Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum Der Charité (DHZC), Berlin, Germany.
Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, Berlin, Germany.
Int J Comput Assist Radiol Surg. 2024 Mar;19(3):553-569. doi: 10.1007/s11548-023-03012-y. Epub 2023 Sep 7.
Numerical phantom methods are widely used in the development of medical imaging methods. They enable quantitative evaluation and direct comparison with controlled and known ground truth information. Cardiac magnetic resonance has the potential for a comprehensive evaluation of the mitral valve (MV). The goal of this work is the development of a numerical simulation framework that supports the investigation of MRI imaging strategies for the mitral valve.
We present a pipeline for synthetic image generation based on the combination of individual anatomical 3D models with a position-based dynamics simulation of the mitral valve closure. The corresponding images are generated using modality-specific intensity models and spatiotemporal sampling concepts. We test the applicability in the context of MRI imaging strategies for the assessment of the mitral valve. Synthetic images are generated with different strategies regarding image orientation (SAX and rLAX) and spatial sampling density.
The suitability of the imaging strategy is evaluated by comparing MV segmentations against ground truth annotations. The generated synthetic images were compared to ones acquired with similar parameters, and the result is promising. The quantitative analysis of annotation results suggests that the rLAX sampling strategy is preferable for MV assessment, reaching accuracy values that are comparable to or even outperform literature values.
The proposed approach provides a valuable tool for the evaluation and optimization of cardiac valve image acquisition. Its application to the use case identifies the radial image sampling strategy as the most suitable for MV assessment through MRI.
数值体模方法广泛应用于医学成像方法的开发。它们能够进行定量评估,并与受控和已知的真实信息进行直接比较。心脏磁共振具有全面评估二尖瓣(MV)的潜力。本工作的目的是开发一个数值模拟框架,支持对二尖瓣的 MRI 成像策略的研究。
我们提出了一种基于个体解剖 3D 模型与二尖瓣闭合位置动力学模拟相结合的合成图像生成流水线。使用与模态相关的强度模型和时空采样概念生成相应的图像。我们在评估二尖瓣的 MRI 成像策略的背景下测试其适用性。针对图像方向(SAX 和 rLAX)和空间采样密度,生成不同策略的合成图像。
通过将 MV 分割与地面真实标注进行比较,评估成像策略的适用性。将生成的合成图像与具有类似参数的采集图像进行比较,结果是有希望的。标注结果的定量分析表明,rLAX 采样策略更适合 MV 评估,其准确度值可与文献值相媲美,甚至超过文献值。
所提出的方法为心脏瓣膜图像采集的评估和优化提供了有价值的工具。其在二尖瓣评估的应用案例中确定了径向图像采样策略是最适合通过 MRI 进行评估的策略。