Simulation Training for Vascular Emergencies in Endoscopic Sinus and Skull Base Surgery

Pilot Validation of a 3-Dimensional Printed Pituitary Adenoma, Vascular Injury, and Cerebrospinal Fluid Leak Surgical Simulator

BACKGROUND AND OBJECTIVES

Endoscopic skull base surgery is a subspecialty field which would benefit significantly from high-fidelity surgical simulators. Giving trainees the opportunity to flatten their learning curve by practicing a variety of procedures on surgical simulators will inevitably improve patient outcomes.

METHODS

Four neurosurgeons, 8 otolarynologists, and 6 expert course faculty agreed to participate. All participants were asked to perform a transsphenoidal exposure and resection of a pituitary adenoma, repair a cerebrospinal fluid (CSF) leak, control a carotid injury, and repair a skull base defect. The content, face, and construct validity of the 3-dimensional printed model was examined.

RESULTS

The heart rate of the participants significantly increased from baseline when starting the carotid injury simulation (mean 90 vs 121, P = .029) and significantly decreased once the injury was controlled (mean 121 vs 110, P = .033, respectively). The participants reported a significant improvement in anxiety in facing a major vascular injury, as well as an increase in their confidence in management of major vascular injury, resecting a pituitary adenoma and repair of a CSF leak using a 5-point Likert scale (mean 4.42 vs 3.58 P = .05, 2 vs 3.25 P < .001, 2.36 vs 4.27 P < .001 and 2.45 vs 4.0 P = .001, respectively). The mean Objective Structured Assessment of Technical Skills score for experienced stations was 4.4, significantly higher than the Objective Structured Assessment of Technical Skills score for inexperienced stations (mean 3.65, P = .016).

CONCLUSION

We have demonstrated for the first time a validated 3-dimensional printed surgical simulator for endoscopic pituitary surgery that allows surgeons to practice a transsphenoidal approach, surgical resection of a pituitary adenoma, repair of a CSF leak in the diaphragma sellae, control of a carotid injury, and repair of skull base defect.

Internal carotid artery injury during endoscopic transsphenoidal pituitary surgery: risk factors, management

BACKGROUND

Transsphenoidal surgeons should try to avoid internal carotid artery (ICA) injury but also be prepared to manage it. We analyzed our experience with ICA injury during endoscopic transsphenoidal pituitary surgery and present associated risk factors and a management protocol.

METHODS

We retrospectively reviewed and analyzed the medical records of 1596 patients who underwent endoscopic transsphenoidal surgery for pituitary tumor resection in our institution from January 2009 to October 2022.

RESULTS

Six patients experienced an ICA injury. All received timely and effective hemostasis with immediate direct tamponade followed by endovascular treatment. No serious postoperative complications occurred.

CONCLUSIONS

We proposed a treatment plan for ICA injuries encountered during endoscopic transsphenoidal surgery and described our hemostasis process, methods of endovascular treatment, and means of postoperative follow-up in detail.

Training models and simulators for endoscopic transsphenoidal surgery: a systematic review

Endoscopic transsphenoidal surgery is a novel surgical technique requiring specific training. Different models and simulators have been recently suggested for it, but no systematic review is available. To provide a systematic and critical literature review and up-to-date description of the training models or simulators dedicated to endoscopic transsphenoidal surgery. A search was performed on PubMed and Scopus databases for articles published until February 2023; Google was also searched to document commercially available. For each model, the following features were recorded: training performed, tumor/arachnoid reproduction, assessment and validation, and cost. Of the 1199 retrieved articles, 101 were included in the final analysis. The described models can be subdivided into 5 major categories: (1) enhanced cadaveric heads; (2) animal models; (3) training artificial solutions, with increasing complexity (from "box-trainers" to multi-material, ct-based models); (4) training simulators, based on virtual or augmented reality; (5) Pre-operative planning models and simulators. Each available training model has specific advantages and limitations. Costs are high for cadaver-based solutions and vary significantly for the other solutions. Cheaper solutions seem useful only for the first stages of training. Most models do not provide a simulation of the sellar tumor, and a realistic simulation of the suprasellar arachnoid. Most artificial models do not provide a realistic and cost-efficient simulation of the most delicate and relatively common phase of surgery, i.e., tumor removal with arachnoid preservation; current research should optimize this to train future neurosurgical generations efficiently and safely.

Exploring the Role of Simulation Training in Improving Surgical Skills Among Residents: A Narrative Review

The role of simulation in medical education is crucial to the development of surgeons' skills. Surgical simulation can be used to improve surgical skills in a secure and risk-free environment. Animal models, simulated patients, virtual reality, and mannequins are some types of surgical simulation. As a result, feedback encourages students to reflect on their strengths and weaknesses, enabling them to focus on improvement. Healthcare simulation is a strong educational instrument, and the main goal of this is to give the students an opportunity to do a practical application of what they have learned through theory. Before taking it to the patients, they will already have certain tools they have previously acquired during the practice. This makes it easier for students to identify the knowledge gaps that they must fill to improve patient outcomes. Moreover, simulation brings a wonderful opportunity for students to acquire skills, gain confidence, and experience success before working with real patients, especially when their clinical exposure is limited. The use of simulation to teach technical skills to surgical trainees has become more prevalent. The cost of setting up a simulation lab ranges from $100,000 to $300,000. There are several ways to evaluate the effectiveness of simulation-based surgical training. Repetitive surgical simulation training can improve speed and fluidity in general surgical skills in comparison to conventional training. Few previous studies compared learners who received structured simulation training to a group of trainees who did not receive any simulation training in single-center randomized control research. Significantly faster and less time-consuming skill proficiency was noticeable in simulated trainees. Despite being anxious in the operating room for the first time, simulated trainees completed the surgery on time, demonstrating the effectiveness of surgical simulation training. Traditional surgical training involves senior-surgeon supervision in the operating room. In simulation-based training, the trainees have full control over clinical scenarios and settings; however, guidance and assessment are also crucial. Simulators allow users to practice tasks under conditions resembling real-life scenarios. Simulators can be compared with traditional surgical training methods for different reasons. For example, intraoperative bleeding may occasionally show up not only visibly on the screen but also by shaking the trocars erratically. Without haptics, training on virtual simulators can cause one's pulling and pushing forces, which are frequently greater than what the tissue needs, to be distorted. A good method of simulation training is using virtual reality simulators with haptics and simulated patients. The availability of these facilities is limited, though, and a typical session might include an exercise involving stacking sugar cubes and box trainers. The degree of expertise or competency is one area that needs clarification as medical education transitions to a competency-based paradigm. The article aims to provide an overview of simulation, methods of simulation training, and the key role and importance of surgical simulation in improving skills in surgical residents.

Major Internal Carotid Artery Injury During Endoscopic Skull Base Surgery: Case Report

Major vascular structures are always at risk during complex skull base surgery, particularly with use of the endoscopic endonasal approach, and intraoperative damage of the internal carotid artery (ICA) can be a devastating complication. Herein, we report a case of a young patient who had a major injury of the left ICA during endoscopic resection of a recurrent petrous bone chordoma. Massive bleeding was controlled by a Foley balloon inserted and kept in the resection area. Urgent angiography revealed a persistent leak from the petrous segment of the left ICA, and the vessel was sacrificed with coiling, since a balloon occlusion test showed good collateral blood flow. The patient woke up from anesthesia without a neurological deficit. Salvage resection of recurrent skull base neoplasms deserves specific attention because of the possibility of major vascular damage. In cases of intraoperative ICA injury, its management requires immediate decisions, and the available possibilities for endovascular therapy should always be considered.

Carotid artery injury in endoscopic endonasal surgery: Risk factors, prevention, and management

Objective

Endoscopic approaches for sinus and skull base surgery are increasing in popularity. The objective of this narrative review is to characterize risk factors for internal carotid artery injury in endoscopic endonasal surgery (EES), highlight preventative measures, and illustrate key management principles.

Data Sources

Comprehensive literature review.

Methods

Relevant literature was reviewed using PubMed/MEDLINE.

Results

Carotid artery injury in EES is rare, with most studies reporting an incidence below 0.1%. Anatomic aberrancies, wide dissection margins, as well as specific provider and hospital factors, may increase the risk of injury. Multidisciplinary teams, comprehensive preoperative imaging, patient risk assessment, and formal training in vascular emergencies may reduce the risk. Management protocols should emphasize proper visualization of the injury site, fluid replacement, rapid packing, angiography, and endovascular techniques to achieve hemostasis.

Conclusions

While EES is a relatively safe procedure, carotid artery injury is a devastating complication that warrants full consideration in surgical planning. Important preventative measures include identifying patients with notable risk factors and obtaining preoperative imaging. Multidisciplinary teams and management protocols are ultimately necessary to reduce morbidity and mortality.

Internal carotid artery (ICA) injury is a rare complication of endoscopic endonasal surgery.

Risk factors for ICA injury may include vascular anatomic variants, invasive pathology, and prior radiation therapy.

Surgical team preparation and experience are key to successful management of operative complications.

Establishing a Multidisciplinary Cavernous Carotid Injury Simulation to Train Neurosurgical, Otolaryngology, and Anesthesia Residents

Carotid artery injuries are serious complications of endoscopic endonasal surgery. As these occur rarely, simulation training offers an avenue for technique and algorithm development in resident learners. This study develops a realistic cadaveric model for the training of crisis resource management in the setting of cavernous carotid artery injury. An expanded endonasal approach and right cavernous carotid injury is performed on a cadaveric head. The cadaver's right common carotid artery is cannulated and connected to a perfusion pump delivering pressurized simulated blood. A simulation mannequin is incorporated into the model to allow for vital sign feedback. Surgical and anesthesia resident learners are tasked with obtaining vascular control with a muscle patch technique and medical management over the course of 3 clinical scenarios with increasing complexity. Crisis management instructions for an endoscopic endonasal approach to the cavernous carotid artery and blood pressure control were provided to the learners prior to beginning the simulation. An independent reviewer evaluated the learners on communication skills, crisis management algorithms, and implementation of appropriate skill sets. After each scenario, residents were debriefed on how to improve technique based on evaluation scores in areas of situational awareness, decision-making, communications and teamwork, and leadership. After the simulation, learners provided feedback on the simulation and this data was used to improve future simulations. The benefit of this cadaveric model is ease of set-up, cost-effectiveness, and reproducibility.

Development of a Cadaveric Multiport Model of Posterior Circulation Aneurysm Clipping for Neurosurgery and Otolaryngology Residents

Posterior circulation aneurysms are difficult to treat with the current methods of coiling and clipping. To address limitations in training, we developed a cadaveric model to train learners on endoscopic clipping of posterior circulation aneurysms. An endoscopic transclival approach (ETA) and a transorbital precaruncular approach (TOPA) to successfully access and clip aneurysms of the posterior circulation are described. The model has flexibility in that a colored silicone compound can be injected into the cadaveric vessels for the purpose of training learners on vascular anatomy. The other option is that the model could be connected to a vascular perfusion pump allowing real-time appreciation of a pulsatile or ruptured aneurysm. This cadaveric model is the first of its kind for training of endoscopic clipping of posterior circulation aneurysms. Learners will develop proficiency in endoscopic skills, appropriate dissection, and appreciation for relative anatomy while developing an algorithm that can be employed in a real operative arena. Going forward, various clinical scenarios can be developed to enhance the realism, allow learners from different specialties to work together, and emphasize the importance of teamwork and effective communication.

Management of an Internal Carotid Artery Injury During Open Skull Base Surgery With a Crushed Muscle Patch - Technical Note and Lessons Learned

BACKGROUND

Iatrogenic internal carotid artery (ICA) injury is a catastrophic complication in open skull base surgery. There is a lack of information regarding the most appropriate techniques on how to manage this complication.

OBJECTIVE

To highlight the difficulties encountered when an ICA injury arises intraoperatively and discuss the role and the potential pitfalls of the crushed muscle patch in the management of an ICA injury during open skull base surgery.

METHODS

In this technical video, we demonstrate the management of intraoperative ICA injury, which occurred during the resection of a diffuse planum sphenoidale meningioma via a left pterional craniotomy.

RESULTS

When isolation of the defect with temporary clips failed, we opted for a crushed muscle graft to plug the defect. Hemostasis was achieved, but because of prolonged pressure application and "overpacking," the parent vessel was occluded.

CONCLUSION

The crushed muscle patch can be easily applied; however, care must be taken not to "overpack" and occlude the ICA.

Comparative analysis of the results of video-assisted thoracic surgery lobectomy simulation using the three-dimensional-printed Biotexture wet-lung model and surgeons' experience

OBJECTIVES

We performed a comparative analysis of the performance of video-assisted thoracic surgery (VATS) lobectomy simulation using three-dimensional-printed Biotexture lung models by surgeons classified according to their level of expertise. The aim of this study was to investigate the association between surgeons' experience and time to complete the VATS lobectomy simulation.

METHODS

Participants were divided into 3 groups: group A included those who had no experience of actual VATS lobectomy (n = 11), group B included those who had performed 5-10 VATS lobectomies (n = 12) and group C included those who had performed >100 VATS lobectomies (n = 6). Their performances were assessed based on total procedure time, duration to the exposure of the vessels, ligation of the arteries and stapling of the fissures. After the simulation, a questionnaire survey was performed.

RESULTS

The median total procedure time was significantly shorter in the group of surgeons with more experience (A vs B, P < 0.001; B vs C, P = 0.034; A vs C, P < 0.001). Regarding 'the exposure of all the vessels to be resected' and 'ligation of the arteries', group B completed these steps in less time than group A (P = 0.024 and P = 0.012, respectively). In the questionnaire, all groups answered that this simulation was useful for novices to improve their skills.

CONCLUSIONS

Although time to complete the VATS lobectomy simulation is only a part of evaluation points for real skills, this model can facilitate basic skill acquisitions for novices.

Creative and Innovative Methods and Techniques for the Challenges in the Management of Adult Craniopharyngioma

Craniopharyngioma remains a major challenge in daily clinical practice. The pathobiology of the tumor is still elusive, and there are no consensus or treatment guidelines on the optimal management strategy for this relatively rare tumor. However, recent technical and scientific advances, including genomic and radiomic profiling, innovation in surgical approaches, more precise radiotherapy protocols, targeted therapy, and restoration of lost functions all have the potential to significantly improve the outcome of patients with craniopharyngioma in the near future. Although many of these innovative tools in the new armamentarium of the clinician are still in their infancy, they could reduce craniopharyngioma-related morbidity and mortality and improve the patients' quality of life. In this article, we discuss these creative and innovative approaches that may offer solutions to the obstacles faced in treating craniopharyngioma and future possibilities in improving the care of these patients.

Simulation of Pediatric Anterior Skull Base Anatomy Using a 3D Printed Model

OBJECTIVE

The pediatric skull base may present anatomic challenges to the skull base surgeon, including limited sphenoid pneumatization and a narrow nasal corridor. The rare nature of pediatric skull base pathology makes it difficult to gain experience with these anatomic challenges. The objective of this study was to create a 3-dimensionally (3D) printed model of the pediatric skull base and assess its potential as a training tool.

METHODS

Twenty-eight participants at various stages of training and practice were included in our study. They completed a pre- and postdissection questionnaire assessing challenges with endoscopic endonasal skeletonization of the carotid arteries and sella face using the 3D printed model.

RESULTS

The majority of participants had completed a skull base surgery fellowship (60.7%), were <5 years into practice (60.7%), and had <10 cases of pediatric skull base experience (82.1%). Anticipated challenges included limitation of maneuverability of instruments (71.4%), narrow nasal corridor and nonpneumatized bone (57.1%). On a scale of 0-10, 10 being very difficult, the average participant expected level of difficulty with visualization was 6.89 and expected level of difficulty with instrumentation was 7.3. On postdissection assessment, there was a nonstatistically significant change to 6.93 and 7.5, respectively. Participants endorsed on a scale of 0-10, 10 being very realistic, an overall model realism of 7.0 and haptic realism of 7.1.

CONCLUSIONS

A 3D printed model of the pediatric skull base may provide a realistic model to help participants gain experience with anatomic limitations characteristic of the pediatric anterior skull base.

Design, Development, and Validation of a High-Fidelity “Ganglion Cyst” Model for Cadaveric Hand Surgery Training

Introduction This study presents a design and developmental model with prospective validation. This study was aimed to design, develop, and validate a cadaveric model simulator of a ganglion cyst to train surgeons in its surgical excision.

Materials and Methods A novel “ganglion cyst” was designed using a latex powder-free glove and water-based, water-soluble lubricant (K-Y jelly). This “ganglion cyst” was then inserted subcutaneously into a cadaveric hand, positioned over the dorsum of the wrist to simulate a ganglion lesion. This simulation model was prospectively validated using postsimulation surveys conducted on novices and experts in hand surgery. The simulation was conducted during a basic hand surgery cadaveric workshop that included a practical station on ganglion excision.

Results Both the novices and experts had a concurrent agreement that the simulator provided relevance, realism, and value as a simulator for the teaching, excision and procedural assessment of ganglions in the hand.

Conclusion The role of high-fidelity simulation has been documented in the literature for surgical procedures. This simple and affordable model that we have developed and validated allows for the creation of a high-fidelity ganglion simulator in the cadaveric hand for teaching, excision, and procedural assessment among trainees.

Costs and training results of an objectively validated cadaveric perfusion-based internal carotid artery injury simulation during endoscopic skull base surgery

BACKGROUND

Internal carotid artery injury (ICAI) is a rare, life-threatening complication of endoscopic endonasal approaches (EEAs). High-fidelity simulation methods exist, but optimization of the training cohort, training paradigm, and costs of simulation training remain unknown.

METHODS

Using our previously validated, high-fidelity, perfused-cadaver model, participants attempted to manage a simulated ICAI. After a brief instructional video and coaching, the simulation was repeated. Training success was defined as successful ICAI control on the second attempt after failure on the initial attempt. Marginal costs were measured.

RESULTS

Seventy-two surgeons participated in the standardized simulation, which lasted ≤15 minutes. The marginal cost of simulation was $275.00 per surgeon. A total of 44.4% (n = 32) succeeded on the first attempt before training (previously proficient); 44.4% (n = 32) failed the first attempt, but succeeded after training (training successes); and 11.1% (n = 8) failed both attempts. The cost per training success was $618.75. Forty-two surgeons had never treated an ICAI, with 24 becoming training successes (57.1% overall, 82.8% when excluding previously proficient surgeons). Twenty-nine had experienced a real or simulated ICAI, with 8 (27.6% overall, 72.7% excluding previously proficient surgeons) becoming training successes. The cost per training success was lowest in the ICAI-naive group ($481.25) and highest among surgeons with simulated and real ICAI experience ($1650).

CONCLUSIONS

Surgeons can be trained to manage ICAI in a single, brief, low-cost session. Although all groups improved, training an ICAI-naive or resident cohort may maximize training results. A perfused-cadaver model is a reproducible, realistic, and low-cost method for training surgeons to manage life-threatening ICAI during an EEA.

Surgical simulation of a catastrophic internal carotid artery injury: a laser-sintered model

BACKGROUND

The catastrophic and rare nature of an internal carotid artery (ICA) injury during endonasal surgery limits training opportunities. Cadaveric and animal simulation models have been proposed, but expense and complicated logistics have limited their adoption. Three-dimensional (3D) printed models are portable, modular, reusable, less costly, and proven to improve psychomotor skills required for managing different lesions. In this study we evaluate the role of a simplified laser-sintered model combined with standardized training in improving the effectiveness of managing an ICA injury endoscopically.

METHODS

A 3-mm defect was created in the parasellar carotid canal of a laser-sintered model representing a sphenoid sinus. Artificial blood was directed to simulate the copious bleeding arising from an ICA injury. Twenty otolaryngologists and 26 neurosurgeons, with varying training and experience levels, were individually asked to stop the "bleeding" as they would in a clinical scenario, and provided no other instructions. This was followed by individualized formative training and a second simulation. Volume of blood loss, time to hemostasis, and self-assessed confidence scores were compared.

RESULTS

At the end of the study, time to hemostasis was reduced from 105.49 seconds to 40.41 seconds (p < 0.001). The volume of blood loss was reduced from 690 to 272 mL (p < 0.001), and the confidence scores increased in 95.7% of participants, from an average of 3 up to 8.

CONCLUSION

This ICA injury model, along with a formal training algorithm, appears to be valuable, realistic, portable, and cost-effective. Significant improvement in all parameters suggests the acquisition of psychomotor skills required to control an ICA injury.

Objective Validation of Perfusion-Based Human Cadaveric Simulation Training Model for Management of Internal Carotid Artery Injury in Endoscopic Endonasal Sinus and Skull Base Surgery

BACKGROUND

The emergence of minimally invasive endoscopic endonasal skull base surgery has necessitated reproducible and realistic simulators of rare vascular injuries.

OBJECTIVE

To assess the face and content validity of an innovative perfusion-based cadaveric model developed to simulate internal carotid artery (ICA) injury during endoscopic surgery.

METHODS

Otolaryngology and neurosurgery trainees attempted 3 consecutive trials of endoscopic control of a parasellar ICA injury, with standardized technical feedback. Time to hemostasis (TTH) and blood loss were trended. All participants completed validated questionnaires using a 5-point Likert scale to assess the domains of confidence gain, face validity, content validity, and curriculum applicability.

RESULTS

Among all participants (n = 35), TTH and mean blood loss significantly decreased between first vs second attempt (P = .005), and first vs third attempt (P = .03). Following the first attempt, trainees experienced an average 63% reduction in blood loss and 59% reduction in TTH. In the quartile of most improved participants, average blood loss reduction was 1115 mL (84% reduction) and TTH of 259 s (84% reduction). There were no significant differences between trainees of varying postgraduate year or specialty. Average pre and postprocedural confidence scores were 1.38 and 3.16, respectively (P &lt; .0001). All trainees reported model realism, which achieved mean face validity 4.82 ± 0.41 and content validity 4.88 ± 0.33.

CONCLUSION

The perfusion-based human cadaveric ICA injury model achieves high ratings of face and content validity across all levels of surgical trainees, and enables safe, realistic simulation for standardized skull base simulation and future curriculum development. Objective improvements in performance metrics may translate to improved patient outcomes.

Injury of the Carotid Artery during Endoscopic Endonasal Surgery: Surveys of Skull Base Surgeons

Objectives  This study aimed to review endoscopic skull base surgeon experience with internal carotid artery (ICA) injuries during endoscopic endonasal surgery (EES) to provide an estimate of the incidence of ICA injury, the associated factors and identify the best training modalities for the management of this complication. Design  Anonymous electronic survey of past participants at a well-established endoscopic skull base surgery course and a global online community of skull base surgeons. Main Outcome Measures  Relative incidence of ICA injuries during EES, associated anatomic and intraoperative factors, and surgeon experience. Results  At least 20% of surgeons in each surveyed population experienced a carotid artery injury. Reported carotid artery injuries were most common during tumor exposure and removal (48%). The parasellar carotid artery was the most commonly injured segment (39%). Carotid artery injuries were more common in high-volume surgeons, but only statistically significant in one of the two populations. Attendance at a skull base course or courses did not change the incidence of carotid artery injury in either surveyed population. In both surveys, respondents preferred live surgeries or active (not computer simulated) training models. Conclusions  ICA injury is underreported and most common when manipulating the parasellar carotid artery for exposure and tumor dissection. Given the high morbidity and mortality associated with these injuries, vascular injury management should be prioritized and taught in a graduated approach by modern endoscopic skull base courses.

Innovations in surgery simulation: a review of past, current and future techniques

As a result of recent work-hours limitations and concerns for patient safety, innovations in extraclinical surgical simulation have become a desired part of residency education. Current simulation models, including cadaveric, animal, bench-top, virtual reality (VR) and robotic simulators are increasingly used in surgical training programs. Advances in telesurgery, three-dimensional (3D) printing, and the incorporation of patient-specific anatomy are paving the way for simulators to become integral components of medical training in the future. Evidence from the literature highlights the benefits of including simulations in surgical training; skills acquired through simulations translate into improvements in operating room performance. Moreover, simulations are rapidly incorporating new medical technologies and offer increasingly high-fidelity recreations of procedures. As a result, both novice and expert surgeons are able to benefit from their use. As dedicated, structured curricula are developed that incorporate simulations into daily resident training, simulated surgeries will strengthen the surgeon's skill set, decrease hospital costs, and improve patient outcomes.