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1.
Nat Commun ; 15(1): 5490, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38944652

ABSTRACT

The widespread administration of COVID-19 vaccines has prompted a need to understand their safety profile. This investigation focuses on the safety of inactivated and mRNA-based COVID-19 vaccines, particularly concerning potential cardiovascular and haematological adverse events. A retrospective cohort study was conducted for 1.3 million individuals residing in Abu Dhabi, United Arab Emirates, who received 1.8 million doses of the inactivated BBIBP CorV (by SinoPharm) and mRNA-based BNT162b2 (Pfizer-BioNTech) vaccines between June 1, 2021, and June 30, 2022. The study's primary outcome was to assess the occurrence of selected cardiovascular and haematological events leading to hospitalization or emergency room visits within 21 days post-vaccination. Results showed no significant increase in the incidence rates of these events compared to the subsequent 22 to 42 days following vaccination. Analysis revealed no elevated risk for adverse outcomes following first (IRR 1·03; 95% CI 0·82-1·31), second (IRR 0·92; 95% CI 0·72-1·16) and third (IRR 0·82; 95% CI 0·66-1·00) doses of either vaccine. This study found no substantial link between receiving either mRNA and inactivated COVID-19 vaccines and a higher likelihood of cardiovascular or haematological events within 21 days after vaccination.


Subject(s)
BNT162 Vaccine , COVID-19 Vaccines , COVID-19 , Cardiovascular Diseases , SARS-CoV-2 , Vaccination , Vaccines, Inactivated , Humans , Retrospective Studies , United Arab Emirates/epidemiology , Male , Female , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , COVID-19 Vaccines/administration & dosage , Middle Aged , Adult , COVID-19/prevention & control , COVID-19/epidemiology , COVID-19/immunology , Cardiovascular Diseases/epidemiology , BNT162 Vaccine/adverse effects , BNT162 Vaccine/immunology , Vaccines, Inactivated/adverse effects , Vaccines, Inactivated/immunology , Vaccines, Inactivated/administration & dosage , SARS-CoV-2/immunology , Vaccination/adverse effects , Aged , Young Adult , Hematologic Diseases/epidemiology , Adolescent
2.
Sensors (Basel) ; 23(18)2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37765894

ABSTRACT

Energy efficiency is important for underwater sensor networks. Designing such networks is challenging due to underwater environmental traits that hinder network lifespan extension. Unlike terrestrial protocols, underwater settings require novel protocols due to slower signal propagation. To enhance energy efficiency in underwater sensor networks, ongoing research concentrates on developing innovative solutions. Thus, in this paper, an intelligent bio-inspired autonomous surveillance system using underwater sensor networks is proposed as an efficient method for data communication. The tunicate swarm algorithm is used for the election of the cluster heads by considering different parameters such as energy, distance, and density. Each layer has several clusters, each of which is led by a cluster head that continuously rotates in response to the fitness values of the SNs using the tunicate swarm algorithm. The performance of the proposed protocol is compared with existing methods such as EE-LHCR, EE-DBR, and DBR, and results show the network's lifespan is improved by the proposed work. Due to the effective fitness parameters during cluster head elections, our suggested protocol may more effectively achieve energy balance, resulting in a longer network lifespan.

3.
Adv Pharm Bull ; 13(3): 446-460, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37646052

ABSTRACT

Nanostructured Lipid Carriers (NLC) are nano-sized colloidal drug delivery system that contains a lipid mixture consisting of both solid and liquid lipids in their core. This Lipid-Based Nanosystem is introduced as a biocompatible, non-toxic, and safe nano-drug delivery system as compared to polymeric or metallic nanoparticles. Due to its safety, stability, and high drug loading capacity compared to other lipid-based nanocarriers, NLC gained the attention of researchers to formulate safe and effective drug carriers. The ability to increase drug solubility and permeability while encapsulating the drug in a lipidic shell makes them an ideal carrier for drug delivery through difficult-to-achieve routes. Surface modification of NLC and the use of various additives result in drug targeting and increased residence time. With such qualities, NLCs can be used to treat a variety of diseases such as cancer, infections, neurodegenerative diseases, hypertension, diabetes, and pain management. This review focuses on the recent developments being made to deliver the drugs and genes through different routes via these nanocarriers. Here, we also discuss about historical background, structure, types of NLC and commonly employed techniques for manufacturing lipid-based nanocarriers.

4.
Comput Intell Neurosci ; 2022: 2140895, 2022.
Article in English | MEDLINE | ID: mdl-36035841

ABSTRACT

In today's real-world, estimation of the level of difficulty of the musical is part of very meaningful musical learning. A musical learner cannot learn without a defined precise estimation. This problem is not very basic but it is complicated up to some extent because of the subjectivity of the contents and the scarcity of the data. In this paper, a lightweight model that generates original music content using deep learning along with generating music based on a specific genre is proposed. The paper discusses a lightweight deep learning-based approach for jazz music generation in MIDI format. In this work, the genre of music chosen is Jazz, and the songs selected are classical numbers composed by various artists. All the songs are in MIDI format and there might be differences in the pace or tone of the music. It is prudential to make sure that the chosen datasets that do not have these kinds of differences and are similar to the final output as desired. A model is trained to take in a part of a music file as input and should produce its continuation. The result generated should be similar to the dataset given as the input. Moreover, the proposed model also generates music using a particular instrument.


Subject(s)
Deep Learning , Music
5.
Nanomaterials (Basel) ; 12(9)2022 May 02.
Article in English | MEDLINE | ID: mdl-35564248

ABSTRACT

A timely replacement of the rather expensive indium-doped tin oxide with aluminum-doped zinc oxide is hindered by the poor uniformity of electronic properties when deposited by magnetron sputtering. Recent results demonstrated the ability to improve the uniformity and to decrease the resistivity of aluminum-doped zinc oxide thin films by decreasing the energy of the oxygen-negative ions assisting in thin film growth by using a tuning electrode. In this context, a comparative study was designed to elucidate if the same phenomenology holds for gallium-doped zinc oxide and indium-doped tin oxide as well. The metal oxide thin films have been deposited in the same setup for similar discharge parameters, and their properties were measured with high spatial resolution and correlated with the erosion track on the target's surface. Furthermore, the films were also subject to post annealing and degradation tests by wet etching. While the tuning electrode was able to reduce the self-bias for all three materials, only the doped zinc oxide films exhibited properties correlating with the erosion track.

6.
J Healthc Eng ; 2022: 9263391, 2022.
Article in English | MEDLINE | ID: mdl-35378945

ABSTRACT

In today's scenario, sepsis is impacting millions of patients in the intensive care unit due to the fact that the mortality rate is increased exponentially and has become a major challenge in the field of healthcare. Such peoples require determinant care which increases the cost of the treatment by using a large number of resources because of the nonavailability of the resources. The treatment of sepsis is available in the early state, but treatment is not started at the right time, and then it converts to the advanced level of sepsis and increases the fatalities. Thus, an intensive analysis is required to detect and identify sepsis at the early stage. There are some models available that work based on the manual score and based on only the biomark features, but these are not fully automated. Some machine learning-based models are also available, which can reduce the mortality rate, but accuracy is not up to date. This paper proposes a machine learning model for early detecting and predicting sepsis in intensive care unit patients. Various models, random forest (RF), linear regression (LR), support vector machine (SVM), naive Bayes (NB), ensemble (of SVM, RF, NB, and LR), XGBoost, and proposed ensemble (of SVM, RF, NB, LR, and XGBoost), are simulated by using the collected data from intensive care unit patient's database that is based on the clinical laboratory values and vital signs. The performance of the models is evaluated by considering the same datasets. The balanced accuracy of RF, LR, SVM, NB, ensemble (of SVM, RF, NB, and LR), XGBoost, and proposed ensemble (of SVM, RF, NB, LR, and XGBoost) is 0.90, 0.73, 0.93, 0.74, 0.94, 0.95, and 0.96, respectively. It is also evident from the experimental results that the proposed ensemble model performs well as compared to the other models.


Subject(s)
Machine Learning , Sepsis , Bayes Theorem , Critical Care , Humans , Intensive Care Units , Sepsis/diagnosis
7.
Comput Intell Neurosci ; 2022: 2206573, 2022.
Article in English | MEDLINE | ID: mdl-35371215

ABSTRACT

In today's environment, electronics technology is growing rapidly because of the availability of the numerous and latest devices which can be deployed for monitoring and controlling the various healthcare systems. Due to the limitations of such devices, there is a dire need to optimize the utilization of the devices. In healthcare systems, Internet of things (IoT) based biosensors networking has minimal energy during transmission and collecting data. This paper proposes an optimized artificial intelligence system using IoT biosensors networking for healthcare problems for efficient data collection from the deployed sensor nodes. Here, an optimized tunicate swarm algorithm is used for optimizing the route for data collection and transmission among the patient and doctor. The fitness function of the optimized tunicate swarm algorithm used the distance, proximity, residual, and average energy of nodes parameters. The proposed method is attributed to the optimal CH chosen under TSA operation having a lower energy consumption. The performance of the proposed method is compared to the existing methods in terms of various metrics like stability period, lifetime, throughput, and clusters per round.


Subject(s)
Biosensing Techniques , Internet of Things , Algorithms , Artificial Intelligence , Delivery of Health Care/methods , Humans
8.
Hum Brain Mapp ; 42(17): 5771-5784, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34487404

ABSTRACT

Population averaged diffusion atlases can be utilized to characterize complex microstructural changes with less bias than data from individual subjects. In this study, a fetal diffusion tensor imaging (DTI) atlas was used to investigate tract-based changes in anisotropy and diffusivity in vivo from 23 to 38 weeks of gestational age (GA). Healthy pregnant volunteers with typically developing fetuses were imaged at 3 T. Acquisition included structural images processed with a super-resolution algorithm and DTI images processed with a motion-tracked slice-to-volume registration algorithm. The DTI from individual subjects were used to generate 16 templates, each specific to a week of GA; this was accomplished by means of a tensor-to-tensor diffeomorphic deformable registration method integrated with kernel regression in age. Deterministic tractography was performed to outline the forceps major, forceps minor, bilateral corticospinal tracts (CST), bilateral inferior fronto-occipital fasciculus (IFOF), bilateral inferior longitudinal fasciculus (ILF), and bilateral uncinate fasciculus (UF). The mean fractional anisotropy (FA) and mean diffusivity (MD) was recorded for all tracts. For a subset of tracts (forceps major, CST, and IFOF) we manually divided the tractograms into anatomy conforming segments to evaluate within-tract changes. We found tract-specific, nonlinear, age related changes in FA and MD. Early in gestation, these trends appear to be dominated by cytoarchitectonic changes in the transient white matter fetal zones while later in gestation, trends conforming to the progression of myelination were observed. We also observed significant (local) heterogeneity in within-tract developmental trajectories for the CST, IFOF, and forceps major.


Subject(s)
Diffusion Tensor Imaging , Fetus/diagnostic imaging , Prenatal Diagnosis , White Matter/diagnostic imaging , Anisotropy , Atlases as Topic , Female , Gestational Age , Humans , Male , Pregnancy
9.
Neuroimage ; 243: 118482, 2021 11.
Article in English | MEDLINE | ID: mdl-34455242

ABSTRACT

Diffusion-weighted magnetic resonance imaging (DW-MRI) of fetal brain is challenged by frequent fetal motion and signal to noise ratio that is much lower than non-fetal imaging. As a result, accurate and robust parameter estimation in fetal DW-MRI remains an open problem. Recently, deep learning techniques have been successfully used for DW-MRI parameter estimation in non-fetal subjects. However, none of those prior works has addressed the fetal brain because obtaining reliable fetal training data is challenging. To address this problem, in this work we propose a novel methodology that utilizes fetal scans as well as scans from prematurely-born infants. High-quality newborn scans are used to estimate accurate maps of the parameter of interest. These parameter maps are then used to generate DW-MRI data that match the measurement scheme and noise distribution that are characteristic of fetal data. In order to demonstrate the effectiveness and reliability of the proposed data generation pipeline, we used the generated data to train a convolutional neural network (CNN) to estimate color fractional anisotropy (CFA). We evaluated the trained CNN on independent sets of fetal data in terms of reconstruction accuracy, precision, and expert assessment of reconstruction quality. Results showed significantly lower reconstruction error (n=100,p<0.001) and higher reconstruction precision (n=20,p<0.001) for the proposed machine learning pipeline compared with standard estimation methods. Expert assessments on 20 fetal test scans showed significantly better overall reconstruction quality (p<0.001) and more accurate reconstruction of 11 regions of interest (p<0.001) with the proposed method.


Subject(s)
Deep Learning , Diffusion Magnetic Resonance Imaging/methods , Fetus/diagnostic imaging , Anisotropy , Gestational Age , Humans , Image Processing, Computer-Assisted/methods , Infant, Newborn , Infant, Premature , Motion , Neural Networks, Computer , Reproducibility of Results , Signal-To-Noise Ratio
10.
Med Image Anal ; 72: 102129, 2021 08.
Article in English | MEDLINE | ID: mdl-34182203

ABSTRACT

Accurate modeling of diffusion-weighted magnetic resonance imaging measurements is necessary for accurate brain connectivity analysis. Existing methods for estimating the number and orientations of fascicles in an imaging voxel either depend on non-convex optimization techniques that are sensitive to initialization and measurement noise, or are prone to predicting spurious fascicles. In this paper, we propose a machine learning-based technique that can accurately estimate the number and orientations of fascicles in a voxel. Our method can be trained with either simulated or real diffusion-weighted imaging data. Our method estimates the angle to the closest fascicle for each direction in a set of discrete directions uniformly spread on the unit sphere. This information is then processed to extract the number and orientations of fascicles in a voxel. On realistic simulated phantom data with known ground truth, our method predicts the number and orientations of crossing fascicles more accurately than several classical and machine learning methods. It also leads to more accurate tractography. On real data, our method is better than or compares favorably with other methods in terms of robustness to measurement down-sampling and also in terms of expert quality assessment of tractography results.


Subject(s)
Diffusion Magnetic Resonance Imaging , Image Processing, Computer-Assisted , Algorithms , Brain/diagnostic imaging , Humans , Machine Learning , Phantoms, Imaging
11.
Environ Dev Sustain ; 23(12): 18252-18277, 2021.
Article in English | MEDLINE | ID: mdl-33897276

ABSTRACT

The present study evaluates the water quality status of 6-km-long Kali River stretch that passes through the Aligarh district in Uttar Pradesh, India, by utilizing high-resolution IRS P6 LISS IV imagery. In situ river water samples collected at 40 random locations were analyzed for seven physicochemical and four heavy metal concentrations, and the water quality index (WQI) was computed for each sampling location. A set of 11 spectral reflectance band combinations were formulated to identify the most significant band combination that is related to the observed WQI at each sampling location. Three approaches, namely multiple linear regression (MLR), backpropagation neural network (BPNN) and gene expression programming (GEP), were employed to relate WQI as a function of most significant band combination. Comparative assessment among the three utilized approaches was performed via quantitative indicators such as R 2, RMSE and MAE. Results revealed that WQI estimates ranged between 203.7 and 262.33 and rated as "very poor" status. Results further indicated that GEP performed better than BPNN and MLR approaches and predicted WQI estimates with high R 2 values (i.e., 0.94 for calibration and 0.91 for validation data), low RMSE and MAE values (i.e., 2.49 and 2.16 for calibration and 4.45 and 3.53 for validation data). Moreover, both GEP and BPNN depicted superiority over MLR approach that yielded WQI with R 2 ~ 0.81 and 0.67 for calibration and validation data, respectively. WQI maps generated from the three approaches corroborate the existing pollution levels along the river stretch. In order to examine the significant differences among WQI estimates from the three approaches, one-way ANOVA test was performed, and the results in terms of F-statistic (F = 0.01) and p-value (p = 0.994 > 0.05) revealed WQI estimates as "not significant," reasoned to the small water sample size (i.e., N = 40). The study therefore recommends GEP as more rational and a better alternative for precise water quality monitoring of surface water bodies by producing simplified mathematical expressions.

13.
Hum Brain Mapp ; 41(12): 3177-3185, 2020 08 15.
Article in English | MEDLINE | ID: mdl-32374063

ABSTRACT

The third trimester of pregnancy is a period of rapid development of fiber bundles in the fetal white matter. Using a recently developed motion-tracked slice-to-volume registration (MT-SVR) method, we aimed to quantify tract-specific developmental changes in apparent diffusion coefficient (ADC), fractional anisotropy (FA), and volume in third trimester healthy fetuses. To this end, we reconstructed diffusion tensor images from motion corrected fetal diffusion magnetic resonance imaging data. With an approved protocol, fetal MRI exams were performed on healthy pregnant women at 3 Tesla and included multiple (2-8) diffusion scans of the fetal head (1-2 b = 0 s/mm2 images and 12 diffusion-sensitized images at b = 500 s/mm2 ). Diffusion data from 32 fetuses (13 females) with median gestational age (GA) of 33 weeks 4 days were processed with MT-SVR and deterministic tractography seeded by regions of interest corresponding to 12 major fiber tracts. Multivariable regression analysis was used to evaluate the association of GA with volume, FA, and ADC for each tract. For all tracts, the volume and FA increased, and the ADC decreased with GA. Associations reached statistical significance for: FA and ADC of the forceps major; volume and ADC for the forceps minor; FA, ADC, and volume for the cingulum; ADC, FA, and volume for the uncinate fasciculi; ADC of the inferior fronto-occipital fasciculi, ADC of the inferior longitudinal fasciculi; and FA and ADC for the corticospinal tracts. These quantitative results demonstrate the complex pattern and rates of tract-specific, GA-related microstructural changes of the developing white matter in human fetal brain.


Subject(s)
Diffusion Tensor Imaging/methods , Fetus/diagnostic imaging , Pregnancy Trimester, Third , Prenatal Diagnosis/methods , White Matter/diagnostic imaging , Female , Fetal Development/physiology , Humans , Male , Neural Pathways/diagnostic imaging , Pregnancy , White Matter/growth & development
14.
J Emerg Med ; 58(1): e1-e3, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31744706

ABSTRACT

BACKGROUND: Naphthalene is widely used in households as an insect repellent, but its poisoning is rare, especially in adults. Naphthalene is a strong oxidant with a pungent smell. CASE REPORT: We report a case of a 16-year-old female who ingested three naphthalene mothballs 3 days prior to admission and presented with history of recurrent vomiting, severe pallor, jaundice, and hemoglobinuria. Investigation found severe hemolytic anemia, indirect hyperbilirubinemia, acute kidney injury, and evidence of intravascular hemolysis. Her urine output was normal throughout the course of illness. She was managed conservatively with i.v. fluid, oral ascorbic acid, and blood transfusion. With treatment our patient improved completely and was discharged in hemodynamically stable condition. She is doing fine after further follow-up. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physician should keep the possibility of poisoning by an oxidizing agent, such as naphthalene, when a patient presents to the emergency department with rapid onset pallor, jaundice, and hemoglobinuria.

15.
Int J Ophthalmol ; 12(5): 774-778, 2019.
Article in English | MEDLINE | ID: mdl-31131235

ABSTRACT

AIM: To do a randomized prospective interventional study for comparing the effects of a single subconjunctival triamcinolone acetonide (SCTA) injection to tapering topical loteprednol in patients undergoing phacoemulsification surgery under topical anesthesia. METHODS: A total of 400 patients were randomized into 2 groups; Group A (200 patients) received 5 mg SCTA at the end of surgery and topical ketorolac tromethamine (0.5%) with ofloxacin (0.3%) combination for 3wk. Group B (200 patients) received tapering topical loteprednol etabonate (0.5%) along with ofloxacin (0.3%) and ketorolac tromethamine (0.5%) for 3wk. Outcomes evaluated were intraocular pressure (IOP), anterior chamber cells/flare and macular oedema postoperatively at 1, 6 and 12wk. RESULTS: Baseline parameters were almost similar in both the groups. No statistical difference was seen between the preoperative and postoperative IOP values for Group A (P=0.82) and Group B (P=0.61) and postoperative IOP values in between both groups (P=0.14) at 1wk. Incidence of cells/flare postoperative was statistically not significant (P=0.82) in both groups at all follow up visits. Postoperative macular oedema was not observed at any follow up visit. CONCLUSION: SCTA appears to be an effective alternative to prolong postoperative topical steroid use.

16.
IEEE Trans Med Imaging ; 38(2): 470-481, 2019 02.
Article in English | MEDLINE | ID: mdl-30138909

ABSTRACT

With an aim to increase the capture range and accelerate the performance of state-of-the-art inter-subject and subject-to-template 3-D rigid registration, we propose deep learning-based methods that are trained to find the 3-D position of arbitrarily-oriented subjects or anatomy in a canonical space based on slices or volumes of medical images. For this, we propose regression convolutional neural networks (CNNs) that learn to predict the angle-axis representation of 3-D rotations and translations using image features. We use and compare mean square error and geodesic loss to train regression CNNs for 3-D pose estimation used in two different scenarios: slice-to-volume registration and volume-to-volume registration. As an exemplary application, we applied the proposed methods to register arbitrarily oriented reconstructed images of fetuses scanned in-utero at a wide gestational age range to a standard atlas space. Our results show that in such registration applications that are amendable to learning, the proposed deep learning methods with geodesic loss minimization achieved 3-D pose estimation with a wide capture range in real-time (<100ms). We also tested the generalization capability of the trained CNNs on an expanded age range and on images of newborn subjects with similar and different MR image contrasts. We trained our models on T2-weighted fetal brain MRI scans and used them to predict the 3-D pose of newborn brains based on T1-weighted MRI scans. We showed that the trained models generalized well for the new domain when we performed image contrast transfer through a conditional generative adversarial network. This indicates that the domain of application of the trained deep regression CNNs can be further expanded to image modalities and contrasts other than those used in training. A combination of our proposed methods with accelerated optimization-based registration algorithms can dramatically enhance the performance of automatic imaging devices and image processing methods of the future.


Subject(s)
Deep Learning , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Algorithms , Brain/diagnostic imaging , Databases, Factual , Female , Fetus/diagnostic imaging , Humans , Infant, Newborn , Pregnancy
17.
Neuroimage ; 185: 593-608, 2019 01 15.
Article in English | MEDLINE | ID: mdl-30172006

ABSTRACT

Altered structural fetal brain development has been linked to neuro-developmental disorders. These structural alterations can be potentially detected in utero using diffusion tensor imaging (DTI). However, acquisition and reconstruction of in utero fetal brain DTI remains challenging. Until now, motion-robust DTI methods have been employed for reconstruction of in utero fetal DTIs. However, due to the unconstrained fetal motion and permissible in utero acquisition times, these methods yielded limited success and have typically resulted in noisy DTIs. Consequently, atlases and methods that could enable groupwise studies, multi-modality imaging, and computer-aided diagnosis from in utero DTIs have not yet been developed. This paper presents the first DTI atlas of the fetal brain computed from in utero diffusion-weighted images. For this purpose an algorithm for computing an unbiased spatiotemporal DTI atlas, which integrates kernel-regression in age with a diffeomorphic tensor-to-tensor registration of motion-corrected and reconstructed individual fetal brain DTIs, was developed. Our new algorithm was applied to a set of 67 fetal DTI scans acquired from healthy fetuses each scanned at a gestational age between 21 and 39 weeks. The neurodevelopmental trends in the fetal brain, characterized by the atlas, were qualitatively and quantitatively compared with the observations reported in prior ex vivo and in utero studies, and with results from imaging gestational-age equivalent preterm infants. Our major findings revealed early presence of limbic fiber bundles, followed by the appearance and maturation of projection pathways (characterized by an age related increase in FA) during late 2nd and early 3rd trimesters. During the 3rd trimester association fiber bundles become evident. In parallel with the appearance and maturation of fiber bundles, from 21 to 39 gestational weeks gradual disappearance of the radial coherence of the telencephalic wall was qualitatively identified. These results and analyses show that our DTI atlas of the fetal brain is useful for reliable detection of major neuronal fiber bundle pathways and for characterization of the fetal brain reorganization that occurs in utero. The atlas can also serve as a useful resource for detection of normal and abnormal fetal brain development in utero.


Subject(s)
Algorithms , Atlases as Topic , Brain/embryology , Fetal Development , Neurogenesis , Diffusion Tensor Imaging , Female , Fetus , Humans , Image Interpretation, Computer-Assisted/methods , Male
18.
Magn Reson Med ; 81(5): 3314-3329, 2019 05.
Article in English | MEDLINE | ID: mdl-30443929

ABSTRACT

PURPOSE: To achieve motion-robust diffusion compartment imaging (DCI) in near continuously moving subjects based on simultaneous multi-slice, diffusion-weighted brain MRI. METHODS: Simultaneous multi-slice (SMS) acquisition enables fast and dense sampling of k- and q-space. We propose to achieve motion-robust DCI via slice-level motion correction by exploiting the rigid coupling between simultaneously acquired slices. This coupling provides 3D coverage of the anatomy that substantially constraints the slice-to-volume alignment problem. This is incorporated into an explicit model of motion dynamics that handles continuous and large subject motion in robust DCI reconstruction. RESULTS: We applied the proposed technique, called Motion Tracking based on Simultanous Multislice Registration (MT-SMR) to multi b-value SMS diffusion-weighted brain MRI of healthy volunteers and motion-corrupted scans of 20 pediatric subjects. Quantitative and qualitative evaluation based on fractional anisotropy in unidirectional fiber regions, and DCI in crossing-fiber regions show robust reconstruction in the presence of motion. CONCLUSION: The proposed approach has the potential to extend routine use of SMS DCI in very challenging populations, such as young children, newborns, and non-cooperative patients.


Subject(s)
Brain/diagnostic imaging , Diffusion Magnetic Resonance Imaging , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Adolescent , Adult , Algorithms , Anisotropy , Child , Child, Preschool , Healthy Volunteers , Humans , Models, Statistical , Motion , Reproducibility of Results
19.
Clin Exp Gastroenterol ; 11: 281-287, 2018.
Article in English | MEDLINE | ID: mdl-30100748

ABSTRACT

OBJECTIVES: This study aimed to determine the change in anatomical location of appendix in full-term pregnancy. STUDY DESIGN: This was a descriptive cross-sectional study. PLACE AND DURATION OF STUDY: Liaquat National University Hospital, Karachi, Pakistan, Department of General Surgery, January 01 to July 31, 2010. PATIENTS AND METHODS: Full-term pregnant women undergoing caesarean section were enrolled. The anatomical position of the appendix was noted by visual inspection with reference to the transtubercular plane (TTP). SPSS-10 was used for analysis. RESULTS: Seventy-seven full-term pregnant female patients who underwent caesarean section were included in the study. Their mean age was 29 years, the mean height was 5.3 feet, and mean gestational age was 38 weeks. Appendix was found at the normal anatomical location in 63 out of 77 patients (81.8%), while it was located above the TTP in 14 patients (18.2%). CONCLUSION: Appendix does not migrate up with increasing gestational age in the majority of pregnant women. In most full-term pregnant female patients, appendix is located at the normal anatomical position.

20.
Med Image Comput Comput Assist Interv ; 11072: 28-35, 2018 Sep.
Article in English | MEDLINE | ID: mdl-32869014

ABSTRACT

Diffusion tensor imaging (DTI) based group analysis has helped uncover the impact of white matter injuries in a wide range of studies involving subjects from preterm neonates to adults. The application of these methods to fetal cohorts, however, has been hampered by the challenging nature of in utero fetal DTI caused by unconstrained fetal motion, limited scan times, and limited signal-to-noise ratio. We present a framework that addresses these issues to systematically evaluate group differences in fetal cohorts. A motion-robust DTI computation approach with a new unbiased DTI template construction method is unified with kernel-regression in age and tensor-specific registration to normalize DTI volumes in an unbiased space. A robust statistical approach is used to map region-specific group differences to the medial representation of the tracts of interest. The proposed approach was applied and showed, for the first time, differences in local white matter fractional anisotropy based on in utero DTI of fetuses with congenital heart disease and age-matched healthy controls. This paper suggests the need for fetal-specific pipelines to be used for DTI-based group analysis involving fetal cohorts.

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