Treatment strategies for hydrocephalus related to Dandy-Walker syndrome: Evaluating procedure selection and success within the Hydrocephalus Clinical Research Network

Objective: Treating Dandy-Walker syndrome-related hydrocephalus (DWSH) involves either a CSF shunt-based or endoscopic third ventriculostomy (ETV)-based procedure. However, comparative investigations are lacking. This study aimed to compare shunt-based and ETV-based treatment strategies utilizing archival data from the Hydrocephalus Clinical Research Network (HCRN) registry. Methods: A retrospective review of prospectively collected and maintained data on children with DWSH, available from the HCRN registry (14 sites, 2008-2018), was performed. The primary outcome was revision-free survival of the initial surgical intervention. The primary exposure was either shunt-based (i.e., cystoperitoneal shunt [CPS], ventriculoperitoneal shunt [VPS], and/or dual-compartment) or ETV-based (i.e., ETV alone or with choroid plexus cauterization [CPC]) initial surgical treatment. Primary analysis included multivariable Cox proportional hazards models. Results: Of 8400 HCRN patients, 151 (1.8%) had DWSH. Among these, the 102 patients who underwent shunt placement (79 VPSs, 16 CPSs, 3 other, and 4 multiple proximal catheter) were younger (6.6 vs 18.8 months, p < 0.001) and more frequently had 1 or more comorbidities (37.3% vs 14.3%, p = 0.005) than the 49 ETV-treated children (28 ETVCPC). Fifty percent of the shunt-based and 51% of the ETV-based treatments failed. Notably, 100% (4/4) of the dualcompartment shunts failed. Adjusting for age, baseline ventricular size, and comorbidities, ETV-based treatment was not significantly associated with earlier failure compared with shunt-based treatment (HR for failure 1.32, 95% CI 0.77-2.26; p = 0.321). Complication rates were low: 4.9% and 6.1% (p = 0.715) for shunt- and ETV-based procedures, respectively. There was no difference in survival between ETV-CPC- and ETV-based treatment when adjusting for age (HR for failure 0.86, 95% CI 0.29-2.55, p = 0.783). Conclusions: In this North American, multicenter, prospective database review, shunt-based and ETV-based primary treatment strategies of DWSH appear similarly durable. Pediatric neurosurgeons can reasonably consider ETV-based initial treatment given the similar durability and the low complication rate. However, given the observational nature of this study, the treating surgeon might need to consider subgroups that were too small for a separate analysis. Very young children with comorbidities were more commonly treated with shunts, and older children with fewer comorbidities were offered ETV-based treatment. Future studies may determine preoperative characteristics associated with ETV treatment success in this population.