Imaging features of neurosyphilis.

Syphilis is an infectious disease caused by the spirochete Treponema pallidum, subspecies pallidum. Although its incidence has declined after the widespread availability of penicillin, it has recently re-emerged, especially in men who have sex with men and in people living with human immunodeficiency virus (HIV). The neurological manifestations of syphilis, generally known as neurosyphilis, may appear at any time during the infection, including the initial years after the primary infection. Neurosyphilis can be asymptomatic, only with cerebrospinal fluid abnormalities, or symptomatic, characterized by several different clinical syndromes, such as meningitis, gumma, meningovascular, brain parenchyma involvement, meningomyelitis, tabes dorsalis, and peripheral nervous system involvement. However, these syndromes may simulate several other diseases, making the diagnosis often a challenge. In addition, syphilis can also be vertically transmitted from mother to child during pregnancy, leading to neurological manifestations. Neuroimaging is essential to demonstrate abnormal brain or spinal cord findings in patients with neurosyphilis, aiding in the diagnosis, treatment, and follow-up of these patients. This article aims to review the imaging features of neurosyphilis, including the early and late stages of the infection.

Primary intramedullary malignant melanoma: can imaging lead to the correct diagnosis?

Melanoma is a malignant neoplasm of melanin-producing cells. Melanoma usually occurs in the skin, but can also arise in any anatomical site that contains melanocytes, such as mucous membranes, the eyes, and the central nervous system (CNS). Primary CNS malignant melanoma most often develops in the leptomeninges. We report a case of a rare intramedullary melanoma of the thoracic spinal cord. A 78-year-old man was treated with surgery, radiotherapy, and immunotherapy for leptomeningeal spread. We also discuss the role of imaging methods in diagnosis and follow-up. Medullary melanoma occurs more frequently in adults. The most common presenting symptoms are the insidious onset of lower extremity weakness and paresthesia. Magnetic resonance imaging is the method of choice for evaluation. Although there are no imaging features to accurately distinguish primary malignant melanoma from other melanocytic or hemorrhagic tumors, hyperintensity on T1-weighted magnetic resonance imaging should lead to inclusion of this neoplasm in differential diagnosis of spinal cord tumors. Positron emission tomography-computed tomography is a useful auxiliary examination to evaluate the extent of local and metastatic disease. Surgical resection is the primary treatment for intramedullary melanoma. However, the efficacy of adjunctive radiotherapy and chemotherapy for primary spinal cord malignant melanoma is still controversial.