Image-guided endoscopic surgery: results of accuracy and performance in a multicenter clinical study using an electromagnetic tracking system

Image-guided surgery has recently been described in the literature as a useful technology for improved functional endoscopic sinus surgery localization. Image-guided surgery yields accurate knowledge of the surgical field boundaries, allowing safer and more thorough sinus surgery. We have previously reviewed our initial experience with The InstaTrak System. This article presents a multicenter clinical study (n=55) that assesses the system's capability for localizing structures in critical surgical sites. The purpose of this paper is to present quantitative data on accuracy and performance. We describe several new advances including an automated registration technique that eliminates the redundant computed tomography scan, compensation for head movement, and the ability to use interchangeable instruments.     

Cholelithiasis--indications for cholecystectomy, papillotomy and gallstone dissolution (author's transl)

Patients under 50 years without risk factors carrying gallstones should be operated upon for the following reasons: (1) These patients will have complications in up to 40% of cases with increasing age; (2) only 18% of patients are without complaints after a duration of this disease of twenty years; (3) mortality of surgery is 1,06% in patients with no other risk factors. Patients at risk for other reasons, with a functional gallbladder and carrying calcium-free stones should be treated with chenodesoxycholic acid. Patients at risk for other reasons carrying residual stones after cholecystectomy, or suffering from stenosis of the papilla, or harboring stones in the choledochus after choledochoduodenostomy should be subjected to endoscopic papillotomy. Patients at risk for other reasons suffering from cholecystolithiasis or choledocholithiasis should be subjected at first to endoscopic papillotomy, and only thereafter to cholecystectomy. This will decrease the risk of surgery.     

Three-dimensional versus two-dimensional video system for the trained endoscopic surgeon and the beginner

Because of the lack of depth perception in current two-dimensional endoscopic video systems, the performance of fine motor movements is impaired. Endoscopic surgeons are generally able to cope with this limitation, and the performance of complex procedures becomes easy with experience. To assess the value of three-dimensional vision, two groups of surgeons, with and without experience in endoscopic surgery, underwent dexterity tests at a simulator. Data from use of two- and three-dimensional video systems were analysed and are discussed in this paper. The three-dimensional system improved the ability to perform endoscopic procedures, particularly when the highest degree of hand-eye coordination was needed. A common sensation of ocular fatigue, related to the prolonged use of this equipment, may limit its usefulness in advanced endoscopic procedures.     

Regression of childhood Barrett's esophageal mucosa by antireflux surgery and bipolar electrocoagulation

The authors report a case of a 13-year-old girl with Barrett's esophagus who underwent antireflux surgery and was subsequently treated with endoscopic thermal coagulation using bipolar electrocoagulation. Follow-up endoscopy 15 months after completion of the endoscopic therapy showed normal esophageal mucosa without intestinal metaplasia. Longer follow-up is needed to assess the long-term effects of endoscopic treatment of the Barrett's mucosa with thermal coagulation, and this procedure should still be considered under investigation.     

Endoscopic sural nerve harvest in the pediatric patient

A technique of endoscopic sural nerve harvest was devised to minimize the donor-site scarring in pediatric patients requiring peripheral nerve-grafting procedures. The harvests were performed under tourniquet control using two 2-cm incisions for access at the lateral malleolus and the midcalf. Endoscopic visualization and blunt dissection of the nerve were achieved with a 4-mm Hopkins telescope with 30-degree angled lens (Karl Storz GmbH, Tuttlingen, Germany) stabilized in an Emory retractor and attached to a video camera. The medial sural nerve was divided in the popliteal fossa proximally under endoscopic visualization. The lateral sural nerve was identified and harvested when present. Between June of 1994 and March of 1995, 18 patients underwent 27 sural nerve harvests using the endoscopic technique. Mean patient age was 3.3 years (range 4 to 197 months). Indications for surgery included obstetrical brachial plexus palsy (12), facial palsy (5), and ulnar nerve neuroma (1). Nerve-graft length harvested ranged from 13 to 41 cm. Mean tourniquet time per limb was 92 minutes. No nerve graft injury was noted on examination under the operating microscope. Postoperative pain, swelling, and ecchymosis were minimal. Donorsite scarring has been aesthetically satisfactory to date.     

Progress in oesophagoscopy. The role of the conventional oesophagoscope as against the supple fibroscope (author's transl)

In the history of endoscopy, laryngologists have played an important role in knowledge of the oesophagus. For those familiar with gastroscopy, the supple fibroscope represents a diagnostic instrument which may be used for observation of the oesophagus with the exception of natural or pathological areas of stenosis. It offers considerable possibilities in the photographic documentation of lesions. It is relatively easy to perform though not completely harmless. The rigid oesophagoscope remains an effective method of investigation of the whole oesophagus, including the oesophageal opening. It remains the best method for the performance of endoscopic surgery and in particular the extraction of foreign bodies. It is not dangerous in the hands of a competent and trained operator. Rather than opposing each other, the two instruments may be seen to be complementary.     

The combined method: a novel access technique for fetal endoscopic surgery

BACKGROUND/PURPOSE: To develop practical and less invasive techniques for fetal endoscopic surgery, new methods of lifting the uterine wall to allow fetal surgery without maternal laparotomy were developed and assessed. METHODS: Fetal endoscopic surgical procedures, including tracheostomy and umbilical vascular cannulation, were performed using one of the three methods to enter the uterus without maternal laparotomy in pregnant goats (n = 6; 105 to 115 days' gestation): (1) direct uterine lifting with an air-cushion device; (2) indirect uterine lifting, in which the uterine wall was fixed to the maternal abdominal wall using balloon tip ports inserted percutaneously by Seldinger's method, then the maternal abdomen was lifted mechanically; and (3) combined method, in which low pressure CO2 (5 mm Hg for initial inflation and 2 mm Hg for maintenance) was insufflated into the uterus in addition to the indirect uterine lifting cited above. RESULTS: The direct uterine lifting caused massive injury of myometrium and uterine membranes. The creation of intrauterine space and the protection of the membranes were not accomplished effectively by the indirect uterine lifting only. The combined method provided the adequate intrauterine space and excellent endoscopic visibility for completion of the endoscopic procedures with minimal uterine injury. CONCLUSION: The fetal endoscopic surgery may be accomplished simply and safely by the combined method, a novel technique of uterine lifting to allow fetal surgery without maternal laparotomy.     

Electromyographical study on surgeons in urology. I. Influence of the operating technique on muscular strain

An electromyographical field study was performed in the operating theatre on four surgeons during 15 urological operations. In the course of the operations two endoscopic techniques were applied alternately: (1) direct endoscopy, and (2) monitor endoscopy. During direct endoscopy the surgeon looks into the urethra and the bladder via an endoscope. In monitor endoscopy, by contrast, the operating area is observed via a video system consisting of a camera mounted on top of the endoscope and a monitor. During the operations surface electromyograms were derived from both trapezius muscles, the right deltoideus muscle and the left erector spinae muscle. An activity code describing the surgeons' activity was additionally recorded. Analysis of the activity recording reveals that the monitor endoscopic method is preferred in the first third of the operations, whereas preference is given to the direct method in the last third. The electromyographical measurements indicate that during monitor endoscopy the myoelectrical activity of both trapezius muscles and of the right deltoideus muscle is significantly reduced in comparison with the activity for the direct endoscopic technique. A significant influence of the surgical technique on the myoelectrical activity could not be established for the erector spinae muscle. The electromyographical findings reveal that the activity of the shoulder musculature required for the maintenance of the posture and the performance of the operation is significantly lower in monitor endoscopy than in direct endoscopy. Consequently, a clear reduction in muscular strain can be achieved during the performance of endoscopic operations in urology if a video system is employed.     

Sequential intraluminal endoscopic and laparoscopic treatment for bile duct stones associated with gallstones

BACKGROUND: On the basis of a flowchart including prior or current jaundice or pancreatitis, abnormal liver function, ultrasound or IV cholangiography, bile duct (BD) stones were suspected in 71/593 patients referred for gallstones. METHODS: When endoscopic retrograde cholangiography detected BD stones, endoscopic sphincterotomy (ES) and endoscopic BD clearance were attempted, followed by laparoscopic cholecystectomy (LC). BD stones were found in 44/71 patients. The sensitivity values of preoperative conditions were: 92% for IV cholangiography, 88% for abnormal liver function, 50% for ultrasound, and 37% for jaundice at admission. RESULTS: Endoscopic clearance succeeded in 37 patients and LC was completed in 33 patients. Conversion to open surgery (9%) was comparable with the rate in patients without BD stones. The median hospital stay for the sequential endoscopic and laparoscopic treatments was 13 days (range 4-54) or 22 days if open surgery was used. CONCLUSIONS: In conclusion, BD stones can be endoscopically cleared preoperatively in most patients without interfering with LC.     

Treatment of pancreatic stones with extracorporeal lithotripsy with sonographic localization

BACKGROUND: Pancreatic stones may be treated by endoscopic extraction or by surgery. Extracorporeal shock wave lithotripsy increased possibility of noninvasive steps to their elimination. The aim of this study was to describe our first experience with this method. METHOD AND RESULTS: 10 patients (6 men and 4 women) in average age 47 years (between 19 to 72 years) were treated. The lithotriptor MEDILIT with sonographic targeting was used for fragmentation of pancreatic stones. Fragmentation was achieved in 8 patients, in 4 cases we observed spontaneous disappearnace, in 3 cases an endoscopic extraction of fragments was necessary. In one case good fragmentation was observed at control ECRP, but the repeated Wirsungography showed a big pseudocyst which had not been diagnosed at the first examination and surgery was necessary. In 2 cases no fragmentation was achieved and in these cases surgery was also indicated. No serious side effects were observed, nor elevation of amylase values compared with the situation before the shock wave treatment. CONCLUSIONS: Extracorporeal shock wave lithotripsy of pancreatic stones revealed good fragmentation and disappearance stone from ductus Wirsungi without serious side effects on clinical course and surrounding soft tissues.     

An update on peritoneal dialysis and hemodialysis in the pediatric population

Drugs acting as agonists (SKF38393 and quinpirol) or antagonists (SCH23390 and sulpiride) on dopamine receptors were administered at various doses (1, 2 or 4 mg kg-1 day-1) to aged male rats of the Sprague-Dawley strain subjected to labyrinth unilateral lesion. The time course of vestibular compensation was evaluated by recording spontaneous eye nystagmus and by scoring ambulation and rearing with the open field test and motor ability and coordination with the rotorod test. Treatment started 3 days prior to surgery and continued until day 7 after surgery. The vestibular compensation of untreated young male rats was also studied with the same methods. The decline of spontaneous nystagmus in aged animals was slower than that of young rats and was facilitated by the large doses of quinpirol (D2 receptor agonist) and inhibited by sulpiride (D2 receptor antagonist) 4 mg kg-1 day-1, while the other drugs did not affect this parameter. After operation, ambulation and rearing of aged rats increased more slowly as compared to that of young animals. Moreover, motor performance and coordination in aged rats improved less rapidly than those of young controls. Dopamine receptor agonists increased ambulation and improved motor performance and coordination in aged rats, while dopamine receptor antagonists exerted opposite effects. Rearing was not affected by any kind of drug treatment. These results suggest that dopamine neurotransmission plays a role in vestibular compensation process following unilateral labyrinthectomy in aged animals, and this may have clinical relevance in vestibular pathologies of peripheral origin that are associated to brain ageing.     

Effects of camera arrangement on perceptual-motor performance in minimally invasive surgery.

Minimally invasive surgery (MIS) is performed for a growing number of treatments. Whereas open surgery requires large incisions, MIS relies on small incisions through which instruments are inserted and tissues are visualized with a camera. MIS results in benefits for patients compared with open surgery, but degrades the surgeon's perceptual-motor performance. We used a laparoscopic simulator to measure effects of type (top, front, side) and number (1, 3) of camera views on manual manipulation and manual aiming tasks. These experimental manipulations had implications for perceptual and cognitive processing including frame of reference, movement compatibility, compression, task-information specificity, information integration, attentional demands, and information extraction. Camera views generally degraded performance compared with direct viewing, but learning occurred. Generally, a top view resulted in the best performance, followed by front and side views. Benefits of multiple views depended on practice and the direction of grasper movement. Mappings between movement direction and camera view, the consistency of those mappings, and task difficulty affected performance. The benefits and costs for perceptual and cognitive processing that were introduced by a given camera view were not necessarily weighted equally. Costs and benefits must be considered specifically for each task and for each combination of camera view and movement direction. Surgeons may consider using a top view, using side views only when necessary, and using a consistent view when performing repetitive movements. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Evidence-based medicine: a Kuhnian perspective of a transvestite non-theory

Endoscopy has revolutionized the field of aesthetic surgery, permitting the advent of cosmetic surgery via minimal incisions. The procedures are modifications of subperiosteal lifting techniques which grew out of craniofacial surgery. Nonetheless, the cumbersome instrumentation and changes in operator technique have led to the development of a subperiosteal facelift through minimal incisions without the aid of endoscopy. This miniinvasive approach has yielded equivalent results to our endoscopic rhytidectomies in appropriate patients, with reduced morbidity, edema, and operating time. Further, it permits the avoidance of preauricular scars in the majority (84%) of patients; 63 cases are presented, with a follow-up of up to 4 years.     

Endoscopic application in aesthetic and reconstructive facial bone surgery

Twenty-three cases of endoscopically assisted facial bone surgery were performed over the past 3 years. Our series is consistent with 16 cases of aesthetic contouring surgery and 12 treatments of facial bone fracture, including three cases for recontouring of frontal bone, three cases for recontouring of zygoma, endoscopically assisted correction of three zygomatic and blowout fractures, four cases for rhinoplasty and septoplasty for deviated nose, and three cases for mandible contouring surgery. To accomplish this technique, a rigid 4-mm, 30-degree down-angled endoscope was used. The frontal bone or zygomatic arch was approached endoscopically through two or three small incisions on the frontal or temporoparietal scalp. All endoscopic instruments were then manipulated through these incisions. The approach for endoscopically assisted rhinoplasty is the same as with standard rhinoplasty procedures. The approach for zygoma complex and maxillary sinus needs an intraoral incision. Recontouring of zygoma, mandible, and nasal dorsum by an air-driven burr and rasp was performed with endoscopic visual assistance. A plate and screw fixation for zygomatic arch fracture requires an additional small skin incision over the plate for the trocar method. The duration of follow-up ranged from 6 months to 30 months. The postoperative course was satisfactory with a few complications. The extra time needed for the endoscopic procedures was less than 1 hour. Endoscopically assisted facial bone surgery can be performed with adequate visualization and direct manipulation of all facial bones. Complications usually associated with extensive incisions in the bicoronal approach may be avoided. Poor visualization in the conventional approach for operation of orbit, nose, maxillae, and mandible may be avoided by use of the endoscope. This technique may prove to be ideal for aesthetic surgery for facial skeleton with smaller scar and less morbidity.     

A new fine probe for electric cautery during endoscopic surgery

The present paper introduces a new fine probe for electric cautery (1.65 mm in diameter, 22 cm long) that can be connected to a conventional cylindrical hand-controlled cautery holder, which is monopolar and widely used in general surgery. When cautery was required, a 14-gauge intravenous catheter was inserted at an appropriate site under the guidance of a videoscope. After removing the steel inner needle, the extra tube was used as the fine surgical port for the cautery probe. The position of insertion could be altered according to the operating field. Cautery was performed by conventional methods. There was no bleeding or air leakage at the site of puncture during or after surgery. The puncture wound was closed without any sutures. Based on these results, the new fine probe for cautery can reduce the number of surgical ports required for instruments during video-assisted surgery, thus improving the ease and safety of endoscopic surgery.     

Variation in labial shoulder geometry of metal ceramic crown preparations: a finite element analysis

BACKGROUND: The anatomic variation of the frontal sinus and frontal recess can create both a diagnostic and therapeutic challenge. Most cases of frontal sinus disease can now be treated by endoscopic approaches. For refractory cases or those with severe pathology, the microscopically controlled drainage (MCD) operation has at times been successful and spared the patient the morbidity of an external approach. The aim of this study was to evaluate microscopically controlled frontal sinus surgery in these difficult cases. MATERIAL AND METHODS: Prospective analysis was performed on the efficacy of MCD in patients for whom endoscopic sinus surgery had failed or in primary cases with severe pathology or unfavorable anatomy. The technique employs a self-retaining endonasal retractor and a diamond bur under microscopic visualization to remove solid bone (frontal spine) obstructing the sinus drainage and allow a wide opening of the frontal recess while causing minimal mucosal damage. Unilateral drainage (extended frontal sinus drainage operation), and in some cases bilateral drainage (median drainage procedure) is employed. RESULTS: With an average of 23 months of follow-up, over 90% of patients were either free of symptoms or substantially improved after the MCD procedure. Three patients required revision surgery (extend the opening into a median drainage procedure) for adequate relief of symptoms. CONCLUSIONS: The MCD procedure is highly successful in the treatment of frontal recess disease, particularly in those cases of severe pathology or difficult anatomy. It may be used in those cases refractory to standard endoscopic sinus surgery where an external approach and frontal sinus obliteration are contemplated. As with endoscopic sinus surgery, precise knowledge of the frontal recess and neighboring landmarks is critical, and adequate drainage with minimal mucosal disruption should be the goal.     

A simple and safe technique for closure of trocar wounds using a new instrument

An easy and safe method for closing trocar wounds with a new hook-type instrument is presented. The procedure is performed quickly without the need for pneumoperitoneum or a video camera and is done under direct vision.     

Graphical Control Interface for Construction and Maintenance Equipment

This paper discusses graphical interfaces to improve equipment control in construction and facility∕infrastructure maintenance environments. Most large construction and maintenance machines are difficult to control because of insufficient visual feedback to equipment operators. In many emerging applications such as hazardous waste cleaning, it is also necessary to control such equipment from a distance using teleoperation techniques. Initial evidence indicates that real-time updated graphical representation of equipment and work environments can enhance equipment control by providing better spatial perception to the equipment operator. Real-time simulation and task planning with graphical models can also ensure safe and reliable operation of equipment. However, graphical control interfaces require careful design for successful results as it is very difficult to generate exact graphical models of unstructured and dynamic environments such as construction and maintenance. Design of graphical control interfaces for construction equipment also requires knowledge in various technological areas. In this paper, design issues and principles for graphical control interfaces for construction and maintenance equipment are presented. The usefulness of graphical control interfaces is also presented through performance tests of a teleoperated clinker clearing robot for power plant maintenance.     

一种基于背景减法的运动目标检测算法

针对静止摄像机下的运动目标检测问题,提出了一种基于背景减法的运动目标检测算法.首先利用无拘束学习方式迅速建立多个可靠的RGB颜色背景模型,然后在运动目标分割过程中,及时地根据场景变化对背景模型进行更新,同时利用色度信息及局部交叉熵信息去除阴影,得到较为精确的运动目标.在对用普通USB摄像头获取的视频序列实验中,该算法显示了良好的性能.     

智能优化算法在机械故障诊断领域的应用综述

群体智能优化算法是根据生物集群运动、交互、进化等行为机制而开发的自然启发算法,凭借其显著的灵活性、适应性、鲁棒性以及全局寻优能力,被广泛应用于现实世界中各类优化问题的求解. 受羊群间歇性集体运动现象启发,本文提出了一种新的仿生群体智能优化方法—羊群迁徙优化（Sheep flock migrate optimization, SFMO）算法,创新性地建立了3个核心运算模块,即放牧算子、集体运动算子和补偿策略. 与现有的群体智能优化算法相比,SFMO可以通过广泛随机搜索指导下的种群迁徙,降低算法陷于局部最优的概率,为群体智能优化领域提供了一种新的解决方案. 收敛性证明和复杂度分析进一步为SFMO提供了理论支撑. 以CEC-2017基准函数为基础的数值仿真验证表明：SFMO能够有效解决函数优化问题,并在多模态函数优化问题中具有显著优势.