Panayiotou Maria, Rhode Kawal S, King Andrew P, Ma Yingliang, Cooklin Michael, O'Neill Mark, Gill Jaswinder, Rinaldi C A, Housden R James
Division of Imaging Sciences and Biomedical Engineering, King's College London, London SE1 7EH, UK.
Phys Med Biol. 2015 Oct 21;60(20):8087-108. doi: 10.1088/0031-9155/60/20/8087. Epub 2015 Oct 1.
Determination of the cardiorespiratory phase of the heart has numerous applications during cardiac imaging. In this article we propose a novel view-angle independent near-real time cardiorespiratory motion gating and coronary sinus (CS) catheter tracking technique for x-ray fluoroscopy images that are used to guide cardiac electrophysiology procedures. The method is based on learning CS catheter motion using principal component analysis and then applying the derived motion model to unseen images taken at arbitrary projections, using the epipolar constraint. This method is also able to track the CS catheter throughout the x-ray images in any arbitrary subsequent view. We also demonstrate the clinical application of our model on rotational angiography sequences. We validated our technique in normal and very low dose phantom and clinical datasets. For the normal dose clinical images we established average systole, end-expiration and end-inspiration gating success rates of 100%, 85.7%, and 92.3%, respectively. For very low dose applications, the technique was able to track the CS catheter with median errors not exceeding 1 mm for all tracked electrodes. Average gating success rates of 80.3%, 71.4%, and 69.2% were established for the application of the technique on clinical datasets, even with a dose reduction of more than 10 times. In rotational sequences at normal dose, CS tracking median errors were within 1.2 mm for all electrodes, and the gating success rate was 100%, for view angles from RAO 90° to LAO 90°. This view-angle independent technique can extract clinically useful cardiorespiratory motion information using x-ray doses significantly lower than those currently used in clinical practice.
确定心脏的心肺相位在心脏成像过程中有众多应用。在本文中，我们提出了一种新颖的、与视角无关的近实时心肺运动门控和冠状窦（CS）导管跟踪技术，用于指导心脏电生理程序的X射线荧光透视图像。该方法基于使用主成分分析来学习CS导管的运动，然后利用对极约束将导出的运动模型应用于任意投影下获取的未见图像。此方法还能够在任意后续视角的整个X射线图像中跟踪CS导管。我们还展示了我们的模型在旋转血管造影序列上的临床应用。我们在正常剂量和极低剂量的体模及临床数据集中验证了我们的技术。对于正常剂量的临床图像，我们分别建立了平均收缩期、呼气末和吸气末门控成功率为100%、85.7%和92.3%。对于极低剂量应用，该技术能够跟踪所有被跟踪电极，其平均误差中位数不超过1毫米。即使剂量降低超过10倍，该技术在临床数据集上的平均门控成功率仍分别为80.3%、71.4%和69.2%。在正常剂量的旋转序列中，对于从右前斜90°到左前斜90°的视角，所有电极的CS跟踪误差中位数在1.2毫米以内，门控成功率为100%。这种与视角无关的技术能够使用比当前临床实践中显著更低的X射线剂量提取临床上有用的心肺运动信息。
