IEEE Trans Med Imaging. 2017 Apr;36(4):1016-1026. doi: 10.1109/TMI.2016.2643635. Epub 2016 Dec 22.
Preterm neonates with a very low birth weight of less than 1,500 grams are at increased risk for developing intraventricular hemorrhage (IVH), which is a major cause of brain injury in preterm neonates. Quantitative measurements of ventricular dilatation or shrinkage play an important role in monitoring patients and evaluating treatment options. 3D ultrasound (US) has been developed to monitor ventricle volume as a biomarker for ventricular changes. However, ventricle volume as a global indicator does not allow for precise analysis of local ventricular changes, which could be linked to specific neurological problems often seen in the patient population later in life. In this work, a 3D+t spatial-temporal deformable registration approachis proposed, which is applied to the analysis of the detailed local changes of preterm IVH neonatal ventricles from 3D US images. In particular, a novel sequential convex/dual optimization algorithm is introduced to extract the optimal 3D+t spatial-temporal deformable field, which simultaneously optimizes the sequence of 3D deformation fieldswhile enjoying both efficiencyand simplicity in numerics. The developed registration technique was evaluated by comparing two manually extracted ventricle surfaces from the baseline and the registered follow-up images using the metrics of Dice similarity coefficient (DSC), mean absolute surface distance (MAD), and maximum absolute surface distance (MAXD). The performed experiments using 14 patients with 5 time-point images per patient show that the proposed 3D+t registration approach accurately recovered the longitudinal deformation of ventricle surfaces from 3D US images. The proposed approach may be potentially used to analyse the change pattern of cerebral ventricles of IVH patients, their response to different treatment options, and to elucidate the deficiencies that a patient could have later in life. To the best of our knowledge, this paper reports the first study on the longitudinalanalysis of neonatal ventricular system from 3D US images.
出生体重极低（<1500 克）的早产儿发生脑室出血（IVH）的风险增加，脑室出血是早产儿脑损伤的主要原因。对脑室扩张或缩小的定量测量在监测患者和评估治疗方案方面发挥着重要作用。三维超声（US）已被开发用于监测脑室容积，作为脑室变化的生物标志物。然而，作为全局指标的脑室容积无法对局部脑室变化进行精确分析，而这些变化可能与特定的神经问题有关，这些问题在患者生命后期经常出现。在这项工作中，提出了一种 3D+t 时空可变形配准方法，该方法应用于分析从 3DUS 图像中早产儿 IVH 新生儿脑室的详细局部变化。特别是，引入了一种新的序列凸/对偶优化算法，以提取最佳的 3D+t 时空可变形场，该算法在优化 3D 变形场序列的同时，在数值上兼具效率和简单性。通过使用 Dice 相似系数（DSC）、平均绝对表面距离（MAD）和最大绝对表面距离（MAXD）等指标，将比较基线和配准后的随访图像的两个手动提取的脑室表面，评估所开发的配准技术。对 14 名患者的 5 次时间点图像进行的实验表明，所提出的 3D+t 配准方法可以准确地从 3DUS 图像中恢复心室表面的纵向变形。该方法可能用于分析 IVH 患者的脑室内变化模式、对不同治疗方案的反应，并阐明患者生命后期可能存在的缺陷。据我们所知，这是第一篇关于从 3DUS 图像对新生儿脑室系统进行纵向分析的研究。
