ASSESSMENT OF THE PERFORMANCE OF CT SCAN VERSUS PLAIN FILMS IN SACROILIITIS DIAGNOSIS

We studied 20 normal subjects and 20 suffering from sacro-iliitis. The performance of the two techniques were compared in studying reports R OC curve from several readers. We assessed the performance of each tec hnique and each sign: CT scan appears as a better technique than plain films. Some signs present a poor interest: osteophytes seen on CT or plain films, subchondral cysts seen on CT. In other respects, articula r cartilage erosions, subchondral sclerosis are main signs as much on CT as on plain films. In conclusion, CT scan allowed an accurate analy sis of sacro-iliitis. It has a better diagnostic value than plain film s and, in case of doubt, should be performed to increase diagnosis sen sibility and specificity.