RESUMO
PURPOSE: Amyloid shoulder arthropathy is a frequent finding in long-term hemodialysis patients. Assessing the symptoms is fundamental in the approach to these patients but their long life expectancy means that the correct imaging quantification of scapulohumeral joint impairment is just as important. We investigated the role of MRI in amyloid shoulder arthropathy in long-term hemodialysis patients. MATERIAL AND METHODS: From January, 1995, to December, 1996, twelve long-term (mean: 13 years) hemodialysis patients with amyloid shoulder arthropathy were examined with MRI. All of them had undergone physical examination to detect the most involved scapulohumeral joint. MRI was carried out with a 1.0 T Magnetom Impact unit (Siemens, Germany) using T1-weighted Turbo SE sequences at high resolution on coronal and sagittal planes, respectively parallel and perpendicular to the supraspinatus tendon, and FLASH sequences on the axial plane. Six patients were then submitted to surgery. RESULTS: MRI had identified 3/12 rotator cuff tears (always involving the supraspinatus tendon and other tendons), 7/12 rotator cuff tears from supraspinatus tendon injury, and 1/12 thickening and structural dishomogeneity of the supraspinatus tendon. Finally, no structural changes were shown in 1/12 cases. In addition, most MR examinations (11/12) showed some inhomogeneous material characterized by intermediate-to-low signal intensity on T1-weighted sequences; such changes were found in subacromial and subdeltoid bursas in part of the articular capsule and were always associated with hypointense nodular images in all sequences. Surgery was carried out in 6 patients and confirmed both the structural changes of the rotator cuff and the presence of amorphous material which appeared to be amyloid deposits at subsequent histology. MRI proved to be a very reliable tool even in the study of skeletal structural changes, permitting both the identification of periarticular calcifications and the accurate analysis and quantification of subchondral erosions. CONCLUSIONS: MRI was a very reliable tool not only in the study of rotator cuff tears due to amyloid deposition but also in the analysis of bone changes. Thus MRI could play a growing role in treatment planning.