Thermally adjustable surgical tools include a conductor and a ferromagnetic material. The ferromagnetic material may be quickly heated when subjected to high frequency alternating current through the conductor. The ferromagnetic material may also cool rapidly because of its relatively low mass and the small thermal mass of the conductor. The thermally adjustable surgical tools may be used to sculpt, melt, break and/or remove biological material. The thermally adjustable surgical tools may also include balloon catheters which can heat fluid to thereby treat biological material.