Artificial shunting of cerebrospinal fluid

A compact three-stage shunt valve system (Orbis Sigma Valve) which operates as a flow regulator within certain differential pressure values has been clinically evaluated in the treatment of hydrocephalus. Clinical trials were performed in 134 cases, covering 128 patients aged from 1 day to 79 years with a mean age at implantation of 11.4 years. One-third of the implants was performed to replace failed DP shunts. Using actuarial statistics, 83.9% of the shunts continued to adequately manage hydrocephalus at three years. Overdrainage occurred in 2 cases (1.5%) and insufficient drainage occurred in four cases (3%). Compared with literature for conventional DP shunts, the incidence of these phenomena is extremely low. Based on the results summarized in this paper and those already reported in the literature, the OSV appears to address the overdrainage limitations of conventional shunts.