We would like to thank the authors for their comments in response to our article, “Virtual Reality-Based Simulation Training for Ventriculostomy: An Evidence-Based Approach.”1 We would like to point out that the intent of our article was to demonstrate that neurosurgical resident training in ventriculostomy placement can be enhanced through virtual reality-based simulation training. We chose a commercially available simulator, designed by ImmersiveTouch (Chicago, Illinois),2 to provide ventriculostomy training to neurosurgical residents as part of a larger simulation course. We wish to clarify that none of the authors of our article were involved in the development of the simulator.
We are pleased to see that the authors have now developed an iPad application3 to supplement their Web-based surgical ventriculostomy simulator.4 As they describe, there are many components of educating trainees in surgical techniques. Their simulator offers the ability to perform key components of ventriculostomy placement, including selection of an entry point and trajectory of the catheter and selection of depth of catheter placement. Final catheter placement can then be verified by a cutaway image of the brain. Although there is no haptic feedback with this system, and in truth, realistic haptics are a limitation of even the most advanced virtual reality-based simulators at this time, we contend that the most common errors in ventriculostomy placement may be avoided by educating trainees with simulators such as the VCath, described by the authors, and the ImmersiveTouch system, which we used as part of our training course. The technical implementation of a simulator is a necessary component of a successful, validated simulation curriculum. As described in our article, the use of structured instruction and testing is at least equally as important. We were unable to ascertain from their article whether the authors were able to embark on the formal assessment of their simulator as a validated simulation system.4
We concur that validation of surgical simulators is a complex yet essential component of simulation training. We agree that it is important to evaluate educational components and procedural fidelity. In our article, we present construct and content validation data for both the didactic and hands-on portion of our course. Predictive validity, measuring the correlation between skill in simulator use and performance of the real-life task, is the ultimate goal in simulation training. Predictive validity is best assessed with long-term, randomized controlled studies. We look forward to conducting such studies using the ImmersiveTouch and other neurosurgical simulators and similarly hope to see validation data for the simulator described by the authors.
The authors have no personal financial or institutional interest in any of the drugs, materials, or devices described in this article.
1. Schirmer CM, Elder JB, Roitberg B, Lobel DA. Virtual reality-based simulation training for ventriculostomy: an evidence-based approach. Neurosurgery. 2013;73(suppl 4):66–73.
2. Lemole GM, Banerjee PP, Luciano C, Neckrysh S, Charbel FT. Virtual reality in neurosurgical education: part-task ventriculostomy simulation with dynamic visual and haptic feedback. Neurosurgery. 2007;61(1):142–148; discussion 148-149.
3. Cenydd LA, John NW, Phillips NI, Gray WP. VCath: a tablet-based neurosurgery training tool. Stud Health Technol Inform. 2013;184:20–23.
4. Phillips NI, John NW. Web-based surgical simulation for ventricular catheterization. Neurosurgery. 2000;46(4):933–936; discussion 936-937.