Some implementations provide a method for modulating excitable tissue in a body of a patient, the method including: placing a wireless implantable stimulator device at a target site in the patient's body, the stimulator device including one or more electrodes; reconfiguring the wireless implantable stimulator device to form an enclosure that substantially surrounds the excitable tissue at the target site with the electrodes on the inside of the enclosure and facing the nerve; and causing electrical impulses to be delivered to the electrodes on the wireless implantable stimulator device such that neural modulation is applied to the excitable tissue substantially surrounded by the enclosure.