305 research outputs found

    Real-Time Imaging System using a 12-MHz Forward-Looking Catheter with Single Chip CMUT-on-CMOS Array

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    Forward looking (FL) imaging catheters would be an important tool for several intravascular ultrasound (IVUS) and intracardiac echocardiography (ICE) applications. Single chip capacitive micromachined ultrasonic transducer (CMUT) arrays fabricated on front-end CMOS electronics with simplified electrical interconnect have been previously developed for highly flexible and compact catheters. In this study, we present a custom built real time imaging system utilizing catheters with single chip CMUT-on-CMOS arrays and show initial imaging results. The fabricated array has a dual-ring structure with 64 transmit (Tx) and 56 receive (Rx) elements. The CMUT arrays fit on a 2.1 mm diameter circular region with all the required front-end electronics. The device operates at 12 MHz center frequency and has around 20 V collapse voltage. The single-chip system requires 13 external connections including 4 Rx channels and power lines. The electrical connections to micro cables in the catheter are made from the top side of the chip using polyimide flex tapes. The device is placed on a 6-Fr catheter shaft and secured with a medical grade silicon rubber. For real time data acquisition, we developed a custom design FPGA based imaging platform to generate digital control sequences for the chip and collect RF data from Rx outputs. We performed imaging experiments using wire phantoms immersed in water to test the real time imaging system. The system has the potential to generate images at 32 fps rate with the particular catheter. The overall system is fully functional and shows promising image performance

    A high prevalence of cumulative trauma disorders in Iranian instrumentalists

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    BACKGROUND: Cumulative trauma disorders (CTDs) are common in musicians and their prevalence has been the subject of a number of studies in most western countries. Such studies are scarce in developing countries despite the possibility that CTDs may have a different prevalence in these countries, especially when considering traditional musical instruments and different methods of playing. Although not formally studied before, according to our experience the prevalence of CTDs seemed to be high among Iranian instrumentalists. We proposed this study to determine the prevalence of CTDs in amateur music students playing one of the two traditional Iranian instruments: Daf and Setar. METHODS: In a prospective cross sectional study, we interviewed and examined the students of three music training centers in Iran. Seventy eight instrumentalists, who were playing Daf or Setar and twelve students who had not started playing yet were regarded as case and control groups respectively. Some of them also underwent electrodiagnostic studies. RESULTS: Forty-seven percent (17 of 36) of the Setar players and 57% (24 of 42) of the Daf players and fifty-three percent (41 of 78) of the instrumentalists as a whole had CTDs. None of them had carpal tunnel syndrome. CONCLUSIONS: Our study revealed that the prevalence of CTDs in Iranian instrumentalists was unusually high. In addition to age, other variables may be contributory. This needs to be further studied

    Differential modulation of corticospinal excitability during haptic sensing of 2-D patterns vs. textures

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    <p>Abstract</p> <p>Background</p> <p>Recently, we showed a selective enhancement in corticospinal excitability when participants actively discriminated raised 2-D symbols with the index finger. This extra-facilitation likely reflected activation in the premotor and dorsal prefrontal cortices modulating motor cortical activity during attention to haptic sensing. However, this parieto-frontal network appears to be finely modulated depending upon whether haptic sensing is directed towards material or geometric properties. To examine this issue, we contrasted changes in corticospinal excitability when young adults (n = 18) were engaged in either a roughness discrimination on two gratings with different spatial periods, or a 2-D pattern discrimination of the relative offset in the alignment of a row of small circles in the upward or downward direction.</p> <p>Results</p> <p>A significant effect of task conditions was detected on motor evoked potential amplitudes, reflecting the observation that corticospinal facilitation was, on average, ~18% greater in the pattern discrimination than in the roughness discrimination.</p> <p>Conclusions</p> <p>This differential modulation of corticospinal excitability during haptic sensing of 2-D patterns vs. roughness is consistent with the existence of preferred activation of a visuo-haptic cortical dorsal stream network including frontal motor areas during spatial vs. intensive processing of surface properties in the haptic system.</p

    “Am I also going to die, doctor?” A systematic review of the impact of in-hospital patients witnessing a resuscitation of another patient

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    Background: There is a growing interest in the impact of family-witnessed resuscitation. However, evidence about the effect of hospitalised patients witnessing other patients' resuscitations is limited. Aim: The aim of this systematic review is to explore the existing evidence related to the impact on patients who witness resuscitation attempts on other patients in hospital settings. Methods: The databases BNI, CINAHL, EMBASE, MEDLINE and PsycINFO were searched with the terms 'patient', 'inpatient', 'resuscitation', 'CPR', 'cardiopulmonary resuscitation' and 'witness'. The search strategy excluded the terms 'out-of-hospital', 'family' and 'relative'. The inclusion criteria were: studies related to patients exposed to a resuscitation attempt performed on another patient; quantitative and qualitative design; and physiological or psychological outcome measures. No limitations of date, language or settings were applied. Results: Five of the 540 identified studies were included: two observational studies with control groups and three qualitative studies with interviews and focus groups. Articles were published between 1968 and 2006 and were mostly rated to have a low quality of evidence. Quantitative results of the observational studies showed an increased heart rate in the study group witnessing a resuscitation (p = 0.05), increased systolic blood pressure (p &lt; 0.01) and increased anxiety (p &lt; 0.01). The qualitative studies highlighted the coping strategies adopted by exposed patients in response to witnessing resuscitation, including denial and dissociation. Conclusions: Our findings suggest that patients may find witnessing resuscitation to be a stressful experience. However, the evidence is sparse and mainly of poor quality. Further research is needed in order to better understand the impacts of patients witnessing a resuscitation of another patient and to identify effective support systems. © European Society of Cardiology 2017

    The Grasping Side of Odours

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    Background: Research on multisensory integration during natural tasks such as reach-to-grasp is still in its infancy. Crossmodal links between vision, proprioception and audition have been identified, but how olfaction contributes to plan and control reach-to-grasp movements has not been decisively shown. We used kinematics to explicitly test the influence of olfactory stimuli on reach-to-grasp movements. Methodology/Principal Findings: Subjects were requested to reach towards and grasp a small or a large visual target (i.e., precision grip, involving the opposition of index finger and thumb for a small size target and a power grip, involving the flexion of all digits around the object for a large target) in the absence or in the presence of an odour evoking either a small or a large object that if grasped would require a precision grip and a whole hand grasp, respectively. When the type of grasp evoked by the odour did not coincide with that for the visual target, interference effects were evident on the kinematics of hand shaping and the level of synergies amongst fingers decreased. When the visual target and the object evoked by the odour required the same type of grasp, facilitation emerged and the intrinsic relations amongst individual fingers were maintained. Conclusions/Significance: This study demonstrates that olfactory information contains highly detailed information able to elicit the planning for a reach-to-grasp movement suited to interact with the evoked object. The findings offer a substantia

    Specific orofacial problems experienced by musicians

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    Background: Patients who play musical instruments (especially wind and stringed instruments) and vocalists are prone to particular types of orofacial problems. Some problems are caused by playing and some are the result of dental treatment. This paper proposes to give an insight into these problems and practical guidance to general practice dentists. Method: Information in this paper is gathered from studies published in dental, music and occupational health journals, and from discussions with career musicians and music teachers. Results: Orthodontic problems, soft tissue trauma, focal dystonia, denture retention, herpes labialis, dry mouth and temporomandibular joint (TMJ) disorders were identified as orofacial problems of career musicians. Options available for prevention and palliative treatment as well as instrument selection are suggested to overcome these problems. Conclusions: Career musicians express reluctance to attend dentists who are not sensitive to their specific needs. General practitioner dentists who understand how the instruments impact on the orofacial structures and are aware of potential problems faced by musicians are able to offer preventive advice and supportive treatment to these patients, especially those in the early stages of their career

    Patient dose reduction during voiding cystourethrography

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    Voiding cystourethrography (VCUG) is a commonly performed examination in a pediatric uroradiology practice. This article contains suggestions on how the radiation dose to a child from VCUG can be made ‘as low as reasonably achievable–(ALARA). The pediatric radiologist should consider the appropriateness of the clinical indication before performing VCUG and utilize radiation exposure techniques and parameters during VCUG to reduce radiation exposure to a child. The medical physicist and fluoroscope manufacturer can also work together to optimize a pulsed-fluoroscopy unit and further reduce the radiation exposure. Laboratory and clinical research is necessary to investigate methods that reduce radiation exposures during VCUG, and current research is presented here
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