PURPOSE To evaluate the effect of a composite radiofrequency (RF) pulse on saturation recovery (SR) myocardial T1 mapping using a 3T MR system. MATERIALS AND METHODS Phantom and in vivo studies were performed with a clinical 3T MR scanner. Accuracy and reproducibility of the SR T1 mapping using conventional and composite RF pulses were first compared in phantom experiments. An in vivo study w...

A radiofrequency electromagnetic field (RF-EMF) of 1800 MHz is widely used in mobile communications. However, the effects of RF-EMFs on cell biology are unclear. Embryonic neural stem cells (eNSCs) play a critical role in brain development. Thus, detecting the effects of RF-EMF on eNSCs is important for exploring the effects of RF-EMF on brain development. Here, we exposed eNSCs to 1800 MHz RF-...

In this work we tested viability, proliferation, and vulnerability of neural cells, after continuous radiofrequency (RF) electromagnetic fields exposure (global system for mobile telecommunications (GSM) modulated 900 MHz signal at a specific absorption rate (SAR) of 1 W/kg and maximum duration 144 h) generated by transverse electromagnetic cells. We used two cellular systems, SN56 cholinergic ...

Detection of non-Maxwellian electron energy distribution functions (EEDFs) by Langmuir probes in the presence of radiofrequency (RF) fluctuations in the plasma potential is possible if the probe is properly RF compensated. If the non-thermal electrons are created by wave acceleration, however, they usually are bunched at one phase of the RF. In this case, the usual method of forcing the probe t...

BACKGROUND The application of radiofrequency energy (RFE) has become widespread for surgical performed chondroplasty especially due to the anticipated sealing effect, however the safety of this procedure in the wrist remains unclear. The purpose of this study was to investigate the subchondral temperature during radiofrequency energy (RFE) application simulating chondroplasty in an arthroscopic...

Termocoagulation by radiofrequency (RF) is widely used for ablation of liver neoplasms. Recently, innovative uses of RF were proposed, as to assist liver resection, to help partial splenectomy, or to treat ruptured hepatocellular carcinoma. A 21 years old man was admitted for massive haemorrhage from a right thoraco-abdominal knife wound. Massive haemothorax was drained but arterial bleeding wa...

Local ablation therapy is considered as a conventional treatment option for patients with early stage hepatocellular carcinoma (HCC). Although radiofrequency (RF) ablation is widely used for HCC, the use of cryoablation has been increasing as newer and safer cryoablation systems have developed. The thermodynamic mechanism of freezing and thawing used in cryoablation is the Joule-Thomson effect....

Purpose: This work is based on the review of novel MRI methods for generating the longitudinal relaxation contrast, T1ρ, and the transverse relaxation contrast, T2ρ in the rotating reference frame regime at high and ultra-high magnetic fields. Clinical application of the T1ρ and T2ρ contrasts using the onor off-resonance spin-lock (SL) radiofrequency (RF) irradiation has been a challenging task...

A number of methods to improve excitation homogeneity in high-field MRI have been proposed, and some of these methods rely on separate control of radiofrequency (RF) coils in a transmit array. In this work we combine accurate RF field calculations and the Bloch equation to demonstrate that by using a sequence of pulses with individually optimized current distributions (i.e., an array-optimized ...

Introduction During the last years, several articles have been published on the effects of the radiofrequency fields (RF) of mobile telephony on sleep and EEG. These studies showed effects of GSM signals on the intensity of the alpha band of the EEG [1]. The ERNAM project lies within the scope of the 2010 RF research agenda of WHO. It will contribute to the understanding of the phenomena evoked...