Introduction: The clinical and MR imaging features of neurosyphilis are highly varied. In this study, we describe the spectrum of the imaging findings in patients with neurosyphilis.

Methods: The MR imaging observations of 35 patients diagnosed to have neurosyphilis on the basis of cerebrospinal fluid reactive for the Venereal Disease Research Laboratory test were reviewed.

Results: All the 35 patients, including four with human immunodeficiency virus coinfection, met the CDC diagnostic criteria for neurosyphilis. Patients were classified into three groups: (1) neuropsychiatric, (2) meningovascular, and (3) myelopathic, based on the dominant clinical manifestations. Fourteen patients with neuropsychiatric manifestations showed diffuse cerebral atrophy (14), parenchymal signal changes in the mesial temporal region (2) and temporal and basifrontal regions (1), infarcts (3), and nonspecific white matter changes (3). Eleven patients with meningovascular form showed infarcts (6), diffuse cerebral atrophy (3), signal changes in the mesial temporal region (3), sulcal exudates (1), progressive multifocal leukoencephalopathy (1), and a mass surrounding the carotid sheath (1). Spine imaging in ten patients with myelopathy showed long-segment signal changes (5), contrast enhancement (2), and dorsal column involvement (2). Three of these patients had normal spinal study. Six patients in the myelopathic group also underwent brain MRI that showed signal changes in the temporal region (2) and frontal region (1), multiple infarcts (1), and enhancing hypothalami (1). Three patients had normal study.

Conclusion: MRI abnormalities in neurosyphilis are protean and mimic of many other neurological disorders and thus require a high index of suspicion to reduce diagnostic omissions.