Rashidinejad Paria, Hu Xiao, Russell Stuart
Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA, United States of America.
Division of Health Systems Analytics School of Nursing, Duke University; Department of Electrical Computer Engineering, Department of Biomedical Engineering, Pratt School of Engineering, Duke University; Department of Neurology, Department of Surgery, Department of Biostatistics and Bioinformatics, School of Medicine, Duke University, Durham, NC, United States of America.
Physiol Meas. 2020 Nov 6;41(10):104003. doi: 10.1088/1361-6579/abbcbb.
We present a framework for analyzing the morphology of intracranial pressure (ICP). The analysis of ICP signals is challenging due to the non-linear and non-Gaussian characteristics of the signal dynamics, inevitable corruption by noise and artifacts, and variations in ICP pulse morphology among individuals with different neurological conditions. Existing frameworks make unrealistic assumptions regarding ICP dynamics and are not tuned for individual patients.
We propose a dynamic Bayesian network for automated detection of three major ICP pulsatile components. The proposed model captures the non-linear and non-Gaussian dynamics of ICP morphology and further adapts to a patient as the individual's ICP measurements are received. To make the approach more robust, we leverage evidence reversal and present an inference algorithm to obtain the posterior distribution over the locations of pulsatile components.
We evaluate our approach on a dataset with over 700 h of recordings from 66 neurological patients, where the pulsatile components were annotated by prior studies. The algorithm obtains accuracies of 96.56%, 92.39%, and 94.04% for the detection of each pulsatile component in the test set, showing significant improvement over existing approaches.
Continuous ICP monitoring is essential in guiding the treatment of neurological conditions such as traumatic brain injuries. An automated approach for ICP morphology analysis is a step towards enhancing patient care with minimal supervision. Compared to previous methods, our framework offers several advantages. It learns the parameters that model each patient's ICP in an unsupervised manner, resulting in an accurate morphology analysis. The Bayesian model-based framework provides uncertainty estimates and reveals interesting facts about the ICP dynamics. The framework can readily be applied to replace existing morphological analysis methods and support the use of ICP pulse morphological features to aid the monitoring of pathophysiological changes of relevance to the care of patients with acute brain injuries.
我们提出了一个用于分析颅内压(ICP)形态的框架。由于信号动态的非线性和非高斯特性、不可避免的噪声和伪迹干扰以及不同神经状况个体之间ICP脉冲形态的差异,ICP信号分析具有挑战性。现有的框架对ICP动态做出了不切实际的假设,并且没有针对个体患者进行调整。
我们提出了一种动态贝叶斯网络,用于自动检测ICP的三个主要搏动成分。所提出的模型捕捉了ICP形态的非线性和非高斯动态,并随着个体的ICP测量值的接收而进一步适应患者。为了使该方法更稳健,我们利用证据反转并提出一种推理算法,以获得搏动成分位置上的后验分布。
我们在一个包含来自66名神经科患者的700多小时记录的数据集上评估了我们的方法,其中搏动成分已由先前的研究进行了标注。该算法在测试集中检测每个搏动成分的准确率分别为96.56%、92.39%和94.04%,显示出比现有方法有显著改进。
持续的ICP监测对于指导创伤性脑损伤等神经疾病的治疗至关重要。一种用于ICP形态分析的自动化方法是朝着以最少监督加强患者护理迈出的一步。与先前的方法相比,我们的框架具有几个优点。它以无监督的方式学习对每个患者的ICP进行建模的参数,从而实现准确的形态分析。基于贝叶斯模型的框架提供不确定性估计,并揭示有关ICP动态的有趣事实。该框架可以很容易地应用于取代现有的形态分析方法,并支持使用ICP脉冲形态特征来辅助监测与急性脑损伤患者护理相关的病理生理变化。