1. A method for using high intensity focused ultrasound (HIFU) to achieve a desired therapeutic effect associated with selected spinal or peripheral nerves in a patient, comprising the steps of: (a) determining an appropriate treatment site associated with the selected spinal or peripheral nerves; (b) selecting a dose of HIFU required to achieve the desired therapeutic effect; (c) positioning an HIFU therapy probe external to a body, such that a focal point of the HIFU therapy probe is disposed at or adjacent to the treatment site; (d) verifying that the focal point of the externally positioned HIFU therapy probe is properly positioned relative to the treatment site by (i) using ultrasound imaging to obtain an ultrasound image of the treatment site and (ii) energizing the HIFU therapy probe at a power level that is insufficient to induce damage at the treatment site, but is sufficient to enable the focal point of the HIFU therapy probe to be visualized in the ultrasound image, and if not, repositioning the HIFU therapy probe until the focal point of the HIFU therapy probe is properly positioned relative to the treatment site, (e) energizing the HIFU therapy probe to provide the dose of HIFU required to achieve the desired therapeutic effect; and (f) using ultrasound imaging to obtain an ultrasound image of the treatment site during therapy.