Quantitative assessment of carotid ultrasound diameter measurements in the operating room: a comparable analysis of long-axis versus rotated and tilted orientation
This study aimed to quantitatively assess common carotid diameter estimates obtained in a clinical setting from an RT view and compare those to corresponding estimates obtained using other views. Approach. Carotid US measurements were performed in 30 adult cardiac-surgery patients (26 males, 4 females) with short-axis (SA), LA, and RT probe orientations, the first being used as a reference for measuring the true vessel diameter. Per 30 s acquisition, the median and spread in diameter values were computed, the latter representing a measure of robustness, and were statistically compared between views. Main results. The media...
Source: Physiological Measurement - March 20, 2024 Category: Physiology Authors: Esm ée C de Boer, Catarina Dinis Fernandes, Danihel van Neerven, Christoph Pennings, Rohan Joshi, Sabina Manzari, Sergei Shulepov, Luuk van Knippenberg, John van Rooij, R Arthur Bouwman and Massimo Mischi Source Type: research
SwinUNet: a multiscale feature learning approach to cardiovascular magnetic resonance parametric mapping for myocardial tissue characterization
This study aims to accelerate CMR parametric mapping with deep learning. Approach. A deep-learning model, SwinUNet, was developed to accelerate T1/T2 mapping. SwinUNet used a convolutional UNet and a Swin transformer to form a hierarchical 3D computation structure, allowing for analyzing CMR images spatially and temporally with multiscale feature learning. A comparative study was conducted between SwinUNet and an existing deep-learning model, MyoMapNet, which only used temporal analysis for parametric mapping. The T1/T2 mapping performance was evaluated globally using mean absolute error (MAE) and structural similarity ind...
Source: Physiological Measurement - March 20, 2024 Category: Physiology Authors: Yifan Qi, Fusheng Wang, Jun Kong, J Jane Cao and Yu Y Li Source Type: research
Increasing accuracy of pulse arrival time estimation in low frequency recordings
Objective. Wearable devices that measure vital signals using photoplethysmography are becoming more commonplace. To reduce battery consumption, computational complexity, memory footprint or transmission bandwidth, companies of commercial wearable technologies are often looking to minimize the sampling frequency of the measured vital signals. One such vital signal of interest is the pulse arrival time (PAT), which is an indicator of blood pressure. To leverage this non-invasive and non-intrusive measurement data for use in clinical decision making, the accuracy of obtained PAT-parameters needs to increase in lower sampling ...
Source: Physiological Measurement - March 12, 2024 Category: Physiology Authors: Roel J H Montree, Elisabetta Peri, Reinder Haakma, Lukas R C Dekker and Rik Vullings Source Type: research
Quantifying the accuracy of inter-beat intervals acquired from consumer-grade photoplethysmography wristbands using an electrocardiogram-aided information-based similarity approach
In this study, 30 healthy participants concurrently wore two wristbands (E4 and Honor 5) and a gold-standard electrocardiogram (ECG) device under four conditions: resting, deep breathing with a frequency of 0.17 Hz and 0.1 Hz, and mental stress tasks. To quantitatively validate the accuracy of IBI acquired from PPG wristbands, this study proposed to apply an information-based similarity (IBS) approach to quantify the pattern similarity of the underlying dynamical temporal structures embedded in IBI time series simultaneously recorded using PPG wristbands and the ECG system. The occurrence frequency of basic patterns and th...
Source: Physiological Measurement - March 11, 2024 Category: Physiology Authors: Xingran Cui, Jing Wang, Shan Xue, Zeguang Qin and Chung-Kang Peng Source Type: research
SST: a snore shifted-window transformer method for potential obstructive sleep apnea patient diagnosis
The objective of this study was to develop a noncontact sleep audio signal-based method for diagnosing potential OSA patients, aiming to provide a more convenient diagnostic approach compared to the traditional polysomnography (PSG) testing. Approach. The study employed a shifted window transformer model to detect snoring audio signals from whole-night sleep audio. First, a snoring detection model was trained on large-scale audio datasets. Subsequently, the deep feature statistical metrics of the detected snore audio were used to train a random forest classifier for OSA patient diagnosis. Main results. Using a self-collect...
Source: Physiological Measurement - March 11, 2024 Category: Physiology Authors: Jing Luo, Yinuo Zhao, Haiqin Liu, Yitong Zhang, Zhenghao Shi, Rui Li, Xinhong Hei and Xiaorong Ren Source Type: research
A systematic review on automatic identification of insomnia
Conclusion. Based on our review of the studies featured in this paper, we have identified a notable research gap in the current methods for identifying insomnia and opportunities for future advancements in the automation of insomnia detection. While the current techniques have shown promising results, there is still room for improvement in terms of accuracy and reliability. Future developments in technology and machine learning algorithms could help address these limitations and enable more effective and efficient identification of insomnia. (Source: Physiological Measurement)
Source: Physiological Measurement - March 5, 2024 Category: Physiology Authors: Manisha Ingle, Manish Sharma, Kamlesh Kumar, Prince Kumar, Ankit Bhurane, Heather Elphick, Deepak Joshi and U Rajendra Acharya Source Type: research
An interpretable shapelets-based method for myocardial infarction detection using dynamic learning and deep learning
Objective. Myocardial infarction (MI) is a prevalent cardiovascular disease that contributes to global mortality rates. Timely diagnosis and treatment of MI are crucial in reducing its fatality rate. Currently, electrocardiography (ECG) serves as the primary tool for clinical diagnosis. However, detecting MI accurately through ECG remains challenging due to the complex and subtle pathological ECG changes it causes. To enhance the accuracy of ECG in detecting MI, a more thorough exploration of ECG signals is necessary to extract significant features. Approach. In this paper, we propose an interpretable shapelet-based approa...
Source: Physiological Measurement - March 1, 2024 Category: Physiology Authors: Jierui Qu, Qinghua Sun, Weiming Wu, Fukai Zhang, Chunmiao Liang, Yuguo Chen and Cong Wang Source Type: research
Rapid patient-specific FEM meshes from 3D smart-phone based scans
The objective of this study was to describe and evaluate a smart-phone based method to rapidly generate subject-specific finite element method (FEM) meshes. More accurate FEM meshes should lead to more accurate thoracic electrical impedance tomography (EIT) images. Approach. The method was evaluated on an iPhone ® that utilized an app called Heges, to obtain 3D scans (colored, surface triangulations), a custom belt, and custom open-source software developed to produce the subject-specific meshes. The approach was quantitatively validated via mannequin and volunteer tests using an infrared tracker as the go ld standard, an...
Source: Physiological Measurement - February 28, 2024 Category: Physiology Authors: Ethan K Murphy, Joel Smith, Michael A Kokko, Seward B Rutkove and Ryan J Halter Source Type: research
Detecting central apneas using multichannel signals in premature infants
Objective. Monitoring of apnea of prematurity, performed in neonatal intensive care units by detecting central apneas (CAs) in the respiratory traces, is characterized by a high number of false alarms. A two-step approach consisting of a threshold-based apneic event detection algorithm followed by a machine learning model was recently presented in literature aiming to improve CA detection. However, since this is characterized by high complexity and low precision, we developed a new direct approach that only consists of a detection model based on machine learning directly working with multichannel signals. Approach. The dat...
Source: Physiological Measurement - February 28, 2024 Category: Physiology Authors: Gabriele Varisco, Zheng Peng, Deedee Kommers, Eduardus J E Cottaar, Peter Andriessen, Xi Long and Carola van Pul Source Type: research
Blood flow restriction pressure for narrow cuffs (5 cm) cannot be estimated with precision
Blood flow restriction pressures are set relative to the lowest pressure needed to occlude blood flow with that specific cuff. Due to pressure limitations of some devices, it is often not possible to occlude blood flow in all subjects and apply a known relative pressure in the lower body with a 5 cm wide cuff. Objective. To use a device capable of generating high pressures (up to 907 mmHg) to create and validate an estimation equation for the 5 cm cuff in the lower body using a 12 cm cuff. Approach. 170 participants had their arterial occlusion pressure (AOP) with a 5 cm and 12 cm cuff and their thigh circumference measure...
Source: Physiological Measurement - February 26, 2024 Category: Physiology Authors: Robert W Spitz, Yujiro Yamada, Vickie Wong, Ryo Kataoka, William B Hammert, Jun Seob Song, Anna Kang, Aldo Seffrin and Jeremy P Loenneke Source Type: research
Sampling rate requirement for accurate calculation of heart rate and its variability based on the electrocardiogram
Objective. To develop analytical formulas which can serve as quantitative guidelines for the selection of the sampling rate for the electrocardiogram (ECG) required to calculate heart rate (HR) and heart rate variability (HRV) with a desired level of accuracy. Approach. We developed analytical formulas which relate the ECG sampling rate to conservative bounds on HR and HRV errors: (i) one relating HR and sampling rate to a HR error bound and (ii) the others relating sampling rate to HRV error bounds (in terms of root-mean-square of successive differences (RMSSD) and standard deviation of normal sinus beats (SDNN)). We vali...
Source: Physiological Measurement - February 21, 2024 Category: Physiology Authors: Yuanyuan Zhou, Bryndan Lindsey, Samantha Snyder, Elizabeth Bell, Lucy Reider, Michael Vignos, Eyal Bar-Kochba, Azin Mousavi, Jesse Parreira, Casey Hanley, Jae Kun Shim and Jin-Oh Hahn Source Type: research
Analysis of electrode arrangements for brain stroke diagnosis via electrical impedance tomography through numerical computational models
In this study, we analyzed the impact of electrodes in realistic numerical models by (1) investigating the effect of individual electrodes on the resulting simulated EIT boundary measurements and (2) testing the performance of different electrode arrangements using a machine learning classification model. Main results. We found that, as expected, the electrodes deemed most significant in detecting stroke depend on the location of the electrode relative to the stroke lesion, as well as the role of the electrode. Despite this dependence, there are notable electrodes used in the models that are consistently considered to be t...
Source: Physiological Measurement - February 19, 2024 Category: Physiology Authors: Hannah Lee, Jared Culpepper and Emily Porter Source Type: research
Utilization of bioelectrical impedance vector analysis (BIVA) in children and adolescents without diagnosed diseases: a systematic review
Conclusion. Nutricional status and body composition were the main studies objectives. References values were not always adequate or specific for the sample and population. Furthermore, there was no pattern of pre-test recommendations among the studies. (Source: Physiological Measurement)
Source: Physiological Measurement - February 19, 2024 Category: Physiology Authors: Leandro Narciso Santiago, Priscila Cust ódio Martins and Diego Augusto Santos Silva Source Type: research
Evaluation of adjacent and opposite current injection patterns for a wearable chest electrical impedance tomography system
This study aims to evaluate the performance of current injection patterns with various low-amplitude currents in healthy volunteers. Approach. A total of 96 test sets of EIT measurement was recorded in 12 healthy subjects by employing adjacent and opposite current injection patterns with four amplitudes of small current (i.e. 1 mA, 500 uA, 250 uA and 125 uA). The performance of the two injection patterns with various currents was evaluated in terms of signal-to-noise ratio (SNR) of thorax impedance, EIT image metrics and EIT-based clinical parameters. Main results. Compared with adjacent injection, opposite injection had h...
Source: Physiological Measurement - February 15, 2024 Category: Physiology Authors: Lin Yang, Zhijun Gao, Chunchen Wang, Hang Wang, Jing Dai, Yang Liu, Yilong Qin, Meng Dai, Xinsheng Cao and Zhanqi Zhao Source Type: research
Foundation models for physiological data, how to develop them, and what to expect of them
(Source: Physiological Measurement)
Source: Physiological Measurement - February 14, 2024 Category: Physiology Authors: Xiao Hu Source Type: research
