“…In communicating (non-obstructive) hydrocephalus, the four interconnected cavities, or ventricles, expand with increasing fluid pressure, and secondary cerebral abnormalities ensue (McAllister, 2012). Congenital or infantile onset hydrocephalus is highly heterogeneous in etiology, with a prevalence of 1 in 1,000 births (Jeng, Gupta, Wrensch, Zhao, & Wu, 2011; Tully et al, 2016). Genetic etiologies of congenital hydrocephalus are rarely identified and include mutations in L1CAM , AP1S2 , and POMT1 (Tully & Dobyns, 2014).…”