The standard of care for treatment of glioblastoma results in a mean survival of only 12 to 15 months. Convection-enhanced delivery (CED) is an investigational therapy to treat glioblastoma that utilizes locoregional drug delivery via a small-caliber catheter placed into the brain parenchyma. Clinical trials have failed to reach their endpoints due to an inability of standard catheters to fully saturate the entire brain tumor and its margins. In this study, we examine the effects of controlled catheter movement on dye dispersal volume in agarose gel brain tissue phantoms. Four different catheter movement control protocols (stationary, continuous retraction, continuous insertion, and intermittent insertion) were applied for a single-port stepped catheter capable of intrainfusion movement. Infusions of indigo carmine dye into agarose gel brain tissue phantoms were conducted during the controlled catheter movement. The dispersal volume (V_d), forward dispersal volume (V_df), infusion radius, backflow distance, and forward flow distance were quantified for each catheter movement protocol using optical images recorded throughout the experiment. V_d and V_df for the retraction and intermittent insertion groups were significantly higher than the stationary group. The stationary group had a small but significantly larger infusion radius than either the retracting or the intermittent insertion groups. The stationary group had a greater backflow distance and lower forward flow distance than either the retraction or the intermittent insertion groups. Continuous retraction of catheters during CED treatments can result in larger V_d than traditional stationary catheters, which may be useful for improving the outcomes of CED treatment of glioblastoma. However, catheter design will be crucial in preventing backflow of infusate up the needle tract, which could significantly alter both the V_d and shape of the infusion.

中文翻译：

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受控的导管运动影响琼脂糖凝胶脑部幻影中的染料分散体积。

治疗胶质母细胞瘤的护理标准导致平均生存期仅为12至15个月。对流增强递送（CED）是一种治疗胶质母细胞瘤的研究性疗法，它利用通过放置在脑实质中的小口径导管进行局部药物递送。由于标准导管无法完全浸润整个脑瘤及其边缘，因此临床试验未能达到其终点。在这项研究中，我们检查了受控的导管移动对琼脂糖凝胶脑组织体模中染料分散体积的影响。四种不同的导管运动控制方案（固定，连续缩回，连续插入和间歇插入）应用于能够进行输注运动的单口阶梯式导管。在受控的导管移动过程中，将靛蓝胭脂红染料注入琼脂糖凝胶脑组织体模中。分散体积（V _d），前向分散的体积（V _DF），输液半径，逆流距离，和向前流动距离为利用记录在整个实验光学图像中的每个导管运动协议进行定量。缩回和间歇插入组的V _d和V _df显着高于固定组。固定组的输注半径比缩回或间歇插入组小但明显更大。固定组比缩回组或间歇插入组具有更大的回流距离和更低的向前流动距离。在CED治疗期间持续回缩导管可导致更大的与传统的固定导管相比，V _d可能对改善CED治疗胶质母细胞瘤的疗效有用。但是，导管设计对于防止输注液沿针道回流至关重要，这可能会显着改变V _d和输注形状。