Simulateur pédagogique médical : la phacoémulsification en réalité virtuelle

Virtual reality training for cataract surgery operating performance in ophthalmology trainees

BACKGROUND

Cataract surgery is the most common incisional surgical procedure in ophthalmology and is important in ophthalmic graduate medical education. Although most ophthalmology training programs in the United States (US) include virtual reality (VR) training for cataract surgery, comprehensive reviews that detail the impact of VR training on ophthalmology trainee performance are lacking.

OBJECTIVES

To assess the impact of VR training for cataract surgery on the operating performance of postgraduate ophthalmology trainees, measured by operating time, intraoperative complications, postoperative complications, supervising physician ratings, and VR simulator task ratings.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), Ovid MEDLINE, Embase.com, PubMed, LILACS, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 14 June 2021.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing VR training to any other method of training, including non-VR simulation training (e.g., wet laboratory training), didactics training, or no supplementary training in postgraduate ophthalmology trainees.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology. Primary outcomes were operating times in the operating room and intraoperative complications. Secondary outcomes were operating times in simulated settings, simulator task ratings, and supervising physician ratings, either in the operating room or simulated settings.

MAIN RESULTS

We included six RCTs with a total of 151 postgraduate ophthalmology trainees ranging from 12 to 60 participants in each study. The included studies varied widely in terms of geography: two in the US, and one study each in China, Germany, India, and Morocco. Three studies compared VR training for phacoemulsification cataract surgery on the Eyesi simulator (VRmagic, Mannheim, Germany) with wet laboratory training and two studies compared VR training with no supplementary training. One study compared trainees who received VR training with those who received conventional training for manual small incision cataract surgery on the HelpMeSee simulator (HelpMeSee, New York, NY). Industry financially supported two studies. All studies had at least three domains judged at high or unclear risks of bias. We did not conduct a meta-analysis due to insufficient data (i.e., lack of precision measurements, or studies reported only P values). All evidence was very low-certainty, meaning that any estimates were unreliable. The evidence for the benefits of VR training for trainees was very uncertain for primary outcomes. VR-trained trainees relative to those without supplementary training had shorter operating times (mean difference [MD] -17 minutes, 95% confidence interval [CI] -21.62 to -12.38; 1 study, n = 12; very low-certainty evidence). Results for operating time were inconsistent when comparing VR and wet laboratory training: one study found that VR relative to wet laboratory training was associated with longer operating times (P = 0.038); the other reported that two training groups had similar operating times (P = 0.14). One study reported that VR-trained trainees relative to those without supplementary training had fewer intraoperative complications (P < 0.001); in another study, VR and conventionally trained trainees had similar intraoperative complication rates (MD -8.31, 95% CI -22.78 to 6.16; 1 study, n = 19; very low-certainty evidence). For secondary outcomes, VR training may have similar impact on trainee performance compared to wet laboratory and greater impact compared to no supplementary training, but the evidence was very uncertain. One study reported VR-trained trainees relative to those without supplementary training had significantly reduced operating time in simulated settings (P = 0.0013). Another study reported that VR-trained relative to wet laboratory-trained trainees had shorter operating times in VR settings (MD -1.40 minutes, 95% CI -1.96 to -0.84; 1 study, n = 60) and similar times in wet laboratory settings (MD 0.16 minutes, 95% CI -0.50 to 0.82; 1 study, n = 60). This study also found the VR-trained trainees had higher VR simulator ratings (MD 5.17, 95% CI 0.61 to 9.73; 1 study, n = 60). Results for supervising physician ratings in the operating room were inconsistent: one study reported that VR- and wet laboratory-trained trainees received similar supervising physician ratings for cataract surgery (P = 0.608); another study reported that VR-trained trainees relative to those without supplementary training were less likely to receive poor ratings by supervising physicians for capsulorhexis construction (RR 0.29, 95% CI 0.15 to 0.57). In wet laboratory settings, VR-trained trainees received similar supervising physician ratings compared with wet laboratory-trained trainees (MD -1.50, 95% CI -6.77 to 3.77; n = 60) and higher supervising physician ratings compared with trainees without supplementary training (P < 0.0001). However, the results for all secondary outcomes should be interpreted with caution because of very low-certainty evidence.  AUTHORS' CONCLUSIONS: Current research suggests that VR training may be more effective than no supplementary training in improving trainee performance in the operating room and simulated settings for postgraduate ophthalmology trainees, but the evidence is uncertain. The evidence comparing VR with conventional or wet laboratory training was less consistent.

Surgical Workflow Management Schemata for Cataract Procedures

Objective: Workflow guidance of surgical activities is a challenging task. Because of variations in patient properties and applied surgical techniques, surgical processes have a high variability. The objective of this study was the design and implementation of a surgical workflow management system (SWFMS) that can provide a robust guidance for surgical activities. We investigated how many surgical process models are needed to develop a SWFMS that can guide cataract surgeries robustly.

Methods: We used 100 cases of cataract surgeries and acquired patient-individual surgical process models (iSPMs) from them. Of these, randomized subsets iSPMs were selected as learning sets to create a generic surgical process model (gSPM). These gSPMs were mapped onto workflow nets as work-flow schemata to define the behavior of the SWFMS. Finally, 10 iSPMs from the disjoint set were simulated to validate the workflow schema for the surgical processes. The measurement was the successful guidance of an iSPM.

Results: We demonstrated that a SWFMS with a workflow schema that was generated from a subset of 10 iSPMs is sufficient to guide approximately 65% of all surgical processes in the total set, and that a subset of 50 iSPMs is sufficient to guide approx. 80% of all processes.

Conclusion: We designed a SWFMS that is able to guide surgical activities on a detailed level. The study demonstrated that the high inter-patient variability of surgical processes can be considered by our approach.

Cumulative sum analysis score and phacoemulsification competency learning curve

AIM

To use the cumulative sum analysis score (CUSUM) to construct objectively the learning curve of phacoemulsification competency.

METHODS

Three second-year residents and an experienced consultant were monitored for a series of 70 phacoemulsification cases each and had their series analysed by CUSUM regarding posterior capsule rupture (PCR) and best-corrected visual acuity. The acceptable rate for PCR was <5% (lower limit h) and the unacceptable rate was >10% (upper limit h). The acceptable rate for best-corrected visual acuity worse than 20/40 was <10% (lower limit h) and the unacceptable rate was >20% (upper limit h). The area between lower limit h and upper limit h is called the decision interval.

RESULTS

There was no statistically significant difference in the mean age, sex or cataract grades between groups. The first trainee achieved PCR CUSUM competency at his 22^nd case. His best-corrected visual acuity CUSUM was in the decision interval from his third case and stayed there until the end, never reaching competency. The second trainee achieved PCR CUSUM competency at his 39^th case. He could reach best-corrected visual acuity CUSUM competency at his 22^nd case. The third trainee achieved PCR CUSUM competency at his 41^st case. He reached best-corrected visual acuity CUSUM competency at his 14^th case.

CONCLUSION

The learning curve of competency in phacoemulsification is constructed by CUSUM and in average took 38 cases for each trainee to achieve it.

A virtual training simulator for learning cataract surgery with phacoemulsification

This paper presents the development of a low-cost cataract surgery simulator for trainees to practise phacoemulsification procedures with computer-generated models in virtual environments. It focuses on the training of cornea incision, capsulorrhexis and phaco-sculpting, which are simulated interactively with computationally efficient algorithms developed for tissue deformation, surface cutting and volume sculpting. Intuitive two-handed human-computer interactions are achieved with six degrees-of-freedom haptic devices. Performance of trainees on manual dexterity is recorded with quantifiable metrics. The proposed virtual-reality system has the potential to serve as an alternative training tool to supplement conventional cataract surgery education.