Initial realisation of a multichannel, non-linear PatLoc gradient coil
نویسندگان
چکیده
Spatial encoding using non-bijective, curvilinear magnetic fields [1] has been introduced to overcome present limitations of gradient performance due to safety limitations from peripheral nerve stimulation (PNS). These PatLoc(parallel acquisition technique using localized gradients) fields allow for higher ΔBmax/dt, and therefore faster imaging while staying below the limit of PNS. PatLoc fields may also be adapted to the subjects or organs anatomy, as it is not restricted to rectilinear data acquisition. For practical realisation in cylindrical geometry at least two fields are required, providing two gradients, one in radial and one in circumferential direction to retain some image reconstruction properties. As a continuous circumferential gradient is physically not realizable, a concept of using multipolar fields for spatial encoding was proposed [2]. It is most promising to use this gradient system as a head gradient set. For easy implementation this first functional model is designed for an animal MRI system. This abstract presents the first built gradient coil.
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