Palpation force modulation strategies to identify hard regions in soft tissue organs

This work was supported by EPSRC MOTION grant (grant number EP/N03211X/1), National Institute for Health Research (NIHR) Biomedical Research Centre based at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London and Vattikuti Foundation

Autonomous Robotic Palpation of Soft Tissue using the Modulation of Applied Force

Palpation or perception of tactile information from soft tissue organs during minimally invasive surgery is required to improve clinical outcomes. One of the methods of palpation includes examination using the modulation of applied force on the localized area. This paper presents a method of soft tissue autonomous palpation based on the mathematical model obtained from human tactile examination data using modulations of palpation force. Using a second order reactive auto-regressive model of applied force, a robotic probe with spherical indenter was controlled to examine silicone tissue phantoms containing artificial nodules. The results show that the autonomous palpation using the model abstracted from human demonstration can be used not only to detect embedded nodules, but also to enhance the stiffness perception compared to the static indentation of the probe

A mechatronic platform for computer aided detection of nodules in anatomopathological analyses via stiffness and ultrasound measurements

This study presents a platform for ex-vivo detection of cancer nodules, addressing automation of medical diagnoses in surgery and associated histological analyses. The proposed approach takes advantage of the property of cancer to alter the mechanical and acoustical properties of tissues, because of changes in stiffness and density. A force sensor and an ultrasound probe were combined to detect such alterations during force-regulated indentations. To explore the specimens, regardless of their orientation and shape, a scanned area of the test sample was defined using shape recognition applying optical background subtraction to the images captured by a camera. The motorized platform was validated using seven phantom tissues, simulating the mechanical and acoustical properties of ex-vivo diseased tissues, including stiffer nodules that can be encountered in pathological conditions during histological analyses. Results demonstrated the platform’s ability to automatically explore and identify the inclusions in the phantom. Overall, the system was able to correctly identify up to 90.3% of the inclusions by means of stiffness in combination with ultrasound measurements, paving pathways towards robotic palpation during intraoperative examinations

A Sensor Based Approach to Analyzing Motion in Medical Applications: AV Fistula Cannulation and Rett Syndrome

Sensor based motion analysis is employed to assess frequency, severity and duration of Rett syndrome hand stereotypies as well as soft tissue palpation of an arteriovenous fistula. The only prior quantification of Rett symptoms have been visually in a clinical setting; defining palpation skill is largely unprecedented aside from breast tissue examination. We evaluate various sensors used to track motion, measure electromyography, galvanic skin response, and heart rate. The Leap motion controller is evaluated for the viability of tracking hand palpation. Verification tests are performed for determining the feasibility, accuracy, and precision of each sensor. A static phantom was defined as the two endpoints of each of the six fistulas within the palpation simulator and the accuracy of the Leap Motion was \u3c0.9 cm. The 9 DOF motion sensor, EMG sensor, and heart rate sensor all pass their respective verification tests. The galvanic skin response sensor needs further thought into where the electrodes should be placed for proper readings to ensue. All sensors present acceptable precision and accuracy values within the proposed environment; improvements still need to be made for increased performance. Once resolved and perfected, validation studies should verify the preliminary trends of Rett patients’ hand stereotypy quantification and palpation by expert versus novice hemodialysis nurses

Equine cervical pain and dysfunction

2021 Fall.Includes bibliographical references.Cervical pain and dysfunction in horses has become more recognized in recent years. However, a horse may present with a long list of different clinical syndromes and the examination findings can be confusing, resulting in difficulty effectively treating the horse. This frequently leads to frustration by the owner, as well as the veterinarian charged with helping the horse. This body of work aims to enlighten the reader of the dearth of understanding of cervical pain and dysfunction, to highlight how dangerous behavior may be related to cervical pain, and describe the course and development of future research. There is a paucity of peer-reviewed equine literature available describing cervical pain and dysfunction in the horse. The first chapter is designed to provide a synopsis of the current state of understanding of the disease processes, diagnostic capabilities, and possible treatment strategies available to manage cervical pain and dysfunction in horses. The second chapter describes a series of horses displaying unwanted behavior that became dangerous to the rider and often times to the horse itself. The included horses all had moderate to severe ganglionitis at multiple vertebral levels. Ganglionitis has been associated with neuropathic pain in other species, and is believed to be causing a state of neuropathic pain in this series of horses. This study highlights the need for deeper understanding of pain behavior in horses. Chapter 3 describes a prospective evaluation of cervical pain and dysfunction in 12 horses. Recombinant equine interleukin-1β (reIL-1β) has been used as an acute synovitis model within the appendicular skeleton and was utilized in this study to create transient synovitis at the cervical articulation of C5-C6. This study evaluated the clinical, biomechanical and ultrasonographic features in horses with a known source of neck pain. Acute synovitis of the articular process joint (APJ) induced clinical signs of myofascial pain and neck stiffness with variable degrees of forelimb lameness. Ultrasonographic evidence of the presence and severity of APJ effusion could be readily identified and tracked over time. Utilizing this model in the future could further add to our understanding of the clinical presentations in horses experiencing cervical pain and dysfunction. Through this collection of work, we have developed collaborations to investigate many unanswered questions that have been raised. We will look to define pathways related to neuropathic pain mechanisms in order to ultimately improve the quality of life, not only for our equine patients, but potentially of other veterinary species and even the human population experiencing chronic pain

Structuring of tactile sensory information for category formation in robotics palpation

Abstract: This paper proposes a framework to investigate the influence of physical interactions to sensory information, during robotic palpation. We embed a capacitive tactile sensor on a robotic arm to probe a soft phantom and detect and classify hard inclusions within it. A combination of PCA and K-Means clustering is used to: first, reduce the dimensionality of the spatiotemporal data obtained through the probing of each area in the phantom; second categorize the re-encoded data into a given number of categories. Results show that appropriate probing interactions can be useful in compensating for the quality of the data, or lack thereof. Finally, we test the proposed framework on a palpation scenario where a Support Vector Machine classifier is trained to discriminate amongst different types of hard inclusions. We show the proposed framework is capable of predicting the best-performing motion strategy, as well as the relative classification performance of the SVM classifier, solely based on unsupervised cluster analysis methods