New MRI grading system for the diagnosis and management of mycetoma.

The management of patients with mycetoma depends on accurate identification of the causative organisms and of the extent of disease involvement along the different tissue planes. Disease involvement cannot accurately be assessed with the available diagnostic tools, so in this study we set out to evaluate the effectiveness of MRI in the diagnosis and management of mycetoma. Forty-two patients with confirmed mycetoma had MRI examination of the affected parts. A grading system, The Mycetoma Skin, Muscle, Bone Grading System (MSMBS), was used to describe and grade disease severity on the basis of MRI findings. The logistic regression test was used to correlate the clinical and MRI findings. The study showed that MRI can help in the diagnosis and management of mycetoma patients. The dot-in-circle sign, conglomerated foci with low signal intensity and macro- and micro-abscesses on a background of a hypointense matrix are all diagnostic of mycetoma. In patients with mycetoma, the MSMBS can grade disease severity, compare patients and help to manage them. Further studies are needed to determine to what extent the grading system can be used to determine a patient's prognosis.