Phased-array coil

Characterization of Phased Array Coils for Diagnostic Magnetic Resonance Imaging Systems... 

The MR imaging protocol at intermediate or high-field strength includes the use of a pelvic phase array coil, 3-6 h fasting prior to the examination, and an intra-muscular injection of an anti-peristaltic agent, such as 20 mg of Buscopan (butylscopalamine,Scher-... 

The body phased-array coils available today allow imaging of the entire abdomen with high resolution and should be used whenever available to assess retroperitoneal lymph nodes in addition to evaluating the regional pelvic lymph nodes in all MRl examinations of a primary pelvic tumor. In patients with cervical or endometrial cancer, the demonstration of suspicious retroperitoneal lymph nodes is important for therapeutic planning in patients scheduled for postoperative radiotherapy. 

Note A body phased-array coil is recommended for acquisition of high-resolution TSE/FSE sequences and breath-hold sequences. Recommended for high-resolution imaging of pelvic lymph nodes (with administration of spasmolytic agent)... 

With conventional MR imaging techniques, lymph nodes are visualized vdien they have a size of at least 1.0-1.5 cm [10]. Optimized imaging techniques (body phased-array coil, 512 matrix, 3D acquisition) or state-of-the-art spiral or multislice CT scanners depict lymph nodes as small at about 3-5 mm [7,8]. These techniques usually allow good evaluation of the lymph nodes adjacent to the straight great vessels (Fig. 15.1). 

The achievement of high resolution images is improved by the use of a phased array coil, in which the hips and pelvis are in the centre of the field of view. Enhancement with the paramagnetic contrast (Gadolinium based compound) depends on the clinical problem. A typical imaging protocol is shown in Table 13.1 (Dillon et al. 2005). 

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