Spinal cysticercosis is a rare form of neurocysticercosis with an incidence of 0.7 to 5.85%.[4
] This low incidence of spinal cysticercosis can be explained on the basis of ‘sieve effect’. Majority of cysticerci cannot pass through the subarachnoid space at the cervical level due to its size and the physiological sieve.[1
Spinal neurocysticercosis occurs in patients with intracranial neurocysticercosis in approximately 75% of the cases, and isolated cases of spinal neurocysticercosis either intra medullary or extramedullary are considered to be very rare.[5
] Spinal forms have been identified in the vertebral, extradural, intradural, and intramedullary regions. Intramedullary involvement in cysticercosis is seldom observed accounting for fewer than 20% of the intradural spinal cases.[1
] Migration of the cysticercus through the ventriculo-ependymal pathway and hematogenous dissemination has been identified to be the possible pathogenetic mechanisms. The higher incidence of spinal neurocysticercosis in the thoracic region may be related to the high blood flow in the thoracic segment of the spinal cord.[4
These patients usually present with radicular pain, paraesthesia, paraparesis, bowel and bladder incontinence, and sensory loss.[1
] The clinical presentation depends on location, spinal level, lesion size and presence or absence of inflammation.[5
] Our patient presented with features of cord compression.
In the absence of previous history of neurocysticercosis or subcutaneous nodules, it may be difficult to clinically suspect intramedullary cysticercosis.[7
] High eosinophilic count and calcification of soft tissues in the plain radiogram may be suggestive, but such are rare.[4
] Cerebrospinal fluid and serum enzyme linked immunoelectric transfer blot assay for cysticercus antibody may be helpful.[7
] Cerebrospinal fluid studies were not performed in this case, as the diagnosis was not considered preoperatively. MR imaging can help in diagnosis of these lesions on which the cysticercal cysts appear hypointense on T1W1 MRI and hyperintense on T2W1 with surrounding edema.[6
] Sometimes, MRI features may be similar to intramedullary or extramedullary neoplastic mass lesions, as in our case.
Though various therapeutic options exist for spinal neurocysticercosis, the rarity of spinal involvement has precluded the evolvement of definite guidelines as compared to cerebral neurocysticercosis.[5
] Medical treatment of intramedullary spinal cysticercosis can be considered in patients with a stable neurological status and in cases diagnosed by cerebrospinal fluid assay. However, in patients presenting with acute or progressive neurological state, and in those where the diagnosis is missed or is in doubt, surgical excision is the choice of treatment as histopathology not only confirms the diagnosis, but early surgery also provides recovery before any irreversible cord damage takes place.[8
] Postoperatively, anticysticercal drugs should be instituted.[4