A valve for use in a shunt system to drain fluid from one part of a patient's body to another is provided. In an exemplary embodiment, the valve is operable at a threshold pressure that is selectively adjustable up to at least about 400 mm H2O at increments in the range of about 10 mm H2O to 40 mm H2O. The ability of the valve to operate at a high threshold pressure and to be adjusted at relatively small increments renders the valve particularly advantageous for use in younger hydrocephalus patients. In particular, the operating pressure of the valve can be gradually limited in small increments over a period of time to slowly force the patient's own resorption system to circulate cerebrospinal fluid. At high operating pressures of at least about 400 mm H2O shunt independence can be achieved thereby allowing the shunt to be successfully removed.