An intraurethral catheter shaft comprises a plurality of lumens extending between a first end and a second end of the shaft. An antenna lumen has a generally circular cross-sectional surface area and is positioned nearer a first outer surface than a second outer surface of the catheter shaft. A first...http://www.google.es/patents/US5628770?utm_source=gb-gplus-sharePatente US5628770 - Devices for transurethral thermal therapy
