Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
Phys Med Biol. 2010 Mar 7;55(5):N133-40. doi: 10.1088/0031-9155/55/5/N02. Epub 2010 Feb 10.
In this study, we demonstrate the proof of principle of the University Medical Center Utrecht (UMCU) robot dedicated to magnetic resonance imaging (MRI)-guided interventions in patients. The UMCU robot consists of polymers and non-ferromagnetic materials. For transperineal prostate interventions, it can be placed between the patient's legs inside a closed bore 1.5T MR scanner. The robot can manually be translated and rotated resulting in five degrees of freedom. It contains a pneumatically driven tapping device to automatically insert a needle stepwise into the prostate using a controller unit outside the scanning room. To define the target positions and to verify the needle insertion point and the needle trajectory, a high-resolution 3D balanced steady state free precession (bSSFP) scan that provides a T2/T1-weighted contrast is acquired. During the needle insertion fast 2D bSSFP images are generated to track the needle on-line. When the target position is reached, the radiation oncologist manually places a fiducial gold marker (small seed) at this location. In total two needle trajectories are used to place all markers. Afterwards, a high-resolution 3D bSSFP scan is acquired to visualize the fiducial gold markers. Four fiducial gold markers were placed transperineally into the prostate of a patient with a clinical stage T3 prostate cancer. In the generated scans, it was possible to discriminate the patient's anatomy, the needle and the markers. All markers were delivered inside the prostate. The procedure time was 1.5 h. This study proves that MRI-guided needle placement and seed delivery in the prostate with the UMCU robot are feasible.
在本研究中，我们证明了乌得勒支大学医学中心（UMCU）机器人用于在患者中进行磁共振成像（MRI）引导介入的原理验证。UMCU 机器人由聚合物和非铁磁材料组成。对于经会阴前列腺介入，它可以放置在患者两腿之间的封闭孔 1.5T MRI 扫描仪内。机器人可以手动平移和旋转，产生五个自由度。它包含一个气动驱动的敲击装置，可使用扫描室外的控制器单元自动将针逐步插入前列腺。为了定义目标位置并验证针插入点和针轨迹，获取了提供 T2/T1 加权对比的高分辨率 3D 平衡稳态自由进动（bSSFP）扫描。在针插入过程中，快速生成 2D bSSFP 图像以在线跟踪针。当到达目标位置时，放射肿瘤学家手动将基准金标记物（小种子）放置在该位置。总共使用两条针轨迹来放置所有标记物。之后，获取高分辨率 3D bSSFP 扫描以可视化基准金标记物。将四个基准金标记物经会阴放置在一位临床 T3 期前列腺癌患者的前列腺中。在所生成的扫描中，可以区分患者的解剖结构、针和标记物。所有标记物都被输送到前列腺内。该过程用时 1.5 小时。本研究证明了使用 UMCU 机器人进行 MRI 引导的前列腺内针放置和种子输送是可行的。
