Ablation apparatus is provided. The apparatus includesan ablation electrode shaped to define a cavity thereof, andcomprising a metallic distal face that is shaped to define aplurality of apertures. A fluid-delivery channel isconfigured to deliver fluid to the apertures. At least oneultrasound transducer is disposed within the cavity of theablation electrode, the transducer being configured totransmit an ultrasound wave through the apertures. Otherembodiments are also described.
