The role of cognitive abilities in laparoscopic simulator training

Learning minimally invasive surgery (MIS) differs substantially from learning open surgery and trainees differ in their ability to learn MIS. Previous studies mainly focused on the role of visuo-spatial ability (VSA) on the learning curve for MIS. In the current study, the relationship between spatial memory, perceptual speed, and general reasoning ability, in addition to VSA, and performance on a MIS simulator is examined. Fifty-three laparoscopic novices were tested for cognitive aptitude. Laparoscopic performance was assessed with the LapSim simulator (Surgical Science Ltd., Gothenburg, Sweden). Participants trained multiple sessions on the simulator until proficiency was reached. Participants showed significant improvement on the time to complete the task and efficiency of movement. Performance was related to different cognitive abilities, depending on the performance measure and type of cognitive ability. No relationship between cognitive aptitude and duration of training or steepness of the learning curve was found. Cognitive aptitude mediates certain aspects of performance during training on a laparoscopic simulator. Based on the current study, we conclude that cognitive aptitude tests cannot be used for resident selection but are potentially useful for developing individualized training programs. More research will be performed to examine how cognitive aptitude testing can be used to design training programs

Towards automated visual flexible endoscope navigation

Background:\ud The design of flexible endoscopes has not changed significantly in the past 50 years. A trend is observed towards a wider application of flexible endoscopes with an increasing role in complex intraluminal therapeutic procedures. The nonintuitive and nonergonomical steering mechanism now forms a barrier in the extension of flexible endoscope applications. Automating the navigation of endoscopes could be a solution for this problem. This paper summarizes the current state of the art in image-based navigation algorithms. The objectives are to find the most promising navigation system(s) to date and to indicate fields for further research.\ud Methods:\ud A systematic literature search was performed using three general search terms in two medical–technological literature databases. Papers were included according to the inclusion criteria. A total of 135 papers were analyzed. Ultimately, 26 were included.\ud Results:\ud Navigation often is based on visual information, which means steering the endoscope using the images that the endoscope produces. Two main techniques are described: lumen centralization and visual odometry. Although the research results are promising, no successful, commercially available automated flexible endoscopy system exists to date.\ud Conclusions:\ud Automated systems that employ conventional flexible endoscopes show the most promising prospects in terms of cost and applicability. To produce such a system, the research focus should lie on finding low-cost mechatronics and technologically robust steering algorithms. Additional functionality and increased efficiency can be obtained through software development. The first priority is to find real-time, robust steering algorithms. These algorithms need to handle bubbles, motion blur, and other image artifacts without disrupting the steering process

Mid-term Fixation Stability of the EndoVascular Technologies Endograft

AbstractAim of the study to determine the positional stability of the EndoVascular Technologies (EVT) endograft after endovascular aneurysm repair during morphologic changes of the abdominal aorta during follow-up. Patients and methods all patients treated worldwide with an EVT endograft with an adequate postoperative and at least 12 months postoperative CT scan were included (n=125). Endograft migration was investigated by recording the position of the endograft attachment systems relative to the renal arteries and the aortic or iliac bifurcations. The vertical body axis served as a scale to quantify migration. Aortic cross-sectional areas were measured in the suprarenal aorta and in the proximal and distal aneurysm necks. Length changes of the infrarenal aorta during follow-up were measured, comparing the distance between the left renal artery and the aortic bifurcation. Results the median follow-up was 24 months (range 12–48 months). Graft migration was identified in 4 out of 125 patients (3%). Significant infrarenal aortic dilation was observed at the proximal and distal aneurysm neck during follow-up. However, aortic neck dilation was not associated with endograft migration. The length of the infrarenal aorta did not change significantly after endovascular repair. Conclusion fixation by stents containing hooks of the EVT design appear to be effective in preventing migration of endografts with an unsupported trunk for up to four years. A stable position was maintained in spite of changes in cross-sectional areas of the aneurysm neck

Robot-assisted laparoscopic rectovaginopexy for rectal prolapse: a prospective cohort study on feasibility and safety

Robotic systems may be particularly supportive for procedures requiring careful pelvic dissection and suturing in the Douglas pouch, as in surgery for rectal prolapse. Studies reporting robot-assisted laparoscopic rectovaginopexy for rectal prolapse, however, are scarce. This prospective cohort study evaluated the outcome of this technique up to one year after surgery. From January 2005 to June 2006, 15 consecutive patients with a rectal prolapse, either with or without a concomitant rectocele or enterocele, underwent robot-assisted laparoscopic rectovaginopexy with support of the da Vinci robotic system. A prospective cohort study was performed on operating times, blood loss, intra-operative and post-operative complications, and outcome at a minimum of one year after surgery. Median age at time of operation was 62 years (33-72) and median body mass index 24.9 (20.9-33.9). Median robot set-up time was 10 min (3-15) and median skin-to-skin operating time was 160 min (120-180). No conversions to open surgery were necessary. No in-hospital complications occurred and there was no mortality. Median hospital stay was four days (2-9). During one year follow-up, two patients needed surgical reintervention. One patient was operated for recurrent enterocele and rectocele one week after surgery. In another patient an incisional hernia at the camera port occurred three months after surgery. At one year after surgery, 87% of patients claimed to be satisWed with their postoperative result. Robot-assisted laparoscopic rectovaginopexy proved to be an eVective technique with favourable outcomes in most patients in this prospective series. The operating team experienced the support of the robotic system as beneWcial, especially during the dissection of the rectovaginal plane and suturing in the Douglas pouch