Clinical evaluation of shunt implantations using Sophy programmable pressure valves: comparison with Codman-Hakim programmable valves.

We describe our experience with Sophy programmable valve shunts, compared with Codman-Hakim programmable shunts in cases with normal pressure hydrocephalus (NPH) after subarachnoid hemorrhage (SAH). A total of 147 consecutive patients underwent 204 shunt implantations (102 Sophy valves, 51 Codman-Hakim valves, 51 nonprogrammable valves). Of these, 23 Sophy and 25 Codman-Hakim valves respectively were implanted into patients with NPH after SAH. Comparison of reprogramming rate and frequency in cases with NPH after SAH between Sophy and Codman-Hakim valves revealed similar reprogramming rates (65.2 vs. 64.0%) but a higher frequency with the former (1.70 vs. 1.08 times/person). The mean difference between initial and final pressure was 65.3+/-45.8mmH(2)O in cases with Sophy valves, and 25.0+/-14.1mmH(2)O with Codman-Hakim valves. The average period which was required to determine the final pressures with Sophy and Codman-Hakim valves were 56.5+/-45.0 days and 43.3+/-45.7 days, respectively. Total incidence of complications of Sophy and Codman-Hakim valve shunt systems in cases with NPH after SAH were 26.1% (6/23) and 16% (4/25), respectively. Total instances requiring shunt revision with Sophy valves in cases of NPH after SAH were 6 of 23 (26.1%), while for Codman-Hakim valves the figure was 2 of 25 (8.0%). Sophy, as well as Codman-Hakim programmable valve shunts, allow alteration of opening pressure after the implantation according to patients' conditions, which may contribute to reduction of revision. Similar reprogramming rates but lower frequency, and smaller difference between initial and final pressure in Codman-Hakim valves may be ascribed to finer pressure ranges and ease of reprogramming, which facilitates earlier reprogramming and decisions regarding final optimal opening pressure.