scholarly journals A Prototype Microwave System for 3D Brain Stroke Imaging

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2607 ◽  
Author(s):  
Jorge A. Tobon Vasquez ◽  
Rosa Scapaticci ◽  
Giovanna Turvani ◽  
Gennaro Bellizzi ◽  
David O. Rodriguez-Duarte ◽  
...  
Keyword(s):  
Low Complexity ◽  
3D Images ◽  
Stroke Imaging ◽  
Microwave System ◽  
Imaging Approach ◽  
Minimum Number ◽  
Open Issue ◽  
Brain Stroke ◽  
Differential Imaging

This work focuses on brain stroke imaging via microwave technology. In particular, the open issue of monitoring patients after stroke onset is addressed here in order to provide clinicians with a tool to control the effectiveness of administered therapies during the follow-up period. In this paper, a novel prototype is presented and characterized. The device is based on a low-complexity architecture which makes use of a minimum number of properly positioned and designed antennas placed on a helmet. It exploits a differential imaging approach and provides 3D images of the stroke. Preliminary experiments involving a 3D phantom filled with brain tissue-mimicking liquid confirm the potential of the technology in imaging a spherical target mimicking a stroke of a radius equal to 1.25 cm.

scholarly journals Microwave Imaging for Brain Stroke Monitoring

2020 ◽  
Author(s):  
Jorge A. Tobon Vaquez ◽  
David Rodriguez-Duarte
Keyword(s):  
Low Complexity ◽  
Microwave Imaging ◽  
Invasive Approach ◽  
3D Images ◽  
Non Invasive ◽  
Imaging Approach ◽  
Brain Stroke ◽  
Differential Imaging ◽  
Dielectric Objects

The capability of microwaves to penetrate an object as interact differently with each of its elements, allows Microwave Imaging (MWI) technologies to be used in a myriad of fields and applications to "see-through" an object in a non-invasive approach. For instance, in the biomedical field, the scattered signals from cancer lesions, blood accumulation, and bio-tissues (all considered dielectric objects) contain the information required by imaging of the specific context. In the case of the open medical issue of brain stroke monitoring after onset, MWI provides clinicians with a complementary alternative to the well-establish imaging-based techniques of support of diagnosis and treatment follow-up. An example of a novel low-complexity-architecture MWI prototype with an optimized number of antennas and adequate positioning on a helmet is presented below. It exploits a differential imaging approach and provides 3D images of the stroke. 

scholarly journals Experimental Validation of a Microwave System for Brain Stroke 3-D Imaging

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1232
Author(s):  
David O. Rodriguez-Duarte ◽  
Jorge A. Tobon Vasquez ◽  
Rosa Scapaticci ◽  
Giovanna Turvani ◽  
Marta Cavagnaro ◽  
...  
Keyword(s):  
System Analysis ◽  
Ex Vivo ◽  
Numerical Models ◽  
Low Complexity ◽  
Monopole Antennas ◽  
Microwave System ◽  
Device Validation ◽  
Brain Stroke ◽  
Value Decomposition ◽  
The Brain

This paper experimentally validates the capability of a microwave prototype device to localize hemorrhages and ischemias within the brain as well as proposes an innovative calibration technique based on the measured data. In the reported experiments, a 3-D human-like head phantom is considered, where the brain is represented either with a homogeneous liquid mimicking brain dielectric properties or with ex vivo calf brains. The microwave imaging (MWI) system works at 1 GHz, and it is realized with a low-complexity architecture formed by an array of twenty-four printed monopole antennas. Each antenna is embedded into the “brick” of a semi-flexible dielectric matching medium, and it is positioned conformal to the head upper part. The imaging algorithm exploits a differential approach and provides 3-D images of the brain region. It employs the singular value decomposition of the discretized scattering operator obtained via accurate numerical models. The MWI system analysis shows promising reconstruction results and extends the device validation.

Design and Numerical Characterization of a Low-Complexity Microwave Device for Brain Stroke Monitoring

2018 ◽  
Vol 66 (12) ◽  
pp. 7328-7338 ◽  
Author(s):  
Rosa Scapaticci ◽  
Jorge Tobon ◽  
Gennaro Bellizzi ◽  
Francesca Vipiana ◽  
Lorenzo Crocco
Keyword(s):  
Low Complexity ◽  
Microwave Device ◽  
Numerical Characterization ◽  
Brain Stroke

scholarly journals Effects of a steps/day programme with evaluation in physical education on body mass index in schoolchildren 11-12 years of age

Kinesiology ◽  
2016 ◽  
Vol 48 (1) ◽  
pp. 132-141 ◽  
Author(s):  
Alberto Grao-Cruces ◽  
Rafael Ruiz-López ◽  
José-Enrique Moral-García ◽  
Alberto Ruiz-Ariza ◽  
Emilio J. Martínez-López
Keyword(s):  
Physical Activity ◽  
Body Mass Index ◽  
Physical Education ◽  
Body Mass ◽  
Controlled Trial ◽  
Control Group ◽  
Education Students ◽  
Minimum Number ◽  
Experimental Group

The aim of the study was to assess the effects that a steps/day programme may have on body mass index (BMI) among primary education students (11.37±0.48 years). A six-week controlled trial with a follow-up was completed with an experimental group (N=66, pedometer + steps/day programme + reinforcement programme in their physical education (PE) marks + weekly follow-up in PE), and a control group (N=76). Omron HJ-152-E2 pedometers were used. Normoweight students complied with programme requirements to a greater extent than their overweight counterparts (72.7 vs 59.1%). The programmed minimum number of 12,000 steps/day for boys and 10,000 for girls was exceeded by 83% of boys and 60% of girls. The differences in the number of steps/day between boys (14,274) and girls (10,626) were significant across all the measured periods (p<.05). The results show that the teenagers who complied with the programme requirements reduced their BMI significantly after the intervention (p<.001) and this reduction persisted for six weeks after the programme (p<.001). In conclusion, the six-week programme of 12,000 steps/day for boys and 10,000 for girls, jointly with a reinforcement programme in their PE marks and weekly follow-up by their PE teacher, reduces BMI significantly in 11-12-year-old schoolchildren. Monitored steps/day programmes in the PE curriculum increase out-of-school physical activity and reduce BMI in 11-12-year-old schoolchildren.

scholarly journals Corticospinal Tract Injury Estimated From Acute Stroke Imaging Predicts Upper Extremity Motor Recovery After Stroke

Stroke ◽  
2019 ◽  
Vol 50 (12) ◽  
pp. 3569-3577 ◽  
Author(s):  
David J. Lin ◽  
Alison M. Cloutier ◽  
Kimberly S. Erler ◽  
Jessica M. Cassidy ◽  
Samuel B. Snider ◽  
...  
Keyword(s):  
Acute Stroke ◽  
Upper Extremity ◽  
Corticospinal Tract ◽  
Area Under The Curve ◽  
Standard Of Care ◽  
Major Effect ◽  
Motor Recovery ◽  
Stroke Imaging ◽  
Recovery Potential

Background and Purpose— Injury to the corticospinal tract (CST) has been shown to have a major effect on upper extremity motor recovery after stroke. This study aimed to examine how well CST injury, measured from neuroimaging acquired during the acute stroke workup, predicts upper extremity motor recovery. Methods— Patients with upper extremity weakness after ischemic stroke were assessed using the upper extremity Fugl-Meyer during the acute stroke hospitalization and again at 3-month follow-up. CST injury was quantified and compared, using 4 different methods, from images obtained as part of the stroke standard-of-care workup. Logistic and linear regression were performed using CST injury to predict ΔFugl-Meyer. Injury to primary motor and premotor cortices were included as potential modifiers of the effect of CST injury on recovery. Results— N=48 patients were enrolled 4.2±2.7 days poststroke and completed 3-month follow-up (median 90-day modified Rankin Scale score, 3; interquartile range, 1.5). CST injury distinguished patients who reached their recovery potential (as predicted from initial impairment) from those who did not, with area under the curve values ranging from 0.70 to 0.8. In addition, CST injury explained ≈20% of the variance in the magnitude of upper extremity recovery, even after controlling for the severity of initial impairment. Results were consistent when comparing 4 different methods of measuring CST injury. Extent of injury to primary motor and premotor cortices did not significantly influence the predictive value that CST injury had for recovery. Conclusions— Structural injury to the CST, as estimated from standard-of-care imaging available during the acute stroke hospitalization, is a robust way to distinguish patients who achieve their predicted recovery potential and explains a significant amount of the variance in poststroke upper extremity motor recovery.

scholarly journals Endovascular Internal Trapping by Low-Concentration N-butyl-2-Cyanoacrylate for a Ruptured Giant Common Carotid Artery Pseudoaneurysm

2020 ◽  
Vol 55 (1) ◽  
pp. 81-85
Author(s):  
Tomoaki Harada ◽  
Atsushi Fujita ◽  
Junichi Sakata ◽  
Masaaki Kohta ◽  
Eiji Kohmura
Keyword(s):  
Carotid Artery ◽  
Common Carotid Artery ◽  
Parent Artery ◽  
Artery Pseudoaneurysm ◽  
Low Concentration ◽  
Complete Obliteration ◽  
Minimum Number ◽  
History Of ◽  
Giant Pseudoaneurysm

Treating carotid blowout syndrome following rupture of giant pseudoaneurysms is difficult because the destroyed parent artery precludes conventional treatment. We present a patient with a ruptured giant pseudoaneurysm that we occluded using a modified internal trapping technique with low-concentration N-butyl-2-cyanoacrylate (NBCA) and a minimum number of coils. An 80-year-old man with a history of chemoradiation therapy for oropharyngeal cancer presented with several episodes of active bleeding from the subsequent tracheostomy site. Radiological examination revealed a giant right common carotid artery (CCA) pseudoaneurysm. Endovascular internal trapping was performed using both NBCA and coils under proximal flow control. We slowly injected 9 ml of low-concentration NBCA, which subsequently filled the entire pseudoaneurysm. We then injected an additional 2 ml of NBCA into the proximal CCA to achieve complete obliteration. No re-bleeding was observed during the 6-month follow-up. Endovascular internal trapping using low-concentration NBCA was feasible to treat a giant CCA pseudoaneurysm. The injected low-concentration NBCA filled the entire pseudoaneurysm without the risk of catheter entrapment.

REDUCING RESOURCE UNCERTAINTY USING SEISMIC AMPLITUDE ANALYSIS ON THE SOUTHERN RANKIN TREND, NORTHWEST AUSTRALIA

1999 ◽  
Vol 39 (1) ◽  
pp. 128 ◽  
Author(s):  
D. Sibley ◽  
F. Herkenhoff ◽  
D. Criddle ◽  
M. McLerie
Keyword(s):  
Seismic Attributes ◽  
3D Seismic ◽  
Amplitude Analysis ◽  
Seismic Amplitude ◽  
Amplitude Versus Offset ◽  
Minimum Number ◽  
Gas Fields ◽  
Resource Uncertainty

Between 1973 and 1996 West Australian Petroleum Pty Limited (WAPET) discovered five major gas fields on the southern Rankin Trend including Spar, West Tryal Rocks, Gorgon, Chrysaor, and Dionysus (collectively termed the Greater Gorgon Resource). Recent discoveries at Chrysaor and Dionysus emphasise the role of subtle 3D seismic attributes in finding hydrocarbons and defining reserves with a minimum number of wells.The Gorgon, Chrysaor, and Dionysus fields were covered by 3D seismic data shot in 1991 and 1995, which led WAPET to discover Chrysaor and later Dionysus. Subsequent to the 3D acquisitions, field reservoirs have been correlated with anomalous seismic events (seismic amplitude and amplitude versus offset) that conform to depth structure. Follow-up work has shown that combining these 3D seismic attributes improves the prediction of wet sands, gas sands, and other lithologies.The resulting understanding and confidence provided by this 3D seismic has driven an aggressive exploration program and defined field reserves at a high confidence level. Results include the recent award of permit area WA-267-P to WAPET and the ongoing studies to begin development of the Greater Gorgon Resource.

scholarly journals Optimized Flat-Detector CT in Stroke Imaging: Ready for First-Line Use?

2016 ◽  
Vol 43 (1-2) ◽  
pp. 9-16 ◽  
Author(s):  
Matthias Eckert ◽  
Philipp Gölitz ◽  
Hannes Lücking ◽  
Tobias Struffert ◽  
Frauke Knossalla ◽  
...  
Keyword(s):  
Imaging Modality ◽  
High Sensitivity ◽  
Reconstruction Algorithm ◽  
Clinical Findings ◽  
Rater Agreement ◽  
Flat Detector ◽  
Stroke Imaging ◽  
Imaging Approach ◽  
Ischemic Attack ◽  
Subarachnoid Hemorrhages

Background: Using flat-detector CT (FD-CT) for stroke imaging has the advantage that both diagnostic imaging and endovascular therapy can be performed directly within the Angio Suite without any patient transfer and time delay. Thus, stroke management could be speeded up significantly, and patient outcome might be improved. But as precondition for using FD-CT as primary imaging modality, a reliable exclusion of intracranial hemorrhage (ICH) has to be possible. This study aimed to investigate whether optimized native FD-CT, using a newly implemented reconstruction algorithm, may reliably detect ICH in stroke patients. Additionally, the potential to identify ischemic changes was evaluated. Methods: Cranial FD-CT scans were obtained in 102 patients presenting with acute ischemic stroke (n = 32), ICH (n = 45) or transient ischemic attack (n = 25). All scans were reconstructed with a newly implemented half-scan cone-beam algorithm. Two experienced neuroradiologists, unaware of clinical findings, evaluated independently the FD-CTs screening for hemorrhage or ischemic signs. The findings were correlated to CT, and rater and inter-rater agreement was assessed. Results: FD-CT demonstrated high sensitivity (95-100%) and specificity (100%) in detecting intracerebral and intraventricular hemorrhage (IVH). Overall, interobserver agreement (κ = 0.92) was almost perfect and rater agreement to CT highly significant (r = 0.81). One infratentorial ICH and 10 or 11 of 22 subarachnoid hemorrhages (SAHs) were missed of whom 7 were perimesencephalic. The sensitivity for detecting acute ischemic signs was poor in blinded readings (0 or 25%, respectively). Conclusions: Optimized FD-CT, using a newly implemented reconstruction algorithm, turned out as a reliable tool for detecting supratentorial ICH and IVH. However, detection of infratentorial ICH and perimesencephalic SAH is limited. The potential of FD-CT in detecting ischemic changes is poor in blinded readings. Thus, plain FD-CT seems insufficient as a standalone modality in acute stroke, but within a multimodal imaging approach primarily using the FD technology, native FD-CT seems capable to exclude reliably supratentorial hemorrhage. Currently, FD-CT imaging seems not yet ready for wide adoption, replacing regular CT, and should be reserved for selected patients. Furthermore, prospective evaluations are necessary to validate this approach in the clinical setting.

Sign in / Sign up

Export Citation Format

Share Document