Characteristics of ventricular shunt malfunctions among patients with neurocysticercosis

OBJECTIVE: Ventricular shunts used to relieve hydrocephalus among patients with neurocysticercosis have been plagued by high shunt malfunction rates. We examined the characteristics of shunt malfunctions among patients with neurocysticercosis. METHODS: This is a retrospective chart review of data for 122 patients who were admitted with a diagnosis of cysticercosis during a 5.5-year period. Cases of hydrocephalus requiring shunt placement were reviewed with respect to the segment of shunt obstruction, disease activity at the time of shunt placement, and the effects of antihelminthic treatment on shunt failures and longevity. RESULTS: Twenty-one patients required 49 operations for relief of hydrocephalus, including 22 new shunt placements, 23 revisions, and 4 cyst extirpations. Of these shunt failures, 78% occurred within the first 12 months and 96% within 3 years. Of the failures that occurred in the distal segment, 75% occurred within 6 months. By comparison, 33% of proximal segment obstructions and 50% of the total number of valve obstructions occurred within the first 6 months. Of the shunts placed during the vesicular stage of infection, 63% required revisions, compared with 29% of those placed during the colloidal through calcified stages. Nineteen shunts were placed during the vesicular stage, and nine patients received a full course of antihelminthic treatment after shunt placement. In less than 6 months, 33% of the cases involving shunt placement followed by antihelminthic treatment exhibited shunt failure, compared with 90% of the cases without antihelminthic treatment (P < 0.05, X² test). CONCLUSION: Among patients with vesicular stage cysticercosis, placement of a ventriculoperitoneal shunt followed by a course of antihelminthic medication seems to promote shunt longevity.