A whole volume neck coil for MRI includes an anterior and posterior saddle coil, the latter attached to a base. The anterior coil is held in an open framework, hinged against an extension tower attached to the base. The hinge axis is angled to the medial axis to provide greater entry area for the patient's head and shoulders. The extension tower also provides adjustment of the anterior coil toward and away from the base by means of a sliding carriage attached to the extension tower. The coils are passively decoupled from the RF excitation field by means of back-to-back diodes which insert a 'pole' forming network into the coils. A method of calculating the values of the network components is taught that accounts for significant diode junction capacitance.
NMR neck coil with passive decoupling