Diffusion-weighted MRI and PET–CT in the follow up of chronic periaortitis

Aim of the present study is to compare magnetic resonance imaging (MRI) and positron emission tomography (PET) parameters in the follow up of chronic periaortitis (CP), with a focus on changes in the apparent diffusion coefficient (ADC) and standardized uptake values (SUV). 127 patients with CP were treated in our urology between 2007 and 2017. We identified 14 patients with parallel abdominal MRI and PET–CT examinations before therapy and in the follow up resulting in a total of 56 examinations. Relative contrast uptake and diffusion-weighted MRI parameters were compared to SUV in the corresponding PET–CT examinationsand laboratory infection markers. All examined MRI and PET–CT parameters showed significant changes between basis and follow-up examinations. Median ADC values increased significantly (p