Patent attributes
Implantable materials may be used as spacers for separating tissues to reduce a dose of radioactivity received by one of the tissues. Applications include introducing a hydrogel spacer to a position between a first tissue location and a second tissue location to increase a distance between the first tissue location and the second tissue location, Further, there may be a step of administering a dose of radioactivity to at least the first tissue location or the second tissue location and/or a step of visualizing margins of the hydrogel spacer. A hydrogel spacer may comprise a polysaccharide and a radioopaque agent and may be used for fiducial marking.