Robotic simulators for tissue examination training with multimodal sensory feedback

Tissue examination by hand remains an essential technique in clinical practice. The effective application depends on skills in sensorimotor coordination, mainly involving haptic, visual, and auditory feedback. The skills clinicians have to learn can be as subtle as regulating finger pressure with breathing, choosing palpation action, monitoring involuntary facial and vocal expressions in response to palpation, and using pain expressions both as a source of information and as a constraint on physical examination. Patient simulators can provide a safe learning platform to novice physicians before trying real patients. This paper reviews state-of-the-art medical simulators for the training for the first time with a consideration of providing multimodal feedback to learn as many manual examination techniques as possible. The study summarizes current advances in tissue examination training devices simulating different medical conditions and providing different types of feedback modalities. Opportunities with the development of pain expression, tissue modeling, actuation, and sensing are also analyzed to support the future design of effective tissue examination simulators

A comprehensive method to design and assess mixed reality simulations

AbstractThe scientific literature highlights how Mixed Reality (MR) simulations allow obtaining several benefits in healthcare education. Simulation-based training, boosted by MR, offers an exciting and immersive learning experience that helps health professionals to acquire knowledge and skills, without exposing patients to unnecessary risks. High engagement, informational overload, and unfamiliarity with virtual elements could expose students to cognitive overload and acute stress. The implementation of effective simulation design strategies able to preserve the psychological safety of learners and the investigation of the impacts and effects of simulations are two open challenges to be faced. In this context, the present study proposes a method to design a medical simulation and evaluate its effectiveness, with the final aim to achieve the learning outcomes and do not compromise the students' psychological safety. The method has been applied in the design and development of an MR application to simulate the rachicentesis procedure for diagnostic purposes in adults. The MR application has been tested by involving twenty students of the 6th year of Medicine and Surgery of Università Politecnica delle Marche. Multiple measurement techniques such as self-report, physiological indices, and observer ratings of performance, cognitive and emotional states of learners have been implemented to improve the rigour of the study. Also, a user-experience analysis has been accomplished to discriminate between two different devices: Vox Gear Plus® and Microsoft Hololens®. To compare the results with a reference, students performed the simulation also without using the MR application. The use of MR resulted in increased stress measured by physiological parameters without a high increase in perceived workload. It satisfies the objective to enhance the realism of the simulation without generating cognitive overload, which favours productive learning. The user experience (UX) has found greater benefits in involvement, immersion, and realism; however, it has emphasized the technological limitations of devices such as obstruction, loss of depth (Vox Gear Plus), and narrow FOV (Microsoft Hololens)

W-FYD: a Wearable Fabric-based Display for Haptic Multi-Cue Delivery and Tactile Augmented Reality

Despite the importance of softness, there is no evidence of wearable haptic systems able to deliver controllable softness cues. Here, we present the Wearable Fabric Yielding Display (W-FYD), a fabric-based display for multi-cue delivery that can be worn on user's finger and enables, for the first time, both active and passive softness exploration. It can also induce a sliding effect under the finger-pad. A given stiffness profile can be obtained by modulating the stretching state of the fabric through two motors. Furthermore, a lifting mechanism allows to put the fabric in contact with the user's finger-pad, to enable passive softness rendering. In this paper, we describe the architecture of W-FYD, and a thorough characterization of its stiffness workspace, frequency response and softness rendering capabilities. We also computed device Just Noticeable Difference in both active and passive exploratory conditions, for linear and non-linear stiffness rendering as well as for sliding direction perception. The effect of device weight was also considered. Furthermore, performance of participants and their subjective quantitative evaluation in detecting sliding direction and softness discrimination tasks are reported. Finally, applications of W-FYD in tactile augmented reality for open palpation are discussed, opening interesting perspectives in many fields of human-machine interaction

Effectiveness analysis of traditional and mixed reality simulations in medical training: a methodological approach for the assessment of stress, cognitive load and performance

La simulazione nell'educazione in medicina è considerata un metodo di formazione in grado di migliorare le competenze cliniche e il comportamento degli operatori sanitari e, di conseguenza, la qualità dell'assistenza per il paziente. Inoltre, l'utilizzo di nuove tecnologie come la Realtà Aumentata, offre ai discenti l'opportunità di esercitarsi in un ambiente immersivo. L'opportunità di sperimentare questo innovativo metodo didattico è efficace non solo nel ridurre il rischio di errori e approcci sbagliati ma anche nel provare ansia e stress simili a quelli avvertiti nella pratica reale. La sfida sta nel trovare il giusto equilibrio. I discenti devono infatti provare lo stesso stress che avvertirebbero lavorando ad un vero caso clinico ma, allo stesso tempo, devono essere controllati ed evitati possibili disturbi da stress post-traumatico, verificabili soprattutto nel campo della gestione delle emergenze (pronto soccorso). Inoltre, è fondamentale anche ottenere alte prestazioni e un apprendimento adeguato, evitando sovraccarichi cognitivi che influenzerebbero negativamente l’apprendimento. Tuttavia, ad oggi mancano ancora studi approfonditi sull'impatto che le simulazioni mediche hanno su stress, frustrazione, carico cognitivo e apprendimento dei discenti. Per questo motivo, l'obiettivo principale di questo studio è valutare l'efficacia del training tramite simulazione, analizzando prestazioni, ansia, stress e carico cognitivo durante simulazioni cliniche tradizionali (con manichino) ed avanzate (in realtà mista). A questo scopo, è stato sviluppato un approccio metodologico strutturato e completo per valutare le prestazioni, le condizioni emotive e cognitive degli studenti. Questo comprende l'acquisizione e l'analisi di parametri psicologici (valutazione soggettiva), segnali biometrici (valutazione oggettiva) e prestazioni. Questa indagine consente di evidenziare i punti deboli delle simulazioni e offre l'opportunità di definire utili linee guida per la riprogettazione e l'ottimizzazione delle stesse. La metodologia è stata applicata su tre casi studio: il primo si riferisce a simulazioni ad alta fedeltà per la gestione del paziente in pronto soccorso, il secondo si riferisce a simulazioni a bassa fedeltà per la pratica della rachicentesi. Per il terzo caso studio, è stato progettato e sviluppato un prototipo di simulatore in realtà mista per la rachicentesi, con l'obiettivo di migliorare il senso di realismo e immersione della simulazione a bassa fedeltà. 148 studenti sono stati coinvolti nei primi due casi studio osservazionali, mentre soltanto 36 studenti hanno preso parte allo studio pilota sulla simulazione in realtà mista. In tutti i casi di studio sono state effettuate analisi descrittive delle prestazioni, degli stati cognitivi ed emotivi. Per le simulazioni ad alta e bassa fedeltà, le analisi di regressione statistica hanno evidenziato quali variabili influenzano le prestazioni, lo stress e il carico cognitivo degli studenti. Per lo studio pilota sulla realtà mista, l'analisi della user experience ha sottolineato i limiti tecnici della nuova tecnologia.Simulation in medical education is considered a training method capable of improving clinical competence and practitioners’ behaviour, and, consequently quality of care and patient’s outcome. Moreover, the use of new technologies, such as augmented reality, offers to the learners the opportunity to engage themselves in an immersive environment. The opportunity to experiment with this innovative instructional method is effective not only in reducing the risk of errors and wrong approaches but also in experiencing anxiety and stress as in real practice. The challenge is to find the right stress balance: learners have to feel as if they were practicing in the real stressful clinical case, and, at the same time, post-traumatic stress disorders, verifiable especially in the emergency field, must be controlled and avoided. Moreover, it is fundamental also to obtain high performance and learning, thus avoiding cognitive overloads. However, extensive researches about the impact of medical simulations on students’ stress, frustration, cognitive load, and learning are still lacking. For this reason, the main objective of this study is to assess simulation training effectiveness by analysing performance, anxiety, stress, and cognitive load during traditional (with manikin) and advanced (with augmented reality) clinical simulations. A structured and comprehensive methodological approach to assess performance, emotional and cognitive conditions of students has been developed. It includes the acquisition and analysis of psychological parameters (subjective assessment), biometric signals (objective assessment), and task performance. This investigation allows to point out simulations’ weaknesses and offers the opportunity to define useful optimisation guidelines. The methodology has been applied to three case studies: the first one refers to high-fidelity simulations, for the patient management in the emergency room, the second one refers to low-fidelity simulation for rachicentesis. For the third case study, a prototype of a mixed reality simulator for the rachicentesis practice has been designed and developed aiming at improving the sense of realism and immersion of the low-fidelity simulation. While 148 students have been enrolled in the first two case studies, only 36 students have taken part in the pilot study about mixed reality simulation. Descriptive analysis about performance, cognitive and emotional states have been done in all the case studies. For the high-fidelity and low-fidelity simulations, the statistical regression analysis has pointed out which variables affect students’ performance, stress, and cognitive load. For the pilot study about mixed reality, the user experience analysis highlighted the technical limitations of the new technology

VISIO-HAPTIC DEFORMABLE MODEL FOR HAPTIC DOMINANT PALPATION SIMULATOR

Vision and haptic are two most important modalities in a medical simulation. While visual cues assist one to see his actions when performing a medical procedure, haptic cues enable feeling the object being manipulated during the interaction. Despite their importance in a computer simulation, the combination of both modalities has not been adequately assessed, especially that in a haptic dominant environment. Thus, resulting in poor emphasis in resource allocation management in terms of effort spent in rendering the two modalities for simulators with realistic real-time interactions. Addressing this problem requires an investigation on whether a single modality (haptic) or a combination of both visual and haptic could be better for learning skills in a haptic dominant environment such as in a palpation simulator. However, before such an investigation could take place one main technical implementation issue in visio-haptic rendering needs to be addresse

Identifying Haptic Exploratory Procedures by Analyzing Hand Dynamics and Contact Force

Haptic exploratory procedures (EPs) are prototypical hand movements that are linked to the acquisition of specific object properties. In studies of haptic perception, hand movements are often classified into these EPs. Here, we aim to investigate several EPs in a quantitative manner to understand how hand dynamics and contact forces differ between them. These dissimilarities are then used to construct an EP identification model capable of discriminating between EPs based on the index finger position and contact force. The extent to which the instructed EPs were distinct, repeatable, and similar across subjects was confirmed by showing that more than 95 percent of the analyzed trials were classified correctly. Finally, the method is employed to investigate haptic exploratory behavior during similarity judgments based on several object properties. It seems that discrimination based on material properties (hardness, roughness, and temperature) yields more consistent classification results compared to discrimination based on the acquisition of shape information. © 2013 IEEE

On-the-fly dense 3D surface reconstruction for geometry-aware augmented reality.

Augmented Reality (AR) is an emerging technology that makes seamless connections between virtual space and the real world by superimposing computer-generated information onto the real-world environment. AR can provide additional information in a more intuitive and natural way than any other information-delivery method that a human has ever in- vented. Camera tracking is the enabling technology for AR and has been well studied for the last few decades. Apart from the tracking problems, sensing and perception of the surrounding environment are also very important and challenging problems. Although there are existing hardware solutions such as Microsoft Kinect and HoloLens that can sense and build the environmental structure, they are either too bulky or too expensive for AR. In this thesis, the challenging real-time dense 3D surface reconstruction technologies are studied and reformulated for the reinvention of basic position-aware AR towards geometry-aware and the outlook of context- aware AR. We initially propose to reconstruct the dense environmental surface using the sparse point from Simultaneous Localisation and Map- ping (SLAM), but this approach is prone to fail in challenging Minimally Invasive Surgery (MIS) scenes such as the presence of deformation and surgical smoke. We subsequently adopt stereo vision with SLAM for more accurate and robust results. With the success of deep learning technology in recent years, we present learning based single image re- construction and achieve the state-of-the-art results. Moreover, we pro- posed context-aware AR, one step further from purely geometry-aware AR towards the high-level conceptual interaction modelling in complex AR environment for enhanced user experience. Finally, a learning-based smoke removal method is proposed to ensure an accurate and robust reconstruction under extreme conditions such as the presence of surgical smoke

Computer Mediated Reality Technologies: A Conceptual Framework and Survey of the State of the Art in Healthcare Intervention

The trend of an ageing and growing world population, particularly in developed countries, is expected to continue for decades to come causing an increase in demand for healthcare resources and services. Consequently, demand is growing faster than rises in funding. The UK government, in partnership with the European Commission’s Vision for 2020, propose a paradigm shift towards the delivery of more patient-centred self-care interventions, facilitated by novel ubiquitous computer mediated reality technology applications, as a key strategy to overcome the scarcity of health resources gap. If this vision is to become a reality, it is crucial that state of the art research focuses efforts on the development of applications that support the delivery of patient-centred self-care interventions