We present computerized tomography (CT) and magnetic resonance imaging (MRI
) findings of a costal hydatid cyst (Echinococcus multilocularis) causing s
pinal cord compression. The hydatid disease was proved histologically. MRI
was not only very useful for determining the spinal extension of the diseas
e by its multiplanar imaging capability, but also gave important informatio
n about the texture of the cyst, thus aiding the preoperative diagnosis. (C
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