Emerging role of FDG-PET/CT as a diagnostic tool in detecting systemic and vascular inflammation in Psoriasis

Objectives Psoriasis is a systemic inflammatory disorder which is the most common autoimmune disease in the United States. Psoriasis primarily presents with skin lesions but may also affect other sites of the body; e.g. psoriasis arthritis which is seen in up to 30% of these patients. Furthermore, psoriatic patients have an increased risk of atherosclerosis and cardiovascular diseases as well as shorter life expectancy. There is a growing body of evidence that FDG-PET/CT is a sensitive and efficient noninvasive imaging modality for assessing inflammation and inflammatory diseases. This whole-body imaging modality is capable of detecting inflammation throughout the body, in organs such as skin, joints, entheses, liver, and vessel walls. Also, FDG and PET enables elaborate quantification of both regional and whole-body disease burden which has potential for prognostication (e.g. risk of cardiovascular events relative to vessel wall FDG uptake) as well as evaluation of treatment response (i.e. changes in global disease burden during treatment). In this educational exhibit we will review:

Methods i. Epidemiology and Pathology of psoriasis ii. Psoriasis effects on different body organs, its presentation and complications: i. Skin lesions ii. Subcutaneous fat iii. Arthritis iv. Nails v. Liver vi. Vasculature

Results iii. Potential utility of FDG-PET/CT in defining and quantifying inflammation in: i. Skin lesions ii. Subcutaneous fat iii. Arthritis iv. Nails v. Liver vi. Vasculature

Conclusions iv. Usage of non-attenuation corrected vs. attenuation corrected PET images in assessing skin lesions and extremities of psoriatic patients i. Photon attenuation related to skin and extremities during PET scan ii. Attenuation correction and its effects on skin and joins FDG uptake measurement iii. Importance of non-attenuation corrected images in assessing psoriasis involvement of skin, joints and nail beds. RESEARCH SUPPORT: Please find attachment