Because of continuous movement and variation in diameter of the inferior vena cava (IVC) with respiration, the measurements on IVC are labor-intensive and with considerable inter-operator variations. Some computer-assisted techniques have been developed to track the movement of the IVC semi-automatically. However, existing methods predominantly rely on reference marker selection and require many manual inputs. In this study, we developed a cross-correlation (CC)-based method for automated IVC movement tracking and measurement, which requires minimal manual input and avoids manual selection of reference markers. Based on the CC method, two approaches, named direct and relative approaches, were used to calculate the maximum, minimum, and variation of the IVC diameter, and compared with the manual measurement. Fifty-four ultrasound cine-loops collected from nine pigs were tested. The results reveal that both the proposed approaches were well agreed with the manual measurement. The errors of the direct approach were less than 9%, while those of relative approach were as high as 26.7%. It is concluded that the proposed direct approach is superior for IVC diameter measurements, which can be comparable with manual counterpart, serving as an alternative to traditional IVC measurement.

中文翻译：

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下腔静脉的自动超声测量：一项动物研究

由于下腔静脉 (IVC) 的直径随着呼吸的持续运动和变化，下腔静脉的测量是劳动密集型的，并且具有相当大的操作者​​间差异。已经开发了一些计算机辅助技术来半自动地跟踪 IVC 的运动。然而，现有方法主要依赖于参考标记选择并且需要许多手动输入。在这项研究中，我们开发了一种基于互相关 (CC) 的自动 IVC 运动跟踪和测量方法，该方法需要最少的手动输入并避免手动选择参考标记。基于CC法，采用直接法和相对法两种方法计算下腔静脉直径的最大值、最小值和变化，并与人工测量进行比较。测试了从 9 头猪收集的 54 个超声波电影循环。结果表明，所提出的两种方法都与手动测量非常吻合。直接法误差小于9%，相对法误差高达26.7%。得出的结论是，所提出的直接方法对于 IVC 直径测量是优越的，可以与手动对应物相媲美，作为传统 IVC 测量的替代方法。