Department of Neurosurgery, Universitätsmedizin Göttingen, Georg-August University Göttingen, 37099, Göttingen, Germany.
Department of Neurosurgery, University Hospital Erlangen, Erlangen, Germany.
Acta Neurochir (Wien). 2020 May;162(5):1033-1040. doi: 10.1007/s00701-020-04228-6. Epub 2020 Jan 30.
Programmable differential pressure (DP) valves combined with an anti-siphon device (ASD) represent the current standard of care in preemtping overdrainage associated with ventriculoperitoneal shunting for hydrocephalus.
We aimed to provide comparative data of four combinations of two ASDs of different working principles in combination with two DP valves in an in vitro model in order to achieve a better understanding of the flow characteristics and potential clinical application.
We analyzed the flow performance of four possible combinations of two DP valves (CHPV [HM]; proGAV 2.0[PG]) in combination with either a gravity-regulated (Shuntassistant [SA]) or a flow-regulated (SiphonGuard [SG]) ASD in an in vitro setup. A DP between 4 and 60 cmHO was generated, and the specific flow characteristics were measured. In addition, the two combinations with gravity-regulated ASDs were measured in defined spatial positions.
Flow characteristics of the SA combinations corresponded to the DP in linear fashion and to the spatial position. Flow characteristics of the SG combinations were dependent upon the DP in a non-linear fashion and independent of the spatial position. Highest mean flow rate of the PG-SG- (HM-SG-) combination was 1.41 ± 0.24 ml/min (1.16 ± 0.06 ml/min). The mean flow rates sharply decreased with increasing inflow pressure and subsequently increased slowly up to 0.82 ± 0.26 ml/min (0.77 ± 0.08 ml/min).
All tested device combinations were able to control hydrostatic effect and prevent consecutive excessive flow, to varying degrees. However, significant differences in flow characteristics can be seen, which might be relevant for their clinical application.
可编程压差（DP）阀与防虹吸装置（ASD）相结合，是目前预防脑积水脑室-腹腔分流术后过度引流的标准治疗方法。
本研究旨在通过体外模型比较两种不同工作原理的 ASD 与两种 DP 阀四种组合的流量特性，为更好地理解其工作特性和临床应用提供参考。
我们分析了两种 DP 阀（CHPV[HM]；proGAV 2.0[PG]）与重力调节型 ASD（Shuntassistant[SA]）或流量调节型 ASD（SiphonGuard[SG]）两种组合在体外模型中的流量性能。在 4 至 60cmH2O 的 DP 下，测量特定的流量特性。此外，还测量了两种具有重力调节型 ASD 的组合在特定空间位置下的流量特性。
SA 组合的流量特性与 DP 呈线性关系，并与空间位置有关。SG 组合的流量特性与 DP 呈非线性关系，与空间位置无关。PG-SG-（HM-SG-）组合的平均流速最高，为 1.41±0.24ml/min（1.16±0.06ml/min）。随着流入压力的增加，平均流速急剧下降，随后缓慢增加至 0.82±0.26ml/min（0.77±0.08ml/min）。
所有测试的设备组合都能够在不同程度上控制流体静力学效应并防止连续过度流动。然而，我们可以看到流量特性存在显著差异，这可能与其临床应用有关。
