Implantable marker and a method of implanting markers

Abstract

Implantable magnetic markers (seeds) provide a higher degree of flexibility and convenience. The magnetic field that a marker provides is determined by the magnetic properties of the materials used and the dimensions of the marker—in general, a larger marker is easier to locate. Larger diameter markers may be used, but they should be much smaller than the average tumor size if they are to provide a useful degree of localization. An implantable magnetic marker is provided with two or more magnetic elements comprising permanent magnets connected by a mechanical connector to resiliently retain a first orientation when deployed and a second orientation before and/or during implantation. This allows complex magnetic configurations to be implanted, while retaining a simplified implantation method independent of the number of magnetic elements used. The transverse extent of the magnetic marker may be significantly reduced for implantation, allowing smaller needle diameters (smaller needle gauges) to be used or a larger number of smaller marker elements. This also allows significantly less longitudinal extents to be used. In addition, the two or more magnetic elements may be aligned to increase the transverse extent by increasing the transverse extent after implantation. This may increase detectability.