Magnetic Resonance Imaging (MRI) is a well-established modality for pre-operative planning and is also explored for intra-operative guidance of procedures such as intravascular interventions. Among the experimental robot-assisted technologies, the magnetic field gradients of the MRI scanner are used to power and maneuver ferromagnetic applicators for accessing sites in the patient's body via the vascular network. In this work, we propose a computational platform for preoperative planning and modeling of MRI-powered applicators inside blood vessels. This platform was implemented as a two-way data and command pipeline that links the MRI scanner, the computational core, and the operator. The platform first processes multi-slice MR data to extract the vascular bed and then fits a virtual corridor inside the vessel. This corridor serves as a virtual fixture (VF), a forbidden region for the applicators to avoid vessel perforation or collision. The geometric features of the vessel centerline, the VF, and MRI safety compliance (dB/dt, max available gradient) are then used to generate magnetic field gradient waveforms. Different blood flow profiles can be user-selected, and those parameters are used for modeling the applicator's maneuvering. The modeling module further generates cues about whether the selected vascular path can be safely maneuvered. Given future experimental studies that require a real-time operation, the platform was implemented on the Qt framework (C/C++) with software modules performing specific tasks running on dedicated threads: PID controller, generation of VF, generation of MR gradient waveforms.

翻译：磁共振成像（MRI）是一种成熟的术前规划模态，同时也在探索用于血管内介入等手术的术中引导。在实验性机器人辅助技术中，MRI扫描仪的磁场梯度被用于驱动和操控铁磁施放器，以通过血管网络进入患者体内的目标部位。本研究提出了一种用于血管内MRI驱动施放器的术前规划与建模计算平台。该平台实现为连接MRI扫描仪、计算核心与操作者的双向数据与指令管道。平台首先处理多层MRI数据以提取血管床，进而在血管内部拟合虚拟通道。该通道作为虚拟夹具（VF），即施放器需避开的禁止区域，以避免血管穿孔或碰撞。随后利用血管中心线的几何特征、VF及MRI安全合规参数（dB/dt、最大可用梯度）生成磁场梯度波形。用户可选择不同的血流剖面，这些参数将用于施放器操控建模。建模模块进一步生成关于选定血管路径能否安全操控的提示信息。考虑到未来需要实时操作的实验研究，本平台基于Qt框架（C/C++）实现，执行特定任务的软件模块运行于专用线程：PID控制器、VF生成模块及MRI梯度波形生成模块。