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Objective: Cemented total hip arthroplasty (THA) demonstrates superior survival rates compared to uncemented procedures. Nevertheless, most younger patients opt for uncemented THA, as removing well-fixed bone cement in the femur during revisions is complex, particularly the distal cement plug. This removal procedure often increases the risk of femoral fracture or perforation, haemorrhage and weakening bone due to poor drill control and positioning. Aim of this study was to design a novel drill guide to improve drill positioning. Methods and procedures: A novel orthopaedic drill guide was developed, featuring a compliant centralizer activated by a drill guide actuator. Bone models were prepared to assess centralizing performance. Three conditions were tested: drilling without guidance, guided drilling with centralizer activation held, and guided drilling with centralizer activation released. Deviations from the bone centre were measured at the entry and exit point of the drill. Results: In the centralizing performance test, the drill guide significantly reduced drill hole deviations in both entry and exit points compared to the control (p < 0.05). The absolute deviation on the exit side of the cement plug was 10.59mm (SD 1.56) for the 'No drill guide' condition, 3.02mm (SD 2.09) for 'Drill guide - hold' and 2.12mm (SD 1.71) for 'Drill guide - release'. The compliant drill guide centralizer significantly lowered the risk of cortical bone perforation during intramedullary canal drilling in the bone models due to better control of the cement drill position. Clinical and Translational Impact Statement: The drill guide potentially reduces perioperative risks in cemented femoral stem revision. Future research should identify optimal scenarios for its application., Medical Instruments & Bio-Inspired Technology

Collision feedback about instrument and environment interaction is often lacking in robotic surgery training devices. The PoLaRS virtual reality simulator is a newly developed desk trainer that overcomes drawbacks of existing robot trainers for advanced laparoscopy. This study aimed to assess the effect of haptic and visual feedback during training on the performance of a robotic surgical task. Robotic surgery-naïve participants were randomized and equally divided into two training groups: Haptic and Visual Feedback (HVF) and No Haptic and Visual Feedback. Participants performed two basic virtual reality training tasks on the PoLaRS system as a pre- and post-test. The measurement parameters Time, Tip-to-tip distance, Path length Left/Right and Collisions Left/Right were used to analyze the learning curves and statistically compare the pre- and post-tests performances. In total, 198 trials performed by 22 participants were included. The visual and haptic feedback did not negatively influence the time to complete the tasks. Although no improvement in skill was observed between pre- and post-tests, the mean rank of the number of collisions of the right grasper (dominant hand) was significantly lower in the HVF feedback group during the second post-test (Mean Rank = 8.73 versus Mean Rank = 14.27, U = 30.00, p = 0.045). Haptic and visual feedback during the training on the PoLaRS system resulted in fewer instrument collisions. These results warrant the introduction of haptic feedback in subjects with no experience in robotic surgery. The PoLaRS system can be utilized to remotely optimize instrument handling before commencing robotic surgery in the operating room., Biomechanical Engineering, Medical Instruments & Bio-Inspired Technology

Introduction: Most robotic instruments and their drives still risk residual contamination due to cleaning complexities, rendering them limited reusable, and tend to have larger instruments than the 5mm laparoscopic standard. The novel steerable laparoscopic SATA-LRS uses modularity for cleanability and exchangeability. The SATA-Drive: a robotic driver designed for the actuation of a 3mm scaled version of the SATA-LRS is presented. Methods: A modular, expandable gear mechanism was designed to efficiently rotate and translate the instrument shafts. The 3mm SATA-LRS is controlled as proof. An user-experiment is conducted to test the (de)coupling of the instrument to and from the drive. Results: A video shows the SATA-Driver successfully articulating, rotating and grasping the end-effector. End-effector dis- and reassembly is possible in 36 (13 SD) seconds, while complete instrument coupling requires 28(8 SD) seconds and de-coupling requires 16 (7 SD) seconds. Discussion: A non-surgical robot arm, mounted with the SATA-drive has effectively been transformed into a system similar to robot assisted laparoscopy. The modularity of the drive's segmented build can easily be adapted and could benefit the adoption of future instruments. The SATA-LRS's cleanability features and its end-effector changes without disassembly are expected to benefit medical robotics. The 3mm SATA-LRS shows the instrument's potential for mini-laparoscopy., Medical Instruments & Bio-Inspired Technology

Background: Compliance with the recommended 30 s drying time of alcohol-based hand rub (ABHR) is often suboptimal. To increase hand hygiene compliance at a neonatal intensive care unit (NICU), we installed an Incubator Traffic Light (ITL) system which shows ‘green light’ to open incubator doors after the recommended drying time. Aim: To measure the impact of this visual feedback system on NICU healthcare professionals' compliance with the recommended ABHR drying time. Methods: Ten traffic light systems were installed on incubators at a NICU, five of which provided visual feedback, and five, serving as a control group, did not provide visual feedback. During a two-month period, the systems measured drying time between the moment of dispensing ABHR and opening the incubator's doors. The drying times of the incubators were compared with and without feedback. Findings: Of the 6422 recorded hand hygiene events, 658 were valid for data analysis. Compliance with correct drying time reached 75% (N = 397/526) for incubators equipped with visual feedback versus 36% (N = 48/132; P < 0.0001) for incubators lacking this feature. Conclusion: The ITL improves compliance with the recommended 30 s ABHR drying time in a NICU setting., Medical Instruments & Bio-Inspired Technology

Introduction: In clinical practice, fetal heart rate monitoring is performed intermittently using Doppler ultrasound, typically for 30 minutes. In case of a non-reassuring heart rate pattern, monitoring is usually prolonged. Noninvasive fetal electrocardiography may be more suitable for prolonged monitoring due to improved patient comfort and signal quality. This study evaluates the performance and patient experience of four noninvasive electrocardiography devices to assess candidate devices for prolonged noninvasive fetal heart rate monitoring. Material and methods: Non-critically sick women with a singleton pregnancy from 24 weeks of gestation were eligible for inclusion. Fetal heart rate monitoring was performed during standard care with a Doppler ultrasound device (Philips Avalon-FM30) alone or with this Doppler ultrasound device simultaneously with one of four noninvasive electrocardiography devices (Nemo Fetal Monitoring System, Philips Avalon-Beltless, Demcon Dipha-16 and Dräger Infinity-M300). Performance was evaluated by: success rate, positive percent agreement, bias, 95% limits of agreement, regression line, root mean square error and visual agreement using FIGO guidelines. Patient experience was captured using a self-made questionnaire. Results: A total of 10 women were included per device. For fetal heart rate, Nemo performed best (success rate: 99.4%, positive percent agreement: 94.2%, root mean square error 5.1 BPM, bias: 0.5 BPM, 95% limits of agreement: −9.7 – 10.7 BPM, regression line: y = −0.1x + 11.1) and the cardiotocography tracings obtained simultaneously by Nemo and Avalon-FM30 received the same FIGO classification. Comparable results were found with the Avalon-Beltless from 36 weeks of gestation, whereas the Dipha-16 and Infinity-M300 performed significantly worse. The Avalon-Beltless, Nemo and Infinity-M300 closely matched the performance of the Avalon-FM30 for maternal heart rate, whereas the performance of the Dipha-16 deviated more. P, Medical Instruments & Bio-Inspired Technology

Background: The steep radiation dose gradients in cervical cancer brachytherapy (BT) necessitate a thorough understanding of the behavior of afterloader source cables or needles in the curved channels of (patient-tailored) applicators. Purpose: The purpose of this study is to develop and validate computer models to simulate: (1) BT source positions, and (2) insertion forces of needles in curved applicator channels. The methodology presented can be used to improve the knowledge of instrument behavior in current applicators and aid the development of novel (3D-printed) BT applicators. Methods: For the computer models, BT instruments were discretized in finite elements. Simulations were performed in SPACAR by formulating nodal contact force and motion input models and specifying the instruments’ kinematic and dynamic properties. To evaluate the source cable model, simulated source paths in ring applicators were compared with manufacturer-measured source paths. The impact of discrepancies on the dosimetry was estimated for standard plans. To validate needle models, simulated needle insertion forces in curved channels with varying curvature, torsion, and clearance, were compared with force measurements in dedicated 3D-printed templates. Results: Comparison of simulated with manufacturer-measured source positions showed 0.5–1.2 mm median and <2.0 mm maximum differences, in all but one applicator geometry. The resulting maximum relative dose differences at the lateral surface and at 5 mm depth were 5.5% and 4.7%, respectively. Simulated insertion forces for BT needles in curved channels accurately resembled the forces experimentally obtained by including experimental uncertainties in the simulation. Conclusion: The models developed can accurately predict source positions and insertion forces in BT applicators. Insights from these models can aid novel applicator design with improved motion and force transmission of BT instruments, and contribute to the estimation of o, Medical Instruments & Bio-Inspired Technology, Mechatronic Systems Design

While articulated surgical instruments have enabled the proliferation of minimally invasive interventions, procedures such as laparo-endoscopic single-site surgery are waning in popularity. One potential reason for this decline is a lack of sufficiently dexterous instruments. Although multi-steerable instruments exist, these are often complex and therefore expensive assemblies. Even when 3D printing was used to simplify the design of these instruments, the requirement for high-performance 3D printers limited the reduction in manufacturing costs. To tackle this issue, we propose six guidelines for converting a 3D printed compliant medical instrument from printing on a Digital Light Processing (DLP) printer to a Fused Filament Fabrication (FFF) printer. These guidelines provide a framework to manage and compensate for differences in the two processes to achieve comparable results at a reduced cost. The proposed guidelines were evaluated by assembling a FFF 3D printed prototype that shows equivalent performance to its DLP 3D printed counterpart., Medical Instruments & Bio-Inspired Technology

Minimally Invasive Procedures (MIPs) emerged as an alternative to more invasive surgical approaches, offering patient benefits such as smaller incisions, less pain, and shorter hospital stay. In one class of MIPs, where natural body lumens or small incisions are used to access deeper anatomical locations, Flexible Surgical and Interventional Robots (FSIRs) such as catheters and endoscopes are widely used. Due to their flexible and compliant nature, FSIRs can be inserted via natural orifices or small incisions, then moved towards hard-to-reach targets to perform interventional tasks. However, existing FSIRs are confronted with challenges in sensing, control, and navigation. These issues stem from the robot's non-linear behavior and the intricate nature of the lumens, where accurately modeling the complex interactions and disturbances proves to be exceptionally difficult. The rapid advances in Machine Learning (ML) have facilitated the widespread adoption of ML techniques in FSIRs. This article provides an overview of these efforts by first introducing a classification of existing ML algorithms, including traditional ML methods and modern Deep Learning (DL) approaches, commonly used in FSIRs. Next, the use of ML algorithms is surveyed per sub-domain, namely for perception, modeling, control, and navigation. Trends, popularity, strengths, and/or limitations of different ML algorithms are analyzed. The different roles that ML plays among tasks are investigated and described. Finally, discussions are conducted on the limitations and the prospects of ML in MIPs., Medical Instruments & Bio-Inspired Technology, Human-Robot Interaction, Learning & Autonomous Control

Background: Compliance with the recommended 30 s drying time of alcohol-based hand rub (ABHR) is often suboptimal. To increase hand hygiene compliance at a neonatal intensive care unit (NICU), we installed an Incubator Traffic Light (ITL) system which shows ‘green light’ to open incubator doors after the recommended drying time. Aim: To measure the impact of this visual feedback system on NICU healthcare professionals' compliance with the recommended ABHR drying time. Methods: Ten traffic light systems were installed on incubators at a NICU, five of which provided visual feedback, and five, serving as a control group, did not provide visual feedback. During a two-month period, the systems measured drying time between the moment of dispensing ABHR and opening the incubator's doors. The drying times of the incubators were compared with and without feedback. Findings: Of the 6422 recorded hand hygiene events, 658 were valid for data analysis. Compliance with correct drying time reached 75% (N = 397/526) for incubators equipped with visual feedback versus 36% (N = 48/132; P < 0.0001) for incubators lacking this feature. Conclusion: The ITL improves compliance with the recommended 30 s ABHR drying time in a NICU setting.

Inflicted head injury by shaking trauma (IHI-ST) in infants is a type of abusive head trauma often simulated computationally to investigate causalities between violent shaking and injury. This is commonly done with the head’s rotation center kept fixed over time. However, due to the flexibility of the infant’s neck and the external shaking motion imposed by the perpetrator it is unlikely that the rotation center is static. Using a test-dummy, shaken by volunteers, we demonstrated experimentally that the location of the head’s rotation center moves considerably over time. We further showed that implementation of a spatiotemporal-varying rotation center in an improved kinematic model resulted in strongly improved replication of shaking compared to existing methods. Hence, we stress that the validity of current infant shaking injury risk assessments and the injury thresholds on which these assessments are based, both often used in court cases, should be re-evaluated., Medical Instruments & Bio-Inspired Technology

Introduction: Based on the success of the former “Shaft-Actuated, Tip-Articulated” SATA-Drive, a prototype robotic instrument driver for modular, steerable, laparoscopic instruments, a new driver is designed and tested to improve previously lacking features concerning cleanability, instrument adaptation, practical application and control. The design of the driver engages these issues with a modular design aimed at re-use of both the instrument and the driver, for which a set of design requirements are established. Methods: A new modular design has been developed to improve cleanability through separation of the electro-motors and the instrument mechanism which clutches the instrument. Contamination of the driver’s robotic side is prevented though a combination of a drape and a Sterile barrier interface, while the instrument side is made sterilizable. A novel instrument clutching mechanism enables quick-release features, while a motor-axis latching mechanism enables plug-and-play assembly. Embedded sensors allow precise and fast control. A user-experiment was conducted on instrument exchange and assembly time, while mechanical and electrical tests were conducted on the driver’s responsiveness. Results: The driver has proven its ability to control the instrument, after which it can be disassembled for cleaning and inspection. The driver is designed for re-use through disassembled sterilization where all possibly contaminated surfaces are exposable for cleaning and inspection. The new standardized instrument clutches allow easy instrument (dis-)assembly. Instrument exchange is possible in two methods, the fastest of which is a median of 11 (6.3–14.6) seconds. The driver’s instrument mechanism is separated in a median of 3.7 (1.8–8.1) seconds. After assembly, the driver is operational in less than 2 s. Discussion: Instrument exchange times are similar to the semi-reusable Da Vinci systems, yet the MISLI-Drive is designed for sterilization, ins, Medical Instruments & Bio-Inspired Technology

Background: Surgical process model (SPM) analysis is a great means to predict the surgical steps in a procedure as well as to predict the potential impact of new technologies. Especially in complicated and high-volume treatments, such as parenchyma sparing laparoscopic liver resection (LLR), profound process knowledge is essential for enabling improving surgical quality and efficiency. Methods: Videos of thirteen parenchyma sparing LLR were analyzed to extract the duration and sequence of surgical steps according to the process model. The videos were categorized into three groups, based on the tumor locations. Next, a detailed discrete events simulation model (DESM) of LLR was built, based on the process model and the process data obtained from the endoscopic videos. Furthermore, the impact of using a navigation platform on the total duration of the LLR was studied with the simulation model by assessing three different scenarios: (i) no navigation platform, (ii) conservative positive effect, and (iii) optimistic positive effect. Results: The possible variations of sequences of surgical steps in performing parenchyma sparing depending on the tumor locations were established. The statistically most probable chain of surgical steps was predicted, which could be used to improve parenchyma sparing surgeries. In all three categories (i–iii) the treatment phase covered the major part (~ 40%) of the total procedure duration (bottleneck). The simulation results predict that a navigation platform could decrease the total surgery duration by up to 30%. Conclusion: This study showed a DESM based on the analysis of steps during surgical procedures can be used to predict the impact of new technology. SPMs can be used to detect, e.g., the most probable workflow paths which enables predicting next surgical steps, improving surgical training systems, and analyzing surgical performance. Moreover, it provides insight into the points for improvement and bottlenecks in the surgical p, Medical Instruments & Bio-Inspired Technology

Background: Veress needles (VN) are commonly used in establishing pneumoperitoneum in laparoscopic surgery. Previously, a VN with a new safety mechanism ‘VeressPLUS’ needle (VN+) was developed to reduce the amount of overshoot. Methods: Eighteen participants (novices, intermediates, and experts) performed in total of 248 insertions in a systematic way on Thiel-embalmed bodies with wide and small bore versions of the conventional VN (VNc) and the VN+. Insertion depth was measured by recording the graduations on the needle under direct laparoscopic vision. Results: Participants graded the bodies and the procedures as lifelike. Overall, a significant reduction (P<0.001) in average insertion depth was found for the VN+ compared to the VNc of 26.0 SD16 mm versus 46.2 SD15 mm. The insertion depth difference in the novice group was higher compared to the intermediates and experts (P<0.001). The average insertion depth for both needle types was less (P<0.001) for female participants compared to male. Conclusion: This study indicated that the VN+ significantly reduced the insertion depth in all tested conditions. Whether the difference between female and male performance can be linked to differences in muscle control or arm mass should be further investigated. Useful technical information was gathered from this study to further improve the VN+., Biomechanical Engineering, Medical Instruments & Bio-Inspired Technology

In this article, a deep learning method for the shape sensing of continuum robots based on multicore fiber bragg grating (FBG) fiber is introduced. The proposed method, based on an artificial neural network (ANN), differs from traditional approaches, where accurate shape reconstruction requires a tedious characterization of many characteristic parameters. A further limitation of traditional approaches is that they require either multiple fibers, whose location relative to the centerline must be precisely known (calibrated), or a single multicore fiber whose position typically coincides with the neutral line. The proposed method addresses this limitation and, thus, allows shape sensing based on a single multicore fiber placed off-center. This helps in miniaturizing and leaves the central channel available for other purposes. The proposed approach was compared to a recent state-of-the-art model-based shape sensing approach. A two-degree-of-freedom benchtop fluidics-driven catheter system was built to validate the proposed ANN. The proposed ANN-based shape sensing approach was evaluated on a 40-mm-long steerable continuum robot in both 3-D free-space and 2-D constrained environments, yielding an average shape sensing error of 0.24 and 0.49 mm, respectively. With these results, the superiority of the proposed approach compared to the recent model-based shape sensing method was demonstrated., Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Medical Instruments & Bio-Inspired Technology

Objectives: Normothermic machine perfusion (NMP) provides a platform for pre-transplant kidney quality assessment that is essential for the use of marginal donor kidneys. Laser speckle contrast imaging (LSCI) presents distinct advantages as a real-time and noncontact imaging technique for measuring microcirculation. In this study, we aimed to assess the value of LSCI in visualizing renal cortical perfusion and investigate the additional value of dual-side LSCI measurements compared to single aspect measurement during NMP. Methods: Porcine kidneys were obtained from a slaughterhouse and then underwent NMP. LSCI was used to measure one-sided cortical perfusion in the first 100 min of NMP. Thereafter, the inferior renal artery branch was occluded to induce partial ischemia and LSCI measurements on both ventral and dorsal sides were performed. Results: LSCI fluxes correlated linearly with the renal blood flow (R2 = 0.90, p < 0.001). After renal artery branch occlusion, absence of renal cortical perfusion could be visualized and semiquantified by LSCI. The overall ischemic area percentage of the ventral and dorsal sides was comparable (median interquartile range [IQR], 38 [24−43]% vs. 29 [17−46]%, p = 0.43), but heterogenous patterns between the two aspects were observed. There was a significant difference in oxygen consumption (mean ± standard deviation [SD], 2.57 ± 0.63 vs. 1.83 ± 0.49 mLO2/min/100 g, p < 0.001), urine output (median [IQR], 1.3 [1.1−1.7] vs. 0.8 [0.6−1.3] mL/min, p < 0.05), lactate dehydrogenase (mean ± SD, 768 ± 370 vs. 905 ± 401 U/L, p < 0.05) and AST (mean ± SD, 352 ± 285 vs. 462 ± 383 U/L, p < 0.01) before and after renal artery occlusion, while no significant difference was found in creatinine clearance, fractional excretion of sodium, total sodium reabsorption and histological damage. Conclusions: LSCI fluxes correlated linearly with renal blood flow during NMP. Renal cortical microcirculation and absent pe, Medical Instruments & Bio-Inspired Technology

In laparoscopic surgery, quality of haptic feedback is reduced compared to conventional surgery, leading to unintentional tissue damage during grasping. From the perspective of haptics, poor mechanical design of laparoscopic instrument joints induces friction and a nonlinear actuation-tip force relation. In this study, a novel laparoscopic grasper using compliant joints and a magnetic balancer is presented, and the reduction in hysteresis and friction is evaluated. The hysteresis loop of the novel compliant grasper and two conventional laparoscopic graspers (high quality leading commercial brand and low quality unbranded grasper) were measured. In order to assess quality of haptic feedback, the lowest grasper tip load perceivable by instrument users was measured with the novel and the conventional laparoscopic graspers. The hysteresis loop measurement yielded a mechanical efficiency of 43% for the novel grasper, compared to- 25% and 23% for the Aesculap and the unbranded grasper, respectively. The forces perceivable by the user through the novel grasper were significantly lower (mean 1.37N, SD 0.44N) than those of conventional graspers (mean 2.15N, SD 0.71N and mean 2.65N, SD 1.20N, respectively). The balanced compliant grasper technology has the ability to improve the quality of haptic feedback compared to conventional laparoscopic graspers. Research is needed to relate these results to soft and delicate tissue grasping in a clinical setting, for which this instrument is intended., Medical Instruments & Bio-Inspired Technology

Increased demand for less invasive procedures has accelerated the adoption of Intraluminal Procedures (IP) and Endovascular Interventions (EI) performed through body lumens and vessels. As navigation through lumens and vessels is quite complex, interest grows to establish autonomous navigation techniques for IP and EI for reaching the target area. Current research efforts are directed toward increasing the Level of Autonomy (LoA) during the navigation phase. One key ingredient for autonomous navigation is Motion Planning (MP) techniques. This paper provides an overview of MP techniques categorizing them based on LoA. Our analysis investigates advances for the different clinical scenarios. Through a systematic literature analysis using the PRISMA method, the study summarizes relevant works and investigates the clinical aim, LoA, adopted MP techniques, and validation types. We identify the limitations of the corresponding MP methods and provide directions to improve the robustness of the algorithms in dynamic intraluminal environments. MP for IP and EI can be classified into four subgroups: node, sampling, optimization, and learning-based techniques, with a notable rise in learning-based approaches in recent years. One of the review's contributions is the identification of the limiting factors in IP and EI robotic systems hindering higher levels of autonomous navigation. In the future, navigation is bound to become more autonomous, placing the clinician in a supervisory position to improve control precision and reduce workload., Medical Instruments & Bio-Inspired Technology

In laparoscopic surgery the abdominal cavity is insufflated with pressurized carbon dioxide gas to create workspace. This pressure is exerted through the diaphragm onto the lungs, competing with ventilation and hampering it. In clinical practice the difficulty of optimizing this balance can lead to the application of harmfully high pressures. This study set out to create a research platform for the investigation of the complex interaction between insufflation and ventilation in an animal model. The research platform was constructed to incorporate insufflation, ventilation and relevant hemodynamic monitoring devices, controlling insufflation and ventilation from a central computer. The core of the applied methodology is the fixation of physiological parameters by applying closed-loop control of specific ventilation parameters. For accurate volumetric measurements the research platform can be used in a CT scanner. An algorithm was designed to keep blood carbon dioxide and oxygen values stable, minimizing the effect of fluctuations on vascular tone and hemodynamics. This design allowed stepwise adjustment of insufflation pressure to measure the effects on ventilation and circulation. A pilot experiment in a porcine model demonstrated adequate platform performance. The developed research platform and protocol automation have the potential to increase translatability and repeatability of animal experiments on the biomechanical interactions between insufflation and ventilation., Medical Instruments & Bio-Inspired Technology

Introduction: Technology Enhanced Learning (TEL) can provide the tools to safely master minimally invasive surgery (MIS) skills in patient-free environments and receive immediate objective feedback without the constant presence of an instructor. However, TEL-based systems tend to work isolated from one another, focus on different skills, and fail to provide contents without a sound pedagogical background. Objective: The objective of this descriptive study is to present in detail EASIER, an innovative TEL platform for surgical and interventional training, as well as the results of its validation. Methods: EASIER provides a Learning Management System (LMS) for institutions and content creators that can connect and integrate TEL “external assets” (virtual reality simulators, augmented box trainers, augmented videos, etc.) addressing different skills. The platform integrates all skills under an Assessment Module that measures skills’ progress in different courses. Finally, it provides content creators with a pedagogical model to scaffold contents while retaining flexibility to approach course design with different training philosophies in mind. Three courses were developed and hosted in the platform to validate it with end-users in terms of usability, performance, learning results in the courses and student self-perception on learning. Results: In total 111 volunteers completed the validation. The study was limited due to the COVID-19 pandemic, which limited access to external assets (virtual reality simulators). Nevertheless, usability was rated with 73.1 in the System Usability Scale. Most positive aspects on performance were easiness to access the platform, easiness to change the configuration and not requiring additional plug-ins to use the platform. The platform was rated above average in the six scales of the User Experience Questionnaire. Overall, student results improved significantly across the three courses (p < 0.05). Conclusions: This study provides, w, Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Biomechanical Engineering, Medical Instruments & Bio-Inspired Technology

Emerging intraoperative tumor margin assessment techniques require the development of more complex and reliable organ phantoms to assess the performance of the technique before its translation into the clinic. In this work, electrically conductive tissue-mimicking materials (TMMs) based on fat, water and agar/gelatin were produced with tunable optical properties. The composition of the phantoms allowed for the assessment of tumor margins using diffuse reflectance spectroscopy, as the fat/water ratio served as a discriminating factor between the healthy and malignant tissue. Moreover, the possibility of using polyvinyl alcohol (PVA) or transglutaminase in combination with fat, water and gelatin for developing TMMs was studied. The diffuse spectral response of the developed phantom materials had a good match with the spectral response of porcine muscle and adipose tissue, as well as in vitro human breast tissue. Using the developed recipe, anatomically relevant heterogeneous breast phantoms representing the optical properties of different layers of the human breast were fabricated using 3D-printed molds. These TMMs can be used for further development of phantoms applicable for simulating the realistic breast conserving surgery workflow in order to evaluate the intraoperative optical-based tumor margin assessment techniques during electrosurgery., Medical Instruments & Bio-Inspired Technology

Background: In hip arthroplasties, surgeons rely on their experience to assess the stability and balance of hip tissues when fitting the implant to their patients. During the operation, surgeons use a modular, temporary set of implants to feel the tension in the surrounding soft tissues and adjust the implant configuration. This process is naturally subjective and therefore depends on the operator. Inexperienced surgeons undertaking hip arthroplasties are twice as likely to experience errors than their experienced colleagues, leading to dislocations, pain and discomfort for the patients. Methods: To address this issue, a new, 3DOF force measurement system was developed and integrated into the modular, trial implants that can quantify forces and movements intraoperatively in 3D. The prototypes were evaluated in three post-mortem human specimens (PMHSs), to provide surgeons with objective data to help determine the optimal implant fit and configuration. The devices comprise a deformable polymer material providing strain-based displacements measured with electromagnetic-based sensors and an inertial measurement unit (IMU) for motion data. Results: Device results show a relative accuracy of approx. 2% and a sensitivity of approx. 1%. PMHS results indicated that soft tissue forces on the hip joint peak in the order of ~100 N and trend with positions of the leg during range of motion (ROM) tests, although force patterns differ between each PMHS. Conclusion: By monitoring forces and force patterns of hip soft tissues, in combination with standardised ROM tests, the force patterns could shed a light on potential anomalies that can be addressed during surgery. Clinical and Translational Impact Statement: The development of an instrumented hip implant device for use during surgery knowledge will eventually allow us to develop a predictive model for soft tissue balancing, that can be used for pre- and intra-operative planning for each patient on a tailored and personalised bas, Medical Instruments & Bio-Inspired Technology, Biomaterials & Tissue Biomechanics