Diagnostik und Verlaufskontrolle von Muskelverletzungen mittels nativer und kontrastmittelunterstützter MRT - experimentelle und klinische Untersuchungen

PURPOSE: To clarify the value of plain and contrast-enhanced MRI for the diagnosis and follow-up of muscle injuries, by means of experimental and clinical studies. METHOD: 24 Wistar rats were studied following standardized division of the calf muscles by means of MRI carried out on the first day, and also after one, two, three and four weeks. In addition, 16 patients with muscle injuries were examined (32 examinations), first between the first and fifth day of trauma, and subsequently over a period of two to seven weeks (average: four weeks). RESULTS: In the animal experiments, there was signal reduction of T1 and an increase of the T2-weighted signal during the acute inflammatory phase. During the subacute reparative phase, there was an increase of both the T1-weighted and T2-weighted signals. These became reduced during the chronic healing phase. Early differentiation between intramuscular haematomas and bleeding, surrounding oedema and recognition of the divided muscle fibres was possible only after the intravenous injection of an MR contrast medium (Gd-DTPA). Suture of the divided muscles resulted in more rapid healing without major defects. CONCLUSION: It is possible to follow up the healing process after muscle injuries by means of plain MR. Contrast-enhanced MR allows early evaluation of muscle abnormalities, and is particularly valuable for recognising the margins of the injured muscles.