Abstract: The disclosure relates to methods of imaging a portion of a body vessel using magnetic resonance imaging (MRI), methods of performing interventional medical treatment under MRI, interventional medical devices, such as wire guides, useful in performing treatment under MRI, and methods of making interventional medical devices. A method of imaging a portion of a body vessel of a patient using MRI includes advancing through a body vessel an end of a wire guide comprising a continuous metal core member and a continuous jacket disposed over the entire core member through a body vessel and scanning the portion of the patient that is positioned within an MRI scanner and that includes a portion of the body vessel within which the end of the wire guide is disposed. A secondary medical device, such as a catheter, can be disposed over the wire guide and manipulated in the method.

Abstract: Example interventional medical devices useful in performing treatment under magnetic resonance imaging and related methods are described. A method of making a medical device useful in procedures performed under magnetic resonance imaging includes selecting a first material, selecting a second material that is different from the first material, incorporating the second material into a portion of the first material, and forming the first and second materials into a desired structure to form the interventional medical device. The second material can be melted and disposed in a void formed in the first material, and work hardened to increase magnetic susceptibility.

Abstract: A medical device (10) such as a radio frequency dilator sheath for separating an encapsulated elongated structure (11) such as an electrical cardiac lead implanted in biological tissue (12) such as a vessel leading to or from a patient's heart. The radio frequency dilator sheath includes inner and outer coaxial dilator sheaths (13 and 28) with respective beveled distal ends (18 and 36) for mechanically loosening and separating encapsulating tissue from an implanted electric cardiac lead. The beveled distal end of the inner sheath is truncated to form a transverse face or surface (89) that is approximately perpendicular to the longitudinal axis of the sheath. Electrical conductors (16 and 17) are positioned about the distal end (14) and passage (15) of the inner dilator sheath.