Tissue ablation systems and methods of using the same are disclosed. The tissue ablation systems can have an ultrasound ablation device connected to a catheter. The ultrasound ablation device can have a first conical reflector having a first reflective surface and a second conical reflector having a second reflective surface. The distance between the first and second conical reflectors can be adjusted, e.g., increased and/or decreased, to adjust the radial and/or longitudinal dimension of a focal zone from the device.
