Brydon H L, Bayston R, Hayward R, Harkness W
Department of Neurosurgery, Great Ormond Street Hospital for Children, London, UK.
Br J Neurosurg. 1996 Jun;10(3):245-51. doi: 10.1080/02688699650040098.
Most removed shunt valves are discarded with no investigation into why they had to be replaced or whether they still performed to specification. However, improvements in valve design will only occur if valves that have needed removal are examined and the reasons that they failed are determined. An in-depth study of 43 valves that were removed in this unit over a 15-month period was performed. They were submitted to a four-part study, comprising flow-pressure testing, opening and closing pressure measurement, assessment of the susceptibility to syphoning, and dismantling with internal inspection of the valve components. Overall, 81% of valves failed to meet the manufacturers' specified performance data, even though the peroperative cause of shunt failure was thought to lie outside the valve. Over 80% of valves with metallic parts were found to have accumulated debris internally, and this was thought to have impaired their performance. In contrast, only 25% of non-metallic valves contained debris, a significant difference (0.01 > p > 0.001). All of the valves had a high tendency to overdrainage. Attention is drawn to the high number of malfunctioning valves. It is recommended that a change of valve should be considered in all shunt revisions, and that future valve designs should avoid metal components.
大多数被移除的分流阀都被丢弃了，没有对其为何必须更换或是否仍符合规格进行调查。然而，只有在检查那些需要移除的阀门并确定其失效原因后，阀门设计才能得到改进。对本单位在15个月内移除的43个阀门进行了深入研究。这些阀门接受了四个部分的研究，包括流量-压力测试、开闭压力测量、虹吸敏感性评估以及拆解并对阀门部件进行内部检查。总体而言，81%的阀门未能达到制造商规定的性能数据，尽管分流失败的手术原因被认为不在阀门。超过80%带有金属部件的阀门内部有杂物堆积，这被认为影响了它们的性能。相比之下，只有25%的非金属阀门有杂物，差异显著（0.01 > p > 0.001）。所有阀门都有很高的过度引流倾向。要注意有大量阀门出现故障。建议在所有分流修正手术中都考虑更换阀门，并且未来的阀门设计应避免使用金属部件。
