In 3 patients with epidural abscess, 2 in the cervical spine and 1 in the lumbar spine the definite diagnosis was established by magnetic resonance imaging (MR). In 1 patient computerized tomography was performed but the correct diagnosis was revealed only by MR. The infections were all acute and due to Staphylococcus aureus organisms. One patient developed a tetraparesis on the third day, before the diagnosis was established or antibiotic treatment initiated. The other 2 showed only minor and passing neurologic deficits. None was subjected to laminectomy. In 2 cases the diagnosis was confirmed by puncture. None of the patients had a preceding trauma or a known focus for the staphylococcal infection.