Robotics-Assisted Surgical Skills Evaluation based on Electrocortical Activity.

Skills assessment in Robotics-Assisted Minimally Invasive Surgery (RAMIS) is mainly performed based on temporal, motion-based and outcome-based metrics. While these components are essential for the proper assessment of skills in RAMIS, they do not suffice for full representation of all underlying aspects of skilled performance. Besides such commonplace components of skills, there exist other elements to be taken into account for comprehensive skills assessment. Among such elements are cognitive states (such as levels of stress, attention, concentration) that can directly affect performance. Investigating the impact of electrocortical activity and cognitive states of RAMIS surgeons over their performance has, however, received little attention in the literature. Therefore, in this paper, novel performance metrics based on electroencephalography (EEG) signals are studied for potential augmentation into RAMIS training and its assessment platform. For this purpose, a user study was conducted involving 23 novices and 9 expert RAMIS surgeons. The participants were asked to perform two tasks on the dv-Trainer®, (Mimic Technologies) RAMIS simulator, while their brain EEG signals were being measured using the Muse EEG headband (InteraXon Inc.). The performance metrics were defined as mean values of band powers of EEG signals over various ranges of frequency. Statistical analysis was performed to evaluate metrics over 5 different ranges of frequency for 4 electrode locations and during 2 RAMIS training tasks. The results indicated statistically significant differences in electrocortical activity between novices and experts in temporoparietal and left frontal regions of their brain for mid to high-frequency ranges. Overall, RAMIS experts showed lower levels of electrocortical activity in those regions compared to novices. The results indicate that electrocortical activity measured by EEG signals have the potential to provide useful information for skills assessment in RAMIS.

Mastery Learning - does the method of learning make a difference in skills acquisition for robotic surgery?

BACKGROUND: Few studies compare the effectiveness of blocked vs random practice conditions in minimally invasive surgery training, and none have evaluated these in robotic surgery training. METHODS: The dV-Trainer® and the da Vinci® Surgical System (dVSS) were used to compare practice conditions. Forty-two participants were randomized into blocked and random practice groups. Each participant performed five tasks: Ring Walk, Thread the Rings, Needle Targeting, Suture Sponge and Tubes Level 2. Transfer to the dVSS was also assessed. RESULTS: No significant differences were observed between the two groups, except for a few instances. For example, during Ring Walk, the random group performed significantly faster than the blocked group (100.78 ± 5.26 s vs 121.59 ± 5.26 s, p < 0.01). CONCLUSIONS: The study results do not follow the current evidence presented in the education literature. This is the first time that blocked versus random practice was tested for robotic surgery training.

Catheter based selective hypothermia reduces stroke volume during focal cerebral ischemia in swine.

BACKGROUND: Total body hypothermia is an established neuroprotectant in global cerebral ischemia. The role of hypothermia in acute ischemic stroke remains uncertain. Selective application of hypothermia to a region of focal ischemia may provide similar protection with more rapid cooling and elimination of systemic side effects. We studied the effect of selective endovascular cooling in a focal stroke model in adult domestic swine. METHODS: After craniotomy under general anesthesia, a proximal middle cerebral artery branch was occluded for 3 h, followed by 3 h of reperfusion. In half of the animals, selective hypothermia was induced during reperfusion using a dual lumen balloon occlusion catheter placed in the ipsilateral common carotid artery. Following reperfusion, the animals were sacrificed. Brain MRI and histology were evaluated by experts who were blinded to the intervention. RESULTS: 25 animals were available for analysis. Using selective hypothermia, hemicranial temperature was successfully cooled to a mean of 26.5 °C. Average time from start of perfusion to attainment of moderate hypothermia (<30 °C) was 25 min. Mean MRI stroke volumes were significantly reduced by selective cooling (0.050±0.059 control, 0.005±0.011 hypothermia (ratio stroke:hemisphere volume) (p=0.046). Stroke pathology volumes were reduced by 42% compared with controls (p=0.256). CONCLUSIONS: Selective moderate hypothermia was rapidly induced using endovascular techniques in a clinically realistic swine stroke model. A significant reduction in stroke volume on MRI was observed. Endovascular selective hypothermia can provide neuroprotection within time frames relevant to acute ischemic stroke treatment.

Randomized control trial for evaluation of a hands-free pointer for surgical instruction during laparoscopic cholecystectomy.

INTRODUCTION: Training surgeons in minimally invasive surgery (MIS) requires surgical residents to operate under the direction of a consultant. The inability of the instructing surgeon to point at the laparoscopic monitor without releasing the instruments remains a barrier to effective instruction. The wireless hands-free surgical pointer (WHaSP) has been developed to aid instruction during MIS. METHODS: The objective of this study was to evaluate the effectiveness and likeability of the WHaSP as an instructional tool compared with the conventional methods. Data were successfully collected during 103 laparoscopic cholecystectomy procedures, which had been randomized to use or not use the WHaSP as a teaching tool. Audio and video from the surgeries were recorded and analyzed. Instructing surgeons, operating surgeons, and camera assistants provided feedback through a post-operative questionnaire that used a five-level Likert scale. The questionnaire results were analyzed using a Mann-Whitney U test. RESULTS: There were no negative effects on surgery completion time or instruction practice due to the use of the WHaSP. The number of times an instructor surgeon pointed to the laparoscopic screen with their hand was significantly reduced when the WHaSP was utilized (p < 0.001). The questionnaires showed that WHaSP users found it to be comfortable, easy to use, and easy to control. Compared to when the WHaSP was not used, users found that communication was more effective (p = 0.002), locations were easier to communicate (p < 0.001), and instructions were easier to follow (p = 0.005). CONCLUSIONS: The WHaSP system was successfully used in surgery. It integrated seamlessly into existing equipment within the operating room and did not affect flow. The positive outcomes of utilizing the WHaSP were improved communication in the OR, improved efficiency and safety of the surgery, easy to use, and comfortable to wear. The surgeons showed a preference for utilizing the WHaSP if given a choice.