[Spontaneous spinal subdural hematoma: MRI findings in two cases].

Spontaneous spinal subdural hematoma is an uncommon finding. This report of two cases of spinal subdural hematoma (one hyperacute and one subacute) discusses the current theory of how it develops, the MRI findings, its differentiation from spinal epidural hematoma, and the value of MRI in monitoring patients undergoing conservative treatment. The most significant MRI findings in the hyperacute phase were isointense signal on T1-weighted sequences and hyperintense signal on T2-weighted sequences. Moreover, T2-weighted gradient-echo sequences showed a hypointense peripheral ring. In the subacute phase, a hyperintense signal was seen on T1-, T1-fat-suppression, and T2-weighted sequences.