The aim was to determine the place of magnetic resonance imaging (MRI) and ultrasonographic (US) examination in the diagnosis and follow-up of Sjögren's syndrome (SS).
Parotid MRI and US examinations were carried out on 44 primary SS patients and 52 controls of similar age.
The most important structural changes in SS were different degrees of parenchymal inhomogeneity, which could be detected by both methods, and were found more frequently in the SS patients than in the controls (MRI: 95.4 vs 17. 3%; US: 88.6 vs 7.7%; P<0.001). There was good agreement between the MRI and US findings both in the SS cases (93.2%) and in the controls (86.5%). In one SS patient who developed parotid lymphoma, the US examination showed a hypoechoic 'cobblestones'-like inhomogeneous internal pattern which was coupled with an almost homogeneous MRI pattern.
MRI appears unnecessary as a routine method in the diagnosis of SS; US examination is suitable both for the diagnosis and follow-up of SS. The above combination of the seemingly contradictory US and MRI findings is highly characteristic of lymphoma which has developed in the course of the disease.