Applications of Head-Mounted Displays and Smart Glasses in Vascular Surgery.

OBJECTIVES: Advances in virtual, augmented and mixed reality have led to the development of wearable technologies including head mounted displays (HMD) and smart glasses. While there is a growing interest on their potential applications in health, only a few studies have addressed so far their use in vascular surgery. The aim of this review was to summarize the fundamental notions associated with these technologies and to discuss potential applications and current limits for their use in vascular surgery. METHODS: A comprehensive literature review was performed to introduce the fundamental concepts and provide an overview of applications of HMD and smart glasses in surgery. RESULTS: HMD and smart glasses demonstrated a potential interest for the education of surgeons including anatomical teaching, surgical training, teaching and telementoring. Applications for pre-surgical planning have been developed in general and cardiac surgery and could be transposed for a use in vascular surgery. The use of wearable technologies in the operating room has also been investigated in both general and cardiovascular surgery and demonstrated its potential interest for image-guided surgery and data collection. CONCLUSION: Studies performed so far represent a proof of concept of the interest of HMD and smart glasses in vascular surgery for education of surgeons and for surgical practice. Although these technologies exhibited encouraging results for applications in vascular surgery, technical improvements and further clinical research in large series are required before hoping using them in daily clinical practice.

EyeSi Surgical Simulator: validation of a proficiency-based test for assessment of vitreoretinal surgical skills.

PURPOSE: To develop and investigate an evidence-based performance test for assessment of vitreoretinal surgical skills on the EyeSi Surgical Simulator. METHODS: Ten junior residents without any surgical experience, eight senior residents with prior experience in cataract surgery and five vitreoretinal surgeons were included in the study. The test consisted of seven modules and was completed twice by all groups during a single session. Validity evidence was evaluated using Messick's validity framework. Senior residents completed four additional test sessions and were retested 3 months after to assess skill acquisition and retention. RESULTS: Content was aligned with vitreoretinal surgical skills as evaluated by expert surgeons. Response process was ensured through standardized instruction and data collection. The test showed satisfactory internal consistency with Cronbach's α = 0.76 (internal structure) and significant discriminative ability between the residents and the experienced surgeons (relation to other variables). A pass/fail level was determined at 596 using the contrasting groups' method. Consequences of applying this standard resulted in no false positive and no false negative. Senior residents significantly improved their simulator skills over time, reaching a plateau at the fifth iteration and equalling expert performance (p = 0.420). This level of competency was retained during the post-3-month retention testing (p = 0.062). CONCLUSION: We established a performance test with solid evidence for assessment of vitreoretinal surgical skills on the EyeSi Simulator and determined a benchmark criterion that may be used for future implementation of proficiency-based training for novices.

What Is Your Reality? Virtual, Augmented, and Mixed Reality in Plastic Surgery Training, Education, and Practice.

SUMMARY: Virtual reality and other technological advancements both inside and outside the operating room have shown an exponential increase in the past two decades. Surgical technique and finesse in delicate procedures have become ever more important, and the onus is on plastic surgeons and plastic surgery residents to meet these needs to provide the best outcomes possible to patients. The ability to learn, simulate, and practice operating in a fashion that poses no harm to any patient is truly a gift from technology to surgery that any surgeon could benefit from, whether trainee or attending. This application of technology and simulation has been demonstrated in other fields such as in the airline industry with flight simulation. The ability to learn, synthesize, and incorporate learned materials and ideas through virtual, augmented, and mixed reality tools offers a great opportunity to put our field at the forefront of a paradigm shift in surgical education. The critical utility of digital education could not be further emphasized any more than in the unfortunate and infrequent situation of a worldwide pandemic. This article reviews some of the important recent technologies that have developed and their applications in plastic surgery education and offers a look into what we can expect in the future.

Magnetic needle-tracking device for ultrasound guidance of radial artery puncture: A randomized study on a simulation model.

INTRODUCTION: Ultrasound-guidance of radial artery catheter insertion improves the first attempt success and reduces the occurrence of hematomas. Needle-tracking devices optimize needle-ultrasound beam alignment by displaying in real-time the needle tip position. We compared the median time need by experienced physicians to achieve radial artery puncture using either a conventional ultrasonography device (CUD) or a magnetic needle-tracking ultrasound device (MUD) in a simulation training arm model. METHODS: Fifty experienced residents and physicians performed two punctures in randomized order with the CUD and the MUD. The primary outcome was puncture duration; the secondary outcomes were puncture success, rate of accidental vein puncture, and practitioner's comfort (subjective scale 0-10). RESULTS: The median [lower-upper quartile] puncture time was 10 [6-14] seconds when using CUD and 4 [3-7] seconds when using MUD (P < .01). In the multivariate analysis, MUD use was associated with decreased puncture duration whatever the puncture order (OR 1.13 [1.07-1.20], P < .01). The participants performed 99 (99%) successful punctures: 50 with the MUD (100%) and 49 with the CUD (98%). There was no accidental venous puncture. The practitioner's comfort level was 6.5 [6, 7] with the CUD and 8 [7-9] with the MUD (P < .01). CONCLUSION: MUD reduced radial artery puncture time and improved physician comfort in a simulation training arm model.

Image-Guided Surgical Training in Percutaneous Hepatobiliary Procedures: Development of a Realistic and Meaningful Bile Duct Dilatation Porcine Model.

Background: Malignant or benign biliary obstructions can be successfully managed with minimally invasive percutaneous interventions. Since percutaneous approaches are challenging, extensive training using relevant models is fundamental to improve the proficiency of percutaneous physicians. The aim of this experimental study was to develop an in vivo training model in pigs to simulate bile duct dilatation to be used during percutaneous biliary interventions. Materials and Methods: Twenty-eight large white pigs were involved and procedures were performed in an experimental hybrid operating room. Under general anesthesia, animals underwent a preoperative magnetic resonance cholangiography (MRC). Afterward, the common bile duct was isolated and ligated laparoscopically. A postoperative MRC was performed 72 hours after the procedure to evaluate bile duct dilatation. The In vivo models presenting an effective dilatation model were included in the hands-on part of a percutaneous surgery training course. Animals were euthanized at the end of the training session. Results: Postoperative MRC confirmed the presence of bile duct dilatation in the survival pigs (n = 25). No intraoperative complications occurred and mean operative time was 15.8 ± 5.27 minutes. During the course, 27 trainees could effectively perform percutaneous transhepatic cholangiography, bile duct drainage, biliary duct dilatation, and stent placement, with a > 90% success rate, thereby validating the experimental model. All animals survived during the training procedures and complications occurred in 28.3% of cases. Conclusion: The creation of an in vivo bile duct dilatation animal model is feasible with a low short-term mortality. It provides a realistic and meaningful training model in percutaneous biliary procedures.

Feasibility of fresh frozen human cadavers as a research and training model for endovascular image guided interventions.

OBJECTIVE: To describe the feasibility of a fresh frozen human cadaver model for research and training of endovascular image guided procedures in the aorta and lower extremity. METHODS: The cadaver model was constructed in fresh frozen human cadaver torsos and lower extremities. Endovascular access was acquired by inserting a sheath in the femoral artery. The arterial segment of the specimen was restricted by ligation of collateral arteries and, in the torsos, clamping of the contralateral femoral artery and balloon occlusion of the supratruncal aorta. Tap water was administered through the sheath to create sufficient intraluminal pressure to manipulate devices and acquire digital subtraction angiography (DSA). Endovascular cannulation tasks of the visceral arteries (torso) or the peripheral arteries (lower extremities) were performed to assess the vascular patency of the model. Feasibility of this model is based on our institute's experiences throughout the use of six fresh frozen human cadaver torsos and 22 lower extremities. RESULTS: Endovascular simulation in the aortic and peripheral vasculature was achieved using this human cadaver model. Acquisition of DSA images was feasible in both the torsos and the lower extremities. Approximately 84 of the 90 target vessels (93.3%) were patent, the remaining six vessels showed signs of calcified steno-occlusive disease. CONCLUSIONS: Fresh frozen human cadavers provide a feasible simulation model for aortic and peripheral endovascular interventions, and can potentially reduce the need for animal experimentation. This model is suitable for the evaluation of new endovascular devices and techniques or to master endovascular skills.

Use of ultrasound guidance in central venous catheter placement by emergency physicians in Saudi Arabia.

OBJECTIVES: To determine the ultrasound guidance for central venous catheter (USG-CVC) placement rate of emergency physicians (EPs) in Kingdom of Saudi Arabia. METHODS: A cross-sectional survey study regarding the respondents' demographic profiles, formal and informal training in USG-CVC placement, experiences, and attitudes towards the procedure was emailed to all EPs registered with the Saudi Commission for Health Specialties (SCFHS) between October and December 2018. RESULTS: In total, 234/350 SCFHS-registered EPs completed the survey; the response rate was 66.9%. Most respondents (70.5%) were board-certified in emergency medicine (EM). Ninety percent indicated that US device for CVC placement assistance was available. Most EPs (78.2%) had performed USG-CVC placement; the US usage rate correlated significantly with recent graduation from residency (p=0.048). In total, 83.3% received formal training during residency. Of the 234 respondents, 53.8% felt extremely comfortable with CVC placement with USG and 19.7% without USG (p less than 0.01). Nevertheless, most respondents desired further USG-CVC training. CONCLUSION: Despite existing evidence and a consensus on its superiority over the landmark technique, USG-CVC placement has not been adopted by a small proportion of EPs into clinical practice. Formal training, education, and institutional provision of permanent onsite US machines may address any barriers.

Simulation-based training using a vessel phantom effectively improved first attempt success and dynamic needle-tip positioning ability for ultrasound-guided radial artery cannulation in real patients: An assessor-blinded randomized controlled study.

BACKGROUND: We evaluated whether a simulation-based training with a vessel phantom improves the basic skills of a novice required for ultrasound-guided radial artery cannulation in real patients. In addition, we analysed whether repeated simulation training sets with an inter-training interval would accelerate the learning curve. METHODS: From March 2019 to July 2019, twenty-one anesthesiology residents were randomized into either a simulation group (n = 11) or control group (n = 10). Residents performed a total of 84 ultrasound-guided radial artery cannulations in real patients. The simulation group participated in two sets of simulation training on a vessel phantom (10 sessions per set) with a one-month inter-training interval. Trainee's performance proficiency was scored using a developed checklist, and a learning curve for each training set was constructed. To evaluate the effectiveness of our training curriculum in skill transfer, each resident performed four ultrasound-guided radial artery cannulations in real patients. The primary outcome was first attempt success rate and the secondary outcome was dynamic needle-tip positioning ability in real patients. RESULTS: The first attempt success rate and dynamic needle-tip positioning ability by ultrasound transducer were significantly higher in the simulation group than the control group (81.8% vs. 50%, P = 0.002 and 68.2% vs. 7.5%, P < 0.001, respectively). A reduced number of sessions was required to reach a plateau score on the learning curve in the repeated training set compared in the first-set (7 (5-8) vs. 3 (2-4), P = 0.003, respectively). CONCLUSIONS: Simulation-based training using a vessel phantom effectively improved the first attempt success rate for ultrasound-guided radial artery cannulation in real patients and the dynamic needle-tip positioning ability by ultrasound transducer in novice anesthesiology residents. In addition, repeated training curriculum accelerated the learning curve for recall skill proficiency and reduced inter-individual variability for skill acquisition. CLINICAL TRIAL REGISTRATION: Clinical Research Information Service (KCT0003471, Principle investigator: Jeong Jin Min, Date of registration: 06/March/2019).

Simulation of advanced cataract surgery - validation of a newly developed test.

PURPOSE: To develop and investigate an Eyesi simulator-based test for the more experienced cataract surgeon for evidence of validity. METHODS: The study was a prospective interventional cohort study and carried out at the Copenhagen Academy for Medical Education and Simulation. The Eyesi Simulator was used for the test which was developed by three expert cataract surgeons. Ten cataract surgeons (>250 surgeries performed) and ten ophthalmic residents performed two repetitions of the test. The test consisted of four modules: Iris Expansion Ring insertion - level 1, Iris Expansion Ring extraction - level 2, Capsulorhexis - level 3 and Anterior Vitrectomy - level 6. RESULTS: Internal consistency reliability showed Cronbach's alpha of 0.63. Test-retest reliabilities were significant for Iris Expansion Ring extraction - level 2 (p = 0.012) and Capsulorhexis - level 3 (p = 0.018). Differences between the two groups were only significant in both repetitions for the Iris Expansion Ring extraction - level 2 (p < 0.001 and p = 0.041, respectively). Furthermore, we found a statistically significant difference between the mean module scores for novices and the more experienced surgeons for Iris Expansion Ring insertion - level 1 (p = 0.021) and Capsulorhexis - level 3 (p = 0.019) in the first repetition. CONCLUSION: The investigated modules show evidence of validity within several aspects of Messick's framework. However, the evidence is not strong enough to apply the test for certification purposes of cataract surgeons, but the modules may still be relevant in the training of advanced cataract surgical procedures.

The Virtual Operative Assistant: An explainable artificial intelligence tool for simulation-based training in surgery and medicine.

Simulation-based training is increasingly being used for assessment and training of psychomotor skills involved in medicine. The application of artificial intelligence and machine learning technologies has provided new methodologies to utilize large amounts of data for educational purposes. A significant criticism of the use of artificial intelligence in education has been a lack of transparency in the algorithms' decision-making processes. This study aims to 1) introduce a new framework using explainable artificial intelligence for simulation-based training in surgery, and 2) validate the framework by creating the Virtual Operative Assistant, an automated educational feedback platform. Twenty-eight skilled participants (14 staff neurosurgeons, 4 fellows, 10 PGY 4-6 residents) and 22 novice participants (10 PGY 1-3 residents, 12 medical students) took part in this study. Participants performed a virtual reality subpial brain tumor resection task on the NeuroVR simulator using a simulated ultrasonic aspirator and bipolar. Metrics of performance were developed, and leave-one-out cross validation was employed to train and validate a support vector machine in Matlab. The classifier was combined with a unique educational system to build the Virtual Operative Assistant which provides users with automated feedback on their metric performance with regards to expert proficiency performance benchmarks. The Virtual Operative Assistant successfully classified skilled and novice participants using 4 metrics with an accuracy, specificity and sensitivity of 92, 82 and 100%, respectively. A 2-step feedback system was developed to provide participants with an immediate visual representation of their standing related to expert proficiency performance benchmarks. The educational system outlined establishes a basis for the potential role of integrating artificial intelligence and virtual reality simulation into surgical educational teaching. The potential of linking expertise classification, objective feedback based on proficiency benchmarks, and instructor input creates a novel educational tool by integrating these three components into a formative educational paradigm.

Virtual vitreoretinal surgery: effect of distracting factors on surgical performance in medical students.

PURPOSE: We aimed to investigate the effect of four distracting factors on surgical performance in virtual vitreoretinal surgery. METHODS: Nineteen novice surgeons completed a validated training programme on the Eyesi surgical simulator (VRmagic GmbH, Manheim, Germany; software version 2.9.2) until a calculated target score was reached. The training programme consisted of four modules: navigation level 2 (Nav2), bimanual training level 3 (BimT3), posterior hyaloid level 3 (PostH3) and internal limiting membrane peeling level 3 (ILMP3). When properly trained, the participants completed the training programme once without distraction to generate reference scores and times. Next, they conducted the training programme under the influence of each of the following: auditory distraction, 12 hr of fasting, interrupted sleep and 24 hr of sleep deprivation. Wilcoxon signed-rank test was used to compare the distraction-induced results to the participants' reference scores and times. RESULTS: As compared to reference score (328), a lower performance was found for all four distractions: auditory distraction (289, p = 0.0012), fasting (302, p = 0.02), sleep interruption (304, p = 0.02) and sleep deprivation (300, p = 0.0006). In particular, PostH3 performance was influenced by all four interventions. (86 versus 50, p = 0,0012, 65, p = 0.05, 72, p = 0.05, 54, p = 0.0007 respectively). CONCLUSIONS: Virtual vitreoretinal surgery is an important tool for practicing complex surgical skills without compromising patient safety. In this study, deleterious effects on surgical performance were induced by four independent distracting factors. This knowledge is useful to optimize surgeons' work conditions and ensuring the best possible treatment of patients.

A microsurgical robot research platform for robot-assisted microsurgery research and training.

PURPOSE: Ocular surgery, ear, nose and throat surgery and neurosurgery are typical types of microsurgery. A versatile training platform can assist microsurgical skills development and accelerate the uptake of robot-assisted microsurgery (RAMS). However, the currently available platforms are mainly designed for macro-scale minimally invasive surgery. There is a need to develop a dedicated microsurgical robot research platform for both research and clinical training. METHODS: A microsurgical robot research platform (MRRP) is introduced in this paper. The hardware system includes a slave robot with bimanual manipulators, two master controllers and a vision system. It is flexible to support multiple microsurgical tools. The software architecture is developed based on the robot operating system, which is extensible at high-level control. The selection of master-slave mapping strategy was explored, while comparisons were made between different interfaces. RESULTS: Experimental verification was conducted based on two microsurgical tasks for training evaluation, i.e. trajectory following and targeting. User study results indicated that the proposed hybrid interface is more effective than the traditional approach in terms of frequency of clutching, task completion time and ease of control. CONCLUSION: Results indicated that the MRRP can be utilized for microsurgical skills training, since motion kinematic data and vision data can provide objective means of verification and scoring. The proposed system can further be used for verifying high-level control algorithms and task automation for RAMS research.

Incorporation and validation of clinically relevant performance metrics of simulation (CRPMS) into a novel full-immersion simulation platform for nerve-sparing robot-assisted radical prostatectomy (NS-RARP) utilizing three-dimensional printing and hydrogel casting technology.

OBJECTIVES: To incorporate and validate clinically relevant performance metrics of simulation (CRPMS) into a hydrogel model for nerve-sparing robot-assisted radical prostatectomy (NS-RARP). MATERIALS AND METHODS: Anatomically accurate models of the human pelvis, bladder, prostate, urethra, neurovascular bundle (NVB) and relevant adjacent structures were created from patient MRI by injecting polyvinyl alcohol (PVA) hydrogels into three-dimensionally printed injection molds. The following steps of NS-RARP were simulated: bladder neck dissection; seminal vesicle mobilization; NVB dissection; and urethrovesical anastomosis (UVA). Five experts (caseload >500) and nine novices (caseload <50) completed the simulation. Force applied to the NVB during the dissection was quantified by a novel tension wire sensor system fabricated into the NVB. Post-simulation margin status (assessed by induction of chemiluminescent reaction with fluorescent dye mixed into the prostate PVA) and UVA weathertightness (via a standard 180-mL leak test) were also assessed. Objective scoring, using Global Evaluative Assessment of Robotic Skills (GEARS) and Robotic Anastomosis Competency Evaluation (RACE), was performed by two blinded surgeons. GEARS scores were correlated with forces applied to the NVB, and RACE scores were correlated with UVA leak rates. RESULTS: The expert group achieved faster task-specific times for nerve-sparing (P = 0.007) and superior surgical margin results (P = 0.011). Nerve forces applied were significantly lower for the expert group with regard to maximum force (P = 0.011), average force (P = 0.011), peak frequency (P = 0.027) and total energy (P = 0.003). Higher force sensitivity (subcategory of GEARS score) and total GEARS score correlated with lower nerve forces (total energy in Joules) applied to NVB during the simulation with a correlation coefficient (r value) of -0.66 (P = 0.019) and -0.87 (P = 0.000), respectively. Both total and force sensitivity GEARS scores were significantly higher in the expert group compared to the novice group (P = 0.003). UVA leak rate highly correlated with total RACE score r value = -0.86 (P = 0.000). Mean RACE scores were also significantly different between novices and experts (P = 0.003). CONCLUSION: We present a realistic, feedback-driven, full-immersion simulation platform for the development and evaluation of surgical skills pertinent to NS-RARP. The correlation of validated objective metrics (GEARS and RACE) with our CRPMS suggests their application as a novel method for real-time assessment and feedback during robotic surgery training. Further work is required to assess the ability to predict live surgical outcomes.

Towards near real-time assessment of surgical skills: A comparison of feature extraction techniques.

BACKGROUND AND OBJECTIVE: Surgical skill assessment aims to objectively evaluate and provide constructive feedback for trainee surgeons. Conventional methods require direct observation with assessment from surgical experts which are both unscalable and subjective. The recent involvement of surgical robotic systems in the operating room has facilitated the ability of automated evaluation of the expertise level of trainees for certain representative maneuvers by using machine learning for motion analysis. The features extraction technique plays a critical role in such an automated surgical skill assessment system. METHODS: We present a direct comparison of nine well-known feature extraction techniques which are statistical features, principal component analysis, discrete Fourier/Cosine transform, codebook, deep learning models and auto-encoder for automated surgical skills evaluation. Towards near real-time evaluation, we also investigate the effect of time interval on the classification accuracy and efficiency. RESULTS: We validate the study on the benchmark robotic surgical training JIGSAWS dataset. An accuracy of 95.63, 90.17 and 90.26% by the Principal Component Analysis and 96.84, 92.75 and 95.36% by the deep Convolutional Neural Network for suturing, knot tying and needle passing, respectively, highlighted the effectiveness of these two techniques in extracting the most discriminative features among different surgical skill levels. CONCLUSIONS: This study contributes toward the development of an online automated and efficient surgical skills assessment technique.

Pedicle Screw Instrumentation in Scoliosis Surgery: On Site Simulation Data on Accuracy and Efficiency With Different Techniques.

STUDY DESIGN: Prospective experimental study with on-site simulation. OBJECTIVE: To compare the accuracy and efficiency of different techniques for pedicle screw instrumentation (PSI). SUMMARY OF BACKGROUND DATA: Improving the safety and efficiency of PSI is a critical step to reduce the complication rates and the cost of scoliosis surgery. Innovative operative techniques for PSI have shown to safely improve efficiency, thereby reducing cost. Surgical simulation is a valuable tool to study different operative techniques. METHODS: Five spine fellows instrumented 20 simulation models of a scoliotic spine with 10 pedicle screws per model. Four techniques were studied, including the conventional pedicle probe and the innovative sequential drilling technique, with or without computed tomography (CT)-based navigation. Our primary outcome measures were efficiency and accuracy of PSI. We analyzed the data with bivariate analyses using the Chi-square test for categorical variables and the Student t test or ANalysis Of VAriance with Bonferroni post-hoc tests for continuous variables. RESULTS: The drilling techniques (free hand and navigated) were more efficient as compared with the pedicle probe techniques (P < 0.01). The navigated techniques resulted in better accuracy as compared with the free hand techniques (P = 0.036). Most pedicle breaches were medial (n = 32/52). The concave apical pedicle (T4 right side) had the highest incidence of breaches. There was no significant difference in efficiency comparing the free hand and the navigated pedicle probe techniques (P = 0.261) or comparing the free hand drilling and the navigated drilling techniques (P = 1.00). CONCLUSION: On site surgical simulation is a promising concept for teaching advanced procedural skills. Our findings suggest that navigation improves the accuracy of PSI while sequential drilling safely improves efficiency. Combining navigation with sequential drilling can significantly improve the accuracy and the efficiency of PSI in scoliosis surgery, as previously suggested with our published clinical data. LEVEL OF EVIDENCE: 4.

Computer navigation of the glenoid component in reverse total shoulder arthroplasty: a clinical trial to evaluate the learning curve.

BACKGROUND: Intraoperative computer navigation has been introduced recently to assist with placement of the glenoid component. The aim of this study was to evaluate the learning curve of a single surgeon performing computer navigation of glenoid implant placement in primary reverse total shoulder arthroplasty (RTSA). METHODS: Following training with the intraoperative computer navigation system, we conducted a prospective case-series study of the first 24 consecutive patients undergoing a primary RTSA with navigation performed by a single surgeon. Surgical times, complications, and accuracy of glenoid positioning compared with the preoperative plan were evaluated. Surgical times were compared with the preceding non-navigated series of 24 consecutive primary RTSA cases. Postoperative 3-dimensional computed tomography scans were performed to evaluate glenoid component version and inclination compared with the preoperative plan. RESULTS: The total surgical time was 77.3 minutes (standard deviation [SD], 11.8 minutes) in the navigated RTSA cohort and 78.5 minutes (SD, 18.1 minutes) in the non-navigated series. A significant downward trend in the total surgical time was observed in the navigated cohort (P = .038), which flattened after 8 cases. No learning curve was observed in deviation of glenoid version or inclination from the preoperative plan. The mean deviation of achieved version from planned version was 3° (SD, 2°), and the mean deviation of achieved inclination from planned inclination was 5° (SD, 3°). CONCLUSION: Findings from this study suggest that intraoperative computer navigation will not require substantially increased operating times compared with standard surgical techniques. With prior surgeon training, approximately 8 operative cases are required to achieve proficiency in intraoperative computer navigation of the glenoid component.

The effect of three-dimensional visualisation on performance in endoscopic sinus surgery: A clinical training study using surgical navigation for movement analysis in a randomised crossover design.

OBJECTIVES: Endoscopic imaging techniques and endoscopic endonasal surgery (EES) expertise have evolved rapidly. Only few studies have assessed the effect of three-dimensional (3D) endoscopy on endoscopic sinus surgery (ESS). The present study aimed to objectively and subjectively assess the additional value of 3D high-definition (HD) endoscopy in ESS. DESIGN: A randomized crossover study of endoscopic surgery performance, using five ESS tasks of varying complexity, performed on Thiel embalmed human specimens. SETTING: Simulated surgical environment. PARTICIPANTS: Thirty participants, inexperienced in ESS. MAIN OUTCOME MEASURES: Performance was assessed using video imaging, surgical navigation and questionnaires. Main outcome measures were as follows: efficiency (defined by time to task completion), distance covered inside the nose, average velocity towards target, accuracy (measured by error rate), and subjective assessment of endoscope characteristics. RESULTS: During ESS tasks, both efficiency and accuracy did not differ significantly between 2D HD and 3D HD endoscopy. Subjectively, imaging characteristics of the 3D HD endoscope were rated significantly better. CONCLUSIONS: ESS performance of inexperienced participants was not significantly improved by the use of 3D HD endoscopy during ESS tasks, although imaging characteristics of the 3D HD endoscope were rated significantly better. Surgical field characteristics and surgical techniques are likely to influence any additional value of 3D HD endoscopy.