Department of Radiology, University of Massachusetts, Worcester, Massachusetts 01655, USA.
J Neurointerv Surg. 2013 Jan 1;5(1):69-72. doi: 10.1136/neurintsurg-2011-010170. Epub 2011 Dec 22.
Convection-enhanced delivery (CED) has been shown to be an effective method of administering macromolecular compounds into the brain that are unable to cross the blood-brain barrier. Because the administration is highly localized, accurate cannula placement by minimally invasive surgery is an important requisite. This paper reports on the use of an angiographic c-arm system which enables truly frameless multimodal image guidance during CED surgery.
A microcannula was placed into the striatum of five sheep under real-time fluoroscopic guidance using imaging data previously acquired by cone beam computed tomography (CBCT) and MRI, enabling three-dimensional navigation. After introduction of the cannula, high resolution CBCT was performed and registered with MRI to confirm the position of the cannula tip and to make adjustments as necessary. Adeno-associated viral vector-10, designed to deliver small-hairpin micro RNA (shRNAmir), was mixed with 2.0 mM gadolinium (Gd) and infused at a rate of 3 μl/min for a total of 100 μl. Upon completion, the animals were transferred to an MR scanner to assess the approximate distribution by measuring the volume of spread of Gd.
The cannula was successfully introduced under multimodal image guidance. High resolution CBCT enabled validation of the cannula position and Gd-enhanced MRI after CED confirmed localized administration of the therapy.
A microcannula for CED was introduced into the striatum of five sheep under multimodal image guidance. The non-alloy 300 μm diameter cannula tip was well visualized using CBCT, enabling confirmation of the position of the end of the tip in the area of interest.
已经证明，对流增强输送（CED）是将无法穿过血脑屏障的大分子化合物递送到大脑中的有效方法。由于给药高度定位，因此通过微创手术进行准确的套管放置是一个重要的必要条件。本文报告了使用血管造影 C 臂系统的情况，该系统可在 CED 手术期间实现真正无框架的多模态图像引导。
在实时荧光透视引导下，使用先前通过锥形束 CT（CBCT）和 MRI 获得的成像数据将微套管放置到五只绵羊的纹状体中，从而实现了三维导航。引入套管后，进行高分辨率 CBCT 检查，并与 MRI 进行配准，以确认套管尖端的位置，并进行必要的调整。腺相关病毒载体-10，旨在递送短发夹 micro RNA（shRNAmir），与 2.0 mM 钆（Gd）混合，并以 3 μl/min 的速度输注 100 μl。完成后，将动物转移到磁共振扫描仪中，通过测量 Gd 扩散的体积来评估大致的分布情况。
在多模态图像引导下成功引入了套管。高分辨率 CBCT 能够验证套管的位置，并且 CED 后的 Gd 增强 MRI 证实了治疗的局部给药。
在多模态图像引导下，将 CED 的微套管引入五只绵羊的纹状体中。使用 CBCT 可以很好地观察到非合金 300μm 直径的套管尖端，从而可以确认尖端在感兴趣区域的位置。
