Endoscopic third ventriculostomy with choroid plexus cauterization: predictors of long-term success and comparison with shunt placement for primary treatment of infant hydrocephalus
Authors: Warf Benjamin C. , Weber Daniel S. , Day Emily L. , Riordan Coleman P. , Staffa Steven J. , Baird Lissa C. , Fehnel Katie P. , Stone Scellig S. D. 
Published: May 2023

OBJECTIVE
Endoscopic third ventriculostomy (ETV) with choroid plexus cauterization (CPC) can avoid ventriculoperitoneal shunt (VPS) dependence in very young hydrocephalic children, although long-term success as a primary treatment in North America has not been previously reported. Moreover, optimal age at surgery, impact of preoperative ventriculomegaly, and relationship to prior cerebrospinal fluid (CSF) diversion remain poorly defined. The authors compared ETV/CPC and VPS placement for averting reoperation, and they evaluated preoperative predictors for reoperation and shunt placement after ETV/CPC.

METHODS
All patients under 12 months of age who underwent initial hydrocephalus treatment via ETV/CPC or VPS placement at Boston Children’s Hospital between December 2008 and August 2021 were reviewed. Analyses included Cox regression for independent outcome predictors, and both Kaplan-Meier and log-rank rank tests for time-to-event outcomes. Cutoff values for age and preoperative frontal and occipital horn ratio (FOHR) were determined with receiver operating characteristic curve analysis and Youden’s J index.

RESULTS
In total, 348 children (150 females) were included with principal etiologies of posthemorrhagic hydrocephalus (26.7%), myelomeningocele (20.1%), and aqueduct stenosis (17.0%). Of these, 266 (76.4%) underwent ETV/CPC and 82 (23.6%) underwent VPS placement. Treatment choice largely reflected surgeon preferences before practice shifted toward endoscopy, with endoscopy not considered for > 70% of initial VPS cases. ETV/CPC patients trended toward fewer reoperations, and Kaplan-Meier analysis estimated that 59% of patients would achieve long-term shunt freedom through 11 years (median 42 months of actual follow-up). Among all patients, corrected age < 2.5 months (p < 0.001), prior temporizing CSF diversion (p = 0.003), and excess intraoperative bleeding (p < 0.001) independently predicted reoperation. Among ETV/CPC patients, corrected age < 2.5 months (p = 0.031), prior CSF diversion (p = 0.001), preoperative FOHR > 0.613 (p = 0.011), and excessive intraoperative bleeding (p = 0.001) independently predicted ultimate conversion to VPS. The actual VPS insertion rates remained low in patients who were ≥ 2.5 months old at ETV/CPC either with prior CSF diversion (2/10 [20.0%]) or without prior CSF diversion (24/123 [19.5%]); however, the actual VPS insertion rates increased in patients who were < 2.5 months old at ETV/CPC with prior CSF diversion (19/26 [73.1%]) or without prior CSF diversion (44/107 [41.1%]).

CONCLUSIONS
ETV/CPC successfully treated hydrocephalus in most patients younger than 1 year irrespective of etiology, averting observed shunt dependence in 80% of patients ≥ 2.5 months of age regardless of prior CSF diversion and in 59% of those < 2.5 months of age without prior CSF diversion. For infants aged < 2.5 months with prior CSF diversion, particularly those with severe ventriculomegaly, ETV/CPC was unlikely to succeed unless safely delayed.