Tactile Feedback for Artery Detection in Minimally Invasive Robotic Surgery –Preliminary Results of a New Approach

Minimally invasive robotic surgery (MIRS) entails total absence of haptic feedback due to the spatial separation of patient and surgeon. In conventional surgery, however, palpation to detect superficial arteries by a slight pulsation is an important, commonly applied, and security-relevant procedure. Therefore, an ultrasound based unidirectional sensor for MIRS was developed feeding back kinesthetic impulses to the surgeon-sided haptic input device

Detection of small UAS with W-band radar

The detection and defense of Unmanned Aerial Systems (UAS) is becoming increasingly important for the protection of public and private areas. The low cost of micro- and mini-drones, the easy handling, and a considerable payload make them an excellent tool for unwanted surveillance or attacks. The platforms can be equipped with all kind of sensors or, in the worst case, with explosive devices. On the other hand, the size, material, and flight characteristics of these micro aerial vehicles is not advantageous for their detection with any kind of sensor. Therefore, great efforts are needed to ensure reliable detection, localization, tracking, and classification of the low, small, and slow systems. In this paper, we demonstrate that W-band radar is capable of detecting small drones in realistic scenarios, including 3D-localization. In addition, classification of a target is possible by means of Micro-Doppler analysis. As a matter of fact, improved information can be achieved when combining the radar with supplementary sensors, like electrooptical, infrared, and acoustical. However, in challenging scenarios, e.g. smoky, foggy, or loud environments, most sensors are overtaxed and the potential of radar can be fully exploited. Under certain conditions, radar would be the only applicable alternative for a dependable detection of UAS. FMCW-radar (Frequency Modulated Continuous Wave) in the millimeter wave regime is typically very compact, lightweight and requires only low power. Thus, it is easily deployable in various surveillance scenarios and safety applications. The range coverage of several hundred meters is, in the majority of cases, sufficient and the available update rates are far beyond the requirements of drone detection

Effectiveness of botulinum toxin treatment for upper limb spasticity after stroke over different ICF domains: a systematic review and meta-analysis

Objective: To provide a comprehensive overview of reported effects and scientific robustness of botulinum toxin (BoNT) treatment regarding the main clinical goals related to poststroke upper limb spasticity, using the International Classification of Functioning, Disability and Health. Data Sources: Embase, PubMed, Wiley/Cochrane Library, and Ebsco/CINAHL were searched from inception up to May 16, 2018. Study Selection: We included randomized controlled trials comparing upper limb BoNT injections with a control intervention in patients with a history of stroke. A total of 1212 unique records were screened by 2 independent reviewers. Forty trials were identified, including 2718 patients with history of stroke. Data Extraction: Outcome data were pooled according to assessment timing (ie, 4-8wk and 12wk after injection), and categorized into 6 main clinical goals (ie, spasticity-related pain, involuntary movements, passive joint motion, care ability, arm and hand use, and standing and walking performance). Sensitivity analyses were performed for the influence of study and intervention characteristics, involvement of pharmaceutical industry, and publication bias. Data Synthesis: Robust evidence is shown for the effectiveness of BoNT in reducing resistance to passive movement, as measured with the (Modified) Ashworth Score, and improving self-care ability for the affected hand and arm after intervention (P<.005) and at follow-up (P<.005). In addition, robust evidence is shown for the absence of effect on arm-hand capacity at follow-up. BoNT was found to significantly reduce involuntary movements, spasticity-related pain, and caregiver burden, and improve passive range of motion, while no evidence was found for arm and hand use after intervention. Conclusions: In view of the robustness of current evidence, no further trials are needed to investigate BoNT for its favorable effects on resistance to passive movement of the spastic wrist and fingers, and on self-care. No trials are needed to further confirm the lack of effects of BoNT on arm-hand capacity, whereas additional trials are needed to establish the suggested favorable effects of BoNT on other body functions, which may result in clinically meaningful outcomes at activity and participation levels

Increased high-frequency heart rate variability during insulin-induced hypoglycaemia in healthy humans

Despite causing sympathetic activation, prolonged hypoglycaemia produces little change in HR (heart rate) in healthy young adults. One explanation could be concurrent parasympathetic activation, resulting in unchanged net effects of autonomic influences. In the present study, hypoglycaemic (2.7 mmol/l) and normoglycaemic (4.7 mmol/l) hyperinsulinaemic clamp studies were performed after normoglycaemic baseline clamp periods with 15 healthy volunteers (seven male; mean age, 27 years) on two occasions in a randomized single-blind cross-over design. Non-invasive indices of cardiac autonomic activity and hormones were measured at baseline and 1 h after the beginning of hypoglycaemia or control normoglycaemia. Plasma insulin levels and mean HR were similar during both conditions. During hypoglycaemia, there was a 485% increase in plasma adrenaline (epinephrine). A shortening of the pre-ejection period by 45% suggested strong sympathetic cardiac activation. High-frequency (0.15-0.45 Hz) HRV (HR variability) increased, indicating a concomitant increase in parasympathetic tone. Thus, during hypoglycaemia-induced sympathetic cardiac activation in healthy adults, parasympathetic mechanisms are involved in stabilizing mean HR

Double tracer gas single-breath washout: reproducibility in healthy subjects and COPD

The applicability and interpretation of inert tracer gas washout tests is hampered by the lack of feasible protocols and reproducibility data. We assessed feasibility, variability and reproducibility of a new easy to perform double tracer gas (DTG) single-breath washout (SBW) test and compared this with conventional nitrogen washouts. In 40 healthy nonsmokers and 20 patients with stable chronic obstructive pulmonary disease (COPD), we performed three N2 vital capacity SBWs, three N2 multiple-breath washouts and three tidal DTG-SBW tests. Follow-up was after 1 week, 1 month and 6 months. Main outcomes were the lung clearance index (LCI) (N2 multiple-breath washout), slope of phase III (dN2) (N2 vital capacity SBW) and slope of phase III (SIIIDTG) (DTG-SBW). In healthy subjects, mean±sd LCI at baseline was 6.94±0.61, dN2 0.99±0.42% N2 per litre and SIIIDTG -0.206±0.108 g·mol(-1)·L(-1). In COPD, LCI and dN2 were significantly higher (LCI 12.23±2.67, dN2 7.43±5.38% N2 per litre; p<0.001) and SIIIDTG significantly steeper (-0.653±0.428 g·mol(-1)·L(-1), p<0.001). Reproducibility was high for main outcome parameters: the intraclass correlation coefficient over 6 months was 0.77 (0.86 in COPD) for LCI, 0.82 (0.89) for dN2 and 0.83 (0.93) for SIIIDTG. The tidal DTG-SBW is a reproducible test in healthy and COPD subjects that seems attractive for use in routine clinical settings

A simple method to reconstruct the molar mass signal of respiratory gas to assess small airways with a double-tracer gas single-breath washout

For the assessment of small airway diseases, a noninvasive double-tracer gas single-breath washout (DTG-SBW) with sulfur hexafluoride (SF6) and helium (He) as tracer components has been proposed. It is assumed that small airway diseases may produce typical ventilation inhomogeneities which can be detected within one single tidal breath, when using two tracer components. Characteristic parameters calculated from a relative molar mass (MM) signal of the airflow during the washout expiration phase are analyzed. The DTG-SBW signal is acquired by subtracting a reconstructed MM signal without tracer gas from the signal measured with an ultrasonic sensor during in- and exhalation of the double-tracer gas for one tidal breath. In this paper, a simple method to determine the reconstructed MM signal is presented. Measurements on subjects with and without obstructive lung diseases including the small airways have shown high reliability and reproducibility of this method