Intraventricular Neurocysticercosis: Comparative Analysis of Different Localizations. Clinical Course and Treatment. A Systematic Review.

Background:  Neurocysticercosis (NCC) is significant due to its high prevalence and considerable morbidity and mortality. Intraventricular NCC (IVNCC) is less common than parenchymal NCC. It may have a rapidly progressive course and it requires a corresponding therapeutic response. Despite the extensive literature dealing with NCC and intraventricular cystic lesions, there are no systematic reviews on the clinical course and treatment of the infestation. Our main objective was to analyze the clinical type of the disease and the management of each ventricle separately based on case reports or series with individual data on the course and treatment of the disease. We used the data on the signs and symptoms and treatment of patients from published series on IVNCC.

Method:  We performed a search in the Medline database. Google Scholar was also randomly searched. We extracted the following data from the eligible studies: age and gender, symptoms, clinical signs, diagnostic examinations and findings, localization, treatment, follow-up period, outcome, and publication year. In this study, all the data are presented in the form of absolute and relative numbers. The frequency of signs and symptoms, treatment, and outcomes of the observed groups were assessed using the chi-squared test and the Fisher exact test. A p value of <0.05 was considered statistically significant.

Results:  We selected 160 cases of IVNCC and divided them according to their localization into five categories. Hydrocephalus was observed in 134 cases (83.4%). Patients with isolated IVNCC were younger (p = 0.0264) and had a higher percentage of vesicular cysts (p < 0.00001). In mixed IVNCC, degenerative and multiple confluent cysts predominate (p = 0.00068). Individuals with fourth- and third-ventricular cysts (potentially an obstructive form) are younger than those with lateral ventricular cysts (potentially a less obstructive form; p = 0.0083). The majority of patients had individual symptoms for a longer period before acute onset of the disease (p < 0.00001). The predominant clinical manifestation was headache (88.7%); the proportion within the groups ranged from 100 to 75% without statistical significance (p = 0.074214). The same was true for patients with symptoms of vomiting or nausea, who had a lower and roughly balanced percentage of 67.7 to 44.4% (p = 0.34702). Altered level of consciousness (range: 21-60%) and focal neurologic deficit (range: 51.2-15%) are the only clinical categories with a statistical significance (p < 0.001 and 0.023948). Other signs and symptoms were less frequent and statistically irrelevant. Surgical resection of the cyst including the parasite was the of treatment of choice, varying from 55.5 to 87.5% (p = 0.02395); endoscopy (48.2%) and craniotomy (24.4%), each individually, showed statistical significance (p = 0.00001 and 0.000073, respectively). The difference was also relevant among patients in whom cerebrospinal fluid (CSF) diversion was performed with/without medical treatment (p = 0.002312). Postoperatively, 31.8% of patients received anthelmintics with/without anti-inflammatory or other drugs. Endoscopy, open surgery, and postoperative antiparasitic therapy showed statistically significant differences (p < 0.001). Favorable outcomes or regression of symptoms were recorded in 83.7%, and mortality was recorded in 7.5% cases. In the case series, the clinical signs and symptoms were the following: headache (64%), nausea and vomiting (48.4%), focal neurologic deficit (33.6%), and altered level of consciousness (25%). Open surgery was the predominant form of intervention (craniotomy in 57.6% or endoscopy in 31.8%, with a statistical significance between them; p < 0.00001).

Conclusion:  IVNCC is an alarming clinical condition. Hydrocephalus is the dominant diagnostic sign. Patients with isolated IVNCC were recognized at a younger age than those with mixed IVNCC; patients with cysts in the fourth and third ventricles (as a potentially more occlusive type of disease) presented their symptoms at a younger age than those with lateral ventricular NCC. The majority of patients had long-term signs and symptoms before acute onset of the disease. Headache, nausea, and vomiting were the most common symptoms of infestation accompanied by altered sensorium and focal neurologic deficits. Surgery is the best treatment option. A sudden increase in intracranial pressure due to CSF obstruction with successive brain herniation is the leading cause of fatal outcomes.