Equipotential projection-based magnetic resonance electrical impedance tomography and experimental realization

In this study, a direct, fast image reconstruction algorithm, based on the fact that equipotential lines are perpendicular to current lines in a volume conductor, is proposed for magnetic resonance electrical impedance tomography (MR-EIT). The proposed technique is evaluated both on simulated and measured data for conductor and insulator objects

The impact of daily troponin I and D-dimer serum levels on mortality in COVID-19 pneumonia patients

Background: Coronavirus disease 2019 (COVID-19) is an infection resulting in very high morbidity and mortality rates globally. Limited data are available on the cardiovascular manifestations in these patients. The aim of this study was to analyse the daily troponin I and D-dimer levels and their impact on the need for intensive care and on mortality rates of COVID-19-infected patients

What adds Valsalva maneuver to hemostasis after Trendelenburg's positioning during thyroid surgery?

WOS: 000423437800003PubMed ID: 29142831Background: Bleeding after thyroidectomy is life-threatening. The aim of the study was to evaluate whether controlling of further bleeding with Valsalva maneuver following Trendelenburg's positioning has an impact on hemostasis. Methods: This prospective study included 68 consecutive patients undergoing thyroidectomy. Study protocol consisted of performing manual intra-abdominal pressure increase and Valsalva maneuver to check hemostasis and treating any bleeding point identified, after Trendelenburg's positioning. All identified bleeding points and treatments were recorded. Results: Total number of bleeding points identified in Trendelenburg's tilt was 49, while it was 41 when using Valsalva maneuver. Abdominal pressure increase, carried out before Valsalva maneuver, identified 14 bleeding points, which was less than bleeding after Trendelenburg's positioning and Valsalva maneuver (P<0.05). All bleeding points, except 1 for Trendelenburg's positioning and 1 for Valsalva maneuver, were minor (<2 mm). Only 4.4% bleeding vessels required ties or stitching. Conclusions: Valsalva maneuver helps to detect any further bleeding following Trendelenburg's positioning

Quantitative proton magnetic resonance spectroscopy in presence of sidebands

We perform Proton Magnetic Resonance Spectroscopy (MRS) without water suppression in contrast to traditional water-suppressed MRS. The preserved water signal can be used as a reference for the absolute quantification of metabolites, reducing the total measurement time. However, the non-water-suppressed spectra can be contaminated by gradient-induced frequency modulations resulting in sidebands in the spectrum. Sidebands may obscure the metabolite resonances of interest, thereby rendering the spectral analysis and quantification problematic. To this end, we present a correction technique to remove sidebands. The proposed method utilizes the phase of an external reference of single resonance to observe the time-varying the static field fluctuation induced by gradient-vibrations then deconvolves this phase contamination from the desired signal obtained under the same experimental conditions. The method is evaluated by phantom and in vivo measurements