53 research outputs found

    METHODS , SYSTEMS , AND DEVICES RELATING TO SURGICAL END EFFECTORS

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    The embodiments disclosed herein relate to various medical device components , including components that can be incorporated into robotic and / or in vivo medical devices, and more specifically including end effectors that can be incorporated into such devices. Certain end effector embodiments include various vessel cautery devices that have rotational movement as well as cautery and cutting functions while maintaining a relatively compact structure. Other end effector embodiments include various end effector devices that have more than one end effector

    LOCAL CONTROL ROBOTIC SURGICAL DEVICES AND RELATED METHODS

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    The various robotic medical devices include robotic devices that are disposed within a body cavity and positioned using a support component disposed through an orifice or opening in the body cavity. Additional embodiments relate to devices having arms coupled to a device body wherein the device has a minimal profile such that the device can be easily inserted through smaller incisions in comparison to other devices without such a small profile. Further embodiments relate to methods of operating the above devices

    METHODS, SYSTEMS, AND DEVICES RELATING TO FORCE CONTROL SURGICAL SYSTEMS

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    The various embodiments herein relate to robotic surgical systems and devices that use force and/or torque sensors to measure forces applied at various components of the system or device. Certain implementations include robotic surgical devices having one or more force/torque sensors that detect or measure one or more forces applied at or on one or more arms. Other embodiments relate to systems having a robotic surgical device that has one or more sensors and an external controller that has one or more motors such that the sensors transmit information that is used at the controller to actuate the motors to provide haptic feedback to a user

    Haptic Sensing for Use in Miniature In-Vivo Robotic Grasping Tasks

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    Surgical procedures have been improved greatly through the use of minimally invasive techniques. These techniques allow the surgeon access to the abdomen of the body without the necessity of a large incision. The same reasons that allow laparoscopic procedures to produce limited scarring and reduced risk of infection hamper the surgeon. Passing long rigid tools through the skin requires advanced training for accurate control of the tools. As found by MacFarlane in An improvement on laparoscopic procedures is the implementation of surgical robots. This route can return the intuitive nature of open surgeries through providing the surgeon direct control over the tool tip, while providing a stable, reliable platform. Through these robots and their respective human interfaces, the potential for passing on haptic information, such as grasping force, can be realized. The user interface component of the system is well understood and accepted, but the initial sensing of the applied force can lead to difficulties. The da Vinci V R S Surgical System (Intuitive Surgical, Sunnyvale, CA) is the most widely used system in US for gastrointestinal procedures. This robot, even with its success relies on the surgeons experience to control the level of forces applied to the respective tissues. The da Vinci system is very large and has space if force feedback is ever desired, but in miniature surgical robots that are meant for complete insertion into the patient, space is limited. It is the forearm of a robot such as described in There have been efforts to augment the surgeons sense of touch by measuring the forces applied to laparoscopic tools under manual manipulation. The approaches in [3] and [4] have created systems that are capable of measuring the forces either directly, on the grasper itself, as well as indirectly, measured on the handle or drive system. Direct methods of sensing on the graspers can lead to unfamiliar grasper geometries as well as difficulties for sterilization. Indirect measurement is more practical for robotic applications, but due to the necessary space and the desired coupling of tool rotation and actuation, measurement of the drive rod directly can cause the overall forearm size and complexity to grow unacceptably. When a focus on grasping force is taken, Puangmali in [5] discusses several different methods for indirect and direct sensing, including optical-and displacement-based sensing. These methods were considered for their practicality in a miniature system. Indirect measurement of the applied force was chosen for both its potential size as well as its ability to be applied on a coupled drive configuration. In this paper, the initial testing of an in-line, self-contained force-sensing robotic grasper for use on miniature surgical robotic platforms is presented. This grasper has been tested in five different grasping situations, with the corresponding curves presented here as a measure of its effectiveness. Based on the verification presented here, the system will be adapted to a package capable of in vivo testing. Methods A testbed was created, Due to the consistent input conditions on the motor for each test, the measured force on any material results in same maximum force applied. When testing, the crucial component is how the force ramps up from no load to this full load, and the characteristic curves that result. As shown in Results Several grasps were conducted with each of the five end conditions. The measurements were recorded at 50 Hz. Each of the trials for a given condition was adjusted laterally to accommodate different times of contact. Once the matching cases were aligned laterally, each trial for a particular case was averaged. The resulting averages were then filtered using a rolling average that accounts for the previous four readings. The result of this filtering demonstrates distinct trends for each class of material, as shown in The three cases that represent a rigid end condition (empty and thin/thick acrylic) all demonstrate the same steep loading curve a

    Monolingual and crosslingual comparison of tandem features derived from articulatory and phone MLPs

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    In recent years, the features derived from posteriors of a multilayer perceptron (MLP), known as tandem features, have proven to be very effective for automatic speech recognition. Most tandem features to date have relied on MLPs trained for phone classification. We recently showed on a relatively small data set that MLPs trained for articulatory feature classification can be equally effective. In this paper, we provide a similar comparison using MLPs trained on a much larger data set - 2000 hours of English conversational telephone speech. We also explore how portable phone- and articulatory feature- based tandem features are in an entirely different language - Mandarin - without any retraining. We find that while phone-based features perform slightly better in the matched-language condition, they perform significantly better in the cross-language condition. Yet, in the cross-language condition, neither approach is as effective as the tandem features extracted from an MLP trained on a relatively small amount of in-domain data. Beyond feature concatenation, we also explore novel observation modelling schemes that allow for greater flexibility in combining the tandem and standard features at hidden Markov model (HMM) outputs

    Articulatory feature-based methods for acoustic and audio-visual speech recognition: Summary from the 2006 JHU Summer Workshop.

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    We report on investigations, conducted at the 2006 Johns HopkinsWorkshop, into the use of articulatory features (AFs) for observation and pronunciation models in speech recognition. In the area of observation modeling, we use the outputs of AF classiers both directly, in an extension of hybrid HMM/neural network models, and as part of the observation vector, an extension of the tandem approach. In the area of pronunciation modeling, we investigate a model having multiple streams of AF states with soft synchrony constraints, for both audio-only and audio-visual recognition. The models are implemented as dynamic Bayesian networks, and tested on tasks from the Small-Vocabulary Switchboard (SVitchboard) corpus and the CUAVE audio-visual digits corpus. Finally, we analyze AF classication and forced alignment using a newly collected set of feature-level manual transcriptions

    The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

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    Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age  6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score  652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

    Effects of alirocumab on types of myocardial infarction: insights from the ODYSSEY OUTCOMES trial

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    Aims  The third Universal Definition of Myocardial Infarction (MI) Task Force classified MIs into five types: Type 1, spontaneous; Type 2, related to oxygen supply/demand imbalance; Type 3, fatal without ascertainment of cardiac biomarkers; Type 4, related to percutaneous coronary intervention; and Type 5, related to coronary artery bypass surgery. Low-density lipoprotein cholesterol (LDL-C) reduction with statins and proprotein convertase subtilisin–kexin Type 9 (PCSK9) inhibitors reduces risk of MI, but less is known about effects on types of MI. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome (ACS) and elevated LDL-C (≥1.8 mmol/L) despite intensive statin therapy. In a pre-specified analysis, we assessed the effects of alirocumab on types of MI. Methods and results  Median follow-up was 2.8 years. Myocardial infarction types were prospectively adjudicated and classified. Of 1860 total MIs, 1223 (65.8%) were adjudicated as Type 1, 386 (20.8%) as Type 2, and 244 (13.1%) as Type 4. Few events were Type 3 (n = 2) or Type 5 (n = 5). Alirocumab reduced first MIs [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77–0.95; P = 0.003], with reductions in both Type 1 (HR 0.87, 95% CI 0.77–0.99; P = 0.032) and Type 2 (0.77, 0.61–0.97; P = 0.025), but not Type 4 MI. Conclusion  After ACS, alirocumab added to intensive statin therapy favourably impacted on Type 1 and 2 MIs. The data indicate for the first time that a lipid-lowering therapy can attenuate the risk of Type 2 MI. Low-density lipoprotein cholesterol reduction below levels achievable with statins is an effective preventive strategy for both MI types.For complete list of authors see http://dx.doi.org/10.1093/eurheartj/ehz299</p
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