Intrathecal gadodiamide for identifying subarachnoid and ventricular neurocysticercosis.

OBJECTIVE Some neurocysticercosis cysts may remain hidden despite novel MRI sequences. This study evaluates the diagnostic value of gadodiamide (GDD)-contrasted MRI cisternography in selected cases of neurocysticercosis. METHODS We included patients aged 18-65 years with a probable diagnosis of subarachnoid cysticercosis in whom previous neuroimaging studies failed to demonstrate the presence of cysts. One millilitre of GDD was administered intrathecally as a contrast agent with subsequent performance of MRI. RESULTS Fourteen patients were included. Optimal contrast diffusion was achieved in nine patients, and partial diffusion was achieved in 4. Intracranial vesicles were identified in 10 patients, with the presence of more than 60 basal subarachnoid vesicles being revealed in all, with five cysts in the fourth ventricle in four patients and a floating cyst in the lateral ventricle in one. In one case, intrathecal GDD demonstrated spinal cysticercosis. No adverse events were reported after intrathecal GDD administration. CONCLUSIONS Intrathecal GDD administration is useful for the diagnosis of subarachnoid and intraventricular neurocysticercosis and can be used to improve diagnostic accuracy in selected cases.