Dot-in-circle Sign of Mycetoma on Magnetic Resonance Imaging

Mycetoma is a chronic granulomatous disease prevalent in tropical countries, but it also occurs in Europe and the United States.Early diagnosis is important as it has therapeutic implications. Although biopsy and microbiological culture provide the definitivediagnosis, these are difficult to achieve in many instances. The dot-in-circle sign is a recently proposed magnetic resonanceimaging (MRI) sign of mycetoma, which is likely to be highly specific. We present a case of mycetoma of the left calcaneumwith characteristic MRI features.