Nuclear magnetic resonance apparatus

In a nuclear magnetic resonance apparatus an RF coil arrangement comprises two or more separable parts adapted to be assembled around the body to be examined to form the coil arrangement. The parts are suitably arranged to be electrically connected, when assembled, by adjustable coupling means so that the volume embraced by the coil arrangement may be adjusted. The invention enables the coil arrangement to be positioned more closely around a body being examined, for example a patient's neck or head, than is possible with conventional, unitary, tubular coil arrangements. For examination of a patient's head, a window may be formed by transparent or cut away portions of the RF coil arrangement. (author)