A medical probe assembly and method for ablating tissue using radio frequency energy. The medical probe assembly includes an elongated shaft, a needle electrode array, and a hinged handle. The handle has a collar, which when in the up position covers the hinge so that the device can be used as a conventional medical probe. When the collar is in the down position the hinge is exposed, and the handle can be bent to reduce its overall height. With this reduced height the probe can be used while a patient is lying in a CT scanner or an MRI chamber. Therefore, the surgeon can monitor the ablation during the procedure, and thus avoid unnecessary damage to the surrounding healthy tissue on the one hand, and insufficient ablation of the diseased tissue on the other hand. An alternate embodiment uses a flexible handle instead of a hinged one.