MRI OF SCAPHOID PSEUDO-ARTHROSIS USING GD -DTPA - STAGING AND CLINICAL CORRELATION

During a period of two years, 134 patients with pseudo-arthrosis of th e scaphoid were examined by conventional radiography and by MRI in the course of a prospective study. The aim of the study was to define rad iological staging using contrast enhanced MRI in order to improve the prognostic criteria. AU MRI examinations were carried out with a 1.5 T esla scanner (SP63) using a surface coil and T-1 weighted spin echo se quences in sagittal and frontal projection and frontal FLASH T-2 seque nces and axial spin echo T-2 sequences. The T-1 weighted SE sequences in frontal projection were carried out before and after iv contrast (O .1 mmol Gd-DTPA/kg KG). AU sequences were compared with conventional r adiographs and the operative findings. Eight patients in stage 0 showe d high signal intensity of both fragments in T-1 weighted SE sequences and at surgery there was good vascularisation. In 22 cases there was reduced signal intensity in at least one fragment (stage I). 45 patien ts with scaphoid pseudo-arthrosis showed complete signal loss but mark ed contrast uptake with still vital nuclei at surgery (stage II). In 2 2 patients, there was no increase in signal intensity after contrast a nd complete loss of vitality of the fragments at surgery. Staging was not possible in 37 patients because of previous operative intervention . The use of contrast enhanced MRI provides additional information com pared with conventional radiography or plain MRI.