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Case Reports
. 2011 Oct;21(4):264-6.
doi: 10.4103/0971-3026.90684.

Case report: Dot-in-circle sign - An MRI and USG sign for "Madura foot"

Anitha Sen  1 , Rajesh Subramonia Pillay
Affiliations
Case Reports

Case report: Dot-in-circle sign - An MRI and USG sign for "Madura foot"

Anitha Sen et al. Indian J Radiol Imaging. 2011 Oct.

Abstract

Mycetoma is a chronic granulomatous disease that is more common in tropical than in temperate regions. Early diagnosis is important due to the therapeutic implications. Although biopsy and microbiological culture provide definitive diagnosis, they are time-consuming procedures and may not be able to provide a definite diagnosis in cases of fastidious organisms. The "dot-in-circle" sign has recently been proposed as a highly specific magnetic resonance imaging (MRI) and ultrasonography (USG) sign of mycetoma, which may allow a noninvasive as well as early diagnosis. We present a case of histologically proven mycetoma that demonstrated this sign.

Keywords: Dot-in-circle; magnetic resonance imaging; mycetoma; ultrasonography.

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Conflict of interest statement

Conflict of Interest: None declared.

Figures

Figure 1 (A-D)
Figure 1 (A-D)
Sagittal short-Tau inversion recovery (STIR) MRI image (A) shows osteolytic areas in the tibia (grey arrow) and talus (white arrowhead); “dot-in-circle” lesions (white arrows) are seen in the soft tissue. Sagittal CT scan (B) shows osteolytic areas (black arrowhead) and periosteal reaction (white arrow) in the tibia. Axial T2W MRI image through the sole of the foot (C) and sagittal T2W MRI image (D) show multiple T2-bright round lesions (white arrow) with a central dot (white arrowheads), seen clearly in some lesions and faintly in others
Figure 2
Figure 2
USG image shows hypoechoic lesions with hyperechoic centers (white arrows)
See this image and copyright information in PMC

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