Abstract: A multiple lumen catheter assembly having at least two catheters separate and independent from each other along at least a portion of their lengths, and that can be selectively joined together to change the separation distances between the catheters by of a connecting means.

Abstract: Cryosurgical apparatus includes an elongate cryoprobe having a cooling portion and an electrically conductive first portion in the region of the cooling portion. A removable sheath having an electrically conductive second portion is received on the cryoprobe with its electrically conductive second portion spaced from the electrically conductive first portion of the cryoprobe. Electrical insulation is interposed between the first portion and the second portion. Coolant material supplied to the cryoprobe produces tissue freezing in the region of the cooling portion. Electromagnetic energy supplied to either the first portion or the second portion, while the other of such first portion or second portion is connected to ground, provides selective heating in tissue surrounding an iceball produced by the cooling portion to control the configuration of the iceball.