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A.J. Jansen

Bio: A.J. Jansen is an academic researcher from Delft University of Technology. The author has contributed to research in topics: Industrial design & Human power. The author has an hindex of 8, co-authored 23 publications receiving 344 citations.

Papers
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Journal ArticleDOI
TL;DR: It was found that due to mechanical friction losses and variations in the transmission of forces over the working range, the information transmission is far from ideal.
Abstract: SummaryIn laparoscopic surgery, grasping instruments are used to manipulate tissue. These instruments are the only means of contact between tissue and the surgeon's hand. With well designed instruments, the pinching force on the hand should be a reliable measurement for the grasping force on the jaws. To evaluate this transmission of information by the mechanisms of existing grasping instruments, measurements and calculations were carried out. It was found that due to mechanical friction losses and variations in the transmission of forces over the working range, the information transmission is far from ideal. Ways to improve the transmission of information, by adjusting existing instruments or by designing alternative concepts, are indicated.

65 citations

Journal ArticleDOI
TL;DR: The hand-assisted laparoscopic technique was the most efficient and open surgery was the fastest technique, because the time for every surgical motion is a factor of three shorter than for the two laparoscopy techniques.
Abstract: Purpose: To determine the most efficient technique for performing a colectomy, we used the methodology of time-motion analysis. Methods: The efficiency of five hand-assisted and six regular laparoscopic colectomies and one open colectomy, performed by four surgeons in three different hospitals, was measured. The open colectomy was analyzed as a reference procedure. Results and Conclusions: The hand-assisted laparoscopic technique was the most efficient. Hand-assisted laparoscopy was therefore less time consuming than laparoscopic surgery. Open surgery was the fastest technique, because the time for every surgical motion is a factor of three shorter than for the two laparoscopic techniques.

58 citations

Journal ArticleDOI
TL;DR: Time-action analysis was used to evaluate objectively whether instrument positioners can substitute for a surgical assistant efficiently and safely in elective laparoscopic cholecystectomies and showed that the surgeons preferred to operate with an instrument positioner.
Abstract: Background: Instrument positioners can position and lock a laparoscopic instrument. This study uses time-action analysis to evaluate objectively whether IPs can substitute for a surgical assistant efficiently and safely. Methods: In four hospitals, 78 laparoscopic cholecystectomies were randomly assisted by a surgical assistant or an instrument positioner (AESOP and PASSIST) The efficiency and safety of laparoscopic cholecystectomies were analyzed with respect to time, number and type of actions, positioning accuracy, and peroperative complications. A questionnaire evaluated the difficulties for each operation and the comfort of instrument positioner use. Results: The PASSIST and AESOP were able to replace the surgical assistant during laparoscopic cholecystectomies without significantly changing either the efficiency or the safety of the operation. The questionnaire showed that the surgeons preferred to operate with an instrument positioner. Conclusion: This study assessed objectively that instrument positioners can substitute for a surgical assistant efficiently and safely in elective laparoscopic cholecystectomies.

47 citations

Proceedings ArticleDOI
11 May 1999
TL;DR: The decreasing power requirements of consumer electronics combined with an increasing environmental mindedness of consumers and the increasing use of portable electronic products has set the opportunities for human power as a viable alternative to batteries as discussed by the authors.
Abstract: The decreasing power requirements of consumer electronics combined with an increasing environmental mindedness of consumers and the increasing use of portable electronic products has set the opportunities for human power as a viable alternative to batteries. No use of batteries means an environmental benefit as well as a consumer benefit. It will lead to new product concepts offering real portable products that can be used anytime and anywhere.

41 citations

Journal Article
TL;DR: A quantitative analysis method to monitor surgical activities and it was demonstrated that the analysis method is capable of describing different laparoscopic procedures using the limited thesaurus.
Abstract: To support the improvement of advanced laparoscopic surgical procedures, we designed a quantitative analysis method to monitor surgical activities. The emphasis lies on the time spent on these activities and on the instruments controlled by the hands of the surgeon. Our method uses combined video images originating from the laparoscope, an overview CCD camera placed in the operating theatre and, when available, a video colonoscope. After the operation is finished, the images are evaluated by means of a standardised analysis routine based on a spreadsheet program and a set of standard terms (thesaurus), to minimise subjectivity of the analysis. After calculations, the data are presented in tables and graphs, resulting in objective information for research on the operation. Seven advanced laparoscopic procedures, in this case colon resections, have been analysed, and it was demonstrated that the analysis method is capable of describing different laparoscopic procedures using the limited thesaurus. Possible areas of application of the method are the evaluation of time-consuming parts of the operation, of surgical tasks and measurement of the surgeon's learning curve. Other applications are the prediction and measurement of the impact of new instruments and techniques.

39 citations


Cited by
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Journal ArticleDOI
TL;DR: Results indicate that haptic feedback is important during the early phase of psychomotor skill acquisition in virtual reality training, but results seem promising in the area of robot-assisted endoscopic surgical training.
Abstract: Background Virtual reality (VR) as surgical training tool has become a state-of-the-art technique in training and teaching skills for minimally invasive surgery (MIS). Although intuitively appealing, the true benefits of haptic (VR training) platforms are unknown. Many questions about haptic feedback in the different areas of surgical skills (training) need to be answered before adding costly haptic feedback in VR simulation for MIS training. This study was designed to review the current status and value of haptic feedback in conventional and robot-assisted MIS and training by using virtual reality simulation.

469 citations

Journal ArticleDOI
TL;DR: Except for a higher common bile duct injury rate, laparoscopic cholecystectomy appears to be at least as safe a procedure as that of open choleCystectomy.
Abstract: ObjectiveThe purpose of this study was to perform a meta-analysis of large laparoscopic cholecystectomy case-series and compare results concerning complications, particularly bile duct injury, to those reported in open cholecystectomy case-series.Summary Background DataSince the introduction of lapa

416 citations

Journal ArticleDOI
TL;DR: This article gives an overview of research performed in the field of haptic information feedback during minimally invasive surgery (MIS) from 1985 to present and shows that currently, haptic Information feedback is rare, but promising, in MIS.
Abstract: This article gives an overview of research performed in the field of haptic information feedback during minimally invasive surgery (MIS). Literature has been consulted from 1985 to present. The studies show that currently, haptic information feedback is rare, but promising, in MIS. Surgeons benefit from additional feedback about force information. When it comes to grasping forces and perceiving slip, little is known about the advantages additional haptic information can give to prevent tissue trauma during manipulation. Improvement of haptic perception through augmented haptic information feedback in MIS might be promising.

307 citations

Journal ArticleDOI
TL;DR: An scientific and ergonomic approach to the analysis of the operating room environment and the performance and workload characteristics of members of the modern surgical team can provide a rational basis for maximizing the efficiency and safety of the authors' increasingly technology-dependent surgical procedures.
Abstract: This article will provide the reader with an overview of ergonomic issues relevant to the operating room environment. Minimally invasive surgical technologies have increased the therapeutic value of surgical procedures by allowing operations to be performed with less trauma to the patient. At the same time, the surgical team—and particularly the surgeon—have been further removed from direct interaction with the patient's tissues. A scientific and ergonomic approach to the analysis of the operating room environment and the performance and workload characteristics of members of the modern surgical team can provide a rational basis for maximizing the efficiency and safety of our increasingly technology-dependent surgical procedures.

236 citations

Journal ArticleDOI
01 May 2014
TL;DR: A review of the literature dealing with surgical process modelling allows a greater understanding of the SPM field to be gained and introduces future related prospects.
Abstract: Surgery is continuously subject to technological and medical innovations that are transforming daily surgical routines. In order to gain a better understanding and description of surgeries, the field of surgical process modelling (SPM) has recently emerged. The challenge is to support surgery through the quantitative analysis and understanding of operating room activities. Related surgical process models can then be introduced into a new generation of computer-assisted surgery systems. In this paper, we present a review of the literature dealing with SPM. This methodological review was obtained from a search using Google Scholar on the specific keywords: “surgical process analysis”, “surgical process model” and “surgical workflow analysis”. This paper gives an overview of current approaches in the field that study the procedural aspects of surgery. We propose a classification of the domain that helps to summarise and describe the most important components of each paper we have reviewed, i.e., acquisition, modelling, analysis, application and validation/evaluation. These five aspects are presented independently along with an exhaustive list of their possible instantiations taken from the studied publications. This review allows a greater understanding of the SPM field to be gained and introduces future related prospects.

226 citations