A medical device has a flexible elongated body, ahandle connected to the elongated body, at least onespine connected to the elongated body, and a flexiblesheet attached to the at least one spine. The flexiblesheet has a plurality of electrodes thereon, wherein theflexible sheet and the plurality of electrodes define amapping assembly for mapping electrical information intissue, and wherein the at least one spine and theflexible sheet is movable from a collapsed configurationto a deployed configuration.
