标题： 用于提取早产儿脑氧饱和度信号中去饱和瞬态的稀疏去噪方法 显示英文标题

标题： Sparse-Denoising Methods for Extracting Desaturation Transients in Cerebral Oxygenation Signals of Preterm Infants

摘要： 早产儿在出生后的最初几天内由于脑部供氧不足而面临发展脑损伤的高风险。近红外光谱（NIRS）是一种已建立的技术，用于监测局部组织氧合情况。对脑部NIRS信号的详细波形分析可能提高该方法在准确预测脑损伤方面的临床实用性。在极早产儿中经常观察到短暂的脑部氧饱和度下降，但其临床意义仍不清楚。本研究的目的是检查并比较两种不同方法在分离和提取NIRS信号中短暂偏移方面的性能。我们优化了三种不同的同时低通滤波和总变分去噪（LPF_TVD）方法，并将其性能与一种最近提出的使用奇异谱分析和离散余弦变换（SSA_DCT）的方法进行了比较。LPF_TVD方法的参数通过使用合成NIRS-like信号的网格搜索进行优化。SSA_DCT方法通过一个后处理过程进行了修改，以增加提取成分的稀疏性。我们的分析使用了一个合成的NIRS-like数据集，结果显示LPF_TVD方法优于修改后的SSA_DCT方法：LPF_TVD方法的中位均方误差为0.97（95% CI：0.86至1.07），低于修改后的SSA_DCT方法的1.48（95% CI：1.33至1.63），P<0.001。双低通滤波和总变分去噪方法比SSA_DCT方法计算效率高3到4个数量级。需要更多的研究来检查这些方法在提取真实NIRS信号中的氧饱和度下降的效果。 显示英文摘要

摘要： Preterm infants are at high risk of developing brain injury in the first days of life as a consequence of poor cerebral oxygen delivery. Near-infrared spectroscopy (NIRS) is an established technology developed to monitor regional tissue oxygenation. Detailed waveform analysis of the cerebral NIRS signal could improve the clinical utility of this method in accurately predicting brain injury. Frequent transient cerebral oxygen desaturations are commonly observed in extremely preterm infants, yet their clinical significance remains unclear. The aim of this study was to examine and compare the performance of two distinct approaches in isolating and extracting transient deflections within NIRS signals. We optimized three different simultaneous low-pass filtering and total variation denoising (LPF_TVD) methods and compared their performance with a recently proposed method that uses singular-spectrum analysis and the discrete cosine transform (SSA_DCT). Parameters for the LPF_TVD methods were optimized over a grid search using synthetic NIRS-like signals. The SSA_DCT method was modified with a post-processing procedure to increase sparsity in the extracted components. Our analysis, using a synthetic NIRS-like dataset, showed that a LPF_TVD method outperformed the modified SSA_DCT method: median mean-squared error of 0.97 (95% CI: 0.86 to 1.07) was lower for the LPF_TVD method compared to the modified SSA_DCT method of 1.48 (95% CI: 1.33 to 1.63), P<0.001. The dual low-pass filter and total variation denoising methods are considerably more computational efficient, by 3 to 4 orders of magnitude, than the SSA_DCT method. More research is needed to examine the efficacy of these methods in extracting oxygen desaturation in real NIRS signals.