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1.
Sensors (Basel) ; 24(13)2024 Jun 30.
Article in English | MEDLINE | ID: mdl-39001037

ABSTRACT

Drowsiness is a main factor for various costly defects, even fatal accidents in areas such as construction, transportation, industry and medicine, due to the lack of monitoring vigilance in the mentioned areas. The implementation of a drowsiness detection system can greatly help to reduce the defects and accident rates by alerting individuals when they enter a drowsy state. This research proposes an electroencephalography (EEG)-based approach for detecting drowsiness. EEG signals are passed through a preprocessing chain composed of artifact removal and segmentation to ensure accurate detection followed by different feature extraction methods to extract the different features related to drowsiness. This work explores the use of various machine learning algorithms such as Support Vector Machine (SVM), the K nearest neighbor (KNN), the Naive Bayes (NB), the Decision Tree (DT), and the Multilayer Perceptron (MLP) to analyze EEG signals sourced from the DROZY database, carefully labeled into two distinct states of alertness (awake and drowsy). Segmentation into 10 s intervals ensures precise detection, while a relevant feature selection layer enhances accuracy and generalizability. The proposed approach achieves high accuracy rates of 99.84% and 96.4% for intra (subject by subject) and inter (cross-subject) modes, respectively. SVM emerges as the most effective model for drowsiness detection in the intra mode, while MLP demonstrates superior accuracy in the inter mode. This research offers a promising avenue for implementing proactive drowsiness detection systems to enhance occupational safety across various industries.


Subject(s)
Electroencephalography , Sleep Stages , Support Vector Machine , Humans , Electroencephalography/methods , Sleep Stages/physiology , Algorithms , Electrodes , Signal Processing, Computer-Assisted , Bayes Theorem , Machine Learning
2.
J Back Musculoskelet Rehabil ; 37(4): 1031-1040, 2024.
Article in English | MEDLINE | ID: mdl-38277282

ABSTRACT

BACKGROUND: Cervical traction is effective on pain and function in patients with cervical radiculopathy but its effectiveness on balance disorders has not yet been studied. OBJECTIVE: To evaluate the effect of mechanical intermittent cervical traction (MICT) on stabilometric parameters in patients with cervical radiculopathy. METHODS: This randomized crossover study assigned 20 patients with cervical radiculopathy to one of the two groups: Group effective traction (ET)/sham traction (ST) (n= 10) treated firstly with ET (traction force of 12 Kg) then with ST (traction force of 2 Kg) with one-week interval and group ST/ET (n= 10) treated invertedly with a ST then ET. Each traction procedure was maintained for 10 minutes twice separated by 5 minutes of rest. Patients were assessed before and immediately after MICT procedure. Main outcome measures were stabilometric parameters: center of pressure, sway area and lateral and anteroposterior displacements using a force platform. Secondary outcome measures were pain intensity, grip strength and dizziness. RESULTS: ET has provided a significantly greater improvement in both groups and in the total population in terms of stabilometric parameters (p< 0.01), pain intensity, and grip strength (p< 0.05), compared to ST. CONCLUSION: MICT seems to have an immediate beneficial effect on stabilometric parameters, pain and grip strength in patients with cervical radiculopathy.


Subject(s)
Cross-Over Studies , Postural Balance , Radiculopathy , Traction , Humans , Radiculopathy/physiopathology , Radiculopathy/therapy , Traction/methods , Male , Female , Middle Aged , Postural Balance/physiology , Adult , Cervical Vertebrae/physiopathology , Treatment Outcome , Pain Measurement , Hand Strength/physiology
3.
Libyan J Med ; 17(1): 2082029, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35652803

ABSTRACT

Functional gastrointestinal disorders (FGIDs) are highly prevalent in medical students around the world. However, there is no specific data on FGIDs in Tunisia. The objectives of this study were to evaluate the prevalence of FGIDs in medical students according to the rome III criteria and to identify risk factors associated with these disorders. A self-administered questionnaire survey was carried out among the students from the first and the second year of medical studies. We studied the influence of socio-demographic characteristics, lifestyle, health care seeking, psychosomatic symptoms and hospital anxiety and depression scale on the prevalence of FGIDs among these students. Three hundred and forty-three students (20.3 ± 0.8years) were included in our study. The prevalence of FGIDs was 54.2%. The main FGIDs found were the unspecified functional bowel disorder (46.6%), functional constipation (11.6%), irritable bowel syndrome (7.6%) and functional dyspepsia (6.7%). In logistic regression, abnormal BMI (OR = 2.1, 95% CI= 1-4.3), living in school dormitory (OR = 3.7, 95% CI = 1.7-7.8), low water intake (OR = 2.2, 95% CI = 1.1-4.2), digestive medication use (OR = 3.4, 95% CI= 1.3-8.5), and probable or definite anxiety (OR = 2.5, 95% CI = 1.1-5.8) were the five risk factors associated with FGIDs. We demonstrate a high prevalence of FGIDs (54.2%) among our students. Risk factors for FGIDs were abnormal BMI, living in school dormitory, low water intake, digestive medication use and anxiety.


Subject(s)
Gastrointestinal Diseases , Students, Medical , Gastrointestinal Diseases/diagnosis , Gastrointestinal Diseases/epidemiology , Gastrointestinal Diseases/psychology , Humans , Pilot Projects , Prevalence , Risk Factors , Tunisia/epidemiology
4.
Med Biol Eng Comput ; 60(5): 1449-1479, 2022 May.
Article in English | MEDLINE | ID: mdl-35304672

ABSTRACT

Aged macular degeneration (AMD) leads to a progressive decline in visual acuity until reaching blindness. It is considered as an irreversible pathology where an early diagnosis remains crucial. However, the lack of ophthalmologists, the permanent increase in elderly people, and their limited mobility involves a delay in AMD diagnosis. In this paper, we propose an automated method for AMD screening. The proposed processing pipeline consists in applying the well-known Radon transform to the macula region in order to model the AMD lesions even with a moderate quality of smartphone-captured fundus images. Thereby, the relevant features are carefully selected, related to the main proprieties of drusens, and then provided to an SVM classifier. The implementation of the method into a smartphone associated to a fundus image capturing device leads to a mobile CAD system that performs higher performance AMD screening. Within this framework and to achieve a real-time implementation, an optimization approach is suggested in order to reduce the processing workload. The evaluation of our method is carried out through the three public STARE, REFUGE, and RFMiD databases. A 4-fold cross-validation approach is used to evaluate the method performance where accuracies of 100%, 95.2%, and 94.3% are respectively obtained with STARE, REFUGE, and RFMiD databases. Comparisons with the state-of-the-art methods in the literature are done. Thereafter, the robustness of the proposed method was evaluated and proved. We note that 100% accuracy was preserved despite the use of degraded quality fundus images as noisy and blurred. Moreover, the propounded method was implemented in S7-Edge and S9 Smartphone devices, where the execution times of 19 and 15 milliseconds were respectively achieved, which proves the AMD real-time detection. Taking advantage of its mobility, cost-effective, detection performance, and reduced execution time, our proposed method seems a good solution for real-time AMD screening on mobile devices.


Subject(s)
Macular Degeneration , Aged , Computers, Handheld , Databases, Factual , Fundus Oculi , Humans , Macular Degeneration/diagnostic imaging , Retina
6.
Clin Imaging ; 76: 6-14, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33545517

ABSTRACT

OBJECTIVE: SARS-CoV-2 is a worldwide health emergency with unrecognized clinical features. This paper aims to review the most recent medical imaging techniques used for the diagnosis of SARS-CoV-2 and their potential contributions to attenuate the pandemic. Recent researches, including artificial intelligence tools, will be described. METHODS: We review the main clinical features of SARS-CoV-2 revealed by different medical imaging techniques. First, we present the clinical findings of each technique. Then, we describe several artificial intelligence approaches introduced for the SARS-CoV-2 diagnosis. RESULTS: CT is the most accurate diagnostic modality of SARS-CoV-2. Additionally, ground-glass opacities and consolidation are the most common signs of SARS-CoV-2 in CT images. However, other findings such as reticular pattern, and crazy paving could be observed. We also found that pleural effusion and pneumothorax features are less common in SARS-CoV-2. According to the literature, the B lines artifacts and pleural line irregularities are the common signs of SARS-CoV-2 in ultrasound images. We have also stated the different studies, focusing on artificial intelligence tools, to evaluate the SARS-CoV-2 severity. We found that most of the reported works based on deep learning focused on the detection of SARS-CoV-2 from medical images while the challenge for the radiologists is how to differentiate between SARS-CoV-2 and other viral infections with the same clinical features. CONCLUSION: The identification of SARS-CoV-2 manifestations on medical images is a key step in radiological workflow for the diagnosis of the virus and could be useful for researchers working on computer-aided diagnosis of pulmonary infections.


Subject(s)
COVID-19 , SARS-CoV-2 , Artificial Intelligence , COVID-19 Testing , Humans , Lung , Tomography, X-Ray Computed
7.
Comput Biol Med ; 118: 103644, 2020 03.
Article in English | MEDLINE | ID: mdl-32174315

ABSTRACT

In the present study, we investigated the velocity profile over the carotid bifurcation in ten healthy volunteers by combining velocity measurements from two imaging modalities (PC-MRI and US-Doppler) and hemodynamic modeling in order to determine the optimal combination for the most realistic velocity estimation. The workflow includes data acquisition, velocity profile extraction at three sites (CCA, ECA and ICA), the arterial geometrical model reconstruction, a mesh generation and a rheological modeling. The results showed that US-Doppler measurements yielded higher velocity values as compared to PC-MRI (about 26% shift in CCA, 52% in ECA and 53% in ICA). This implies higher simulated velocities based on US-Doppler inlet as compared to simulated velocities based on PC-MRI inlet. Overall, PC-MRI inlet based simulations are closer to measurements than US-Doppler inlet based simulations. Moreover, the measured velocities showed that blood flow keeps a parabolic sectional profile distal from CCA, ECA and ICA, while being quite disturbed in the carotid sinus with a significant decrease in magnitude making this site very prone to atherosclerosis.


Subject(s)
Carotid Artery, Common , Hemodynamics , Blood Flow Velocity , Carotid Artery, Common/diagnostic imaging , Humans , Magnetic Resonance Imaging , Ultrasonography
8.
Comput Intell Neurosci ; 2019: 8212867, 2019.
Article in English | MEDLINE | ID: mdl-31065255

ABSTRACT

In this article, we propose to design a new modular architecture for a self-organizing map (SOM) neural network. The proposed approach, called systolic-SOM (SSOM), is based on the use of a generic model inspired by a systolic movement. This model is formed by two levels of nested parallelism of neurons and connections. Thus, this solution provides a distributed set of independent computations between the processing units called neuroprocessors (NPs) which define the SSOM architecture. The NP modules have an innovative architecture compared to those proposed in the literature. Indeed, each NP performs three different tasks without requiring additional external modules. To validate our approach, we evaluate the performance of several SOM network architectures after their integration on an FPGA support. This architecture has achieved a performance almost twice as fast as that obtained in the recent literature.


Subject(s)
Algorithms , Artificial Intelligence , Neural Networks, Computer , Neurons/physiology , Computers , Humans , Image Processing, Computer-Assisted
9.
Biomed Eng Online ; 16(1): 31, 2017 Feb 28.
Article in English | MEDLINE | ID: mdl-28241829

ABSTRACT

BACKGROUND: The sequence of Q, R, and S peaks (QRS) complex detection is a crucial procedure in electrocardiogram (ECG) processing and analysis. We propose a novel approach for QRS complex detection based on the deterministic finite automata with the addition of some constraints. This paper confirms that regular grammar is useful for extracting QRS complexes and interpreting normalized ECG signals. A QRS is assimilated to a pair of adjacent peaks which meet certain criteria of standard deviation and duration. RESULTS: The proposed method was applied on several kinds of ECG signals issued from the standard MIT-BIH arrhythmia database. A total of 48 signals were used. For an input signal, several parameters were determined, such as QRS durations, RR distances, and the peaks' amplitudes. σRR and σQRS parameters were added to quantify the regularity of RR distances and QRS durations, respectively. The sensitivity rate of the suggested method was 99.74% and the specificity rate was 99.86%. Moreover, the sensitivity and the specificity rates variations according to the Signal-to-Noise Ratio were performed. CONCLUSIONS: Regular grammar with the addition of some constraints and deterministic automata proved functional for ECG signals diagnosis. Compared to statistical methods, the use of grammar provides satisfactory and competitive results and indices that are comparable to or even better than those cited in the literature.


Subject(s)
Algorithms , Electrocardiography , Signal Processing, Computer-Assisted , Arrhythmias, Cardiac/diagnosis , Humans , Signal-To-Noise Ratio , Time Factors
10.
Comput Med Imaging Graph ; 48: 49-61, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26748040

ABSTRACT

Accurate coronary artery segmentation is a fundamental step in various medical imaging applications such as stenosis detection, 3D reconstruction and cardiac dynamics assessing. In this paper, a multiscale region growing (MSRG) method for coronary artery segmentation in 2D X-ray angiograms is proposed. First, a region growing rule incorporating both vesselness and direction information in a unique way is introduced. Then an iterative multiscale search based on this criterion is performed. Selected points in each step are considered as seeds for the following step. By combining vesselness and direction information in the growing rule, this method is able to avoid blockage caused by low vesselness values in vascular regions, which in turn, yields continuous vessel tree. Performing the process in a multiscale fashion helps to extract thin and peripheral vessels often missed by other segmentation methods. Quantitative evaluation performed on real angiography images shows that the proposed segmentation method identifies about 80% of the total coronary artery tree in relatively easy images and 70% in challenging cases with a mean precision of 82% and outperforms others segmentation methods in terms of sensitivity. The MSRG segmentation method was also implemented with different enhancement filters and it has been shown that the Frangi filter gives better results. The proposed segmentation method has proven to be tailored for coronary artery segmentation. It keeps an acceptable performance when dealing with challenging situations such as noise, stenosis and poor contrast.


Subject(s)
Coronary Angiography/methods , Coronary Artery Disease/drug therapy , Coronary Vessels/diagnostic imaging , Imaging, Three-Dimensional/methods , Pattern Recognition, Automated/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Algorithms , Humans , Radiographic Image Enhancement/methods , Reproducibility of Results , Sensitivity and Specificity
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