Effective November 1, 2012, AIM Specialty Health^SM (AIM), an independent company, will implement updated imaging clinical guidelines as a result of their 2012 guideline review process. The process to request prior authorization is not affected; however, there are other important updates that will affect the following diagnostic imaging services: computed tomography (CT) or magnetic resonance imaging (MRI) of the spine CT or MRI of the brain computed tomography angiography (CTA) of the chest myocardial perfusion imaging (MPI) For specific details on the changes made to these guidelines, please review the article posted to our Medical Policy website which outlines each of the changes and provides the clinical rationale and relevant medical literature. Also effective November 1, 2012, in support of AIM?s existing guideline on "Simultaneous Ordering of Multiple Imaging Tests," requests that involve multiple examinations of contiguous body parts that cannot be approved prior to AIM physician review will require a peer-to-peer conversation. If the AIM physician reviewer cannot reach the ordering provider, none of the multiple exams requested will be approved. These changes will be reflected in the clinical guidelines, which will be available on the AIM website once they go into effect.