Objective: Pediatric patients with long-term shunts may experience specific complications related to the segregation of the supra- and infratentorial spaces along with different pressure regimens, leading to either mesencephalic syndromes during shunt dysfunction or isolated fourth ventricle (IFV). An accepted treatment to reestablish normal CSF pathways and reequilibrate the transtentorial pressures is endoscopic aqueductal stenting (EAS) to avoid restenosis. In the present paper, the authors studied children treated with EAS during the last decade for both IFV and obstructive hydrocephalus, evaluated its impact on the course of the disease, and identified prognostic factors for EAS success.
Methods: A noninterventional retrospective study of routinely acquired data was performed, including all hydrocephalic children undergoing EAS between 2011 and 2019 at Hôpital Necker, Paris, France. The following variables were analyzed: etiology of hydrocephalus; number of surgeries before and after stent placement; indication for EAS; type of stent connection (i.e., connected or not to a ventriculoperitoneal shunt); and the stent position. Stent failure was defined as the need to perform further shunt revision. Univariate and multivariate analyses were run to identify factors associated with stent failure.
Results: Seventeen patients with a mean age at stent placement of 6 years (SD 6.5 years, range 1 month-18 years) and with a mean follow-up after EAS of 47.5 months (SD 33.7 months, range 5-120 months) were included in the analysis. The etiology of hydrocephalus was as follows: obstructive tumoral (41%), posthemorrhagic (35%), postinfectious (12%), and dysraphism related (12%). The indication for EAS was IFV (47%), rostral midbrain dysfunction syndrome (35%), prevention of secondary aqueductal stenosis after debulking surgery (12%), or primary aqueductal stenosis (6%). No transient or permanent neurological deficits related to the procedure were observed. After EAS, 10 patients did not require further surgeries (59%), and for the others the number of hydrocephalus-related surgeries significantly decreased after stenting. In univariate analysis posthemorrhagic etiology and prevention of aqueductal stenosis were identified as predictors of a good outcome, whereas in multivariate analysis posthemorrhagic hydrocephalus was found to predict a favorable outcome.
Conclusions: The results confirm EAS as a first-line treatment for IFV and suggest its efficacy in changing the history of hydrocephalic patients who have undergone multiple operations and who experience rostral midbrain dysfunction syndrome, as well as efficacy in the prevention of aqueductal stenosis in selected cases of obstructive tumoral hydrocephalus.
Keywords: endoscopic aqueductal stenting; hydrocephalus; isolated fourth ventricle; mesencephalic syndrome; neuroendoscopy; ventriculoperitoneal shunt; ventriculostomy.