Intramedullary cysticercosis of the spinal cord: a review of patients evaluated with MRI.

OBJECTIVE: Review of cases of intramedullary spinal cord cysticercosis diagnosed with MRI to outline the features and outcome of this overlooked form of presentation of neurocysticercosis.
METHODS: MEDLINE, LILACS, and manual search of case reports or case series of patients with intramedullary cysticercosis evaluated with MRI. Abstracted data included: demographic profile, clinical manifestations, neuroimaging findings, therapy, and follow-up.
RESULTS: Forty-three patients were reviewed. Mean age was 36 years, and 65% were men. Most patients (67%) had parasites located at the thoracic spinal cord. All but two patients had a single cyst. The most common form of presentation was a subacute or chronic transverse myelopathy. On MRI, all lesions had signal properties paralleling that of CSF, and most were surrounded by edema and had a "ring-like" pattern of abnormal enhancement. The scolex of the parasite was visualized in 16 (37%) cases. Twenty-nine patients underwent surgical resection of the lesion, and 14 were medically-treated. Follow-up data was available in 20 surgically-treated and 13 medically-treated patients. Twelve (60%) of the 20 surgically-treated patients recovered completely, and the remaining were left with sequelae or did not improve. In contrast, all the 13 medically-treated patients recovered completely after the use of cysticidal drugs plus corticosteroids (11 cases) or corticosteroids alone (two cases).
CONCLUSIONS: Intramedullary cysticercosis is rare. Clinical and neuroimaging findings may resemble those of other intramedullary lesions, but the visualization of the scolex or the incidental discovery of intracranial lesions provide helpful diagnostic clues. Prognosis is benign provided the correct diagnosis is suspected and patients receive prompt therapy.