Validation of computer-based training in ureterorenoscopy

Semirigid ureteroscopy for ureteral stones: a multivariate analysis of unfavorable results

PURPOSE

We determined the factors predicting unfavorable results of semirigid ureteroscopy for ureteral calculi.

MATERIALS AND METHODS

We reviewed the computerized files of 841 patients who underwent a total of 908 ureteroscopic procedures for ureteral stones from January 2003 through December 2006. A semirigid 6/7.5Fr ureteroscope was used in pediatric patients and an 8/10Fr or 8.5/11.5Fr ureteroscope was used in adults. Patients with favorable results were those who became stone-free after a single ureteroscopic procedure without any complications. They were compared with patients who had unfavorable results using univariate (chi-square and t tests) and multivariate (logistic regression) statistical tests to identify risk factors for unfavorable results.

RESULTS

The study included 567 males and 274 females with a mean age of 48.5 years (range 2 to 81). The complication rate was 6.7% (61 procedures). The stone-free rate after a single ureteroscopic intervention was 87% (791 procedures). Favorable results were documented in 751 procedures (82.7%). Significant factors for unfavorable results were proximal ureteral stones, ureteroscopy done by surgeons other than experienced endourologists, stone impaction and stone width (relative risk 4, 2.5, 1.8 and 1.2, respectively).

CONCLUSIONS

Semirigid ureteroscopy is a safe and highly effective treatment modality for ureteral stones.

Update on training models in endourology: a qualitative systematic review of the literature between January 1980 and April 2008

CONTEXT

Interest in the use of simulators in urological skills training is on the increase. To ensure effective implementation of training models, an overview of the nature and validity of the available models is of the essence.

OBJECTIVE

To obtain an overview of training models and their validity by performing a qualitative systematic review of the literature.

EVIDENCE ACQUISITION

Studies were identified through searches of PubMed, the Cochrane Library, and Web of Science between January 1980 and April 2008 using two search strategies: "urology and (training or simulat or model)" and combinations of these terms with "prostate," "kidney," "bladder," or "ureter." Studies were included if they (1) described one or more training models, and/or (2) examined the validity of training models. Studies in undergraduate education and of training models for physical examination were excluded. Validation studies were scored according to Kirkpatrick and Oxford Centre for Evidence-Based Medicine (OCEBM) levels of evidence.

EVIDENCE SYNTHESIS

Forty-five articles (out of the initial list of 4753 retrieved articles, 0.9%) were included, describing 30 types of training models and 54 validation studies. The largest number of models has been described for ureterorenoscopy (nine types). Only three randomised controlled trials (RCTs), receiving a 1b OCEBM level of evidence score, were found. Studies investigating the impact of simulator training on performance in patients (criterion B validity) were scarce. The number of participants in experimental studies ranged from 7 to 136.

CONCLUSIONS

Due to growing interest in training models in urology, it is increasingly urgent to determine which of these models are most valuable for postgraduate training. Because the validation studies published so far are few in number, have low evidence levels, and are composed of only a few RCTs, it is important that more randomised controlled validation studies including larger numbers of participants are performed.

Holmium laser lithotripsy for ureteral calculi: predictive factors for complications and success

PURPOSE

To define possible predictive factors for success and complications for ureteroscopic holmium laser lithotripsy procedures.

PATIENTS AND METHODS

All 105 ureteroscopic holmium laser lithotripsy procedures performed between 1996 and 2005 were analyzed. Data recorded were sex, age, stone size, stone location, complications, success rate (stone-free rate after 3 months), operative time, and surgeon experience for this procedure. For further analysis, surgeon experience was divided into four groups based on the number of procedures performed. Multivariate analysis was used to define possible predictive factors for complications and successful procedures.

RESULTS

Total success rate was 84.8%. Complications were present in 13 patients (12.4%). Success rate was significantly (P = 0.03) related to surgeon experience, with 92.9% success in the most experienced group and 50% in the least experienced group. Furthermore, significantly more complications occurred with decreased experience (P = 0.03): complication rate was 4.2% in the highest experience group and 41.7% in the least experienced group. In our series, sex, stone location, size, and age did not significantly influence complication and success rates.

CONCLUSION

Surgeon experience is a predictive factor for complications and success for ureteroscopic holmium laser lithotripsy for ureteric calculi. Experienced surgeons have fewer complications, and the success rate is higher. Sex, stone location, size, and age were not significantly related to complication or success rates.

VR to OR: a review of the evidence that virtual reality simulation improves operating room performance

The use of virtual reality (VR) simulation to train surgeons has been supported by a body of experimental data derived from randomized trials of VR simulation training versus no such training. These investigations have focused on the use of VR devices to train surgeons in laparoscopic and flexible endoscopic skills, and the studies have generally demonstrated that skills acquired through courses of training in VR transfer to the clinical or animal laboratory setting, where assessments of various types have been used to measure performance. These studies, as well as the study model that describes them, and the future of randomized trials of this type are reviewed.

Training in percutaneous nephrolithotomy--a critical review

AIM

To study factors influencing training and maintaining skills in performing percutaneous nephrolithotomy (PCNL).

METHODS

We matched key words, throughout Medline, MeSH, and Cochrane databases including: renal stone, percutaneous, nephrostomy, endourology, educational, training, learning curve, expertise, skill, residency, practice, survey, simulator, and robotics. For this topic we defined, if possible, levels of evidence based on International Consultation on Urological Diseases (ICUD) and World Health Organization recommendations.

RESULTS

Obtaining renal access is one of the most important factors in training for PCNL. A resident has to perform about 24 PCNL procedures to obtain a good proficiency during the residence period. Competence at performing PCNL is reached after 60 cases and excellence is obtained at >100 cases. Stone centers providing all the endoscopic treatment options seem to provide the best conditions to ensure a sufficient volume of patients recruited. Virtual reality simulators may have a potential in training for PCNL. To maintain one's expertise, participation in continuing educational programs is recommended.

CONCLUSION

PCNL is currently the most complicated stone surgery technique to teach. The steep learning curve is mainly related to obtaining renal access. The traditional method of acquiring surgical skills is by apprenticeship in the absence of validated virtual simulators. Given the complexity of the treatment of renal stones, one may consider a centralized renal stone treatment in dedicated stone centers.

A Biological Model to Teach Percutaneous Nephrolithotomy Technique with Ultrasound- and Fluoroscopy-Guided Access

PURPOSE

To develop a training model for simulated percutaneous nephrolithotomy (PCNL) under ultrasound and fluoroscopy-guided access.

MATERIALS AND METHODS

The laboratory model for PCNL described by Hammond and associates (J Urol 2004;172:1950-1952) was modified. We used an ex-vivo perfused porcine kidney (freshly removed after commercial slaughtering), a chicken carcass (supermarket), as well as the standard equipment for PCNL. For imaging, ultrasound (7.5 MHz) and a fluoroscopy unit are necessary. Artificial stone material is implanted in the renal pelvis. The ureter is cannulated for retrograde pyelography and the renal artery and vein for continuous perfusion. The perfused kidney surrounded by ultrasound gel is placed in the eviscerated chicken carcass.

RESULTS

The model is low cost and simple to set up, with a preparation time of about 15 minutes. The equipment used in clinical practice can be employed for renal access, tract dilation, nephroscopy, stone disintegration, and stone removal. Imaging is feasible under fluoroscopic and ultrasound guidance.

CONCLUSIONS

This biological training model simulates realistically the clinical procedure of PCNL under ultrasound and fluoroscopic guidance. Teaching and skill acquisition are practicable.

Ureteroscopy and Cystoscopy Simulation in Urology

Transformations of many aspects of surgery have provided a potentially fertile ground for the implementation of surgical simulators in the medical mainstream. The expansion of minimally invasive diagnostic and therapeutic modalities, increasing healthcare demands, fiscal constraints, and sensitivity to medicolegal considerations limit resident instruction and practical experience in the operating room. Furthermore, the need for objective, structured assessments of surgical residents during training and the requirement for physicians to gain and maintain certification demand that innovative solutions be sought. Surgical simulators are poised to deliver broad-based training experiences to trainees of all levels. In urology, simulation has been centered on endourologic procedures, namely ureteroscopy and cystoscopy. In this paper, various models of simulation developed for ureteroscopy and cystoscopy in urology are reviewed, with a brief description of each model, its benefits and disadvantages, and current research surrounding each simulation model.

[Use of a virtual immersion computer simulator as a model for basic training in laparoscopic urology]

BACKGROUND

to date, it has not been defined the best method for teaching urologic laparoscopy, however it is well recognized that it involves a steep learning curve.

METHODS

A course of Laparoscopic Urology was done in our Institute. The program included skill practices in a virtual immersion simulator which evaluated, the score and time to complete each activity. This was done in a group of residents with previous experience with this virtual simulator (group 1) and another group of residents with no experience (group 2). Four different basic tasks were performed in the virtual simulator, which included: coordination, cutting, clip application and performing a simple suture.

RESULTS

When we compared the scores between both groups the mean scores for each task were superior in group 1 compared to the group 2, with no statistically significant difference, however when we compared the time to complete each task, it was shorter in group 1 compared to group 2 with a statistically significant difference.

CONCLUSIONS

The performance of residents without experience in a virtual simulator was similar to that of previously trained residents, however it takes less time to complete each task as the resident gains experience in these simulators. The use of virtual simulators for laparoscopy training are useful when learning basic techniques allowing the surgeon to improve hand dexterity and coordination in laparoscopic surgery.

Simulation training in video-assisted urologic surgery

The current system of surgical education is facing many challenges in terms of time efficiency, costs, and patient safety. Training using simulation is an emerging area, mostly based on the experience of other high-risk professions like aviation. The goal of simulation-based training in surgery is to develop not only technical but team skills. This learning environment is stress-free and safe, allows standardization and tailoring of training, and also objectively evaluate performances. The development of simulation training is straightforward in endourology, since these procedures are video-assisted and the low degree of freedom of the instruments is easily replicated. On the other hand, these interventions necessitate a long learning curve, training in the operative room is especially costly and risky. Many models are already in use or under development in all fields of video-assisted urologic surgery: ureteroscopy, percutaneous surgery, transurethral resection of the prostate, and laparoscopy. Although bench models are essential, simulation increasingly benefits from the achievements and development of computer technology. Still in its infancy, virtual reality simulation will certainly belong to tomorrow's teaching tools.

Medical devices used for ureteroscopy for renal calculi

Urinary stone disease is a problem as old as human civilization. In this article, a brief history of stone disease and the current status of urinary stone disease treatment will be discussed. This review will focus primarily on the newest technology and devices associated with flexible ureteropyeloscopy for the treatment of upper tract urinary stones. In addition to defining the cutting-edge technology that is newly available, this review will glimpse at what technologic advances are expected in the near future. Reference articles that do a good job of defining the current state of flexible ureteropyeloscopy technology and urinary stone disease treatment will be highlighted, along with a reiteration of the major points of the article.