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A G Gallagher

Publications and source records attributed to A G Gallagher.

At least 19 recordsLinked to original sources
PubMed2005

Correlation between perceptual, visuo-spatial, and psychomotor aptitude to duration of training required to reach performance goals on the MIST-VR surgical simulator.

Given the dynamic nature of modern surgical education, determining factors that may improve the efficiency of laparoscopic training is warranted. The objective of this study was to analyze whether perceptual, visuo-spatial, or psychomotor aptitude are related to the amount of training required to reach specific performance-based goals on a virtual reality surgical simulator. Sixteen MS4 medical students participated in an elective skills course intended to train laparoscopic skills. All were tested for perceptual, visuo-spatial, and psychomotor aptitude using previously validated psychological tests. Training involved as many instructor-guided 1-hour sessions as needed to reach performance goals on a custom designed MIST-VR manipulation-diathermy task (Mentice AB, Gothenberg, Sweden). Thirteen subjects reached performance goals by the end of the course. Two were excluded from analysis due to previous experience with the MIST-VR (total n = 11). Perceptual ability (r = -0.76, P = 0.007) and psychomotor skills (r = 0.62, P = 0.04) significantly correlated with the number of trials required. Visuo-spatial ability did not significantly correlate with training duration. The number of trials required to train subjects to performance goals on the MIST-VR manipulation diathermy task is significantly related to perceptual and psychomotor aptitude.

Adult↗
PubMed2004

Analysis of errors in laparoscopic surgical procedures.

BACKGROUND: The determination of laparoscopic surgeon ability is essential to training error avoidance. The present study describes a practical method of surgical error analysis. METHODS: After review of practice videotapes of the excisional phase of laparoscopic cholecystectomy, consensus on the identification of eight errors was achieved. Interrater agreement at the end of this phase was 84-96%. Fourteen study videotapes of gallbladder excision were then observed independently by expert reviewers blinded to surgical team identity. Procedures were assessed using a scoring matrix of 1-min segments with each error reported each minute. RESULTS: Interrater agreement was 84-100% for all error categories. CONCLUSIONS: The present study demonstrates that excellent interrater agreement of procedural errors can be achieved by carefully defining and training recognition of targeted events. Extension of this simple and reliable analysis tool to other procedures should be feasible to define behaviors leading to adverse clinical outcomes.

Burns↗
PubMed2004

Discriminative validity of the Minimally Invasive Surgical Trainer in Virtual Reality (MIST-VR) using criteria levels based on expert performance.

BACKGROUND: Increasing constraints on the time and resources needed to train surgeons have led to a new emphasis on finding innovative ways to teach surgical skills outside the operating room. Virtual reality training has been proposed as a method to both instruct surgical students and evaluate the psychomotor components of minimally invasive surgery ex vivo. METHODS: The performance of 100 laparoscopic novices was compared to that of 12 experienced (>50 minimally invasive procedures) and 12 inexperienced (<10 minimally invasive procedures) laparoscopic surgeons. The values of the experienced surgeons' performance were used as benchmark comparators (or criterion measures). Each subject completed six tasks on the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR) three times. The outcome measures were time to complete the task, number of errors, economy of instrument movement, and economy of diathermy. RESULTS: After three trials, the mean performance of the medical students approached that of the experienced surgeons. However, 7-27% of the scores of the students fell more than two SD below the mean scores of the experienced surgeons (the criterion level). CONCLUSIONS: The MIST-VR system is capable of evaluating the psychomotor skills necessary in laparoscopic surgery and discriminating between experts and novices. Furthermore, although some novices improved their skills quickly, a subset had difficulty acquiring the psychomotor skills. The MIST-VR may be useful in identifying that subset of novices.

Adult↗
PubMed2004

Identifying and reducing errors with surgical simulation.

The major determinant of a patient's safety and outcome is the skill and judgment of the surgeon. While knowledge base and decision processing are evaluated during residency, technical skills-which are at the core of the profession-are not evaluated. Innovative state of the art simulation devices that train both surgical tasks and skills, without risk to patients, should allow for the detection and analysis of errors and "near misses". Studies have validated the use of a sophisticated endoscopic sinus surgery simulator (ES3) for training residents on a procedural basis. Assessments are proceeding as to whether the integration of a comprehensive ES3 training programme into the residency curriculum will have long term effects on surgical performance and patient outcomes. Using various otolaryngology residencies, subjects are exposed to mentored training on the ES3 as well as to minimally invasive trainers such as the MIST-VR. Technical errors are identified and quantified on the simulator and intraoperatively. Through a web based database, individual performance can be compared against a national standard. An upgraded version of the ES3 will be developed which will support patient specific anatomical models. This advance will allow study of the effects of simulated rehearsal of patient specific procedures (mission rehearsal) on patient outcomes and surgical errors during the actual procedure. The information gained from these studies will help usher in the next generation of surgical simulators that are anticipated to have significant impact on patient safety.

Computer-Assisted Instruction↗
PubMed2003

PicSOr: an objective test of perceptual skill that predicts laparoscopic technical skill in three initial studies of laparoscopic performance.

BACKGROUND: Laparoscopic surgery requires surgeons to infer the shape of 3-D structures, such as the internal organs of patients, from 2-D displays on a video monitor. Recent evidence indicates that the issue is not resolved by the use of contemporary 3-D camera systems. It is therefore crucial to find ways of measuring differences in aptitude for recovering 3-D structure from 2-D images, and assessing its impact on performance. Our aim was to test empirically for a relationship between laparoscopic ability and the perceptual skill of recovering information about 3-D structures from 2-D monitor displays. METHODS: Participants in three studies completed a simulated laparoscopic cutting task as well as the Pictorial Surface Orientation (PicSOr)3 Test. In studies 1 (n = 48) and 2 (n = 32) both groups were laparoscopic novices, and in study 3 (n = 34) 18 of the participants were experienced laparoscopic surgeons. FINDINGS: All three studies showed that PicSOr consistently predicted the laparoscopic performance of participants on the laparoscopic cutting task (study 1, r = 0.5, p < 0.0003; study 2, r = 0.5, p < 0.004; and study 3, r = 0.42, p = 0.017). Furthermore, it was also a significant predictor of laparoscopic surgeons' performance (r = 0.54, p = 0.047). INTERPRETATIONS: This is the first objective perceptual psychometric test to reliably predict laparoscopic technical skills. PicSOr provides a tool for assessing which trainees have the potential to learn minimal access surgery.

Adult↗
PubMed2002

Virtual reality as a metric for the assessment of laparoscopic psychomotor skills. Learning curves and reliability measures.

BACKGROUND: The objective assessment of the psychomotor skills of surgeons is now a priority; however, this is a difficult task because of measurement difficulties associated with the assessment of surgery in vivo. In this study, virtual reality (VR) was used to overcome these problems. METHODS: Twelve experienced (>50 minimal-access procedures), 12 inexperienced laparoscopic surgeons (<10 minimal-access procedures), and 12 laparoscopic novices participated in the study. Each subject completed 10 trials on the Minimally Invasive Surgical Trainer; Virtual Reality (MIST VR). RESULTS: Experienced laparoscopic surgeons performed the tasks significantly (p < 0.01) faster, with less error, more economy in the movement of instruments and the use of diathermy, and with greater consistency in performance. The standardized coefficient alpha for performance measures ranged from a = 0.89 to 0.98, showing high internal measurement consistency. Test-retest reliability ranged from r = 0.96 to r = 0.5. CONCLUSION: VR is a useful tool for evaluating the psychomotor skills needed to perform laparoscopic surgery.

Adult↗
PubMed2001

Evaluation of structured and quantitative training methods for teaching intracorporeal knot tying.

BACKGROUND: We evaluated the effectiveness of five training methods-four structured and one unstructured-for teaching intracorporeal knot tying. METHODS: Forty-three graduate students without prior laparoscopic experience were randomly assigned to one of five training groups, and their performance in 10 intracorporeal knot tying trials was evaluated, using time to complete a knot as the outcome measure. RESULTS: The average knot tying times for the four structured groups were significantly faster than the unstructured group (p < 0.0001). Among the four structured groups, the minimally invasive surgical trainer-virtually reality (MIST-VR) and the box trainer drills showed the most rapid improvements. The MIST-VR improved average suturing time from trial one to trial two (P = 0.05), the box trainer drills group improved from trial one to trial four (P = 0.01), and the other two groups showed slower improvements. Statistically significant correlations were observed between scores on MIST-VR tasks and average knottying times (R > 0.7, p < 0.05). CONCLUSION: Structured training can be useful for the development of laparoscopic skills. MIST-VR is a valuable part of this training, particularly in the objective evaluation of performance.

Adult↗
PubMed2001

Objective psychomotor skills assessment of experienced, junior, and novice laparoscopists with virtual reality.

Objective assessment of psychomotor skills in surgery is now a priority; however, this assessment is difficult to achieve because of measurement difficulties associated with the reliability and validity of assessing surgical skills in vivo and in the laboratory. In this study virtual reality (VR) was used to overcome these problems in the objective psychomotor assessment of senior, junior, and novice laparoscopists. Twelve experienced laparoscopic surgeons (performed >50 Minimal Access Surgery (MAS) procedures), 12 inexperienced laparoscopic surgeons (<10 MAS procedures), and 12 laparoscopic novices (no MAS procedures) participated in the study. Each subject completed all six tasks of the Minimally Invasive Surgical Trainer; Virtual Reality (MIST VR). In comparison to the other groups, experienced laparoscopic surgeons performed the tasks significantly (p < 0.01) faster, had a lower error rate, were more economic in their movement of surgical instruments and in the use of diathermy. As a group they also showed greater consistency in their performance. MIST VR distinguished between the three groups of laparoscopists. VR provides a useful objective assessment tool for evaluating psychomotor skills for laparoscopic surgery.

Adult↗
PubMed2001

Virtual reality training leads to faster adaptation to the novel psychomotor restrictions encountered by laparoscopic surgeons.

BACKGROUND: The fulcrum effect of the body wall on instrument handling poses a major obstacle to the mastery of instrument coordination for junior laparoscopic surgeons. This study evaluated three types of laparoscopic simulator training to assess their ability to promote the user's adaptation to the fulcrum effect. METHODS: Thirty-two participants with no previous experience in laparoscopic surgery were randomly assigned to one of four groups representing different training conditions. One group was assigned to use a virtual reality simulator (MIST VR); two others were given a laparoscopic Z or U maze-tracking task. The control group received no training. Subjects were asked to perform a 2-min laparoscopic cutting task under normal laparoscopic imaging conditions first before and then after training. RESULTS: In the test trial, subjects who trained on MIST VR made significantly more correct incisions (p < 0.0001) and fewer incorrect incisions (p < 0.0001). CONCLUSION: Training on a virtual reality simulator such as MIST VR helps laparoscopic novices adapt to the fulcrum effect faster.

Clinical Competence↗
PubMed2000

A comparison between randomly alternating imaging, normal laparoscopic imaging, and virtual reality training in laparoscopic psychomotor skill acquisition.

OBJECTIVES: To evaluate virtual reality as a laparoscopic training device in helping surgeons to automate to the "fulcrum effect" by comparing it to time-matched training programs using randomly alternating images (ie, y-axis inverted and normal laparoscopic) and normal laparoscopic viewing conditions. METHODS: Twenty-four participants (16 females and 8 males), were randomly assigned to minimally invasive surgery virtual reality (MIST VR), randomly alternating (between y-axis inverted and normal laparoscopic images), and normal laparoscopic imaging condition. Participants were requested to perform a 2-minute laparoscopic cutting task before and after training. RESULTS: In the test trial participants who trained on the MIST VR performed significantly better than those in the normal laparoscopic and randomly alternating imaging conditions. CONCLUSION: The results show that virtual reality training may provide faster skill acquisition with particular reference to automation of the fulcrum effect. MIST VR provides a new way of training laparoscopic psychomotor surgical skills.

Adult↗
PubMed2000

Randomly alternating image presentation during laparoscopic training leads to faster automation to the "fulcrum effect".

BACKGROUND AND STUDY AIMS: The aim of this study was to evaluate four training programmes intended to help laparoscopic surgeons automate to the "fulcrum effect". METHODS: A total of 32 participants (16 men, 16 women), were randomly assigned to one of four different image-viewing conditions: full binocular, y-axis inverted, normal laparoscopic and randomly alternating (between y-axis-inverted and normal laparoscopic). The subjects were requested to perform 10 trials of a simple laparoscopic cutting task, each lasting 2 minutes. Each then completed a 2-minute test under normal laparoscopic imaging conditions. RESULTS: In the final test trial, participants who trained under the randomly alternating imaging conditions (y-axis inverted and normal laparoscopic) performed significantly better than those from the other groups. CONCLUSION: Training under a randomly alternating viewing condition helps laparoscopic trainees automate to the "fulcrum effect" faster.

Adolescent↗
PubMed2000

Voluntary euthanasia in Northern Ireland: general practitioners' beliefs, experiences, and actions.

BACKGROUND: There has been much recent interest in the press and among the profession on the subject of euthanasia and physician-assisted suicide. The BMA recently conducted a 'consensus conference' over the internet to collect views on physician-assisted suicide. Any surveys to date have addressed a variety of specialties; however, no recent surveys have looked at general practitioner (GP) attitudes and experiences. AIM: To explore the attitudes of GPs in Northern Ireland towards the issue of patient requests for euthanasia, their nature, and doctors' experiences of such requests. METHOD: An anonymous, confidential postal survey of all (1053) GP principals in Northern Ireland. RESULTS: Seventy per cent of responders believe that passive euthanasia is both morally and ethically acceptable. Fewer (49%) would be prepared to take part in passive euthanasia. However, over 70% of physicians responding consider physician-assisted suicide and voluntary active euthanasia to be wrong. Thirty per cent of responders have received requests from patients for euthanasia in the past five years. One hundred and seven doctors gave information about these requests. Thirty-nine out of 54 patient requests for passive euthanasia had been complied with, as had one of 19 requests for physician-assisted suicide and four out of 38 patient requests for active euthanasia. Doctors perceived the main reasons why patients sought euthanasia was because of fear of loss of dignity and fear of being a burden to others. CONCLUSIONS: While the majority of GPs support passive euthanasia, they, in common with those who approve of assisted suicide and active euthanasia, often express a reluctance to take part in such actions. This may reflect the moral, legal, and emotional dilemmas doctors encounter when facing end-of-life decisions.

Attitude of Health Personnel↗
PubMed1999

Virtual reality training in laparoscopic surgery: a preliminary assessment of minimally invasive surgical trainer virtual reality (MIST VR).

BACKGROUND: The "fulcrum effect" of the body wall on surgical instrument manipulation is a major hurdle for novice endoscopic surgeons. Virtual reality training has not previously been evaluated as a means to overcome this problem. MATERIALS AND METHODS: 16 participants with no experience of endoscopy were required to make multiple defined incisions under laparoscopic laboratory conditions within 2-minute periods. Half of the subjects were randomized to receive initial training on the Minimally Invasive Surgical Trainer, Virtual Reality (MIST VR) computer programme. RESULTS: Participants with MIST VR training made significantly more correct incisions (P = 0.0001) than the control group on test trial 1, and even after extended practice by both groups (P = 0.0001). They were also significantly more likely to actively use both hands to perform the endoscopic evaluation task (P = 0.01). CONCLUSIONS: Virtual reality training represents a potential, viable solution for junior endoscopists, for overcoming the "fulcrum effect", in a replicable, safe learning environment which allows objective and reliable quantification of skill levels by trainers.

Adult↗
PubMed1999

Experienced laparoscopic surgeons are automated to the "fulcrum effect": an ergonomic demonstration.

BACKGROUND AND STUDY AIMS: The inversion of the normal laparoscopic image around the Y-axis has been shown to facilitate the rate of learning of a laparoscopic task in novice subjects. The aim of this study was to investigate the effect of Y-axis image inversion on the performance of experienced laparoscopic surgeons; this had not been previously investigated. METHODS: A total of 16 experienced surgeons,who had already carried out more than 50 operative laparoscopic procedures, and 16 novice participants, who had carried out no procedures, were required to make multiple defined incisions under laparoscopic laboratory conditions within ten 1-minute periods. Participants were randomly allocated to perform the task under either normal or Y-axis inverted imaging conditions (eight experienced surgeons and eight novices in each condition). RESULTS: Y-axis inversion had a significant detrimental effect on the performance of the surgeons, whilst facilitating the performance of novices. The surgeons however, adapted to the inverted condition rapidly, showing a significant improvement in performance over the ten trials. CONCLUSIONS: The Y-axis-inverted image has a detrimental effect on the performance of experienced surgeons, indicating that they have automated to the "fulcrum effect" of the abdominal wall on instrument manipulation. Y-axis-image inversion was found to facilitate significant learning trends, regardless of the participants' level of experience.

Abdomen↗
PubMed1998

An ergonomic analysis of the fulcrum effect in the acquisition of endoscopic skills.

BACKGROUND: The loss of three-dimensional visual depth cues has been thought to be the main hindrance to the acquisition of endoscopic skills. However, the "fulcrum effect" of the abdominal wall on the manipulation of instruments has not to our knowledge been previously investigated. METHODS: Subjects with no experience in endoscopy were required to make multiple defined incisions under laparoscopic laboratory conditions, within ten two-minute periods in the first study and 50 in the second. Eleven subjects operated under normal imaging conditions and 11 with the y-axis inverted. RESULTS: Subjects who operated with the image inverted made significantly more incisions and significantly more correct incisions than those working under normal conditions. This effect persisted over 50 trials. CONCLUSIONS: The fulcrum effect has a major detrimental influence on acquisition of endoscopic skills. Further work is required to investigate the role of image inversion in clinical endoscopic training.

Adult↗