18 research outputs found
Investigation of rapid evaporative ionisation mass spectrometry (REIMS) in minimally invasive surgery
No full textPrecision surgery requires technologies that can be used in-situ and can deliver real-time analysis of intra-operative pathology. Currently, surgical strategy is conceived using pre-operative imaging and visual assessment of anatomy intraoperatively, with postoperative histology guiding the necessity for any future intervention. This approach is often subjective, time-consuming, and costly.
This project describes the validation of the Harmonic scalpel; an energy device commonly used in minimally invasive surgery, as a new surgical aerosol source for REIMS analysis. The generated surgical aerosol produced during the dissection of different porcine tissues was collected and analysed by REIMS, producing tissue-specific lipid profiles in positive and negative ionisation modes. Comparison with other surgical energy tools, such as monopolar electrosurgery and CO2 laser was made. Classification performance of the Harmonic-REIMS platform was assessed on different porcine tissue models showing 100% accuracy.
To further understand how different technical and environmental conditions can impact the metabolic composition of colorectal mucosa tissue and affect REIMS spectra using the Harmonic device, a phantom environment was designed and developed. Real-time measurements of different conditions and spectral information were assessed, showing how REIMS is most likely to be impacted by changes in humidity, temperature, and presence of mucosal contamination, during the in vivo translation of the technology.
Using the Harmonic-REIMS platform, a clinically annotated spectral database (n=286) was created ex vivo, including colorectal tissue from 23 patients. The diagnostic accuracy of REIMS in differentiating normal and tumour samples was assessed showing an overall diagnostic accuracy of 94%. Finally, as part of the translation of REIMS technology in minimally invasive surgery, in vivo human feasibility studies were made in laparoscopic and robotic surgery.Open Acces
Semantic Security Invariance under Variant Computational Assumptions
No full textA game-based cryptographic proof is a relation that establishes equivalence between probabilistic sequences of actions by real and ideal world players. The author of a proof selects a hardness assumption system for their proof upon which to base their subsequent statements. In this paper, we prove the existence of proof-invariant transformations for varying hardness assumptions. We show that for two systems satisfying certain algebraic properties any proof in one system has an equivalent valid proof in the other. This validates Kurosawa’s remark about the existence of proof similarities.
Our result implies a correspondence between the Learning With Errors (LWE) problems and both the Elliptic Curve Discrete Log problem (ECDLP) and the Discrete Logarithm (DLOG) problem. To illustrate this result, we provide a series of example transformations in the appendix. The concrete result of this paper is a prototype proof translation tool
Human robotic surgery with intraoperative tissue identification using rapid evaporation ionisation mass spectrometry
No full textInstantaneous, continuous, and reliable information on the molecular biology of surgical target tissue could significantly contribute to the precision, safety, and speed of the intervention. In this work, we introduced a methodology for chemical tissue identification in robotic surgery using rapid evaporative ionisation mass spectrometry. We developed a surgical aerosol evacuation system that is compatible with a robotic platform enabling consistent intraoperative sample collection and assessed the feasibility of this platform during head and neck surgical cases, using two different surgical energy devices. Our data showed specific, characteristic lipid profiles associated with the tissue type including various ceramides, glycerophospholipids, and glycerolipids, as well as different ion formation mechanisms based on the energy device used. This platform allows continuous and accurate intraoperative mass spectrometry-based identification of ablated/resected tissue and in combination with robotic registration of images, time, and anatomical positions can improve the current robot-assisted surgical platforms and guide surgical strategy
Validation of ultrasonic harmonic scalpel for real-time tissue identification using rapid evaporative ionization mass spectrometry
No full textIn this study, we integrate rapid evaporative ionization mass spectrometry (REIMS) with the Harmonic scalpel, an advanced laparoscopic surgical instrument that utilizes ultrasound energy to dissect and coagulate tissues. It provides unparalleled manipulation capability to surgeons and has superseded traditional electrosurgical tools particularly in abdominal surgery, but is yet to be validated with REIMS. The REIMS platform coupled with the Harmonic device was shown to produce tissue-specific lipid profiles through the analysis of porcine tissues in both negative and positive ionization modes. Comparison with other methods of electrosurgical dissection, such as monopolar electrosurgery and CO2 laser, showed spectral differences in the profile dependent on the energy device used. The Harmonic device demonstrated major spectral differences in the phospholipid region of m/z 600–1000 compared with the monopolar electrosurgical and CO2 laser-generated spectra. Within the Harmonic REIMS spectra, high intensities of diglycerides and triglycerides were observed. In contrast, monopolar electrosurgical and laser spectra demonstrated high abundances of glycerophospholipids. The Harmonic scalpel was able to differentiate between the liver, muscle, colon, and small intestine, demonstrating 100% diagnostic accuracy. The validation of the Harmonic device–mass spectrometry combination will allow the platform to be used safely and robustly for real-time in vivo surgical tissue identification in a variety of clinical applications
Mass spectrometry transanal minimally invasive surgery (MS-TAMIS) to promote organ preservation in rectal cancer
No full textBACKGROUND: Transanal minimally invasive surgery (TAMIS) is deployed for organ preservation in early rectal cancer and significant rectal polyps. Rapid evaporative ionisation mass spectrometry (REIMS) provides biochemical tissue analysis, which could be applied intraoperatively to give real-time tissue feedback to the surgeon and decrease the risk of an involved margin. However, the accuracy and feasibility of this approach have not been established. METHODS: In this prospective observational study, patients undergoing resection of rectal adenomas or carcinomas were recruited. An electrosurgical handpiece analysed tissues ex vivo using diathermy, with the aerosol aspirated into a Xevo G2-S ToF mass spectrometer. The relative abundance of lipids underwent predictive statistical modelling and leave-one-patient-out cross-validation. The outcomes of interest were the ability of REIMS to differentiate normal, adenomatous and cancerous tissue, or any disease subtype from normal. REIMS was coupled with TAMIS for in vivo sampling, assessing the accuracy of tissue recognition and distinguishing bowel wall layers. RESULTS: Forty-seven patients were included, yielding 266 spectra (121 normal, 109 tumour and 36 adenoma). REIMS differentiates normal, adenomatous and cancerous rectal tissues with 86.8% accuracy, and normal and adenomatous tissue with 92.4% accuracy and 91.4% accuracy when differentiating disease from normal. We have performed the first five in-man mass spectrometry augmented TAMIS (MS-TAMIS). In real time, MS-TAMIS can differentiate rectal mucosa and submucosa based on their relative abundance of triglycerides and glycerophospholipids. The ex vivo accuracy distinguishing diseased and normal tissues is maintained in vivo at 90%, with negative predictive value of 95%. The system identified a deep and lateral involved tumour margin during TAMIS. CONCLUSIONS: REIMS distinguishes rectal tissue types based on underlying lipid biology, and this can be translated in vivo by coupling it to TAMIS. There is a role for this technology in improving the efficacy of resection of early rectal cancers
Functional optimization of fluidic devices with differentiable stokes flow
No full text© 2020 Owner/Author. We present a method for performance-driven optimization of fluidic devices. In our approach, engineers provide a high-level specification of a device using parametric surfaces for the fluid-solid boundaries. They also specify desired flow properties for inlets and outlets of the device. Our computational approach optimizes the boundary of the fluidic device such that its steady-state flow matches desired flow at outlets. In order to deal with computational challenges of this task, we propose an efficient, differentiable Stokes flow solver. Our solver provides explicit access to gradients of performance metrics with respect to the parametric boundary representation. This key feature allows us to couple the solver with efficient gradient-based optimization methods. We demonstrate the efficacy of this approach on designs of five complex 3D fluidic systems. Our approach makes an important step towards practical computational design tools for high-performance fluidic devices
Pure ankle dislocation after modified Broström repair for chronic lateral instability: Case report and literature review
No full textAnkle dislocation with no concomitant malleolar fracture is an overwhelmingly rare injury, and only a relatively limited number of cases have been reported. Diligent management regarding the treatment of these injuries is requisite to attain an auspicious outcome. Lateral ankle instability is a frequent condition that can derive from recurrent sprains, predominantly at a young age. Broström repair, with its modifications and updates, has been established as the optimal solution when treating chronic lateral unsteadiness. We present a peculiar case of a posteromedial ankle dislocation without accompanying fracture in a patient operated on many years before the injury for chronic lateral instability with a modified Broström procedure. No similar case could be retrieved in the existing literature. After the initial clinical and radiological assessment, urgent closed reduction of the dislocation was achieved, and the foot was immobilized. Further imaging was carried out to evaluate the features of the injury. It was deduced that the repairs from the previous operation were intact. The patient was operated on to repair the distal tibiofibular syndesmosis. The postoperative course was uneventful, and absolute functional capacity was eventually accomplished. Demonstrating this rare case, we accentuate the role of implementing the modified Broström procedure in the surgical treatment of chronic lateral ankle instability. © 2023 The Author
Sa1207 - Prospective Observational Cohort Study of Rapid Ionization Mass Spectrometry (Reims) for Near-Real Time Diagnosis and Stratification of Colorectal Cancer
No full textAbstract 4536: Rapid evaporative ionization mass spectrometry (REIMS) analysis of the mucosal lipidome has a high diagnostic accuracy for adenomas and early colorectal cancer
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