Abstrakt Technologie Září 2010

“Laparoendoscopic Single-site and Natural Orifice Transluminal Endoscopic Surgery in Urology: A Critical Analysis of the Literature.”

Autorino, R., J. A. Cadeddu, et al. (2010).

European Urology.


Context: Natural orifice transluminal endoscopic surgery (NOTES) and laparoendoscopic single-site surgery (LESS) have been developed to benefit patients by enabling surgeons to perform scarless surgery. Objective: To summarize and critically analyze the available evidence on the current status and future perspectives of LESS and NOTES in urology. Evidence acquisition: A comprehensive electronic literature search was conducted in June 2010 using the Medline database to identify all publications relating to NOTES and LESS in urology. Evidence synthesis: In urology, NOTES has been completed experimentally via transgastric, transvaginal, transcolonic, and transvesical routes. Initial clinical experience has shown that NOTES urologic surgery using currently available instruments is indeed possible. Nevertheless, because of the immaturity of the instrumentation, early cases have demanded high technical virtuosity. LESS can safely and effectively be performed in a variety of urologic settings. As clinical experience increases, expanding indications are expected to be documented and the efficacy of the procedure to improve. So far, the quality of evidence of all available studies remains low, mostly being small case series or case-control studies from selected centers. Thus, the only objective benefit of LESS remains the improved cosmetic outcome. Prospective, randomized studies are largely awaited to determine which LESS procedures will be established and which are unlikely to stand the test of time. Technology advances hold promise to minimize the challenging technical nature of scarless surgery. In this respect, robotics is likely to drive a major paradigm shift in the development of LESS and NOTES. Conclusions: NOTES is still an investigational approach in urology. LESS has proven to be immediately applicable in the clinical field, being safe and feasible in the hands of experienced laparoscopic surgeons. Development of instrumentation and application of robotic technology are expected to define the actual role of these techniques in minimally invasive urologic surgery. © 2010 European Association of Urology.




“Pure and hybrid natural orifice transluminal endoscopic surgery (NOTES): Current clinical experience in urology.”

Autorino, R., G. P. Haber, et al. (2010).

BJU International 106(6 PART B): 919-922.


An exciting era of discovery in the field of scarless urological surgery has just begun. Hybrid natural orifice transluminal endoscopic surgery (NOTES) nephrectomy has been reported by a few groups in the last two years. Recently, our group at the Cleveland Clinic was able to demonstrate the feasibility of a transvaginal pure NOTES nephrectomy. During this pioneering period, a critical appraisal of results and a scrupulous determination of benefits are of utmost importance. Further studies are awaited to define the actual role of NOTES in the management of urological diseases. © 2010 BJU INTERNATIONAL.




“Traditional Versus Single-site Placement of Adjustable Gastric Banding: A Comparative Study and Cost Analysis.”

Ayloo, S. M., N. C. Buchs, et al. (2010).

Obesity Surgery.


In bariatric surgery, laparoscopic adjustable gastric banding (LAGB) has proven effective in reducing weight and improving obesity-associated comorbidities. Recently, however, laparoendoscopic single-site (LESS) surgery has been proposed to minimize the invasiveness of laparoscopic surgery. The aim of this study is to compare the operative cost and peri-operative outcomes of these two approaches. We undertook a retrospective review of a prospectively maintained database of patients undergoing either LAGB or LESS between March 2006 and October 2009. The outcomes and cost of 25 LESS gastric bandings were compared to 121 standard LAGB. Costs included operative time, consumables, and laparoscopic tower depreciation. Both groups had similar patient demographics, body mass index, and comorbidities; with the exception of age (37 year for single site vs. 44 years for standard; P = 0.002). There were no statistical differences for operative time (78 vs. 76 min, P = 0.69), blood loss (8.4 vs. 9 ml, P = 0.76), pain score (0.81 vs. 0.84 at 1 week, P = 0.95) or complication rates (12% vs. 14%, P = 1). Length of stay was shorter for the LESS group (0.5 day vs. 1.5 days, P = 0.02). The mean operative cost for the LESS banding was $20,502/case vs. $20,346/case for the standard LAGB, with no statistically significant difference between the approaches (P = 0.73). Operative costs and peri-operative outcomes of LESS gastric banding are comparable with those of the standard LAGB procedure. As a result, single-site surgery can be proposed as a valid alternative to the standard procedure with cosmetic advantage and comparable complication rate.




“Laparoendoscopic single-site surgery: Complications and how to avoid them.”

Berkowitz, J. R. and M. E. Allaf (2010).

BJU International 106(6 PART B): 903-907.


INTRODUCTION: Laparoendoscopic single-site surgery (LESS) has emerged as a natural progression from standard laparoscopy aiming to further minimize the morbidity of urological procedures. Recent advances in technology and instrumentation coupled with a mastery of laparoscopic surgery by some has led to the incorporation of LESS techniques in a variety of complex urological operations. Given the paucity of published data regarding complications, we review the collective experience as well as share our own results and observations. METHODS: A literature search of published series on LESS was performed focusing on complications and other difficulties associated with this new technique. The experience with LESS at our institution was also evaluated for complications and means of avoiding them. RESULTS: A few complications relating to LESS specifically are reported in the literature. These are generally related to the access site and the ability to manage situations that require added dexterity. Conversion to standard laparoscopy (or open surgery) is rare while insertion of an additional port appears to be more common. CONCLUSIONS: LESS is an evolving platform and may have a steeper learning curve than standard laparoscopy. In experienced hands, the rates of LESS complications appear to be similar to other surgical techniques. © 2010 BJU INTERNATIONAL.




“Laparoendoscopic single-site surgery and natural orifice transluminal endoscopic surgery: Future perspectives.”

Best, S. L., C. R. Tracy, et al. (2010).

BJU International 106(6 PART B): 941-944.


Hundreds of laparoendoscopic single-site surgery (LESS) and natural orifice transluminal endoscopic surgery (NOTES) cases have been reported in the literature across a broad span of urological procedures. Despite this, many hurdles to widespread adoption of these techniques exist, including technical challenges, such as decreased triangulation and unfamiliar viewing angles, and more philosophical issues, such as the necessity of demonstrating benefits of these techniques over conventional laparoscopy. Future research will seek to overcome these obstacles. This may be accomplished with further instrument development, including robotic instrumentation, as well as clinical studies evaluating outcomes of LESS/NOTES operations that may demonstrate advantages in these techniques. © 2010 BJU INTERNATIONAL.




“Scarless Single-Port Laparoscopic Pelvic Kidney Nephrectomy.”

Brown, C. T., G. Kooiman, et al. (2010).

Journal of Laparoendoscopic and Advanced Surgical Techniques. Part A.


Abstract Introduction: We report the first pelvic kidney removal through the umbilicus using a scarless pure single-port technique in a young woman. Patients and Methods: A 27-year-old woman presented with uro-sepsis and acute renal failure secondary to a dilated, chronically infected, nonfunctioning left-sided pelvic kidney with ureteropelvic obstruction causing an obstruction to the right kidney. The acute episode was managed with bilateral ureteric stents and antibiotics. Definitive treatment involved removal of the diseased pelvic kidney through the umbilicus via a single-port access device (TriPor™; Olympus). A curved tissue grasper and extralong bariatric suction device were used along with standard straight laparoscopic instruments. In addition, a 10-mm flexible-tip video laparoendoscope (HD EndoEYE LTF-VH™; Olympus) and a robotic camera holder (FreeHand™; Prosurgics) were used to reduce external instrument clash. Results: The procedure was technically successful leaving the patient with a scarless abdomen. The operative time was 185 minutes, blood loss 100 mL, and length of stay 48 hours. There were no complications. Conclusion: Scarless transumbilical pelvic nephrectomy is technically feasible. The first reported clinical experience is discussed.




“Single-port risk-reducing salpingo-oophorectomy with and without hysterectomy: Surgical outcomes and learning curve analysis.”

Escobar, P. F., D. C. Starks, et al. (2010).

Gynecologic Oncology 119(1): 43-47.


Objective: Based on considerable prospective data, risk-reducing salpingo-oophorectomy (RRSO) is one of the most beneficial interventions available to reduce ovarian/breast cancer risk in BRCA carriers and high-risk women. The purpose of this study was to describe the initial surgical outcomes and learning curve analysis associated with laparoendoscopic single-site (LESS) RRSO with and without hysterectomy. Methods: A retrospective, multi-institutional analysis of BRCA carriers and women at high risk for breast/ovarian cancer who underwent LESS RRSO with and without hysterectomy in 2009 was performed. Data collected included age, BMI, procedure, operative time, length of hospital stay, postoperative pain scores, and post operative complications. Student t-test, Pearson correlation coefficient, and multivariate linear regression were used for analysis. Results: A total of 58 patients were evaluated; 36 (63%) were BRCA1/2 carriers and 38 (63%) had breast cancer. Patients’ mean age and BMI were 46 years and 27 kg/m<sup>2</sup>, respectively. Most patients were Caucasian (76%), and at the time of prophylactic surgery, 53% of patients were undergoing active breast cancer treatment. Mean operative time was 38.1 minutes (16-80 minutes). All cases were performed successfully via the LESS approach, and there were no surgical complications. Multivariate linear regression analysis was done, and after controlling for study site, previous abdominal surgery, active cancer treatment, and BMI, operative time was only influence by number of cases performed, p = 0.019. Conclusions: LESS RRSO is feasible and safe with favorable surgical and cosmetic outcomes. In our experience, surgical proficiency is possible after 10-15 cases. The LESS approach may be ideal for BRCA mutation carriers and breast cancer patients because of a short convalescence, permitting minimal interruption in any ongoing cancer treatment and the potential psychological benefits from improved cosmesis and pain control. Prospective studies are needed to assess the relative benefits of LESS compared with more conventional minimally invasive approaches. © 2010 Elsevier Inc.




“Single-incision laparoscopic surgery (SILS) in general surgery: A review of current practice.”

Froghi, F., M. H. Sodergren, et al. (2010).

Surgical Laparoscopy, Endoscopy and Percutaneous Techniques 20(4): 191-204.


Single-incision laparoscopic surgery (SILS) aims to eliminate multiple port incisions. Although general operative principles of SILS are similar to conventional laparoscopic surgery, operative techniques are not standardized. This review aims to evaluate the current use of SILS published in the literature by examining the types of operations performed, techniques employed, and relevant complications and morbidity. This review considered a total of 94 studies reporting 1889 patients evaluating 17 different general surgical operations. There were 8 different access techniques reported using conventional laparoscopic instruments and specifically designed SILS ports. There is extensive heterogeneity associated with operating methods and in particular ways of overcoming problems with retraction and instrumentation. Published complications, morbidity, and hospital length of stay are comparable to conventional laparoscopy. Although SILS provides excellent cosmetic results and morbidity seems similar to conventional laparoscopy, larger randomized controlled trials are needed to assess the safety and efficacy of this novel technique. Copyright © 2010 by Lippincott Williams & Wilkins.




“Rationale for natural orifice transluminal endoscopic surgery and current limitations.”

Granberg, C. F. and M. T. Gettman (2010).

BJU International 106(6 PART B): 908-912.


Over the past several years, surgeons have sought to develop techniques to decrease the morbidity of various procedures. As a result, an extensive array of progressively more minimally invasive techniques now exists in the urologist’s armamentarium, including smaller (‘mini’) incisions, laparoscopic hand-assisted surgery, as well as pure laparoscopic and robotic approaches. Theoretically, smaller incisions result in decreased pain and subsequently accelerated convalescence postoperatively. Most recently, innovative surgeons across multiple surgical specialties have pioneered the concept of eliminating incisions altogether and operating through natural orifices, which has been termed natural orifice transluminal endoscopic surgery (NOTES). The improved cosmesis associated with a pure NOTES approach is an attractive option for patients undergoing invasive therapeutic and diagnostic procedures. NOTES has significant potential for use by urological surgeons, as evidenced by multiple studies demonstrating the feasibility of pure and hybrid NOTES procedures in cadaveric, animal and human subjects. The purpose of this paper is to review the rationale for NOTES in urological surgery, and to detail the current limitations of this new technique. © 2010 BJU INTERNATIONAL.




“Robotic single-incision transabdominal and transvaginal surgery: initial experience with intersecting robotic arms.”

Hagen, M. E., O. J. Wagner, et al. (2010).

Int J Med Robot 6(3): 251-255.


BACKGROUND: Single-incision laparoscopic and natural orifice translumenal endoscopic surgery (NOTES) are technically challenging methods. Robotics might have the potential to overcome such hurdles with computer technology. METHODS: The da Vinci Standard and S System (Intuitive, Sunnyvale, USA) were used in human cadavers and pigs to perform single-incision transabdominal and transvaginal surgery. Robotic arms were crossed and control-switched to achieve intuitive control. RESULTS: It was possible to perform robotic single-incision laparoscopy in the typical, intuitive fashion. Transvaginal set-up, including docking of the system and introduction of instruments into the abdominal cavity, was possible but no useful manipulation could be performed. CONCLUSIONS: While robotic NOTES with the da Vinci surgical system was not successful, robotic single-incision surgery is feasible using the above set-up. This new approach seems to offer the advantages of single-incision surgery while maintaining the intuitive control of robotic surgery. Clinical application appears justified.




“The feasibility of scarless single-port transumbilical total laparoscopic hysterectomy: Initial clinical experience.”

Jung, Y. W., Y. T. Kim, et al. (2010).

Surgical Endoscopy and Other Interventional Techniques 24(7): 1686-1692.


Objective The purpose of the present study is to demonstrate the feasibility of single-port transumbilical laparoscopic surgery (SPLS) for hysterectomy and elaborate on our experience in order to introduce the single-port approach for gynecologic surgery. Methods Between August 2008 and February 2009, 30 patients who initially planned to undergo single-port laparoscopic surgery at Yonsei University Health System in Seoul, Korea were enrolled in this study. The authors used a single-port three-channel system with a wound retractor, surgical gloves, and one 10/11-mm and two 5-mm trocars. All surgical procedures were performed with 30°, 5-mm laparoscope, conventional laparoscopic instruments, and the LigaSureTM system (Valleylab, Boulder, CO, USA). Patient characteristics and surgical outcomes were prospectively evaluated. A visual analog score (VAS) scale was used to measure postoperative pain. Results Twenty-nine of 30 patients underwent single-port laparoscopic surgery without conversion to laparotomy or conventional laparoscopic hysterectomy. Median operative time was 100 min (57-155 min), median blood loss was 100 ml (10-400 ml), median postoperative hospital stay was 3 days (2-6 days), and median weight of resected uteri was 167 g (45-482 g). VAS scoring of pain at 6, 24, and 48 h after surgery was 4, 3, and 2, respectively. There were no operative complications. Conclusion SPLS is a feasible approach for hysterectomy in terms of operative time, complication rates, and cosmetic results. However, the possible benefits for patients such as better cosmetic outcomes, reduced pain, and lower complication rates should be evaluated in randomized prospective studies. © Springer Science+Business Media, LLC 2009.




“Introduction: Less and notes surgery in urology.”

Kaouk, J. H. (2010).

BJU International 106(6 PART B): 885.




“Laparoendoscopic single-site surgery: Current clinical experience.”

Khanna, R., R. Autorino, et al. (2010).

BJU International 106(6 PART B): 897-902.




“Psychosocial and marketing challenges for natural orifice transluminal endoscopic surgery and laparoendoscopic single-site surgery.”

Kommu, S. S., R. Dasgupta, et al. (2010).

BJU International 106(6 PART B): 928-933.




“Single-incision laparoscopic cholecystectomy: Initial evaluation of a large series of patients.”

Rivas, H., E. Varela, et al. (2010).

Surgical Endoscopy and Other Interventional Techniques 24(6): 1403-1412.


Background Findings have shown that single-incision laparoscopic cholecystectomy (SILC) is feasible and reproducible. The authors have pioneered a two-trocar SILC technique at the University of Texas Southwestern. Their results for 100 patients are presented. Methods From January 2008 to March 2009, 100 patients with symptomatic gallbladder disease underwent SILC through a 1.5- to 2-cm umbilical incision using a two-port (5-mm) technique. For nearly all the patients, a 30° angled scope was used. The gallbladder was retracted, with two or three sutures placed along the gallbladder. These sutures were either fixated internally or placed through the abdominal wall to obtain a critical view of Calot’s triangle. The SILC procedure was performed using standard technique with 5-mm reticulating or conventional laparoscopic instruments. The cystic duct and artery were well visualized, clipped, and divided. Cholecystectomy was completed with electrocautery, and the specimen was retrieved through the umbilical incision. Results In this series, 80 women (85%) and 15 men (15%) with an average age of 33.8 years (range, 17-66 years) underwent SILC. Their mean BMI was 29.8 kg/m<sup>2</sup> (range, 17-42.5 kg/m<sup>2</sup>), and 39% of these patients had undergone previous abdominal surgery. The mean operative time was 50.8 min (range, 23-120 min). The mean estimated blood loss was 22.3 ml (range, 5-125 ml), and 5% of the patients had an intraoperative cholangiogram. There were no conversions of the SILC technique. A two-trocar technique was feasible for 87% of the patients. For the remaining patients, either a three-channel port or three individual trocars were required. A SILC technique was used for 5% of the patients to manage acute cholecystitis or gallstone pancreatitis. Conclusion The SILC technique with a two-trocar technique is safe, feasible, and reproducible. The operating times are reasonable and can be lessened with experience. Even complex cases can be managed with this technique. Excellent exposure of the critical view was obtained in all cases. The SILC procedure is becoming the standard of care for most of the authors’ elective patients with gallbladder disease. Clinical trials are warranted before the SILC technique is adopted universally. © The Author(s) 2009.




“Single-port laparoscopic umbilical hernia repair.”

Roberts, K. E., L. Panait, et al. (2010).

Surgical Innovation 17(3): 256-260.


Background: Laparoscopic umbilical herniorrhaphy is preferred when abdominal wall defects exceed 3 cm. The authors describe a novel single-port laparoscopic technique for umbilical hernia repair. Methods: A total of 10 patients underwent single-port laparoscopic umbilical hernia repair. A 10-mm endoscope with a working channel was placed in the left upper quadrant. The abdominal wall defect was covered with a circular mesh with pretied sutures and needles attached. The mesh was secured to the abdominal wall with intraabdominal sutures without the need for transfascial suture fixation. Results: The average age of the patients was 43 years, and the average BMI was 34 kg/m<sup>2</sup>. All procedures were completed laparoscopically. The mean operative time was 73 minutes. No major intraoperative or postoperative complications were encountered. Conclusions. Single-port laparoscopic umbilical hernia repair is a safe and easily reproducible novel technique. It can help reduce possible complications from multiple-port sites. © The Author(s) 2010.




“Single-port laparoscopic cholecystectomy: Initial experience.”

Romanelli, J. R., T. B. Roshek Iii, et al. (2010).

Surgical Endoscopy and Other Interventional Techniques 24(6): 1374-1379.


Background As surgeons embrace the concept of increasingly less invasive surgery, techniques using only a single small incision have begun to gain traction. Several commercially available products have emerged recently. The TriPortTM system and the SILSTM Port are single-port devices that allow the surgeon to perform laparoscopic surgery through a 2- to 3-cm periumbilical incision. This study aimed to ascertain whether these devices allow safe and reliable access for laparoscopic cholecystectomy. Methods From March 2008 to June 2009, single-port laparoscopic cholecystectomy was attempted for 22 patients with an average age of 40 years (range, 23-73 years). The data collected prospectively after institutional review board approval included demographics, operative time, complications, and reasons for conversion to standard four-port laparoscopic surgery. Results The operation was completed successfully for 21 of the 22 patients (15 women and 7 men) using five different techniques. The mean body mass index (BMI) of the patients was 32.7 kg/cm <sup>2</sup> (range, 22.3-46.1 kg/cm<sup>2</sup>). Three of the patients had previously undergone laparoscopic Roux-en-Y gastric bypass. The mean operative time was 80.8 min (range, 51-156 min). One patient experienced a Richter’s hernia postoperatively, which required a reoperation and subsequent bowel resection. One patient required conversion to a standard four-port laparoscopic cholecystectomy because the articulating instrument could not reach the gallbladder from the umbilicus. Conclusion The results from the current series show single-port laparoscopic cholecystectomy to be a promising technique. A variety of patient demographics appear suited to this approach. The operative time in this series compares favorably with that for the standard four-port operation. The feasibility of single-port laparoscopic cholecystectomy is now established. However, routine application of this novel technique requires an evaluation of its safety and cost effectiveness in larger studies. In addition, its superiority over standard laparoscopic cholecystectomy in terms of postoperative pain, cosmesis, and overall patient satisfaction requires further study. Refinements in instrumentation will enable wider use of this novel minimally invasive approach. © Springer Science+Business Media, LLC 2009.




“Current status and prerequisites for natural orifice translumenal endoscopic surgery (NOTES).”

Tomikawa, M., H. Xu, et al. (2010).

Surgery Today 40(10): 909-916.


Natural orifice translumenal endoscopic surgery (NOTES) is a sophisticated form of endoscopic surgery whose use has recently spread rapidly around the world. Although hundreds of reports of animal studies and clinical cases about NOTES have been published since 2004, NOTES is still in the experimental phase. The formation of an iatrogenic incision in the lumenal wall of intraperitoneal organs is a major disadvantage of NOTES. No reliable technique for complete closure has yet been established, and this problem must be resolved before NOTES can be adopted as a routine clinical practice. Several devices for the closure of lumenal incisions in the stomach or colorectum have been developed, and their safety and usefulness have been examined in animal studies and clinical cases. Kyushu University has been involved in furthering the adoption of NOTES as a routine clinical practice, and the Kyushu University Training Center for Minimally Invasive Surgery holds training sessions on endoscopic surgical techniques for surgeons from all over Japan. Studies to develop a navigation system and robotic technology for use with NOTES are also in progress at Kyushu University. The further development of endoscopy-related technologies and equipment, such as robotic technology, is therefore essential to allow the safe, widespread adoption of pure NOTES.




“Robotic laparoendoscopic single-site surgery.”

White, M. A., G. P. Haber, et al. (2010).

BJU International 106(6 PART B): 923-927.


Laparoscopic surgery is frequently used in urology and the introduction of the da Vinci surgical system has served to further increase the demand for these procedures. Yet, laparoscopy is not without its drawbacks including port site complications, such as bleeding, hernia, internal organ damage and scarring. To further decrease morbidity of standard laparoscopy, newer techniques such as laparoendoscopic single-site surgery (LESS) are currently being investigated. LESS is technically challenging and reduces instrument triangulation and robust retraction, and is associated with a steep learning curve. To help overcome current limitations we have introduced the da Vinci surgical system to LESS and report our experience with robotic laparoendoscopic single-site surgery. © 2010 BJU INTERNATIONAL.




“Three-dimensional visualisation improves understanding of surgical liver anatomy.”

Beermann, J., R. Tetzlaff, et al. (2010).

Medical Education 44(9): 936-940.


OBJECTIVES: Three-dimensional (3-D) representation is thought to improve understanding of complex spatial interactions and is being used more frequently in diagnostic and therapeutic procedures. It has been suggested that males benefit more than females from 3-D presentations. There have been few randomised trials to confirm these issues. We carried out a randomised trial, based on the identification of complex surgical liver anatomy, to evaluate whether 3-D presentation has a beneficial impact and if gender differences were evident. METHODS: A computer-based teaching module (TM) was developed to test whether two-dimensional (2-D) computed tomography (CT) images or 3-D presentations result in better understanding of liver anatomy. Following a PowerPoint lecture, students were randomly selected to participate in computer-based testing which used either 2-D images presented as consecutive transversal slices, or one of two 3-D variations. In one of these the vessel tree of portal and hepatic veins was shown in one colour (3-D) and in the other the two vessel systems were coloured differently (3-Dc). Participants were asked to answer 11 medical questions concerning surgical anatomy and four questions on their subjective assessment of the TM. RESULTS: Of the 160 Year 4 and 5 medical students (56.8% female) who participated in this prospective randomised trial, students exposed to 3-D presentation performed significantly better than those exposed to 2-D images (p < 0.001). Comparison of the number of correct answers revealed no significant differences between the 3-D and 3-Dc modalities p > 0.1). Male students gave significantly more correct answers in the 3-D and 3-Dc modalities than female students (p < 0.03). The gender difference observed in both 3-D modalities was not evident in the 2-D group (p = 0.21). CONCLUSIONS: This study showed that 3-D imaging significantly improved the identification of complex surgical liver anatomy. Male students benefited significantly more than female students from 3-D presentations. Use of colour in 3-D presentation did not improve student performance. © 2010 Blackwell Publishing Ltd.




Kelouwani, S., P. Boucher, et al. (2010).

Architecture for human-robot collaborative navigation.


Various situations of mobile platform navigation controls require a collaboration between a human agent and autonomous navigation modules. This work presents a new approach for collaborative control between such two agents, based upon a three-layer architecture. An arbitration scheme is proposed in the deliberative layer as well as a collaborative planning method for trajectory following based upon optimal control theory in the sequencer layer. The collaborative control signal in the execution layer is a weighted summation of each agent control signal. This collaborative architecture could be used for the shared control of vehicles such as motorized wheelchairs. Experimental results illustrate the efficiency of the proposed control architecture.




“Kinematics of a robotic 3UPS1S spherical wrist designed for laparoscopic applications.”

Navarro, J. S., N. Garcia, et al. (2010).

Int J Med Robot 6(3): 291-300.


BACKGROUND: Current robotic orientation surgical devices used to be large, in order to cover the needed workspace and to be rigid enough to resist the forces that occur during surgery. The disadvantages of the large size of the devices are the ergonomics, collisions and interference with the surgeons. This paper presents the first steps that have been carried out on the development of a small spherical wrist for laparoscopic applications. METHODS: Screw theory for kinematic analysis and the design of parallel robots have been used for choosing the kinematic architecture of the first prototype of the laparoscopic wrist. The kinematic equations of the platform are described and the Jacobian matrix calculated. RESULTS: The kinematics of this device is a 3UPS-1S parallel architecture. The work presented here shows the concept of the device, its design, that it was made under intrinsic safety criteria, its kinematic analysis and the first results and images of the built prototype. The kinematic analysis is made using screw theory and it is used to verify the optimization of the design. CONCLUSIONS: A new design for a smart and small spherical wrist is developed. Ergonomics for the surgical team is a design criterion that should be introduced to the design process for an operating-room robotic tool. Parallel robots architecture can contribute to new devices that fit this criterion.