To develop a 3D MR technique to simultaneously acquire proton multiparametric maps (T 1 , T 2 , and proton density) and sodium density weighted images over the whole brain. Methods:We implemented a 3D stack-of-stars MR pulse sequence which consists of interleaved proton ( 1 H) and sodium ( 23 Na) excitations, tailored slice encoding gradients that can encode the same slice for both nuclei, and simultaneous readout with different radial trajectories ( 1 H, full-radial; 23 Na, center-out radial).The receive chain of our 7T scanner was modified to enable simultaneous acquisition of 1 H and 23 Na signal. A heuristically optimized flip angle train was implemented for proton MR fingerprinting (MRF). The SNR and the accuracy of proton T 1 and T 2 were evaluated in phantoms. Finally, in vivo application of the method was demonstrated in five healthy subjects. Results:The SNR for the simultaneous measurement was almost identical to that for the single-nucleus measurements (<2% change). The proton T 1 and T 2 maps remained similar to the results from a reference 2D MRF technique (normalized RMS error in T 1 ≈ 4.2% and T 2 ≈ 11.3%). Measurements in healthy subjects corroborated these results and demonstrated the feasibility of our method for in vivo application. The in vivo T 1 values measured using our method were lower than the results measured by other conventional techniques.Conclusions: With the 3D simultaneous implementation, we were able to acquire sodium and proton density weighted images in addition to proton T 1 , T 2 , and B + 1 from 1 H MRF that covers the whole brain volume within 21 min.

To present a novel 3T 24-channel glove array that enables hand and wrist imaging in varying postures. Methods:The glove array consists of an inner glove holding the electronics and an outer glove protecting the components. The inner glove consists of four main structures: palm, fingers, wrist, and a flap that rolls over on top. Each structure was constructed out of three layers: a layer of electrostatic discharge flameresistant fabric, a layer of scuba neoprene, and a layer of mesh fabric. Lightweight and flexible high impedance coil (HIC) elements were inserted into dedicated tubes sewn into the fabric. Coil elements were deliberately shortened to minimize the matching interface. Siemens Tim 4G technology was used to connect all 24 HIC elements to the scanner with only one plug. Results:The 24-channel glove array allows large motion of both wrist and hand while maintaining the SNR needed for high-resolution imaging. Conclusion:In this work, a purpose-built 3T glove array that embeds 24 HIC elements is demonstrated for both hand and wrist imaging. The 24-channel glove array allows a great range of motion of both the wrist and hand while maintaining a high SNR and providing good theoretical acceleration performance, thus enabling hand and wrist imaging at different postures to extract kinematic information.