2,390 research outputs found

    Understanding nonlinear vibration behaviours in high-power ultrasonic surgical devices

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    Ultrasonic surgical devices are increasingly used in oral, craniofacial and maxillofacial surgery to cut mineralized tissue, offering the surgeon high accuracy with minimal risk to nerve and vessel tissue. Power ultrasonic devices operate in resonance, requiring their length to be a half-wavelength or multiple-half-wavelength. For bone surgery, devices based on a half-wavelength have seen considerable success, but longer multiple-half-wavelength endoscopic devices have recently been proposed to widen the range of surgeries. To provide context for these developments, some examples of surgical procedures and the associated designs of ultrasonic cutting tips are presented. However, multiple-half-wavelength components, typical of endoscopic devices, have greater potential to exhibit nonlinear dynamic behaviours that have a highly detrimental effect on device performance. Through experimental characterization of the dynamic behaviour of endoscopic devices, it is demonstrated how geometrical features influence nonlinear dynamic responses. Period doubling, a known route to chaotic behaviour, is shown to be significantly influenced by the cutting tip shape, whereas the cutting tip has only a limited effect on Duffing-like responses, particularly the shape of the hysteresis curve, which is important for device stability. These findings underpin design, aiming to pave the way for a new generation of ultrasonic endoscopic surgical devices

    Novel Glaucoma Surgical Devices

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    Patient-reported outcomes measures and patient preferences for minimally invasive glaucoma surgical devices.

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    BackgroundMany therapeutic options are available to glaucoma patients. One recent therapeutic option is minimally invasive glaucoma surgical (MIGS) devices. It is unclear how patients view different treatments and which patient-reported outcomes would be most relevant in patients with mild to moderate glaucoma. We developed a questionnaire for patients eligible for MIGS devices and a patient preference study to examine the value patients place on certain outcomes associated with glaucoma and its therapies.ObjectivesTo summarize the progress to date.MethodsQuestionnaire development: We drafted the questionnaire items based on input from one physician and four patient focus groups, and a review of the literature. We tested item clarity with six cognitive interviews. These items were further refined. Patient preference study: We identified important benefit and risk outcomes qualitatively using semi-structured, one-on-one interviews with patients who were eligible for MIGS devices. We then prioritized these outcomes quantitatively using best-worst scaling methods.ResultsQuestionnaire testing: Three concepts were deemed relevant for the questionnaire: functional limitations, symptoms, and psychosocial factors. We will evaluate the reliability and validity of the 52-item draft questionnaire in an upcoming field test. Patient preference study: We identified 13 outcomes that participants perceived as important. Outcomes with the largest relative importance weights were "adequate IOP control" and "drive a car during the day."ConclusionsPatients have the potential to steer clinical research towards outcomes that are important to them. Incorporating patients' perspectives into the MIGS device development and evaluation process may expedite innovation and availability of these devices

    Design of Miniature Ultrasonic Surgical Devices

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    Orthopaedic surgery involves cutting through bone and the removal of bone, bone spurs or ligament. Ultrasonic surgical devices, employing an ultrasonically excited cutting blade, have demonstrated precision and accuracy in bone surgeries, allowing surgeons to carry out bone cutting in difficult-to-reach surgical sites. For surgical procedures in a confined space, a small surgical device has benefits, but for ultrasonic devices this results in a reduced amount of piezoceramic material in the transducer. This paper provides insights into the trade-offs between the volume of piezoceramic material, location of the piezoceramic rings, resonant frequency and the achievable vibration amplitude. Bolted Langevin-style Transducers (BLT) are adopted for this study. Experimental results show that a similar level of vibration displacement can be achieved at a much lower input voltage with a higher quantity of piezoceramic elements. However, the associated nonlinear behaviour is exacerbated. Locating the piezoceramic elements at the longitudinal displacement node is critical, in order to maximise the ultrasonic energy transfer

    Tissue-Welding Device : Considerable Advantages for Spleen Surgery Based on Histological and Cardiorespiratory Investigation

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    Publisher Copyright: © 2022 Linda Gatiņa et al.During splenic surgery, it is important to control blood loss and the potential risk of cardiac arrhythmia. The best way to prevent complications from surgery is to use the appropriate surgical devices; however, there is no guideline for the use of specific surgical devices for spleen incision. Therefore, the aim of this research was to compare the interactions of various surgical devices with spleen tissue, their cardiorespiratory effects during incision, and subsequent spleen surgical wound healing. A total of 75 rabbits were included in the study. CO2 laser (n = 15), radiofrequency device (n = 15), electrocoagulator (n = 15), tissue-welding device (n = 15), and scalpel (n = 15) were used to make incisions in rabbits' spleens. Spleen biopsies of the incision area were taken from each animal at the day 0, 7, and 14 after surgery. Contactless thermography was performed during surgery. Suturing was not used after incision with the tissue-welding device, but incisions made by other surgical devices were sutured. The results showed that the width of spleen necrosis differed significantly between the various surgical devices used on spleen tissues. There was a positive, strong, and linear association between necrosis width and the tissue temperature of cutting edges. Significant increases in the heart rate were observed during spleen surgery performed with laser, scalpel, and radiofrequency devices. In conclusion, the tissue-welding device confers a significant advantage in spleen surgery, as there is neither a need for sutures nor a significant deviation in the heart rate.publishersversionPeer reviewe

    GROSS POSITIONING DEVICE AND RELATED SYSTEMS AND METHODS

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    Disclosed herein are gross positioning systems for use with robotic surgical devices to provide gross positioning of the robotic surgical devices. The gross positioning systems have a base, a first arm link operably coupled to the base, a second arm link operably coupled to the first arm link, a third arm link operably coupled to the second arm link, and a slidable coupling component slidably coupled to the third arm link

    ROBOTIC SURGICAL DEVICES , SYSTEMS , AND RELATED METHODS

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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. Certain embodiments include various modular medical devices for in vivo medical procedures

    Surgical Applications of Compliant Mechanisms:A Review

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    Current surgical devices are mostly rigid and are made of stiff materials, even though their predominant use is on soft and wet tissues. With the emergence of compliant mechanisms (CMs), surgical tools can be designed to be flexible and made using soft materials. CMs offer many advantages such as monolithic fabrication, high precision, no wear, no friction, and no need for lubrication. It is therefore beneficial to consolidate the developments in this field and point to challenges ahead. With this objective, in this article, we review the application of CMs to surgical interventions. The scope of the review covers five aspects that are important in the development of surgical devices: (i) conceptual design and synthesis, (ii) analysis, (iii) materials, (iv) maim facturing, and (v) actuation. Furthermore, the surgical applications of CMs are assessed by classification into five major groups, namely, (i) grasping and cutting, (ii) reachability and steerability, (iii) transmission, (iv) sensing, and (v) implants and deployable devices. The scope and prospects of surgical devices using CMs are also discussed

    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
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