Microsurgical Performance Research Articles

Non-cadaveric spine surgery simulator training in neurosurgical residency

BackgroundSpine surgical training faces increasing challenges due to restricted working hours and greater subspecialization. Modern simulators offer a promising approach to teaching both simple and complex spinal procedures. This study evaluated the acceptance and efficacy of spine simulator training using a lumbar herniated disc model tested by 16 neurosurgical residents (PGY-1-6), and compared 3D and 2D teaching methods. MethodsSixteen residents utilized the Realists RealSpine L4/L5 disc simulator with both microscope and exoscope. A mixed-methods analysis assessed the efficacy and acceptance of the training. Six PGY-1 residents participated in a learning curve study, divided into exoscopic and microscopic cohorts. Each group watched a tutorial in either 3D or 2D, followed by three surgical sessions. Endpoints included surgical progress within 30 minutes and complication rates. Microsurgical skills and mental concepts were evaluated on a numeric Likert Scale. ResultsParticipants rated the simulator training favorably, with a median score of 8/10 across six categories. The learning curve study showed a 30% improvement in microsurgical performance. The completion rate of herniated disc removal increased from 50% at T2 to 100% at T3 and T4. Significant improvement in mental concept was observed (p=0.035), with slightly better consolidation in the exoscope group. Self-assessments revealed significantly improved skills across all participants. ConclusionSpine simulator training was well-received and resulted in improvements in both mental concept and microsurgical performance, with enhanced outcomes in the 3D teaching/exoscope group. This study supports the integration of spine simulators into spine surgical residency, particularly for early-stage training, to improve both cognitive and practical surgical skills.

Comparing the impact of surgical expert versus non-ophthalmologist instructors on virtual-reality surgical performance: A randomized controlled trial.

To compare Manual Small Incision Cataract Surgery (MSICS) microsurgical performance in course participants who received virtual reality simulation-based training by either a surgical expert or a non-ophthalmologist instructor. Copenhagen Academy for Medical Education and Simulation, Copenhagen, Denmark. Randomized controlled trial. Residents and specialists in ophthalmology with no prior MSICS experience were included to receive virtual reality simulation training in MSICS using the HelpMeSee simulator. The participants were randomly allocated to receive training from either an experienced MSICS surgeon or a non-ophthalmologist, also known as near-peer teaching. The performances of the participants were evaluated at baseline and post-training using a MSICS proficiency-based test with evidence of validity. Thirty participants were included in the study and 29 completed the course. There was no significant difference in final test score between the two groups (p = 0.13). The performance score of both groups of participants increased significantly after receiving the training (p < 0.001). All participants passed the proficiency-based test after receiving the training. We found no significant difference in surgical proficiency-level whether the participants were trained by a surgical expert or a non-ophthalmologist instructor for MSICS in a virtual-reality based setting. The findings of this study suggest that near-peer teaching within microsurgical performance potentially could be applied with teaching outcomes comparable to a surgical expert-instructor.

Preclinical Performance of the Combined Application of Two Robotic Systems in Microsurgery: A Two-center Study.

Recent advancements in the development of robotic devices increasingly draw the attention toward the concept of robotic microsurgery, as several systems tailored to open microsurgery are being introduced. This study describes the combined application of a novel microsurgical robot, the Symani, with a novel robotic microscope, the RoboticScope, for the performance of microvascular anastomoses in a two-center preclinical trial. Six novices, residents, and experienced microsurgeons (n = 18) performed five anastomoses on 1.0-mm-diameter silicone vessels with a conventional versus combined robotic approach, resulting in 180 anastomoses. Microsurgical performance was evaluated, analyzing surgical time, subjective satisfaction with the anastomosis and robotic setup, anastomosis quality using the anastomosis lapse index score, microsurgical skills using the Structured Assessment of Microsurgery Skills score, and surgical ergonomics using the Rapid Entire Body Assessment score. All participants significantly improved their performance during the trial and quickly adapted to the novel systems. Surgical time significantly decreased, whereas satisfaction with the anastomosis and setup improved over time. The use of robotic systems was associated with fewer microsurgical errors and enhanced anastomosis quality. Especially novices demonstrated accelerated skill acquisition upon robotic assistance compared with conventional microsurgery. Moreover, upper extremity positioning was significantly improved. Overall, the robotic approach was subjectively preferred by participants. The concept of robotic microsurgery holds great potential to improve precision and ergonomics in microsurgery. This two-center trial provides promising evidence for a steep learning curve upon introduction of robotic microsurgery systems, suggesting further pursuit of their clinical integration.

Comparing the impact of three-dimensional digital visualization technology versus traditional microscopy on microsurgeons in microsurgery: a prospective self-controlled study.

Emerging three-dimensional digital visualization technology (DVT) provides more advantages than traditional microscopy in microsurgery; however, its impact on microsurgeons' visual and nervous systems and delicate microsurgery is still unclear, which hinders the wider implementation of DVT in digital visualization for microsurgery. Forty-two microsurgeons from the Zhongshan Ophthalmic Center were enrolled in this prospective self-controlled study. Each microsurgeon consecutively performed 30min conjunctival sutures using a three-dimensional digital display and a microscope, respectively. Visual function, autonomic nerve activity, and subjective symptoms were evaluated before and immediately after the operation. Visual functions, including accommodative lag, accommodative amplitude, near point of convergence and contrast sensitivity function (CSF), were measured by an expert optometrist. Heart rate variability was recorded by a wearable device for monitoring autonomic nervous activity. Subjective symptoms were evaluated by questionnaires. Microsurgical performance was assessed by the video-based Objective Structured Assessment of Technical Skill (OSATS) tool. Accommodative lag decreased from 0.63 (0.18) diopters (D) to 0.55 (0.16) D ( P =0.014), area under the log contrast sensitivity function increased from 1.49 (0.15) to 1.52 (0.14) ( P =0.037), and heart rate variability decreased from 36.00 (13.54) milliseconds (ms) to 32.26 (12.35) ms ( P =0.004) after using the DVT, but the changes showed no differences compared to traditional microscopy ( P >0.05). No statistical significance was observed for global OSATS scores between the two rounds of operations [mean difference, 0.05 (95% CI: -1.17 to 1.08) points; P =0.95]. Subjective symptoms were quite mild after using both techniques. The impact of DVT-based procedures on microsurgeons includes enhanced accommodation and sympathetic activity, but the changes and surgical performance are not significantly different from those of microscopy-based microsurgery. Our findings indicate that short-term use of DVT is reliable for microsurgery and the long-term effect of using DVT deserve more consideration.

Weight-adjusted caffeine and β-blocker use in novice versus senior retina surgeons: a self-controlled study of simulated performance.

Tremor and expertise are potentially influenced variables in vitreoretinal surgery. We investigated whether surgeon experience impacts the association of microsurgical performance with caffeine and β-blockers weight-adjusted intake. Novice and senior surgeons (<2 and >10 practice years, respectively) were recruited in this self-controlled, cross-sectional study. A simulator's task sequence was repeated over 2 days, 30 min after the following exposures: day 1, placebo, 2.5 mg/kg caffeine, 5.0 mg/kg caffeine, and 0.6 mg/kg propranolol; and day 2, placebo, 0.2 mg/kg propranolol, 0.6 mg/kg propranolol, and 5.0 mg/kg caffeine. Outcomes were total score (0-700, worst-best), simulation time (minutes), intraocular trajectory (centimeters), and tremor-specific score (0-100, worst-best). We recruited 15 novices (9 men [60%], 1.33 ± 0.49 practice years) and 11 seniors (8 men [72.7%], 16.00 ± 4.24 practice years). Novices performed worse after 2.5 mg/kg caffeine and improved following 0.2 mg/kg propranolol in total score (557 vs. 617, p = 0.009), trajectory (229.86 vs. 208.07, p = 0.048), time (14.9 vs. 12.7, p = 0.048), and tremor-score (55 vs. 75, p = 0.009). Surgical performance improved with propranolol post-caffeine but remained worse than 0.2 mg/kg propranolol in total score (570 vs. 617, p = 0.014), trajectory (226.59 vs. 208.07, p = 0.033), and tremor-score (50 vs. 75, p = 0.029). Seniors' tremor-score was lower after 2.5 mg/kg caffeine compared to 0.2 mg/kg propranolol (8 vs. 37, p = 0.015). Tremor-score following propranolol post-caffeine remained inferior to 0.6 mg/kg propranolol alone (17 vs. 38, p = 0.012). While caffeine and propranolol were associated with performance changes among novices, only tremor was affected in seniors, without dexterity changes. The pharmacologic exposure impact on surgical dexterity seems to be offset by increased experience.

Small amount of alcohol did not deteriorate microsurgical dexterity: a prospective laboratory study

BackgroundAlcohol consumption has been reported to deteriorate surgical performance both immediately after consumption as well as on the next day. We studied the early effects of alcohol consumption on microsurgical manual dexterity in a laboratory setting.MethodSix neurosurgeons or neurosurgical residents (all male) performed micro- and macro suturing tasks after consuming variable amounts of alcohol. Each participant drank 0–4 doses of alcohol (14 g ethanol). After a delay of 60–157 min, he performed a macrosurgical and microsurgical task (with a surgical microscope). The tasks consisted of cutting and re-attaching a circular latex flap (diameter: 50 mm macrosuturing, 4 mm microsuturing) with eight interrupted sutures (4–0 multifilament macrosutures, 9–0 monofilament microsutures). We measured the time required to complete the sutures, and the amplitude and the frequency of physiological tremor during the suturing. In addition, we used a four-point ordinal scale to rank the quality of the sutures for each task. Each participant repeated the tasks several times on separate days varying the pre-task alcohol consumption (including one sober task at the end of the data collection).ResultsA total of 93 surgical tasks (47 macrosurgical, 46 microsurgical) were performed. The fastest microsurgical suturing (median 11 min 49 s, [interquartile range (IQR) 654 to 761 s]) was recorded after three doses of alcohol (median blood alcohol level 0.32‰). The slowest microsurgical suturing (median 15 min 19 s, [IQR 666 to 1121 s]) was observed after one dose (median blood alcohol level 0‰). The quality of sutures was the worst (mean 0.70 [standard deviation (SD) 0.48] quality points lost) after three doses of alcohol and the best (mean 0.33 [SD 0.52] quality points lost) after four doses (median blood alcohol level 0.44‰).ConclusionsConsuming small amount of alcohol did not deteriorate microsurgical performance in our study. An observed reduction in physiological tremor may partially explain this.

Utilizing Grasp Monitoring to Predict Microsurgical Expertise

IntroductionMost microsurgical procedures require the surgeon to use tools to grasp and hold fragile objects in the surgical site. Prior research on grasping in surgery has mostly either been in other surgical techniques or used grasping as an auxiliary metric. We focus on microsurgery and investigate what grasping can tell about microsurgical skill and suturing performance. This study lays groundwork for using automatic detection of grasps to evaluate surgical skill. MethodsFive expert surgeons and six novices completed sutures on a microsurgical training board. Video recordings of the performance were annotated for the number of grasps, while an eye tracker recorded the participants’ pupil dilations for cognitive workload assessment. Performance was measured with suturing duration and the University of Western Ontario Microsurgical Skills Assessment instrument (UWOMSA). Differences in skill, suturing performance and cognitive workload were compared with grasping behavior. ResultsNovices needed significantly more grasps to complete sutures and failed to grasp more often than the experts. The number of grasps affected the suturing duration more in novices. Decreasing suturing efficiency as measured by UWOMSA instrument was associated with increase in grasps, even when we controlled for overall skill differences. Novices displayed larger pupil dilations when averaged over a sufficiently large sample, and the difference increased after the grasp. ConclusionsGrasping action during microsurgical procedures can be used as a conceptually simple yet objective proxy in microsurgical performance assessment. If the grasps could be detected automatically, they could be used to aid in computational evaluation of surgical trainees’ performance.

Video-Based Microsurgical Education versus Stationary Basic Microsurgical Course: A Noninferiority Randomized Controlled Study.

Repetitive training is essential for microsurgical performance. This study aimed to compare the improvement in basic microsurgical skills using two learning methods: stationary microsurgical course with tutor supervision and self-learning based on digital instructional materials. We hypothesized that video-based training provides noninferior improvement in basic microsurgical skills. In this prospective study, 80 participants with no prior microsurgical experience were randomly divided into two groups: the control group, trained under the supervision of a microsurgical tutor, and the intervention group, where knowledge was based on commonly available online instructional videos without tutor supervision. Three blinded expert microsurgeons evaluated the improvement in basic microsurgical skills in both groups. The evaluation included an end-to-end anastomosis test using the Ten-Point Microsurgical Anastomosis Rating Scale (MARS10) and a six-stitch test on a latex glove. Statistically significant differences between groups were identified using standard noninferiority analysis, chi-square, and t-tests. Seventy-seven participants completed the course. Baseline test scores did not differ significantly between groups. After the 4-day microsurgical course, both groups showed statistically significant improvement in microsurgical skills measured using the MARS10. The performed tests showed that data for self-learning using digital resources provides noninferior data for course with surpervision on the initial stage of microsurgical training (7.84; standard deviation [SD], 1.92; 95% confidence interval [CI], 7.25-8.44) to (7.72; SD, 2.09; 95% CI, 7.07-8.36). Video-based microsurgical training on its initial step provides noninferior improvement in microsurgical skills to training with a dedicated instructor.

An Analysis of the Effect of selected Factors on microsurgical Performance.

Microsurgery is a specific surgical expertise that involves operating on very small structures, and requires the assistance of a magnifying device: a microscope or loupes. Several factors have been identified that could affect the quality of microsurgical performance in training or surgical procedures. The objective of this study was to assess the impact of the selected factors - caffeine, alcohol and physical exercise - on a microsurgical task prior its performance. Ten students from the 5th and 6th years of medical studies who had completed the advanced microsurgical course performed a "6-stitches test" on a latex glove spanned over a cup prior to and after consumption of caffeine, alcohol and performing physical exercises. The times taken to complete the task at baseline and post-exposure were recorded. The results of the study show a statistically significant positive effect of caffeine and a statistically significant negative effect of physical exercise on microsurgical performance when performed shortly before the task. Small dose of alcohol taken before the task showed had little effect on performance.

Microsurgical Anastomosis Rating Scale (MARS10): A Final Product Scoring System for Initial Microsurgical Training.

High cost and ethical controversy of using living models in microsurgical training made non-living models more popular. However, non-living models don't provide appropriate feedback of microsurgical performance. Currently existing Global Rating Scales used for advanced microsurgical skills validation are difficult to apply on non-living model. This study presents a simple instrument for basic assessment of microsurgical anastomosis on non-living model. Seventy medical students were divided into 2 groups depending on their prior microsurgical experience. Each participant performed 3 end-to-end anastomoses on chicken femoral artery model. Anastomoses were reviewed by 3 blinded experts and then photographed. Evaluation included a patency tests, longitudinal cut of anastomosis, and the newly proposed tool 10 Point Microsurgical Anastomosis Rating Scale (MARS10). Presented scale consists of 5 factors important for anastomosis closure (anastomosis closure, suture spacing, bites size, knot tying, and cut ends length), graded on 3 point scale (0-2 points). Results were analyzed with analysis of variance, Spearman correlation, and t Student test. Anastomoses evaluated by experts as patent significantly correlated with a high summary score in MARS10 scale (r = 0.73 P < .0001). There was a significant difference in MARS10 score between groups (P < .0001). There were no significant inter-rater differences in scoring among all 3 evaluators (p > .05). 10 Point Microsurgical Anastomosis Rating Scale is a quick, valid, and reliable tool to assess microsurgical end-to-end arterial anastomoses on non-living model.

Association of Weight-Adjusted Caffeine and β-Blocker Use With Ophthalmology Fellow Performance During Simulated Vitreoretinal Microsurgery

Vitreoretinal surgery can be technically challenging and is limited by physiologic characteristics of the surgeon. Factors that improve accuracy and precision of the vitreoretinal surgeon are invaluable to surgical performance. To establish weight-adjusted cutoffs for caffeine and β-blocker (propranolol) intake and to determine their interactions in association with the performance of novice vitreoretinal microsurgeons. This single-blind cross-sectional study of 15 vitreoretinal surgeons who had less than 2 years of surgical experience was conducted from September 19, 2018, to September 25, 2019, at a dry-laboratory setting. Five simulations were performed daily for 2 days. On day 1, performance was assessed after sequential exposure to placebo, low-dose caffeine (2.5 mg/kg), high-dose caffeine (5.0 mg/kg), and high-dose propranolol (0.6 mg/kg). On day 2, performance was assessed after sequential exposure to placebo, low-dose propranolol (0.2 mg/kg), high-dose propranolol (0.6 mg/kg), and high-dose caffeine (5.0 mg/kg). Surgical simulation tasks were repeated 30 minutes after masked ingestion of placebo, caffeine, or propranolol pills during the 2 days. An Eyesi surgical simulator was used to assess surgical performance, which included surgical score (range, 0 [worst] to 700 [best]), task completion time, intraocular trajectory, and tremor rate (range, 0 [worst] to 100 [best]). The nonparametric Friedman test followed by Dunn-Bonferroni post hoc test was applied for multiple comparisons. Of 15 vitreoretinal surgeons, 9 (60%) were male, with a mean (SD) age of 29.6 (1.4) years and mean (SD) body mass index (calculated as weight in kilograms divided by height in meters squared) of 23.15 (2.9). Compared with low-dose propranolol, low-dose caffeine was associated with a worse total surgical score (557.0 vs 617.0; difference, -53.0; 95% CI, -99.3 to -6.7; P = .009), a lower antitremor maneuver score (55.0 vs 75.0; difference, -12.0; 95% CI, -21.2 to -2.8; P = .009), longer intraocular trajectory (2298.6 vs 2080.7 mm; difference, 179.3 mm; 95% CI, 1.2-357.3 mm; P = .048), and increased task completion time (14.9 minutes vs 12.7 minutes; difference, 2.3 minutes; 95% CI, 0.8-3.8 minutes; P = .048). Postcaffeine treatment with propranolol was associated with performance improvement; however, surgical performance remained inferior compared with low-dose propranolol alone for total surgical score (570.0 vs 617.0; difference, -51.0; 95% CI, -77.6 to -24.4; P = .01), tremor-specific score (50.0 vs 75.0; difference, -16.0; 95% CI, -31.8 to -0.2; P = .03), and intraocular trajectory (2265.9 mm vs 2080.7 mm; difference, 166.8 mm; 95% CI, 64.1-269.6 mm; P = .03). The findings suggest that performance of novice vitreoretinal surgeons was worse after receiving low-dose caffeine alone but improved after receiving low-dose propranolol alone. Their performance after receiving propranolol alone was better than after the combination of propranolol and caffeine. These results may be helpful for novice vitreoretinal surgeons to improve microsurgical performance.

Influence of stereopsis on the ability to perform simulated microsurgery.

To determine whether impaired or absent stereopsis affects the ability to perform simulated microsurgical tasks. University of Edinburgh, United Kingdom. Prospective randomized cross-over study. Visual acuity and stereoacuity were measured. A band-pass filter was placed over the nondominant eye to reduce stereoacuity to 150 seconds of an arc (partial stereopsis), or the nondominant eye was completely occluded (absent stereopsis). Participants completed a computerized surgical simulator task 3 times with a randomized testing order (normal stereopsis, absent stereopsis, and partial stereopsis). The task involved using forceps to grasp and position objects in the anterior chamber. Outcomes included area of ocular injury, time to task completion, and overall score. Ocular damage area was significantly worse with partial stereopsis (P = .002) and worse still when stereopsis was absent (P < .001 for normal vs absent stereopsis and P = .005 for partial vs absent stereopsis). The median ocular damage area was 3.55 mm (interquartile range [IQR], 1.21-5.88 mm) with normal stereopsis, increasing to 6.10 mm (IQR, 3.96-12.47 mm) with stereopsis reduced to 150 seconds of an arc and to 9.25 mm (IQR, 4.93-18.70 mm) with no stereopsis. Time taken to complete the task increased and overall score decreased as stereopsis was reduced. The overall score decreased from 53% (IQR, 22.5-82%) under normal stereopsis to 0% (IQR, 0-43.5%) with absent stereopsis. Impaired stereopsis was associated with worse microsurgical performance, which may have implications for surgical training. The absence of stereopsis resulted in worse performance than partial reduction in stereopsis.

Determining the Effect of External Stressors and Cognitive Distraction on Microsurgical Skills and Performance.

Introduction: Microsurgery is an essential element of Plastic Surgery practice. There is a paucity of studies assessing the impact of stress and cognitive distraction on technical microsurgical performance. The ability to complete cognitive and technical skills in parallel has not been assessed in a microsurgical setting.Aim: To test the hypothesis that cognitive distraction and external stressors negatively affect microsurgical performance in a high fidelity simulation setting.Materials/Methods: Fourteen surgeons across all levels of training undertook 2 microsurgical skills sessions, 1 month apart. Session one established baseline microsurgical skill. In session two, skills were assessed with the introduction of realistic operative room cognitive distractions (ORDIs). Outcome measures were efficiency and accuracy, measured by Time to Completion (TTC) and Anastomosis Lapse Index (ALI), respectively.Key Results: Fourteen participants (6 novices, 5 plastic surgery specialist trainees and 3 consultants) completed both microsurgical skills sessions. In total, 28-microvascular anastomosis were analyzed. Mean baseline TTC for the group was 20.36 min. With cognitive distraction and external stress mean TTC decreased to 17.87 min. Mean baseline ALI score for the group was 3.32 errors per anastomosis. The introduction of cognitive distraction and external stress increased the mean to 4.86 errors per anastomosis. Total errors per anastomosis increased from 91 errors at baseline to 137 errors with cognitive distraction and external stress. Under stress, participants were more efficient but had reduced anastomotic accuracy.Conclusion: Under stress, surgeons were more efficient, this translated into faster completion of a microsurgical anastomosis. Efficiency, however, came at the expense of accuracy.

The Influence of stereopsis on ability to perform simulated cataract surgery

AbstractBackgroundThe purpose of this study was to determine whether impaired or absent stereopsis affects ability to perform simulated microsurgical tasks.MethodsA prospective randomized cross‐over study including 12 medical students. Visual acuity and stereoacuity were measured for all subjects. A band pass filter was placed over the non‐dominant eye to reduce stereoacuity to 150 seconds of an arc (partial stereopsis) or the non‐dominant eye was completely occluded (absent stereopsis). Participants completed a computerized surgical simulator task three times with the order of testing randomized (normal stereopsis, absent stereopsis and partial stereopsis). The task involved forceps to grasp and position objects in the anterior chamber. Outcomes included area of ocular injury, time to task completion and overall score.ResultsOcular damage area was significantly worse when stereopsis was impaired to 150 seconds of an arc (p = 0.002), and worse still when stereopsis was absent (p &lt; 0.001 for normal versus absent stereopsis and p = 0.005 for impaired versus absent stereopsis). The median ocular damage area was 3.55 mm2 (IQ range 1.21 to 5.88 mm2) with normal stereopsis, increasing to 6.10 mm2 (IQ range 3.96 to 12.47 mm2) with stereopsis reduced to 150 seconds of an arc and to 9.25 mm2 (IQ range 4.93 to 18.70 mm2) with no stereopsis. Time taken to complete the task increased and overall score decreased as stereopsis was reduced. Overall score decreased from 53% (IQ range 22.5 to 82%) under normal stereopsis to 0% (0 to 43.5%) with absent stereopsis.ConclusionImpaired stereopsis was associated with worse microsurgical performance which may have implications for surgical training. Absence of stereopsis resulted in worse performance than partial reduction in stereopsis.

P56 Virtual reality simulation in neurosurgical training: a single blinded randomised controlled trial &amp; review of all available training models

ObjectivesVirtual reality (VR) simulators are one of the training models allowing the practice of surgical skills for trainees. We aim to assess the benefit of VR training in neurosurgery.DesignA single-blinded randomised controlled trial and a literature review.SubjectsTrainees (n=12), Fellows and Consultant Neurosurgeons (n=4) and Medical Students (n=6) with no experience of VR.MethodsParticipants were randomised according to their grades. Both groups completed microsurgical tasks and duration and quality of each task was recorded at the start and the endpoint of the study. Questionnaires were used to assess the participants’ confidence in microsurgical skills. The intervention group underwent structured training using a VR simulator (NeuroVR). The primary outcome measure was microsurgical performance assessed by three independent assessors blinded to trainee status. The secondary outcome measure was performance time and confidence levels.ResultsObserved improvements in the primary outcome were not significant. The performance time in the intervention group improved significantly with a mean difference of 79.8 s (8–178 s) (p&lt;0.05). The intervention group reported significantly improved confidence levels in all microsurgical skills (8.8%, p&lt;0.001). Less experienced trainees had the greatest reductions in time and improved confidence levels.ConclusionsVR training in neurosurgery, particularly in less experienced trainees, can prove useful. Future studies should assess the effect of VR training on clinical procedures.

Depth-Based, Motion-Stabilized Colorization of Microscope-Integrated Optical Coherence Tomography Volumes for Microscope-Independent Microsurgery.

PurposeWe develop and assess the impact of depth-based, motion-stabilized colorization (color) of microscope-integrated optical coherence tomography (MIOCT) volumes on microsurgical performance and ability to interpret surgical volumes.MethodsColor was applied in real-time as gradients indicating axial position and stabilized based on calculated center of mass. In a test comparing colorization versus grayscale visualizations of prerecorded intraoperative volumes from human surgery, ophthalmologists (N = 7) were asked to identify retinal membranes, the presence of an instrument, its contact with tissue, and associated deformation of the retina. In a separate controlled trial, trainees (N = 15) performed microsurgical skills without conventional optical visualization and compared colorized versus grayscale MIOCT visualization on a stereoptic screen. Skills included thickness identification, instrument placement, and object manipulation, and were assessed based on time, performance metrics, and confidence.ResultsIn intraoperative volume testing, colorization improved ability to differentiate membrane from retina (P < 0.01), correctly identify instrument contact with membrane (P = 0.03), and retinal deformation (P = 0.01). In model microsurgical skills testing, trainees working with colorized volumes were faster (P < 0.01) and more correct (P < 0.01) in assessments of thickness for recessed and elevated objects, were less likely to inadvertently contact a surface when approaching with an instrument (P < 0.01), and uniformly more confident (P < 0.01 for each) in conducting each skill.ConclusionsDepth-based colorization enables effective identification of retinal membranes and tissue deformation. In microsurgical skill testing, it improves user efficiency, and confidence in microscope-independent, OCT-guided model surgical maneuvers.Translational RelevanceNovel depth-based colorization and stabilization technology improves the use of intraoperative MIOCT.

Systematic Review of Factors Influencing Surgical Performance: Practical Recommendations for Microsurgical Procedures in Neurosurgery.

Microneurosurgical techniques involve complex manual skills and hand-eye coordination that require substantial training. Many factors affect microneurosurgical skills. The goal of this study was to use a systematic evidence-based approach to analyze the quality of evidence for intrinsic and extrinsic factors that influence microneurosurgical performance and to make weighted practical recommendations. A literature search of factors that may affect microsurgical performance was conducted using PubMed and Embase. The criteria for inclusion were established in accordance with the PRISMA-P (Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols) statement. Forty-eight studies were included in the analysis. Most of the studies used surgeons as participants. Most used endoscopic surgery simulators to assess skills, and only 12 studies focused on microsurgery. This review provides 18 practical recommendations based on a systematic literature analysis of the following 8 domains: 1) listening to music before and during microsurgery, 2) caffeine consumption, 3) β-blocker use, 4) physical exercise, 5) sleep deprivation, 6) alcohol consumption before performing surgery, 7) duration of the operation, and 8) the ergonomic position of the surgeon. Despite the clear value of determining the effects of various factors on surgical performance, the available body of literature is limited, and it is not possible to determine standards for each surgical field. These recommendations may be used by neurosurgical trainees and practicing neurosurgeons to improve microsurgical performance and acquisition of microsurgical skills. Randomized studies assessing the factors that influence microsurgical performance are required.

Factors Correlating With Microsurgical Performance: A Clinical and Experimental Study

Microsurgery is one the most complex surgical skills to master. The factors correlating with microsurgical performance, however, are poorly understood. Understanding these factors will aid in the training and assessment of microsurgeons. A total of 29 microsurgery fellows enrolled in a dedicated 1-year microsurgery fellowship were included in the study. For the clinical evaluations, microsurgical anastomosis performance was evaluated during multiple procedures in the operating room at the start, midpoint, and end of the fellowship by all departmental faculty using a validated microsurgical assessment tool. For the laboratory evaluations, blinded video recordings of each fellow performing an arterial femoral anastomosis in a live rat model at the start and end of the fellowship were evaluated using 3 validated microsurgical global ratings scale tools. Correlations between performance and the factors assessed by the tools were evaluated. In the clinical study there were a total of 474 anastomosis evaluations; clinical performance correlated best with speed, instrument handling, and motion. In the laboratory study 58 evaluations were conducted, and performance tracked most closely with instrument handling, flow of operation, and operative steps, as well as correlating significantly inversely with time taken. The most common errors committed were unequal stitch bites, wrong grasp/damage tissue, and loose knot. Speed, both subjective and objective, instrument handling, operative flow, and motion, were relevant to performance of a microsurgical anastomosis. A prospective trial is now necessary to determine whether these factors should be considered in definitions of competency in microsurgery training pathways.

Interview Scores Correlate with Fellow Microsurgical Skill and Performance

The interview process for surgical trainees aims to select those individuals who will perform best during training and have the greatest potential as future surgeons. The objective of this study was to evaluate the relationship between criteria assessed at interview, technical skills, and performance, for the first time, to optimize the selection process for a Microsurgery fellowship. Twenty microsurgery fellows in three consecutive annual cohorts at a single academic center were prospectively evaluated. At interview, subjects were scored for multiple standardized domains. At the start and at end of the fellowship, microsurgical technical skill was assessed both in the laboratory and operating room (OR) using a validated assessment tool. At the end of the fellowship, there was a final evaluation of performance. At the start, microsurgical skill significantly correlated with almost all domains evaluated at interview, most closely with prior plastic surgery training experience. At the end of the fellowship, skill level improved in all trainees, with the greatest improvement made by the lowest ranked and skilled trainees. The highest ranked trainees, however, made the greatest improvement in speed. The results of this study, for the first time, validate the current interview process to correctly select the highest performing and most skilled candidates and support the effectiveness of a 1-year microsurgical fellowship in improving microsurgical skill in all trainees, irrespective of their initial ability. The importance of valuing the relative quality of prior training and experience at selection is also highlighted.

Easy, Efficient, and Mobile Way to Train Microsurgical Skills During Busy Life of Neurosurgical Residency in Resource-Challenged Environment.

Residents' lives are hectic-it is hard to find a place and time for training basic and advanced microsurgical skills. Surgical instruments and sutures can be purchased (or loaned from another department), but the most expensive and space-occupying device is the microscope. In developing countries, microscopes are used where they are needed most, in operating rooms. Furthermore, a conventional microscope is not portable. For all of these reasons, the availability of microscopes for training microsurgery is limited. We used a coffee cup and smartphone (CCS) as a training device instead of a microscope. The coffee cup was the base, and the smartphone functioned to magnify, illuminate, and visualize objects. We measured 2 residents' performance on end-to-end artificial bypass before and after 5 days of CCS-based training. We were able to quickly set up the environment for practicing microsurgical skills in any surrounding. After 5 days of training with CCS we could see significant development of microsurgical performance with a conventional microscope as well. The learning curve was dependent on baseline performance. CCS is efficient, mobile, and easy to set up. Even though our smartphone-based training was in 2 dimensions, we could improve our microsurgical performance with conventional microscopes, which have 3-dimensional capability. CCS also provides an easy method to record one's microsurgical training. CCS improved both of the subjects' microsurgical performance, making it a good alternative for a traditional microscope.