分娩监护分析系统的研制

分娩监护分析系统由宫缩压力传感器，宫缩信号检测处理电路，多普勒超声探头，胎心率检测处理电路，微型计算机系统等构成，其软件包括实时监测，预诊分析，实验分析和系统维护四大模块，系统可以实时检测，存储和图文显示分娩过程中的胎心率和宫外宫缩信息，所存储的现场信息可以动态回放，作回顾分析研究。     

一种基于织物电极的可穿戴心电采集系统的设计

本研究设计了一种高精度可穿戴心电采集系统,该系统由心电模拟前端电路、数字滤波及控制电路和系统软件三部分组成.其采用软硬件滤波来消除基线漂移、皮肤接触噪声及运动伪迹等干扰,并设计嵌入聚吡咯织物电极的心电衣来增加穿戴舒适性.经与两款同类型心电监护仪相比,结果表明:本系统准确度较高,功耗较低,且能稳定可靠的对心电进行长时间监测,并能通过蓝牙实现无线传输.     

胎心音存储回放系统设计

目的基于STM32F103R8T6微处理器的胎心音存储及回放系统的设计。方法采用STM32单片机作为系统主控模块；SD作为存储介质，存储拾取的胎心音、胎心率及信号波形；系统移植FAT32文件系统，数据以文件格式存储；采用CP2102实现USB接口。同时该系统在秦皇岛市友谊医院进行了为期5d的临床试用，以验证设计效果。结果系统可在检测胎心率的同时，将所需时段的数据进行存储；可调取存储的数据进行回放；还可以将存储的数据上传至上位机，实现打印输出。临床应用证明，系统符合设计需求。结论系统设计能够实现胎心音的存储及回放，满足设计需求。     

用于数字等温扩增系统的荧光图像分析技术

基于微流控芯片的数字等温扩增技术作为一种新型分子检测技术，可以通过对采集到的荧光图像进行特定的图像处理，以实现对待测目标的绝对定量分析。本研究利用本课题组研制的数字微流控芯片所采集到的荧光图像为分析对象，并结合实际应用环境，开发出配套的软件分析系统。该系统中的荧光图像处理分析部分具备图像拼接、图像倾斜校正、目标区域的截取、图像分割以及荧光亮点计数等功能。该系统能很好地满足核酸分子数检测的需求，并具有良好的人机交互性能。结果表明该系统的分析结果与Image J图像处理软件的统计结果不仅具有一致性，而且能够对检测到的结果实现自动化的计算分析，这为该款软件分析系统的广泛应用奠定了坚实的基础。     

基于Android手机的生理参数移动监测系统

本研究设计了一款基于Android手机的人体生理参数移动监测系统。依据心电信号与脉搏波信号的特点,设计硬件采集系统。利用蓝牙无线通信方式,将硬件电路采集的生理信号发送至手机。通过在Android手机上开发的应用程序,实现心电信号和脉搏波信号的数字滤波处理、实时显示、存储及回显等功能。通过测量的脉搏波传导时间建立连续血压计算模型,并与人体血压实测值进行验证测试。最后在多个品牌的Android手机上运行本系统的应用程序,验证该系统的实用性和兼容性。该系统具有体积小巧、成本低、可实时连续监测的优点,实现了连续生理参数监测。     

全数字超声多普勒血流测量系统研究

传统超声多普勒血流测量仪器使用模拟电路来完成信号采集与解调处理,此类系统容易受外界电磁环境、温度变化等因素的干扰,也难以运用现代信号处理技术来实现更高级的检测功能,例如多深度检测、功率M型多普勒血流成像以及编码激励成像等。本研究设计了一种全数字的超声多普勒血流信号采集处理系统,结合经典的自相关技术,实现了多深度检测和功率M型多普勒血流成像,并采用2周期基础码调制的13位Barker码编码激励方法,得到远高于传统方法的轴向空间分辨率。为验证该系统的有效性,首先利用该系统对多普勒体模进行检测实验研究,证明该系统能有效提高轴向空间分辨率;然后通过对大脑中动脉、前动脉血流检测,表明该系统可以显示出超声波发射方向上整个深度的血流信息,有利于血管的定位和识别。     

胎心率远程监护系统的中心站设计

本文介绍了一种基于电话网的胎心率远程监护系统,它主要由前端胎心率检测仪、医院中心站组成。中心站通过Ｍｏｄｅｍ和公共电话网接收前端胎心率检测仪的数据,并对数据进行计算机辅助分析,在医生的参与下完成诊断过程。     

多通道经络电学检测系统的研制

为了解决经络研究中的信息检测问题,我们研制成功了“多通道经络信息检测系统”。该系统是以微机为基础的实时多点检测装置。系统硬件包括:电极系统、模拟部分、接口电路和微机系统。软件部分为自编的开放式专用软件,可灵活地调用诸如GRAPHTOOL等数据处理软件进行数据处理。 电极系统采用Ag-AgCl防极化电极。模拟部分包括:高阻抗程控隔离放大器、低通虑波器。接口电路包括:多路同步采/保电路、多路变换器、V/I-I/V转换器和A/D变换器以及译码器等。微机系统包括:主机、显示器、打印机、键盘、鼠标等。机型要求在386及以上。本系统具备:高增益,0-60dB程控;高输入阻抗,100MΩ;高共模抑制比,100dB;较低噪声和高安全性。通过科研实际使用证明本系统设计合理,工作稳定。整个过程采用人机对话方式,易于操作,具有灵活的数据处理能力。本系统除可以用于经络电学特性的研究外,配以不同的传感器,可以进行经络的光学、机械以及化学等特性的研究。本系统既是经络实验研究的有力工具,又在临床上具有广阔的应用前景。     

数字助听器算法开发平台pDHA的构建和测试

数字助听器是目前广大聋人康复的唯一有效手段,因此数字助听算法的研究日益重要.为便于进行助听算法的开发测试,本论文设计实现了一款基于可编程DSP的全数字助听算法开发平台pDHA.该平台具有计算功能强大、实时便携、扩展能力丰富等特点.本论文还针对此类平台的独特应用需求和相关标准,制定了一套完整的测试流程.参数测试结果表明,该系统具备足够的能力进行高级数字助听算法的开发和测试.     

一种胎心率基线修正算法

对于胎心率分析和胎儿状况评估而言,胎心率基线估计十分重要。为了使现有胎心率基线更为准确、更符合胎心率曲线,本文提出了一种胎心率基线修正算法。首先,本算法找出并修正现有胎心率基线中的偏差部分,再对整条基线进行多次平滑,最后得到修正后的基线。为了评估基线修正算法的性能表现,本文将一种胎心率基线估计算法和基线修正算法结合在一起,并与两种现有的基线估计算法进行了比较。结果表明,包含基线修正算法在内的基线评估算法在分析准确性、运算效率方面均有不错表现,这也证实基线修正算法的有效性。     

Simultaneity of foetal heart rate acceleration and foetal trunk movement determined by foetal magnetocardiogram actocardiography

We describe a new method of actocardiography, foetal magnetocardiogram (fMCG) actocardiography, which is based on the high sensitivity of the fMCG to foetal trunk movements. We demonstrate the efficacy of the method by applying it to assess the simultaneity of onset of foetal heart rate (FHR) acceleration and foetal trunk movement. The analysis was restricted to events for which the onset of FHR accelerations and foetal movements could be determined accurately, i.e. when FHR was stable and near the average quiescent level just prior to the acceleration. We found that FHR accelerations coincided with or preceded foetal movements nearly all the time. This supports the hypothesis of coordinated control of FHR accelerations and foetal movements more strongly than prior studies, based on other techniques. We also found that beat-to-beat FHR variability often decreased at or near the start of FHR accelerations and that this occurrence was an accurate marker of foetal movement onset, even when foetal movement onset lagged FHR accelerations.     

Computerised electronic foetal heart rate monitoring in labour: automated contraction identification

The foetal heart rate (FHR) response to uterine contractions is crucial to detect foetal distress by electronic FHR monitoring during labour. We are developing a new automated system (OxSys) for decision support in labour, using the Oxford database of intrapartum FHR records. We describe here a novel technique for automated detection of uterus contractions. In addition, we present a comparison of the new method with four other computerised approaches. During training, OxSys achieved sensitivity above 95% and positive predictive value (PPV) of up to 90% for traces of good quality. During testing, OxSys achieved sensitivity = 87% and PPV = 75%. For comparison, a second clinical expert obtained sensitivity = 93% and PPV = 80%, and all other computerised approaches achieved lower values. It was concluded that the proposed method can be employed with confidence in our study on foetal health assessment in labour and future OxSys development.     

The effects of maternal depression on fetal heart rate response to vibroacoustic stimulation

To better understand the effects of untreated maternal depression on the fetus, this study examined fetal heart rate (FHR) and FHR reactivity to vibroacoustic stimulation in pregnant women with untreated depression. The 20 participants were 32- to 36-week pregnant women divided into groups with depression (N = 10) and without depression (N = 10) based on the Beck Depression Inventory (BDI; Beck, 1977; Beck & Steer, 1987). Participants were attached to a fetal heart monitor, and 10 min of baseline FHR were recorded. A vibroacoustic stimulus (VAS) was presented, and an additional 10 min of FHR were recorded. Fetuses of mothers with depression had an elevated baseline FHR and a 3.5-fold delay in return to baseline FHR after VAS presentation. Additionally, mothers with depression had significantly higher anxiety levels and took fewer prenatal vitamins during pregnancy. Delayed habituation of FHR in the fetuses of mothers with depression may be due to alterations in the internal hormonal environment and could have implications for postnatal information processing.     

The Effects of Maternal Depression on Fetal Heart Rate Response to Vibroacoustic Stimulation

To better understand the effects of untreated maternal depression on the fetus, this study examined fetal heart rate (FHR) and FHR reactivity to vibroacoustic stimulation in pregnant women with untreated depression. The 20 participants were 32- to 36-week pregnant women divided into groups with depression (N = 10) and without depression (N = 10) based on the Beck Depression Inventory (BDI; Beck, 1977; Beck & Steer, 1987). Participants were attached to a fetal heart monitor, and 10 min of baseline FHR were recorded. A vibroacoustic stimulus (VAS) was presented, and an additional 10 min of FHR were recorded. Fetuses of mothers with depression had an elevated baseline FHR and a 3.5-fold delay in return to baseline FHR after VAS presentation. Additionally, mothers with depression had significantly higher anxiety levels and took fewer prenatal vitamins during pregnancy. Delayed habituation of FHR in the fetuses of mothers with depression may be due to alterations in the internal hormonal environment and could have implications for postnatal information processing.     

步态仪中的分区域编码测量方法

步态分析是当代生物医学工程的一项重要技术,采用超声传感器建立起来的人体关节运动轨迹测量仪,必须克服超声传感器方向性对测量范围的限制,本文提出的分区域编码测量方法,解决了这个问题,扩充了人体运动的测量范围.     

Complexity analysis of the fetal heart rate variability: early identification of severe intrauterine growth-restricted fetuses

The main goal of this work is to suggest new indices for a correct identification of the intrauterine growth-restricted (IUGR) fetuses on the basis of fetal heart rate (FHR) variability analysis performed in the antepartum period. To this purpose, we analyzed 59 FHR time series recorded in early periods of gestation through a Hewlett Packard 1351A cardiotocograph. Advanced analysis techniques were adopted including the computation of the Lempel Ziv complexity (LZC) index and the multiscale entropy (MSE), that is, the entropy estimation with a multiscale approach. A multiparametric classifier based on k-mean cluster analysis was also performed to separate pathological and normal fetuses. The results show that the proposed LZC and the MSE could be useful to identify the actual IUGRs and to separate them from the physiological fetuses, providing good values of sensitivity and accuracy (Se = 77.8%, Ac = 82.4%).     

数字双波束合成孔径超声成像方法的研究与实现

以提高超声诊断系统的性／价比为目标,提出了一种数字化超声图像合成的新方法,利用双波束合成技术将帧频加倍和利用合成孔径技术将接收通道个数减半。在分析和仿真的基础上,详细地讨论了其硬件设计的要点,并进行了实验验证。实验结果表明,该方法且不损失帧频和图像质量,可显著降低系统成本。     

An algorithm for the recovery of fetal heart rate series from CTG data

Cardiotocography (simultaneous recording of fetal heart rate (FHR) and uterine contractions) is one of the most used diagnostic techniques to evaluate fetal well-being and to investigate the functional state of the fetal autonomic nervous system. Recently, great interest has been paid to the variability of the FHR, and its frequency analysis, as a base for a more objective analysis of the cardiotocographic (CTG) tracings. FHR signals are unevenly sampled series. To obtain evenly sampled series, cardiotocographs often use zero-order interpolation. Such process is simple and fast but results unsuitable for frequency analyses because it introduces alterations in the FHR power spectrum. An algorithm for the recovery of the true FHR series out of the zero-order interpolated CTG data was developed and evaluated.     

Computer-assisted femoral head resurfacing

Femoral head resurfacing (FHR) is an alternative to total hip replacement (THR) and is particularly suitable for the younger, more active patients. However, this procedure is more difficult than THR, the mechanical jigs routinely used to align the implant produce significant variability in implant placement, and proper positioning process is time-consuming. This paper is concerned with the construction of mathematical model of femoral head and neck and a computer-assisted femoral head resurfacing system. On the basis of numerical optimization theory, a series of mathematical equations are derived to describe the femoral head and neck. By adopting techniques and tools such as optical tracking, numerical analysis, and computer graphics, a 3D digital model of femoral head and neck is reconstructed, and a FHR system is developed. With the aid of this software, visualization and pin placement can be easily achieved. Experimental results in this study show that the FHR system provides a useful tool for performing the femoral head resurfacing surgery quickly and accurately.     

Foetal heart rate power spectrum response to uterine contraction

Cardiotocography is the most diffused prenatal diagnostic technique in clinical routine. The simultaneous recording of foetal heart rate (FHR) and uterine contractions (UC) provides useful information about foetal well-being during pregnancy and labour. However, foetal electronic monitoring interpretation still lacks reproducibility and objectivity. New methods of interpretation and new parameters can further support physicians’ decisions. Besides common time-domain analysis, study of the variability of FHR can potentially reveal autonomic nervous system activity of the foetus. In particular, it is clinically relevant to investigate foetal reactions to UC to diagnose foetal distress early. Uterine contraction being a strong stimulus for the foetus and its autonomic nervous system, it is worth exploring the FHR variability response. This study aims to analyse modifications of the power spectrum of FHR variability corresponding to UC. Cardiotocographic signal tracts corresponding to 127 UC relative to 30 healthy foetuses were analysed. Results mainly show a general, statistically significant (t test, p<0.01) power increase of the FHR variability in the LF 0.03–0.2 Hz and HF 0.2–1 in correspondence of the contraction with respect to a reference tract set before contraction onset. Time evolution of the power within these bands was computed by means of time-varying spectral estimation to concisely show the FHR response along a uterine contraction. A synchronised grand average of these responses was also computed to verify repeatability, using the contraction apex as time reference. Such modifications of the foetal HRV that follow a contraction can be a sign of ANS reaction and, therefore, additional, objective information about foetal reactivity during labour.