Computational and experimental study of proximal flow in ventricular catheters - Technical note
Computational and experimental study of proximal flow in ventricular catheters - Technical note
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DOI：
10.3171/jns.2003.99.2.0426
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发表时间：
2003-08-01
影响因子：
4.1
通讯作者：
Sanford, RA
中科院分区：
文献类型：
--
作者：
Lin, J;Morris, M;Sanford, RA
脑积水的分流插入治疗充满了高失败率。有证据表明，导管中的近端孔是堵塞的主要部位。作者通过使用计算流体动力学（CFD）、二维地下水位实验和三维（3D）自动测试装置以及实际导管研究了脑室导管设计。使用CID模型，作者计算出总流体质量的58%流入导管的最近端孔，并且超过80%流入八孔导管内的两组最近端孔。事实上，导管上的大多数孔都是无效的。使用两种完全不同的方法对这些发现进行了实验验证：分流导管的地下水位模型和具有实际导管的3D自动化测试装置，以借助墨水可视化流型。由于大部分流量进入导管的最近端孔，因此堵塞通常发生在该位置，并且与远端孔处的堵塞不同，近端孔的堵塞导致导管完全失效。鉴于这一发现，采用两种模型构思并测试了包含不同孔型分布和脑室导管尺寸的新设计。几何特征的这些变化显著地改变了进入的质量流率分布。总之，近端脑室导管中的新设计（沿导管头端沿着具有可变孔径）允许液体沿导管长度更均匀地沿着进入导管，从而降低了其堵塞的可能性。
The treatment of hydrocephalus with shunt insertion is fraught with high failure rates. Evidence indicates that the proximal holes in a catheter are the primary sites of blockage. The authors have studied ventricular catheter designs by using computational fluid dynamics (CFD), two-dimensional water table experiments, and a three-dimensional (3D) automated testing apparatus together with an actual catheter. With the CID model, the authors calculated that 58% of the total fluid mass flows into the catheter's most proximal holes and that greater than 80% flows into the two most proximal sets of holes within an eight-hole catheter. In fact, most of the holes in the catheters were ineffective. These findings were experimentally verified using two completely different methodologies: a water table model of a shunt catheter and a 3D automated testing apparatus with an actual catheter to visualize flow patterns with the aid of ink. Because the majority of flow enters the catheter's most proximal holes, blockages typically occur at this position, and unlike blockages at distal holes, occlusion of proximal holes results in complete catheter failure. Given this finding, new designs that incorporated varying hole pattern distributions and size dimensions of the ventricular catheter were conceived and tested using two models. These changes in the geometrical features significantly changed the entering mass flow rate distribution. In conclusion, new designs in proximal ventricular catheters with variable hole diameters along the catheter tip allowed fluid to enter the catheter more uniformly along its length, thereby reducing the probability of its becoming occluded.