Value of Tomosynthesis for the Detection of Sacro-iliitis (TOMOS SI)

Consecutive patients referred to CT for exploration of sacrollitis will be included and investigated with standard radiography, CT and tomosynthesis of SI joints. Imaging examinations will be performed at day of enrollment as follow : X-ray and CT as standard management and tomosynthesis as additional evaluation. CT will be considered as the reference standard Sacroiliitis will be assessed in a centralized, blind and randomized retrospective reading of all imaging modalities by two independent radiologists. Diagnostic performances and radiation doses of tomosynthesis will be compared to those of standard CT and X-ray examinations.