Evaluering av skulderens rotatormuskulatur med magnettomografi.

Rotator cuff tears are difficult to diagnose clinically, both in the acute and the chronic phase. Both conservative and surgical treatment give the best results if the injury is detected early. Magnetic resonance imaging (MRI) has recently been introduced for diagnoses of cuff tears. The purpose of this study was to establish the accuracy of MRI in relation to surgical findings in the same patient group. MRI was used in the diagnosis of 25 patients who later underwent surgery for injury to the rotator cuff. During the surgery, 19 total tears were identified, of which 15 had been described by MRI. MRI showed a sensitivity of 79% and a specificity of 83%. The predictive value of a positive test was 83%. In experienced hands, MRI is extremely accurate for detecting rotator cuff injuries, but ultrasonography should still be the first method of diagnosis in Norway, because of its accuracy when used by experienced practitioners, and its availability and low cost.