Construct validity for eye–hand coordination skill on a virtual reality laparoscopic surgical simulator

Background This study was carried out to investigate whether eye-hand coordination skill on a virtual reality laparoscopic surgical simulator (the LAP Mentor) was able to differentiate among subjects with different laparoscopic experience and thus confirm its construct validity. Methods A total of 31 surgeons, who were all right-handed, were divided into the following two groups according to their experience as an operator in laparoscopic surgery: experienced surgeons (more than 50 laparoscopic procedures) and novice surgeons (fewer than 10 laparoscopic procedures). The subjects were tested using the eye-hand coordination task of the LAP Mentor, and performance was compared between the two groups. Assessment of the laparoscopic skills was based on parameters measured by the simulator. Results The experienced surgeons completed the task significantly faster than the novice surgeons. The experienced surgeons also achieved a lower number of movements (NOM), better economy of movement (EOM) and faster average speed of the left instrument than the novice surgeons, whereas there were no significant differences between the two groups for the NOM, EOM and average speed of the right instrument. Conclusions Eye-hand coordination skill of the nondominant hand, but not the dominant hand, measured using the LAP Mentor was able to differentiate between subjects with different laparoscopic experience. This study also provides evidence of construct validity for eye-hand coordination skill on the LAP Mentor.     

Single-incision laparoscopic surgery (SILS?) versus standard laparoscopic surgery: a comparison of performance using a surgical simulator

Background  

Single-incision laparoscopic surgery (SILS™) is a potentially less invasive approach than standard laparoscopy (LAP). However, SILS™ may not allow the same level of manual dexterity and technical performance compared to LAP. We compared the performance of standardized tasks from the Fundamentals of Laparoscopic Surgery (FLS) program using either the LAP or the SILS™ technique.     

Semiautomatic suturing device (Maniceps®) for laparoscopic surgery

The only automatic device now available to laparoscopic surgeons is Endo-Stitch?, which is costly for single use and has the disadvantage of leaving a large needle hole in the tissue. A semiautomatic suturing device (Maniceps?) for laparoscopic use was developed from a forceps-type of needle holder for open pelvic surgery. The first generation of the instrument was designed for use with the abdominal wall-lift method of laparoscopic surgery, whereas the second generation can be applied for gas insufflation as well. Exchange of the needle is done by an automatic grasping action of a resilient slit in one jaw and by manual pull-down of the needle via the thread onto the other jaw. The new instrument was employed in 10 cases of laparoscopic surgery for various procedures including suture of the perforated gallbladder wall and running suture of the peritoneum after mesh placement in transabdominal repair of inguinal hernia. Maniceps? provides an economic advantage and has the merit of a smaller needle hole. Received: 4 February 1998/Accepted: 18 March 1998     

Warm-up on a simulator improves residents’ performance in laparoscopic surgery: a randomized trial

Introduction and hypothesis

Our aim was to assess the impact of immediate preoperative laparoscopic warm-up using a simulator on intraoperative laparoscopic performance by gynecologic residents.

Methods

Eligible laparoscopic cases performed for benign, gynecologic indications were randomized to be performed with or without immediate preoperative warm-up. Residents randomized to warm-up performed a brief set of standardized exercises on a laparoscopic trainer immediately before surgery. Intraoperative performance was scored using previously validated global rating scales. Assessment was made immediately after surgery by attending faculty who were blinded to the warm-up randomization.

Results

We randomized 237 residents to 47 minor laparoscopic cases (adnexal/ tubal surgery) and 44 to major laparoscopic cases (hysterectomy). Overall, attendings rated upper-level resident performances (postgraduate year [PGY-3, 4]) significantly higher on global rating scales than lower-level resident performances (PGY-1, 2). Residents who performed warm-up exercises prior to surgery were rated significantly higher on all subscales within each global rating scale, irrespective of the difficulty of the surgery. Most residents felt that performing warm-up exercises helped their intraoperative performances.

Conclusion

Performing a brief warm-up exercise before a major or minor laparoscopic procedure significantly improved the intraoperative performance of residents irrespective of the difficulty of the case.     

Construct validity of the LapSim: Can the LapSim virtual reality simulator distinguish between novices and experts?

Background Virtual reality simulators may be invaluable in training and assessing future endoscopic surgeons. The purpose of this study was to investigate if the results of a training session reflect the actual skill of the trainee who is being assessed and thereby establish construct validity for the LapSim virtual reality simulator (Surgical Science Ltd., Gothenburg, Sweden). Methods Forty-eight subjects were assigned to one of three groups: 16 novices (0 endoscopic procedures), 16 surgical residents in training (>10 but <100 endoscopic procedures), and 16 experienced endoscopic surgeons (>100 endoscopic procedures). Performance was measured by a relative scoring system that combines single parameters measured by the computer. Results The higher the level of endoscopic experience of a participant, the higher the score. Experienced surgeons and surgical residents in training showed statistically significant higher scores than novices for both overall score and efficiency, speed, and precision parameters. Conclusions Our results show that performance of the various tasks on the simulator corresponds to the respective level of endoscopic experience in our research population. This study demonstrates construct validity for the LapSim virtual reality simulator. It thus measures relevant skills and can be integrated in an endoscopic training and assessment program.     

Preliminary validation of the Simulap(®) physical simulator and its assessment system for laparoscopic surgery

IntroductionOur aim is to assess the face and content validities of the physical simulator Simulap^®, as well as the construct validity of its assessment method.Material and methodsFive novice surgeons (G1) and five experts (G2) performed seven basic tasks and one suturing exercise on Simulap^®, which were assessed through an exam based on mistakes and performance time. Face and content validations were carried out by novice surgeons and expert surgeons, respectively. Both validations consisted of a questionnaire graded on a five-point scale about the Simulap^® and its tasks. Construct validity of the assessment system was determined by comparing the scores of both groups.ResultsSurgeons rated the Simulap^® simulator and its training program positively, obtaining an average score of 4 ± 1.1 for G1 and of 4.9 ± 0.6 for G2. G2 considered training on Simulap^® very useful for the training of residents and surgeons, obtaining a maximum score of 5. G2 outperformed G1 in all task scores, with statistically significant differences in the eye-hand coordination (G1: 52.2 ± 6.7 vs. G2: 39.6 ± 6.5; P=.027), dissection (G1: 301.8 ± 100.2 vs. G2: 150.8 ± 66.7; P=.028) and suturing exercises (G1: 258.5 ± 87.0 vs. G2: 108.4 ± 20.2; P=.009).ConclusionsThe assessment method for Simulap^® is able to distinguish different levels of experience in laparoscopic surgery. Furthermore, this simulator showed a great acceptance by surgeons for the learning of basic skills.     

An overview of laparoscopic colorectal surgery

<正> Laparoscopic skills has been widely applied in colorectal surgery.The definition,indications and contraindications, the oncologic principles, port side recurrence, and the newer advances are reported in this article.     

Construct validation of a 3D printed neonatal thoracoscopic simulator: Can it measure expertise?

Backgroundacquiring technical expertise for neonatal thoracoscopy is challenging. To address this, we designed a fully synthetic thoracoscopic simulator for which we established its construct validity.Methodsthree thoracoscopic tasks were assessed: ring transfer, needle pass and incision of a blind upper esophageal pouch (EA cut). Participants watched instructional videos with accompanying written instructions for each task before having their attempt video recorded. All tasks were marked by three blinded pediatric surgeons using a modified Objective Structured Assessment of Technical Skills (OSATS). Scores were assessed using appropriate statistical analysis and inter-rater reliability was analyzed by interclass correlation coefficient (ICC).Results23 participants completed the ring transfer and needle pass and 21 the EA cut: 5 experts (consultant surgeons), 5 intermediate (registrars on a training program) and 13 novices (medical students, house surgeons or non-training registrars). All three tasks distinguished between novice and intermediate/expert (ring transfer p = 0.00001, needle pass p = 0.0004 and EA cut p = 0.0014, respectively). Interrater reliability was good for ring transfer and needle pass but poor for EA cut.Conclusionthe tasks distinguished between novice and intermediate/expert but not between expert and intermediate. In needle pass and EA cut, there was a trend for the experts to score higher than intermediate participants. Ring transfer and needle pass tasks achieved construct validity, had good interrater reliability and were found to be useful in assessing a novice surgeon's progression towards the intermediate level. Distinguishing between intermediate and expert may require assessment of more complex tasks such as intracorporeal suturing and tying.Level of evidenceII     

Preconditioning in laparoscopic surgery—results of a virtual reality pilot study

Background

This prospective study investigated the effect of preconditioning in laparoscopic cholecystectomy (LC) and appendectomy (LA) based on pre- and postoperative virtual reality laparoscopy (VRL) performances, with specific regard to the impact of different motor skills, types of surgery and levels of experience.

Study design

Forty laparoscopic procedures (28 LC and 12 LA) were performed by 13 residents in the operating room. Participants completed a defined set of tasks on the VRL simulator directly prior to and after the operation: one preparational task (PT), a virtual procedural task with emphasis on fine preparation (VPT) and a navigational manoeuvre for instrument coordination (ICT). VRL performances were evaluated based on the assessed items of the simulator.

Results

Overall analysis of the surgeons’ performance demonstrated better postoperative results for PT and VPT in 28 and 26 cases (p?=?0.001 and p?=?0.034), respectively. No significant difference was found for ICT (p?=?0.638). Less-experienced residents had better postoperative results for PT and VPT (p?=?0.009 and p?=?0.041), whereas more-experienced surgeons had better postoperative results for PT only (p?=?0.030). LC resulted in better postoperative performance for PT (p?=?0.007). LA improved performance for PT and VPT (p?=?0.034 and p?=?0.006, respectively). Comparisons of surgeon’s experience demonstrated a significant advantage for more-experienced surgeons in ICT (p?=?0.033), while type of surgery showed an advantage for LA in VPT (p?=?0.022).

Conclusion

There is a preconditioning effect in laparoscopic surgery. The differing results related to LC and LA and the experience levels of surgeons suggest that differentiated warm-up strategies are required.     

Wound dressings for day surgery — a comparison of a conventional dressing (Mepore) with hydrocolloid (Granuflex®)

An extra thin hydrocolloid wound dressing (Granuflex®) was compared to a conventional dry dressing (Mepore) after intermediate and minor day surgical procedures. There was no difference between the two in dressing change frequency or outcome for hernia and varicose vein surgery. Minor surgery patients had significantly less dressing changes, and more patients in both classes were able to bath without disturbing the dressing when Granuflex was used. The hydrocolloid is significantly more expensive than the conventional dressing, but its other advantages may balance this in the day surgery context.     

Hybrid minimally invasive surgery—a bridge between laparoscopic and translumenal surgery

Background The peroral transluminal approach to the peritoneal cavity appears safe, feasible, and may further reduce the invasiveness of surgery. However, flexible endoscopes have multiple limitations inside the peritoneal cavity, which can potentially be overcome by blending the use of both a laparoscope and a flexible upper endoscope—a hybrid approach. The goal of the present study was to evaluate a hybrid minimally invasive technique for cholecystectomy in a porcine model. Methods Hybrid cholecystectomies were performed in acute experiments on 50-kg pigs under general anesthesia. Pneumoperitoneum was created with a Veress needle, and a laparoscopic 10-mm port was inserted. Under laparoscopic observation, the gastric wall incision was done with an endoscopic needle-knife and sphincterotome, and the upper endoscope was advanced into the peritoneal cavity. A laparoscopic 10-mm port was inserted into the right upper quadrant of the abdomen for gallbladder traction to facilitate exposure of the cystic duct and artery. Via the biopsy channel of the flexible endoscope, and using a knife with an isolated tip, a needle knife, and clips, both the cystic duct and artery were identified, clipped, and transected. The gallbladder itself was then dissected and retracted through the mouth, and the gastric wall incision was closed with endoscopic clips. Results Five hybrid cholecystectomies were performed without complications. The laparoscopic port enabled a stable pneumoperitoneum, good traction and counter-traction, and improved spatial orientation and visualization. Necropsy did not reveal any intraperitoneal complications. Conclusions The hybrid approach increases safety of initial gastric puncture and gastric wall incision, improves orientation and navigation of the flexible endoscope inside the peritoneal cavity, simplifies peroral transgastric cholecystectomy, and could be used to decrease invasiveness of laparoscopic surgery and to facilitate development and clinical introduction of transgastric endoscopic procedures. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. This work was presented in part at SAGES Annual Meeting, Dallas, Texas, April 2006     

Does laparoscopic surgery have a role in the treatment of gallbladder cancer?

Background/Purpose: This study was conducted to evaluate the role of laparoscopic surgery in the treatment of gallbladder cancer. Methods: A retrospective study was performed on 31 patients with a postoperative diagnosis of gallbladder cancer. The laparoscopic approach was initially applied to all of them. Results: Ten patients had a pT1a cancer, and all underwent laparoscopic cholecystectomy without recurrence. Nine patients had pT1b lesions, and three had to be converted to an open operation. There were two recurrences. In one of the converted patients the cystic node was invaded. Seven patients had a pT2 lesion, and in four of them the operation was converted to an open procedure. Recurrences were noted in three patients. In two patients with pT3 cancer, the opera-tions were converted; both cancers recurred. Only diagnostic laparoscopy or a palliative laparoscopic procedure was performed for pT4 cancers. The median follow-up time was 17.0 months. The 5-years survival rate was 100% for patients with stage pT1a, 100% for pT1b, and 68% for pT2 lesions. Conclusions: We suggest that when a polypoid lesion of the gallbladder is found on preoperative evaluation, laparoscopic surgery may be attempted initially. During the procedure it is important to open all specimens when a polypoid lesion is present and perform a frozen section biopsy. When a pT1a lesion is found, laparoscopic cholecystectomy is sufficient; however, when a pT1b or more advanced lesion is found, the operation might be converted to a radical cholecystectomy. Received: July 2, 2002 / Accepted: July 2, 2002 Offprint requests to: E.K. Kim     

Training in laparoscopic colorectal surgery �C experience of training in a specialist unit

INTRODUCTION

Laparoscopic colorectal surgery, although technically demanding, is an increasingly desirable skill for coloproc-tologists. We believe that trainees with adequate supervision from an experienced trainer may perform these procedures safely with good outcome.

PATIENTS AND METHODS

Surgical logbooks of two senior trainees were reviewed over a 2-year period. A case note analysis was then undertaken. Patient data were recorded with regards to age, sex, operation type, American Society of Anesthesia (ASA) grade, conversion, length of hospital stay and complications. Lymph node yield, resection margins and grade of total mesorec-tal excision were recorded in oncological procedures.

RESULTS

Over the 2-year period, trainees were involved in 140 resections (age range, 23-88 years; ASA grades I-III). Seventy patients were male. Trainees were first assistant in at least 20 cases prior to undertaking the procedures themselves. Trainees performed a total of 71 operations. Median hospital stay was 7 days (range, 2-48 days). There were three conversions. Anastomotic leaks developed in two patients, one requiring a laparotomy. One patient developed small bowel obstruction secondary to a port site hernia, which was repaired laparoscopically. There was one postoperative death. All oncological resection margins were clear with adequate lymphadenectomies. All total mesorectal excisions were Quirke grade III.

CONCLUSIONS

Adequately trained and supervised trainees may perform major colorectal resections without compromising outcome.     

Management of pancreatic pseudocyst in the era of laparoscopic surgery – Experience from a tertiary centre

Background In the era of minimally invasive surgery, laparoscopy has a great role to play in the management of pseudocyst of pancreas. We present our surgical experience over the past 12 years (May 1994 to April 2006) in the management of pancreatic pseudocysts. Materials and Methods The total number of cases was 108, with 76 male and 32 female patients. Age ranged from 18 to 70 years. Duration of symptoms ranged from 45 days to 7 months. Fifty-nine patients presented with pain abdomen. Sixty-one patients had co-morbid illness. Ten patients had abdominal mass on clinical examination. Predisposing factors were gallstones in 58 cases, alcohol in 20 cases, trauma in eight cases and post-pancreatectomy in one case. In 21 cases there are no predisposing factors. Results All the cases were successfully operated without any significant intraoperative complication. Laparoscopic cystogastrostomy was done in 90 cases (83.4%), laparoscopic cystojejunostomy in eight cases (7.4%), open cystogastrostomy in two cases (1.8%), and laparoscopic external drainage in eight cases (7.4%). Laparoscopic cholecystectomy was done in 47 cases along with the drainage procedure. The mean operating time was 95 minutes. Mean blood loss was 69 ml. Mean hospital stay was 5.6 days. Percutaneous tube drain to assist decompression of the cyst was kept in all the laparoscopic cystojejunostomy (LCJ) group. Two patients were re-operated for bleeding and gastric outlet obstruction. We had no mortality in the postoperative period. With mean follow up of 54 months (range 3–145 months); only one patient who underwent laparoscopic cystogastrostomy (LCG) earlier in this series had recurrence due to inadequate stoma size. This patient later underwent OCG Conclusion Laparoscopy has a significant role to play in the surgical management of pseudocysts with excellent outcome. It offers all the benefits of minimally invasive surgery to the patients.     

Limitations of haptic feedback devices on construct validity of the LapSim® virtual reality simulator

Background

Surgeons performing laparoscopy need a high degree of psychomotor skills, which can be trained and assessed on virtual reality (VR) simulators. VR simulators simulate the surgical environment and assess psychomotor skills according to predefined parameters. This study aimed to validate a proficiency-based training setup that consisted of two tasks with predefined threshold values and handles with haptic feedback on the LapSim^® VR simulator. The two tasks have been found to have construct validity in previous studies using handles without haptic feedback.

Methods

The participants were divided into three groups: novices (0–50 laparoscopic procedures), intermediates (51–300 laparoscopic procedures), and experts (more than 300 procedures). It was assumed that psychomotor skills increase with experience. All participants conducted the tasks lifting and grasping and fine dissection 20 times each. Validity of the training setup was investigated by comparing the number of times each participant passed a predefined threshold level for a set of 19 parameters.

Results

Construct validity was established for one parameter; “misses on right side” on the lifting and grasping task, whereas the other 18 parameters did not show construct validity.

Conclusion

The setup employed in this study failed to establish construct validity for more than one parameter. This indicates that the simulation of haptic feedback influences the training performance on laparoscopic simulators and is an important part of validating a training setup. A haptic device should generate haptic sensations in a realistic manner, without introducing frictional forces that are not inherent to laparoscopy.