EVALUATION OF DIRECT RADIOGRAPHIC MAGNIFI CATION (DIMA) IN THE EARLY DETECTION OF INFLAMMATORY RHEUMATIC LESIONS - COMPARISON WITH THE HIGH-RESOLUTION CONVENTIONAL TECHNIQUE

Rheumatological joint disorders were examined with mammographic film-s creen combinations and high-definition microfocal magnification radiog raphy. Our objective was to evaluate the potentials of magnification r adiography in diagnosing arthritis by means of interobserver and ROC a nalysis. The microfocal X-ray unit had a spot size of 20-130 mum; 5-fo ld magnification was performed. Digital luminescence radiography was e mployed; digital image processing included simulation of conventional technique and edge enhancement. Eighty radiographs were obtained with conventional and magnification technique. All films were analyzed by f ive readers. Anatomical and pathological structures were evaluated. Th e percentage of uncertain findings in magnification radiography was lo wer compared to conventional radiographs (14 % to 26 %); in 8 % (compa red to 19 %) the diagnosis of erosions was uncertain. Additionally ROC analysis was carried out. Magnification radiography was significantly (p < 0.03) better than the conventional films.