, and G3) generated upon interspersing one, two, and three layers. Within each group, the networks had three neurons in the input layer, six neurons in the output layer, three to twenty-seven NHL, and three AF (tan-sig, log-sig, and linear) types. The number of architectures was determined using three factorial-type experimental designs, which reached 63, 2 187, and 50 049 combinations for G1, G2 and G3, respectively. Using MATLAB 2015a, a logical sequence was designed and implemented for constructing, training, and evaluating multilayer-perceptron-type neural networks using parallel computing techniques. The results show that HL and NHL have a statistically relevant effect on SSE, and from two hidden layers, AF also has a significant effect; thus, both AF and NHL can be evaluated to determine the optimal combination per group. Moreover, in the three study groups, it is observed that there is an inverse relationship between the number of processors and the total optimization time.

Multilayer perceptron architecture optimization using parallel computing techniques

PubMed Central

Castro, Wilson; Oblitas, Jimy; Santa-Cruz, Roberto; Avila-George, Himer

2017-01-01

The objective of this research was to develop a methodology for optimizing multilayer-perceptron-type neural networks by evaluating the effects of three neural architecture parameters, namely, number of hidden layers (HL), neurons per hidden layer (NHL), and activation function type (AF), on the sum of squares error (SSE). The data for the study were obtained from quality parameters (physicochemical and microbiological) of milk samples. Architectures or combinations were organized in groups (G1, G2, and G3) generated upon interspersing one, two, and three layers. Within each group, the networks had three neurons in the input layer, six neurons in the output layer, three to twenty-seven NHL, and three AF (tan-sig, log-sig, and linear) types. The number of architectures was determined using three factorial-type experimental designs, which reached 63, 2 187, and 50 049 combinations for G1, G2 and G3, respectively. Using MATLAB 2015a, a logical sequence was designed and implemented for constructing, training, and evaluating multilayer-perceptron-type neural networks using parallel computing techniques. The results show that HL and NHL have a statistically relevant effect on SSE, and from two hidden layers, AF also has a significant effect; thus, both AF and NHL can be evaluated to determine the optimal combination per group. Moreover, in the three study groups, it is observed that there is an inverse relationship between the number of processors and the total optimization time. PMID:29236744

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

PubMed

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

2015-06-01

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

Prototyping for surgical and prosthetic treatment.

PubMed

Goiato, Marcelo Coelho; Santos, Murillo Rezende; Pesqueira, Aldiéris Alves; Moreno, Amália; dos Santos, Daniela Micheline; Haddad, Marcela Filié

2011-05-01

Techniques of rapid prototyping were introduced in the 1980s in the field of engineering for the fabrication of a solid model based on a computed file. After its introduction in the biomedical field, several applications were raised for the fabrication of models to ease surgical planning and simulation in implantology, neurosurgery, and orthopedics, as well as for the fabrication of maxillofacial prostheses. Hence, the literature has described the evolution of rapid prototyping technique in health care, which allowed easier technique, improved surgical results, and fabrication of maxillofacial prostheses. Accordingly, a literature review on MEDLINE (PubMed) database was conducted using the keywords rapid prototyping, surgical planning, and maxillofacial prostheses and based on articles published from 1981 to 2010. After reading the titles and abstracts of the articles, 50 studies were selected owing to their correlations with the aim of the current study. Several studies show that the prototypes have been used in different dental-medical areas such as maxillofacial and craniofacial surgery; implantology; neurosurgery; orthopedics; scaffolds of ceramic, polymeric, and metallic materials; and fabrication of personalized maxillofacial prostheses. Therefore, prototyping has been an indispensable tool in several studies and helpful for surgical planning and fabrication of prostheses and implants.

Combinatorial techniques to efficiently investigate and optimize organic thin film processing and properties.

PubMed

Wieberger, Florian; Kolb, Tristan; Neuber, Christian; Ober, Christopher K; Schmidt, Hans-Werner

2013-04-08

In this article we present several developed and improved combinatorial techniques to optimize processing conditions and material properties of organic thin films. The combinatorial approach allows investigations of multi-variable dependencies and is the perfect tool to investigate organic thin films regarding their high performance purposes. In this context we develop and establish the reliable preparation of gradients of material composition, temperature, exposure, and immersion time. Furthermore we demonstrate the smart application of combinations of composition and processing gradients to create combinatorial libraries. First a binary combinatorial library is created by applying two gradients perpendicular to each other. A third gradient is carried out in very small areas and arranged matrix-like over the entire binary combinatorial library resulting in a ternary combinatorial library. Ternary combinatorial libraries allow identifying precise trends for the optimization of multi-variable dependent processes which is demonstrated on the lithographic patterning process. Here we verify conclusively the strong interaction and thus the interdependency of variables in the preparation and properties of complex organic thin film systems. The established gradient preparation techniques are not limited to lithographic patterning. It is possible to utilize and transfer the reported combinatorial techniques to other multi-variable dependent processes and to investigate and optimize thin film layers and devices for optical, electro-optical, and electronic applications.

Accurate pre-surgical determination for self-drilling miniscrew implant placement using surgical guides and cone-beam computed tomography.

PubMed

Miyazawa, Ken; Kawaguchi, Misuzu; Tabuchi, Masako; Goto, Shigemi

2010-12-01

Miniscrew implants have proven to be effective in providing absolute orthodontic anchorage. However, as self-drilling miniscrew implants have become more popular, a problem has emerged, i.e. root contact, which can lead to perforation and other root injuries. To avoid possible root damage, a surgical guide was fabricated and cone-beam computed tomography (CBCT) was used to incorporate guide tubes drilled in accordance with the planned direction of the implants. Eighteen patients (5 males and 13 females; mean age 23.8 years; minimum 10.7, maximum 45.5) were included in the study. Forty-four self-drilling miniscrew implants (diameter 1.6, and length 8 mm) were placed in interradicular bone using a surgical guide procedure, the majority in the maxillary molar area. To determine the success rates, statistical analysis was undertaken using Fisher's exact probability test. CBCT images of post-surgical self-drilling miniscrew implant placement showed no root contact (0/44). However, based on CBCT evaluation, it was necessary to change the location or angle of 52.3 per cent (23/44) of the guide tubes prior to surgery in order to obtain optimal placement. If orthodontic force could be applied to the screw until completion of orthodontic treatment, screw anchorage was recorded as successful. The total success rate of all miniscrews was 90.9 per cent (40/44). Orthodontic self-drilling miniscrew implants must be inserted carefully, particularly in the case of blind placement, since even guide tubes made on casts frequently require repositioning to avoid the roots of the teeth. The use of surgical guides, fabricated using CBCT images, appears to be a promising technique for placement of orthodontic self-drilling miniscrew implants adjacent to the dental roots and maxillary sinuses.

Prototyping a Hybrid Cooperative and Tele-robotic Surgical System for Retinal Microsurgery.

PubMed

Balicki, Marcin; Xia, Tian; Jung, Min Yang; Deguet, Anton; Vagvolgyi, Balazs; Kazanzides, Peter; Taylor, Russell

2011-06-01

This paper presents the design of a tele-robotic microsurgical platform designed for development of cooperative and tele-operative control schemes, sensor based smart instruments, user interfaces and new surgical techniques with eye surgery as the driving application. The system is built using the distributed component-based cisst libraries and the Surgical Assistant Workstation framework. It includes a cooperatively controlled EyeRobot2, a da Vinci Master manipulator, and a remote stereo visualization system. We use constrained optimization based virtual fixture control to provide Virtual Remote-Center-of-Motion (vRCM) and haptic feedback. Such system can be used in a hybrid setup, combining local cooperative control with remote tele-operation, where an experienced surgeon can provide hand-over-hand tutoring to a novice user. In another scheme, the system can provide haptic feedback based on virtual fixtures constructed from real-time force and proximity sensor information.

Prototyping a Hybrid Cooperative and Tele-robotic Surgical System for Retinal Microsurgery

PubMed Central

Balicki, Marcin; Xia, Tian; Jung, Min Yang; Deguet, Anton; Vagvolgyi, Balazs; Kazanzides, Peter; Taylor, Russell

2013-01-01

This paper presents the design of a tele-robotic microsurgical platform designed for development of cooperative and tele-operative control schemes, sensor based smart instruments, user interfaces and new surgical techniques with eye surgery as the driving application. The system is built using the distributed component-based cisst libraries and the Surgical Assistant Workstation framework. It includes a cooperatively controlled EyeRobot2, a da Vinci Master manipulator, and a remote stereo visualization system. We use constrained optimization based virtual fixture control to provide Virtual Remote-Center-of-Motion (vRCM) and haptic feedback. Such system can be used in a hybrid setup, combining local cooperative control with remote tele-operation, where an experienced surgeon can provide hand-over-hand tutoring to a novice user. In another scheme, the system can provide haptic feedback based on virtual fixtures constructed from real-time force and proximity sensor information. PMID:24398557

Surgical perspectives in the management of atrial fibrillation

PubMed Central

Kyprianou, Katerina; Pericleous, Agamemnon; Stavrou, Antonio; Dimitrakaki, Inetzi A; Challoumas, Dimitrios; Dimitrakakis, Georgios

2016-01-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia and a huge public health burden associated with significant morbidity and mortality. For decades an increasing number of patients have undergone surgical treatment of AF, mainly during concomitant cardiac surgery. This has sparked a drive for conducting further studies and researching this field. With the cornerstone Cox-Maze III “cut and sew” procedure being technically challenging, the focus in current literature has turned towards less invasive techniques. The introduction of ablative devices has revolutionised the surgical management of AF, moving away from the traditional surgical lesions. The hybrid procedure, a combination of catheter and surgical ablation is another promising new technique aiming to improve outcomes. Despite the increasing number of studies looking at various aspects of the surgical management of AF, the literature would benefit from more uniformly conducted randomised control trials. PMID:26839656

Solving fractional optimal control problems within a Chebyshev-Legendre operational technique

NASA Astrophysics Data System (ADS)

Bhrawy, A. H.; Ezz-Eldien, S. S.; Doha, E. H.; Abdelkawy, M. A.; Baleanu, D.

2017-06-01

In this manuscript, we report a new operational technique for approximating the numerical solution of fractional optimal control (FOC) problems. The operational matrix of the Caputo fractional derivative of the orthonormal Chebyshev polynomial and the Legendre-Gauss quadrature formula are used, and then the Lagrange multiplier scheme is employed for reducing such problems into those consisting of systems of easily solvable algebraic equations. We compare the approximate solutions achieved using our approach with the exact solutions and with those presented in other techniques and we show the accuracy and applicability of the new numerical approach, through two numerical examples.

Interest rate next-day variation prediction based on hybrid feedforward neural network, particle swarm optimization, and multiresolution techniques

NASA Astrophysics Data System (ADS)

Lahmiri, Salim

2016-02-01

Multiresolution analysis techniques including continuous wavelet transform, empirical mode decomposition, and variational mode decomposition are tested in the context of interest rate next-day variation prediction. In particular, multiresolution analysis techniques are used to decompose interest rate actual variation and feedforward neural network for training and prediction. Particle swarm optimization technique is adopted to optimize its initial weights. For comparison purpose, autoregressive moving average model, random walk process and the naive model are used as main reference models. In order to show the feasibility of the presented hybrid models that combine multiresolution analysis techniques and feedforward neural network optimized by particle swarm optimization, we used a set of six illustrative interest rates; including Moody's seasoned Aaa corporate bond yield, Moody's seasoned Baa corporate bond yield, 3-Month, 6-Month and 1-Year treasury bills, and effective federal fund rate. The forecasting results show that all multiresolution-based prediction systems outperform the conventional reference models on the criteria of mean absolute error, mean absolute deviation, and root mean-squared error. Therefore, it is advantageous to adopt hybrid multiresolution techniques and soft computing models to forecast interest rate daily variations as they provide good forecasting performance.

Surgical treatment of gynecomastia: mastectomy compared to liposuction technique.

PubMed

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

2014-09-01

Gynecomastia is a benign enlargement of the male breast. Yet enlarged breasts cause anxiety, embarrassment, psychosocial discomfort, and fear of breast cancer. The aim of this study was to assess the experience of gynecomastia patients undergoing mastectomy and liposuction surgery. Seven hundred thirty-three patients were analyzed for age, chief complaint, position, grade, operation approach, biopsy, and complication between mastectomy group and liposuction group, from 1990 to 2010. Four hundred two patients (436 breasts) were treated with mastectomy and 331 patients (386 breasts) were treated with liposuction techniques. Three hundred thirty (82%) patients complained of breast lump and lump with pain in mastectomy group, and 204 (61%) patients complained of enlargement breast and enlargement with pain in liposuction group (P < 0.05). All excision specimens were performed for routine histological analysis which showed pathologic diagnosis in patients with mastectomy (100%). One hundred fifty-nine (41%) patients with liposuction acquired pathologic diagnosis through fine needle aspiration and/or core biopsy (P < 0.05). The reoperation rates in mastectomy group and liposuction group were 1.4% and 0.5%, respectively. There were no nipple/areola necrosis and scars in liposuction group. The surgical treatment of gynecomastia required an individual approach, depending on symptoms (lump or enlargement) and requirements of patients. Patients who chose mastectomy were looking for reassurance that their pathologic diagnosis was benign. The increase in the number of liposuction patients was reflected in our study because it was associated with superior esthetic results and few complications.

Surgical management of herpetic keratitis.

PubMed

Tuli, Sonal; Gray, Matthew; Shah, Ankit

2018-07-01

The purpose of this review is to discuss the options for, and recent developments in, the surgical treatment of herpes keratitis. Although the mainstay of treatment of herpetic keratitis is topical or oral antiviral agents, surgical intervention may be necessary for corneal melting or long-term complications such as scarring, lipid keratopathy, necrotizing keratitis, and neurotrophic keratitis. There are a number of surgical therapies available for herpes keratitis. Preferred therapeutic modalities differ based on the size, causation, and location of the infection but consist of either replacement of the infected tissue or structural support of the tissue to allow healing. Incremental improvements in the existing treatment modalities have made them more effective, easier, and safer, whereas novel therapies such as corneal neurotization are starting to be described in ophthalmic literature. Several options are available for surgically managing the complications of herpes keratitis. Ophthalmologists should select the optimal procedure based on the individual patient's situation. VIDEO ABSTRACT: http://links.lww.com/COOP/A28.

Emergency cricothyrotomy-a comparative study of different techniques in human cadavers.

PubMed

Schober, Patrick; Hegemann, Martina C; Schwarte, Lothar A; Loer, Stephan A; Noetges, Peter

2009-02-01

Emergency cricothyrotomy is the final lifesaving option in "cannot intubate-cannot ventilate" situations. Fast, efficient and safe management is indispensable to reestablish oxygenation, thus the quickest, most reliable and safest technique should be used. Several cricothyrotomy techniques exist, which can be grouped into two categories: anatomical-surgical and puncture. We studied success rate, tracheal tube insertion time and complications of different techniques, including a novel cricothyrotomy scissors technique in human cadavers. Sixty-three inexperienced health care providers were randomly assigned to apply either an anatomical-surgical technique (standard surgical technique, n=18; novel cricothyrotomy scissors technique, n=14) or a puncture technique (catheter-over-needle technique, n=17; wire-guided technique, n=14). Airway access was almost always successful with the anatomical-surgical techniques (success rate in standard surgical group 94%, scissors group 100%). In contrast, the success rate was smaller (p<0.05) with the puncture techniques (catheter-over-needle group 82%, wire-guided technique 71%). Tracheal tube insertion time was faster overall (p<0.05) with anatomical-surgical techniques (standard surgical 78s [54-135], novel cricothyrotomy scissors technique 60s [42-82]; median [IQR]) than with puncture techniques (catheter-over-needle technique 74s [48-145], wire-guided technique 135s [116-307]). We observed fewer complications with anatomical-surgical techniques than with puncture techniques (p<0.001). In inexperienced health care personnel, anatomical-surgical techniques showed a higher success rate, a faster tracheal tube insertion time and a lower complication rate compared with puncture techniques, suggesting that they may be the techniques of choice in emergencies.

Transanal repair of rectocele and full rectal mucosectomy with one circular stapler: a novel surgical technique.

PubMed

Regadas, F S P; Regadas, S M M; Rodrigues, L V; Misici, R; Silva, F R; Regadas Filho, F S P

2005-04-01

We present a new surgical stapling technique for treatment of rectocele when associated with internal mucosal prolapse or haemorrhoids using only one circular mechanical stapler. Eight female patients, mean age 53 years (range, 42-70), complaining of obstructed defecation with vaginal digitation because of rectocele associated with internal mucosal prolapse underwent transanal repair of rectocele and rectal mucosectomy using one circular stapler between April and July 2004. A running horizontal mattress suture was placed through the base of the rectocele including mucosa, submucosa and the muscle layer of the whole anterior anorectal junction wall. The prolapsed mucosa and the muscular layer were then excised with an electrical scapel. A continuous pursestring rectal mucosa suture was placed 0.5 cm before the previous anterior mucosa and muscle layers resected wound, including the anorectal junction wall which was kept separate from the posterior vaginal wall by a Babcock forceps. Posteriorly, the pursestring suture included only mucosal and submucosal layers. The stapled suture was positioned between normal anterior rectal wall and the anal canal, 0.5 cm above the pectinate line. The stapler was then closed, fired and withdrawn. One patient complained of a perianal hematoma on the seventh postoperative day, requiring surgical excision. Postoperative defecography showed correction of the rectocele and outlet obstruction disappeared in all patients. This novel combined manual-stapled technique for rectocele and rectal internal mucosal prolapse seems to be a safe procedure and the preliminary results are encouraging. Further investigations have to be performed to assess long-term outcome in a larger number of patients.

Surgical techniques on periodontal plastic surgery and soft tissue regeneration: consensus report of Group 3 of the 10th European Workshop on Periodontology.

PubMed

Sanz, Mariano; Simion, Massimo

2014-04-01

The scope was to review the three main clinical indications in periodontal plastic surgical procedures. To review the fundamental principles in periodontal plastic surgery, the main surgical designs in flap surgery applied to the treatment of recessions, peri-implant soft tissue deficiencies and soft tissue ridge augmentation, as well as the surgical principles of using autologous connective tissue grafts and soft tissue substitutes. In the pre-operative phase, the key elements are the control of prognostic factors affecting the patient, namely oral hygiene, tobacco smoking cessation and systemic disease control. In the operative phase, the principles of flap design, mobilization, advancement, adaptation and stabilization. In the post-operative phase infection control, including effective oral hygiene measures, antiseptic treatment and other medications. In single recession defects, the most widely used flap technique is the coronally advanced flap and in specific clinical situations the laterally positioned flap. In multiple recession defects, the number of defects and their location and depth guide the surgical design, being one design with and the other without vertical releasing incisions. When flaps are used in combination with grafts the tunnel flap is also used extensively. The key elements are the donor site selection and harvesting technique, its tissue integration and volume stability. Given the current evidence, various clinical recommendations on the use of flaps and grafts are provided. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.