RESUMEN
An RF coil, made by twisting a conventional wire loop, was tuned to form an extended sensor to provide an effective method of showing the track of a catheter. A twisted-pair coil can be made small enough in diameter to pass through needles in common clinical use. The coil has a very small field of view and in transmit/receive operation has minimal effect on the magnetization of the surrounding tissue.
Asunto(s)
Cateterismo/instrumentación , Imagen por Resonancia Magnética/instrumentación , Diseño de Equipo , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Modelos Teóricos , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Sensibilidad y EspecificidadRESUMEN
Divergencies between chemical shift measurements of temperature and directly measured values using optical sensors have been studied in vivo in human peripheral muscle with the assistance of a variety of experimental and theoretical techniques. These include the modelling of both thermal and susceptibility changes using two- and three-dimensional finite element methods, as well as the use of multi-wavelength near-infrared observations. The conclusion of these studies is that a simple temperature calibration is not accessible, with results affected by the complex response of the tissue itself.