Research Development Of The Predictive Factors And Treatment And Pathogenesis Of Chronic Shunt-dependent Hydrocephalus After Aneurysmal Subarachnoid Hemorrhage

Chronic hydrocephalus requiring cerebrospinal fluid (CSF) shuntsurgery is a common complication after aneurysmal subarachnoidhemorrhage (aSAH). Numerous studies have focused on the predictivefactors, such as age,clinical status on admission,Fisher grade, acutehydrocephalus,intraventricular hemorrhage, location and size of aneurysm,treatment modality and so on. Moreover, some clinical studies wereperformed to explore the possibility of reducing the incidence byfenestration of the lamina terminalis (FLT) or lumbar drainage (LD).There are, however, many controversies about the predictability of thesefactors and the efficiency of FLT and LD. These predicaments may be dueto poor understanding of the precise mechanisms of the development ofchronic shunt-dependent hydrocephalus, which is based on the classicalhypothesis of CSF hydrodynamics. Currently, this classical hypothesisitself has been confronted with some challenges, such as the lymphaticCSF outflow route theory and the ISF-CSF functional unit hypothesis. In this manuscript we review predictors of shunt-dependent hydrocephalusafter aSAH, the efficiency of fenestration of the lamina terminalis andlumbar drainage, and finally we discuss possible pathogenesis underlyingthe development of chronic shunt-dependent hydrocephalus according tothe research development of CSF hydrodynamics.