Guidance and monitoring of therapy is, in fact, very important for general clinical acceptance. Accurate targeting allows precise delivery of a therapeutic dose to the diseased tissue while avoiding exposure to the adjacent normal tissue. Monitoring allows one to assess the tissue response to the dose. Therefore, a practical guidance and monitoring system will contain the following features: (1) pretreatment imaging of the site and surrounding tissue to identify and target the exact location of the abnormal tissue, (2) imaging of the treatment site during therapy to provide dynamic localization of the abnormal tissue, and (3) post treatment imaging to map the treated region for follow-up and or continued therapy [1].