RF MARKER SIMULATION MODEL FOR INTERVENTIONAL MRI APPLICATIONS

Öz

RF MARKER SIMULATION MODEL FOR INTERVENTIONAL MRI APPLICATIONS Compared to the other imaging modalities Magnetic Resonance Imaging (MRI) system has many advantages. There is a great demand to carry out interventional cardiovascular procedures under MRI scanner. However, the lack of visible markers and MRI compatible interventional instruments and devices, is the main problem for realizing clinical applications with MRI guidance. In order to provide widespread usage of MRI for endovascular operations, commercial catheters and guidewires must be manufactured by considering many performance criteria including visualization, miniaturization, flexibility and safety. In this study, an orientation independent simulation model was developed and validated to obtain a reliable method for evaluating the designed RF marker structures in a MRI environment. Utilized RF coil designs have similar size and properties with former constructed clinical grade MRI compatible RF markers in experimental works [1]. Finite Element Method (FEM) simulations were carried out for different RF coil designs to make the computational analysis of their electrical and magnetic characteristics by using COMSOL Multiphysics program. By delineating an approved simulation platform of a MRI environment, various different designs of RF marker prototypes can be compared between each other in many aspects, instead of realizing these models. Proposed simulation platform enables a convenient facility to determine various parameters of micro coils that have significant effects on visibility and safety performance of the candidate designs including signal to noise ratio (SNR) and Quality (Q) factor, RF induced heating and specific absorption rate (SAR).

Anahtar Kelimeler

• Interventional MRI

Kaynakça

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