Human cardiac imaging at 3 T using phased array coils

Using a two-element phased array receiver coil, single breath-hold, ECG gated cardiac images of signal-to-noise ratios up to 130 and contrast-to-noise ratios exceeding 35 between myocardium and blood were recorded at 3 T. At several locations within the myocardium, T*(2) and B(0) inhomogeneity were determined. Because of shorter T*(2) times and larger B(0) inhomogeneities attributable to enhanced susceptibility effects, real-time cardiac imaging, the use of spiral scans, and echo planar imaging are expected to be considerably more difficult at 3 T.

Performance and use of current sheet antennae for RF-hyperthermia of a phantom monitored by 3 tesla MR-thermography

Several MR-compatible current sheet antennae (CSA) of different height (h) (16 cm (l) x 8 cm (w) x 1-5 cm (h)) were built for simulated RF (96 MHz) hyperthermia of a medium-sized (12l) tissue-equivalent phantom inside a 3 tesla whole body tomograph. Prior to use, efficiencies of the CSA were determined by network analysis and by calorimetry. Depending on the height h of the CSA and on the thickness d(bolus) of the water bolus used for RF-coupling of the CSA to the lossy medium, their efficiency varied between 20-70% and the CSA with h = 3 cm was selected for simulated RF hyperthermia. During heating, spatial temperature distributions (20-42 degrees C) of five slices (voxel size 2 x 2 x 10mm(3)) were recorded intermittently within 4 s/slice by measuring the temperature dependent shift of the (1)H resonance frequency (125.32 MHz). A phased array consisting of two identical CSA produced distinctly different spatial temperature distributions at 0 and 180 degrees phase difference between both RF channels feeding the antennae. Within a one-dimensional heat diffusion model, the specific absorption rate (SAR) of the electromagnetic wave generated by a single antenna was deduced from the experimental data resulting in a penetration depth (1/e(2)) of approximately 4 cm.

Current CONtrolled Transmit And Receive Coil Elements (CONTAR) for Parallel Acquisition and Parallel Excitation Techniques at High-Field MRI

A novel intrinsically decoupled transmit and receive radio-frequency coil element is presented for applications in parallel imaging and parallel excitation techniques in high-field magnetic resonance imaging. Decoupling is achieved by a twofold strategy: during transmission elements are driven by current sources, while during signal reception resonant elements are switched to a high input impedance preamplifier. To avoid B(0) distortions by magnetic impurities or DC currents a resonant transmission line is used to relocate electronic components from the vicinity of the imaged object. The performance of a four-element array for 3 T magnetic resonance tomograph is analyzed by means of simulation, measurements of electromagnetic fields and bench experiments. The feasibility of parallel acquisition and parallel excitation is demonstrated and compared to that of a conventional power source-driven array of equivalent geometry. Due to their intrinsic decoupling the current-controlled elements are ideal basic building blocks for multi-element transmit and receive arrays of flexible geometry.

A randomized controlled trial of acupuncture and receptive music therapy for sleep disorders in the elderly-ELAMUS: study protocol

BACKGROUND

Globally, the demographic shift towards an aging population leads to significant challenges in healthcare systems, specifically due to an increasing incidence of multimorbidity resulting in polypharmacy among the elderly. Simultaneously, sleep disorders are a common complaint for elderly people. A treatment with pharmacological therapies often leads to side effects causing a high potential for dependency. Within this context, there is a high need to explore non-pharmacological therapeutic approaches. The purpose of this study is to evaluate the effectiveness of acupuncture and music therapy, both individually and combined as a multimodal therapy, in the treatment of sleep disorders in individuals aged 70 years and older.

METHODS

We conduct a confirmatory randomized controlled trial using a two-factorial study design. A total of n = 100 elderly people receive evidence-based standard care information for age-related sleep disorders. Beyond that, patients are randomly assigned into four groups of n = 25 each to receive acupuncture, receptive music therapy with a monochord, multimodal therapy with both acupuncture and music therapy, or no further therapy. The study's primary outcome measurement is the improvement in sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI) (global score), at the end of intervention. Additionally, depression scores (Geriatric Depression Scale), health-related quality of life (Short-Form-Health Survey-12), neurovegetative activity measured via heart rate variability, and safety data are collected as secondary outcomes. Using a mixed-methods approach, a qualitative process evaluation will be conducted to complement the quantitative data.

DISCUSSION

The study is ongoing and the last patient in is expected to be enrolled in April 2024. The results can provide valuable insights into the effectiveness of non-pharmacological interventions for sleep disorders among the elderly, contributing to a more personalized and holistic approach in geriatric healthcare.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS00031886).