Device for forming holes in tissue

摘要

A surgical instrument (10) for creating holes of a predetermined diameter and depth in body tissue comprises a tubular catheter (12) having a compression spring (20) affixed at its dital end and attached to the distal end of that spring is a tissue ablating device (22) which may, for example, comprise an electrosurgical monopolar or bipolar electrode that is connected by conductors extending through the lumen (18) of the catheter to an electrosurgical generator at its proximal end. When the instrument is brought in contact with target tissue with a force sufficient to compress the coils of the spring against one another and then ablating energy applied, tissue will be removed as the spring is allowed to expand out to its uncompressed length. The depth of the hole thus created is equal to the difference (d) between the lengths of the spring when compressed and uncompressed. If desired, a suitable drug can be delivered into the thus created hole via a lumen in the catheter.