 If CSF removal is still required at 44 weeks EGA and there is consensus among the treating neonatologist and neurosurgeon, permanent VP shunts will be surgically implanted. The rate of VP shunts required by 44 weeks EGA and by 12 months corrected age will be monitored. Formal neurodevelopmental evaluations will be performed by a blinded developmental psychologist at 18-24 months corrected age to assess neurocognitive and psychomotor function in low- versus standard-threshold groups. Each infant will be scored using the Bayley Scales of Infant Development. 