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Globaly imaging for lower back pain has increased over the last decades, especially the use of MRI. This trend is true for Sweden as well. A previous study by Wnuk et. al. found that 13% percent of outpatient MRI´s of the lower back had actionable findings. With a rather high rate of false positive findings. The rate of actionable findings in a Swedish context is unkown thus we intend to replicate the study done by Wnuk et al. but in a Swedish setting. Methods This study is a retrospective cohort study of lumbar spine MR imaging. The study is descriptive in nature. Simple descriptive statistics will be used to summarize data. Two reviewers will independently go through radiological reports and patient journals manually to note findings and whether they led to a change of treatment or new diagnoses. In the case of disagreement a third senior reviewer will be used to settle the case. Independent manual assessment will be used instead of automatic text search engine in order to mitigate risk of over or under-assessing any of the study endpoints. The outcomes of the study are "actionable exams", "potentially harmful findings" and appropiateness as descriped below. Actionable exams: Examinations will be classified as either “actionable,” or “non-actionable” using the definitions created by Wnuk et. al. An examination could satisfy more than one set of criteria but would contribute only once to the overall total of actionable examinations. An actionable examination is one which either: 1. Contributes to planning of an anatomically specific treatment; 2. Contributes to a new diagnosis of fracture, cancer or infection; 3. Is performed to follow known lumbar spine pathology (other than degenerative conditions). Examinations that do not meet any of the three criteria are classified as non-actionable. Anatomically specific treatment: An examination is classified as actionable if a spine procedure occurred within 12 months following the examination, without an intervening lumbar spine MRI, for which the anatomical imaging information might be used in planning. Procedures considered included laminectomy, foraminotomy, resection, drainage, decompression, discectomy, vertebral fusion, vertebroplasty and radiation therapy performed at spinal levels from T12 through S1, inclusive. Furthermore we will also note less invasive treatments (nerve root block, facet joint injection,) and of more doubtful efficacy. They will be presented in aggregate and separate. Contribution to a new diagnosis: New diagnoses of cancer, infection, acute fracture of the spine or other clinically significant disease requiring treatment. For all positive reports, clinical notes will be examined up to one year following the examination. A finding will be considered a “true positive” if confirmed by subsequent imaging, blood tests or biopsy, or if treatment was initiated based on the imaging findings. Treatment might include surgery, chemotherapy or radiation therapy for cancer, and treatment with antibiotics or drainage for infection. A finding will also considered a true positive if accepted as real by the clinician as indicated in the clinical chart. False positives (see below) were considered as harmful. Following a known condition: Examinations are classified as actionable if they are used to follow known condition (other than degenerative disease). Potentially harmful: When the suggestion of cancer or infection raised in the report is not substantiated by subsequent events the finding was considered a “false positive,” and the examination is classified as potentially harmful since it may lead to further evaluations, incorrect treatment and/or patient anxiety. Appropriateness: While not formally used in our setting we asses this in a smaller random sample in order to benchmark our referrals to the findings in the previous study by Wnuk et al. Appropriateness scores, based on ACR criteria, from 1-9 will be assessed based on information given in the referrals. Study population: Outpatient adult lumbar spine MRI performed in Skane county between 20220101 and 20230101. Imaging protocols vary to some extent but generally include sagittal T1 and T2 weighted images covering the lower thoracic spine through the sacrum. Usually there is also a coronal T2 TIRM sequence covering the whole abdomen and pelvis. Exams were performed on either 1.5 or 3.0 Tesla and interpreted by radiologists of varying training and subspecialty, some by musculoskeletal radiologists or neuroradiologists. Exams were read at non-academic institutions. Demographic information, indications for the study, and appropriateness scores will be obtained from the radiology information system(PACS). Examinations will be excluded if they were incomplete or if the patient is younger than 18 years of age.

The primary aim of this study, is to assess whether ADC-based intensity weighted lesion volume is more associated with functional outcome than total lesion volume alone in post-EVT anterior circulation LVO stroke patients. The secondary aim is to investigate whether other ADC intensity based biomarkers (infarct density and mean intensity) are more associated with functional outcome than total lesion volume alone. Lastly, we will investigate the influence of intravenous alteplase before EVT on weighted lesion volume, infarct density and mean ADC. Research questions 1. Does ADC-based intensity weighted lesion volume provide additional information on functional outcomes beyond total lesion volume in anterior circulation LVO stroke patients? 2. Do previously established ADC-based biomarkers (infarct density and mean intensity) provide additional information on functional outcome beyond total lesion volume in anterior circulation LVO stroke patients? 3. How do infarct density, weighted lesion volume and total lesion volume differ between patients who received EVT alone and those who received both EVT and intravenous alteplase?

The primary aim of this study, is to assess whether ADC-based intensity weighted lesion volume is more associated with functional outcome than total lesion volume alone in post-EVT anterior circulation LVO stroke patients. The secondary aim is to investigate whether other ADC intensity based biomarkers (infarct density and mean intensity) are more associated with functional outcome than total lesion volume alone. Lastly, we will investigate the influence of intravenous alteplase before EVT on weighted lesion volume, infarct density and mean ADC. Research questions 1. Does ADC-based intensity weighted lesion volume provide additional information on functional outcomes beyond total lesion volume in anterior circulation LVO stroke patients? 2. Do previously established ADC-based biomarkers (infarct density and mean intensity) provide additional information on functional outcome beyond total lesion volume in anterior circulation LVO stroke patients? 3. How do infarct density, weighted lesion volume and total lesion volume differ between patients who received EVT alone and those who received both EVT and intravenous alteplase?

The primary aim of this study, is to assess whether ADC-based intensity weighted lesion volume is more associated with functional outcome than total lesion volume alone in post-EVT anterior circulation LVO stroke patients. The secondary aim is to investigate whether other ADC intensity based biomarkers (infarct density and mean intensity) are more associated with functional outcome than total lesion volume alone. Lastly, we will investigate the influence of intravenous alteplase before EVT on weighted lesion volume, infarct density and mean ADC. Research questions 1. Does ADC-based intensity weighted lesion volume provide additional information on functional outcomes beyond total lesion volume in anterior circulation LVO stroke patients? 2. Do previously established ADC-based biomarkers (infarct density and mean intensity) provide additional information on functional outcome beyond total lesion volume in anterior circulation LVO stroke patients? 3. How do infarct density, weighted lesion volume and total lesion volume differ between patients who received EVT alone and those who received both EVT and intravenous alteplase?

The primary aim of this study, is to assess whether ADC-based intensity weighted lesion volume is more associated with functional outcome than total lesion volume alone in post-EVT anterior circulation LVO stroke patients. The secondary aim is to investigate whether other ADC intensity based biomarkers (infarct density and mean intensity) are more associated with functional outcome than total lesion volume alone. Lastly, we will investigate the influence of intravenous alteplase before EVT on weighted lesion volume, infarct density and mean ADC. Research questions 1. Does ADC-based intensity weighted lesion volume provide additional information on functional outcomes beyond total lesion volume in anterior circulation LVO stroke patients? 2. Do previously established ADC-based biomarkers (infarct density and mean intensity) provide additional information on functional outcome beyond total lesion volume in anterior circulation LVO stroke patients? 3. How do infarct density, weighted lesion volume and total lesion volume differ between patients who received EVT alone and those who received both EVT and intravenous alteplase?

The primary aim of this study, is to assess whether ADC-based intensity weighted lesion volume is more associated with functional outcome than total lesion volume alone in post-EVT anterior circulation LVO stroke patients. The secondary aim is to investigate whether other ADC intensity based biomarkers (infarct density and mean intensity) are more associated with functional outcome than total lesion volume alone. Lastly, we will investigate the influence of intravenous alteplase before EVT on weighted lesion volume, infarct density and mean ADC. Research questions 1. Does ADC-based intensity weighted lesion volume provide additional information on functional outcomes beyond total lesion volume in anterior circulation LVO stroke patients? 2. Do previously established ADC-based biomarkers (infarct density and mean intensity) provide additional information on functional outcome beyond total lesion volume in anterior circulation LVO stroke patients? 3. How do infarct density, weighted lesion volume and total lesion volume differ between patients who received EVT alone and those who received both EVT and intravenous alteplase?

Magnetic resonance imaging (MRI), a non-invasive radiographic test, is used toaid the diagnosis of diseases and abnormalities. It requires a cooperative and immobilepatient for approximately 30-90 minutes (Tobin, Spurrier, and Wetzel, 1992).Immobilizing a child for this length of time is a challenge. History has shown that mostyoung children are unable to remain motionless for the extended length of time necessaryto perform a MRI examination without sedation (Bisset and Ball, 1991). Providing thesedation is the responsibility of the anesthesia provider. Sedation of the pediatric patient is a process carefully planned by the anesthesiaprovider. Achieving cooperation and immobility of the patient are the main concerns forthe radiologist while performing the MRI scan. Any sudden movements by the pediatricpatient can result in an inconclusive scan. Hubbard, Markowitz, Kimmel, Kroger, andBartko (1992) demonstrated that the failure of sedation to enable completion of anexamination is more frequent with MRI scan than with other imaging modalities. Astudy by Slovis and associates (1993) concluded that after repeated failed MRI scans, it is advisable to use the most effective drug regimen with the fewest side effects to providesedation for pediatric patients. The problem for the anesthesia provider is developing asedation regimen that renders immobility of the pediatric patient without compromisingtheir respiratory or hemodynamic status. At a midwest medical facility near Dayton,Ohio, such a regimen has been developed and implemented.

The Edge, appropriate for exploring contemporary military operations raises issues regarding comparative performance to traditional hierarchal configurations. Well-controlled experimental design offers insight about the internal workings of the Edge organization with high levels of reliability and internal validity. Leweling and Nissen (2007) reported results of an extension to a series of laboratory experiments using the ELICIT multiplayer intelligence game. This confirmed that Edge organizations outperform Hierarchy organizations in certain tasks, environmental contexts, and performance measures. Their findings answer questions and inform future experimentation. In particular, complementary research suggests that participants' tacit knowledge and contextual influence modulates those results. If so, then understanding tacit knowledge and contextual influence at the physiological level-and linking such understanding to individual and team performance- can reveal novel insight into how to organize, lead and perform in high-capability organizations (Kalbfleisch et al., 2006, 2007, Roberts et al., 2009, Kalbfleisch, in press). In this paper we explain the elements necessary to understand and employ during state-of-the-art functional magnetic resonance imaging (fMRI) to illuminate such physiological bases. Specifically, neuroimaging can be used to identify neural systems affiliated with behavior during meaningful moments of exchange to characterize tacit knowledge during ELICIT. Building upon previous work, this research extends the state of the art and opens new avenues for continued knowledge development.

In this study, imaging of electrical current density in conducting objects, which contain nuclear magnetic resonance (NMR) active nuclei is planned using 0.15T Magnetic Resonance Imaging (MRI) system. Current to be imaged is externally applied to the object in synchrony with a standard spin-echo pulse sequence. Applied current is a bipolar DC current pulse, which creates a DC current density at each cycle within the object. The applied current pulse creates a measurable magnetic flux density. The component of magnetic flux density parallel to the main magnetic field accumulates an additional phase in the phase of the complex MR image. Magnetic flux density can be extracted using two phase images acquired with and without the current pulse. Measurement of all three components of magnetic flux density makes the reconstruction of current density possible with a spatial resolution equal to the half of the MR resolution. Experiments performed on several phantoms and the results are presented.

In this study, imaging of electrical current density in conducting objects, which contain nuclear magnetic resonance (NMR) active nuclei is planned using 0.15T Magnetic Resonance Imaging (MRI) system. Current to be imaged is externally applied to the object in synchrony with a standard spin-echo pulse sequence. Applied current is a bipolar DC current pulse, which creates a DC current density at each cycle within the object. The applied current pulse creates a measurable magnetic flux density. The component of magnetic flux density parallel to the main magnetic field accumulates an additional phase in the phase of the complex MR image. Magnetic flux density can be extracted using two phase images acquired with and without the current pulse. Measurement of all three components of magnetic flux density makes the reconstruction of current density possible with a spatial resolution equal to the half of the MR resolution. Experiments performed on several phantoms and the results are presented.

This article is from PLoS ONE , volume 9 . Abstract Background: Previous studies demonstrated that primary open angle glaucoma (POAG) is associated with abnormal brain structure; however, little is known about the changes in the local synchronization of spontaneous activity. The main objective of this study was to investigate spontaneous brain activity in patients with POAG using regional homogeneity (ReHo) analysis based on resting state functional magnetic resonance imaging (rs-fMRI). Methodology/Principal Findings: Thirty-nine POAG patients and forty-one age- and gender- matched healthy controls were finally included in the study. ReHo values were used to evaluate spontaneous brain activity and whole brain voxel-wise analysis of ReHo was carried out to detect differences by region in spontaneous brain activity between groups. Compared to controls, POAG patients showed increased ReHo in the right dorsal anterior cingulated cortex, the bilateral medial frontal gyrus and the right cerebellar anterior lobe, and decreased ReHo in the bilateral calcarine, bilateral precuneus gryus, bilateral pre/postcentral gyrus, left inferior parietal lobule and left cerebellum posterior lobe. A multiple linear regression analysis was performed to explore the relationships between clinical measures and ReHo by region showed significant group differences in the POAG group. Negative correlations were found between age and the ReHo values of the superior frontal gyrus (r = −0.323, p = 0.045), left calcarine (r = −0.357, p = 0.026) and inferior parietal lobule (r = −0.362, p = 0.024). A negative correlation was found between the ReHo values of the left precuneus and the cumulative mean defect (r = −0.400, p = 0.012). Conclusions: POAG was associated with abnormal brain spontaneous activity in some brain regions and such changed regional activity may be associated with clinical parameters. Spontaneous brain activity may play a role in POAG initiation and progression.

This article is from PLoS ONE , volume 9 . Abstract Chronic neuropathic pain following surgery represents a serious worldwide health problem leading to life-long treatment and the possibility of significant disability. In this study, neuropathic pain was modeled using the chronic constriction injury (CCI). The CCI rats exhibit mechanical hypersensitivity (typical neuropathic pain symptom) to mechanical stimulation of the affected paw 11 days post surgery, at a time when sham surgery animals do not exhibit hypersensitivity. Following a similar time course, TRPV1 gene expression appears to rise with the hypersensitivity to mechanical stimulation. Recent studies have shown that immune cells play a role in the development of neuropathic pain. To further explore the relationship between neuropathic pain and immune cells, we hypothesize that the infiltration of immune cells into the affected sciatic nerve can be monitored in vivo by molecular imaging. To test this hypothesis, an intravenous injection of a novel perfluorocarbon (PFC) nanoemulsion, which is phagocytosed by inflammatory cells (e.g. monocytes and macrophages), was used in a rat CCI model. The nanoemulsion carries two distinct imaging agents, a near-infrared (NIR) lipophilic fluorescence reporter (DiR) and a 19F MRI (magnetic resonance imaging) tracer, PFC. We demonstrate that in live rats, NIR fluorescence is concentrated in the area of the affected sciatic nerve. Furthermore, the 19F MRI signal was observed on the sciatic nerve. Histological examination of the CCI sciatic nerve reveals significant infiltration of CD68 positive macrophages. These results demonstrate that the infiltration of immune cells into the sciatic nerve can be visualized in live animals using these methods.

This article is from Breast Cancer Research : BCR , volume 15 . Abstract None

This article is from Journal of Cardiovascular Magnetic Resonance , volume 16 . Abstract None

This article is from Journal of Cardiovascular Magnetic Resonance , volume 16 . Abstract None

This article is from Journal of Cardiovascular Magnetic Resonance , volume 16 . Abstract None

This article is from Cerebrovascular Diseases Extra , volume 4 . Abstract Background: The type of neuroimaging for the evaluation of transient ischemic attack (TIA) is debatable. Many patients undergo head computed tomography (CT) with or without CT angiogram (CTA) while being at the emergency department (ED) and later magnetic resonance imaging (MRI) with MR angiogram (MRA) during admission. We hypothesized that evaluation with only one imaging modality (CT/CTA or MRI/MRA) is sufficient to formulate a treatment plan. We looked for the most cost-effective way to evaluate TIA patients. Methods: We performed a retrospective chart review of 82 patients with TIA. All patients had completely resolved neurological deficit at the time of their evaluation in the ED. We divided the patients into two groups. In group 1, the evaluation included CT with CTA of the head and neck. In group 2, the evaluation included brain MRI with MRA or CTA of the head and neck. We compared these two groups for clinical characteristics and etiological evaluations of stroke/TIA. The outcomes were measured by the number of therapeutic adjustments for the prevention of another ischemic stroke/TIA at the time of discharge from the hospital and revascularization procedures. We counted the following as therapeutic adjustment: (1) antiplatelet therapy was started de novo; (2) anticoagulation was started; (3) arterial revascularization procedure was performed, and (4) one antiplatelet agent was substituted for another. We performed a cost-effectiveness analysis if the outcomes of the two groups were different and a cost-minimization analysis if there was no difference in the outcomes. All cost calculations were made based on Medicare CPT codes. Results: Group 1 included 23 patients and group 2 59 patients. The patients in both groups had similar demographic and clinical characteristics. There was no difference in other etiological evaluations in groups 1 and 2. All patients underwent head CT as the first tool of evaluation whether MRI was done later or not. Therapeutic adjustments and revascularization procedures did not differ between the two groups. All head CTs showed no acute changes. MRI showed small ischemic infarcts in 44% of the patients in group 2. The average per-patient cost of neuroimaging with CT/CTA was USD 1,460.00, with CT and MRI/MRA USD 1,569 and with CT/CTA and brain MRI USD 2,090.00 (p < 0.01). Conclusion: Either MRI/MRA or CT/CTA might be sufficient for the evaluation of patients with TIA or small asymptomatic strokes. If head CT at the ED is bypassed, a brain MRI with MRA of the head and neck would be the most informative tool at the lowest cost. Prospective studies with larger numbers of patients are needed for a better understanding of the safety and cost of imaging tools used for patients with TIA.

This article is from Cerebrovascular Diseases Extra , volume 4 . Abstract Background: The type of neuroimaging for the evaluation of transient ischemic attack (TIA) is debatable. Many patients undergo head computed tomography (CT) with or without CT angiogram (CTA) while being at the emergency department (ED) and later magnetic resonance imaging (MRI) with MR angiogram (MRA) during admission. We hypothesized that evaluation with only one imaging modality (CT/CTA or MRI/MRA) is sufficient to formulate a treatment plan. We looked for the most cost-effective way to evaluate TIA patients. Methods: We performed a retrospective chart review of 82 patients with TIA. All patients had completely resolved neurological deficit at the time of their evaluation in the ED. We divided the patients into two groups. In group 1, the evaluation included CT with CTA of the head and neck. In group 2, the evaluation included brain MRI with MRA or CTA of the head and neck. We compared these two groups for clinical characteristics and etiological evaluations of stroke/TIA. The outcomes were measured by the number of therapeutic adjustments for the prevention of another ischemic stroke/TIA at the time of discharge from the hospital and revascularization procedures. We counted the following as therapeutic adjustment: (1) antiplatelet therapy was started de novo; (2) anticoagulation was started; (3) arterial revascularization procedure was performed, and (4) one antiplatelet agent was substituted for another. We performed a cost-effectiveness analysis if the outcomes of the two groups were different and a cost-minimization analysis if there was no difference in the outcomes. All cost calculations were made based on Medicare CPT codes. Results: Group 1 included 23 patients and group 2 59 patients. The patients in both groups had similar demographic and clinical characteristics. There was no difference in other etiological evaluations in groups 1 and 2. All patients underwent head CT as the first tool of evaluation whether MRI was done later or not. Therapeutic adjustments and revascularization procedures did not differ between the two groups. All head CTs showed no acute changes. MRI showed small ischemic infarcts in 44% of the patients in group 2. The average per-patient cost of neuroimaging with CT/CTA was USD 1,460.00, with CT and MRI/MRA USD 1,569 and with CT/CTA and brain MRI USD 2,090.00 (p < 0.01). Conclusion: Either MRI/MRA or CT/CTA might be sufficient for the evaluation of patients with TIA or small asymptomatic strokes. If head CT at the ED is bypassed, a brain MRI with MRA of the head and neck would be the most informative tool at the lowest cost. Prospective studies with larger numbers of patients are needed for a better understanding of the safety and cost of imaging tools used for patients with TIA.

This article is from Cerebrovascular Diseases Extra , volume 4 . Abstract Background: The type of neuroimaging for the evaluation of transient ischemic attack (TIA) is debatable. Many patients undergo head computed tomography (CT) with or without CT angiogram (CTA) while being at the emergency department (ED) and later magnetic resonance imaging (MRI) with MR angiogram (MRA) during admission. We hypothesized that evaluation with only one imaging modality (CT/CTA or MRI/MRA) is sufficient to formulate a treatment plan. We looked for the most cost-effective way to evaluate TIA patients. Methods: We performed a retrospective chart review of 82 patients with TIA. All patients had completely resolved neurological deficit at the time of their evaluation in the ED. We divided the patients into two groups. In group 1, the evaluation included CT with CTA of the head and neck. In group 2, the evaluation included brain MRI with MRA or CTA of the head and neck. We compared these two groups for clinical characteristics and etiological evaluations of stroke/TIA. The outcomes were measured by the number of therapeutic adjustments for the prevention of another ischemic stroke/TIA at the time of discharge from the hospital and revascularization procedures. We counted the following as therapeutic adjustment: (1) antiplatelet therapy was started de novo; (2) anticoagulation was started; (3) arterial revascularization procedure was performed, and (4) one antiplatelet agent was substituted for another. We performed a cost-effectiveness analysis if the outcomes of the two groups were different and a cost-minimization analysis if there was no difference in the outcomes. All cost calculations were made based on Medicare CPT codes. Results: Group 1 included 23 patients and group 2 59 patients. The patients in both groups had similar demographic and clinical characteristics. There was no difference in other etiological evaluations in groups 1 and 2. All patients underwent head CT as the first tool of evaluation whether MRI was done later or not. Therapeutic adjustments and revascularization procedures did not differ between the two groups. All head CTs showed no acute changes. MRI showed small ischemic infarcts in 44% of the patients in group 2. The average per-patient cost of neuroimaging with CT/CTA was USD 1,460.00, with CT and MRI/MRA USD 1,569 and with CT/CTA and brain MRI USD 2,090.00 (p < 0.01). Conclusion: Either MRI/MRA or CT/CTA might be sufficient for the evaluation of patients with TIA or small asymptomatic strokes. If head CT at the ED is bypassed, a brain MRI with MRA of the head and neck would be the most informative tool at the lowest cost. Prospective studies with larger numbers of patients are needed for a better understanding of the safety and cost of imaging tools used for patients with TIA.

There is a growing interest in the application of real-time (fMRI) with neurofeedback training (NFT) to the treatment of disorders associated with abnormal brain function. Chronic tinnitus is one such disorder that is often characterized by hyperactivity of the primary auditory cortex (A1) and decreased activity of the ventromedial prefrontal cortex (vmPFC).

Major advances in the physics and technology for the production and utilization of laser-polarized He-3 and Xe-129 have resulted from this DARPA-sponsored research. A high-capacity polarizer and accumulator for Xe-129 has been developed and has been successfully transferred to the commercial sector. We have developed a powerful new method for imaging the three-dimensional distribution of the electronic spin polarization of the alkalimetal vapors used for spin-exchange optical pumping of He-3 and Xe-129. Absolute electronic spin polarizations are obtained. We have demonstrated that the intrinsic spin-exchange efficiency for polarizing He-3 is ten times better with optically pumped K vapor than with the currently used Rb vapor. Using equipment with key technological features resulting from this work, collaborators at the University of Virginia Medical School now make routine use of He-3 lung images of patients scheduled for lung resection surgery.

Major advances in the physics and technology for the production and utilization of laser-polarized He-3 and Xe-129 have resulted from this DARPA-sponsored research. A high-capacity polarizer and accumulator for Xe-129 has been developed and has been successfully transferred to the commercial sector. We have developed a powerful new method for imaging the three-dimensional distribution of the electronic spin polarization of the alkalimetal vapors used for spin-exchange optical pumping of He-3 and Xe-129. Absolute electronic spin polarizations are obtained. We have demonstrated that the intrinsic spin-exchange efficiency for polarizing He-3 is ten times better with optically pumped K vapor than with the currently used Rb vapor. Using equipment with key technological features resulting from this work, collaborators at the University of Virginia Medical School now make routine use of He-3 lung images of patients scheduled for lung resection surgery.

The analytical expression for the signal-to-noise ratio of a slotted surface coil with an arbitrary number of slots was derived using the quasi-static approach. This surface coil based on the vane-type magnetron tube. To study the coil perfomance, the theoretical signal-to-noise ratio predictions of this coil design were computed using a different number of slots. Results were also compared with theoretical results obtained for a circular coil with similar dimensions. It can be appreciated that slotted surface coil performance improves as the number of coils increases and, outperformed the circular-shaped coil. This makes it a good candidate for other MRI applications involving coil array techniques.

The analytical expression for the signal-to-noise ratio of a slotted surface coil with an arbitrary number of slots was derived using the quasi-static approach. This surface coil based on the vane-type magnetron tube. To study the coil perfomance, the theoretical signal-to-noise ratio predictions of this coil design were computed using a different number of slots. Results were also compared with theoretical results obtained for a circular coil with similar dimensions. It can be appreciated that slotted surface coil performance improves as the number of coils increases and, outperformed the circular-shaped coil. This makes it a good candidate for other MRI applications involving coil array techniques.

The analytical expression for the signal-to-noise ratio of a slotted surface coil with an arbitrary number of slots was derived using the quasi-static approach. This surface coil based on the vane-type magnetron tube. To study the coil perfomance, the theoretical signal-to-noise ratio predictions of this coil design were computed using a different number of slots. Results were also compared with theoretical results obtained for a circular coil with similar dimensions. It can be appreciated that slotted surface coil performance improves as the number of coils increases and, outperformed the circular-shaped coil. This makes it a good candidate for other MRI applications involving coil array techniques.

A number of physiological changes were demonstrated in bone, muscle, and blood from exposure of humans and animals to microgravity. Determining mechanisms and the development of effective countermeasures for long-duration space missions is an important NASA goal. Historically, NASA has had to rely on tape measures, x-ray, and metabolic balance studies with collection of excreta and blood specimens to obtain this information. The development of magnetic resonance imaging (MRI) offers the possibility of greatly extending these early studies in ways not previously possible; MRI is also non-invasive and safe; i.e., no radiation exposure. MRI provides both superb anatomical images for volume measurements of individual structures and quantification of chemical/physical changes induced in the examined tissues. This investigation will apply MRI technology to measure muscle, intervertebral disc, and bone marrow changes resulting from exposure to microgravity.

A number of physiological changes were demonstrated in bone, muscle, and blood from exposure of humans and animals to microgravity. Determining mechanisms and the development of effective countermeasures for long-duration space missions is an important NASA goal. Historically, NASA has had to rely on tape measures, x-ray, and metabolic balance studies with collection of excreta and blood specimens to obtain this information. The development of magnetic resonance imaging (MRI) offers the possibility of greatly extending these early studies in ways not previously possible; MRI is also non-invasive and safe; i.e., no radiation exposure. MRI provides both superb anatomical images for volume measurements of individual structures and quantification of chemical/physical changes induced in the examined tissues. This investigation will apply MRI technology to measure muscle, intervertebral disc, and bone marrow changes resulting from exposure to microgravity.

This article is from Journal of Cardiovascular Magnetic Resonance , volume 16 . Abstract None

This article is from Clinical and Experimental Otorhinolaryngology , volume 5 . Abstract Objectives: In this study, we compared the magnetic resonance (MR) image artifacts caused by a conventional metal-based cochlear implant and a newly developed liquid crystal polymer (LCP)-based device. Methods: The metal-based cochlear implant system (Nurobiosys Co.) was attached to side of the head of a subject and the LCP-based device was attached to opposite side. In both devices, alignment magnets were removed for safety. Magnetic resonance imaging (MRI) was performed on a widely used 3.0 T and an ultra-high 7.0 T MRI machine. 3.0 and 7.0 T MR images were acquired using T1- and T2*-weighted gradient echo sequences, respectively. Results: In the 3.0 T images, the metal-based device on the left side generated the significant amount of artifacts. The MR images in the proximity of the metal package were obscured by the artifacts in both axial and sagittal views. On the other hand, the MR images near the LCP-based device were relatively free from the artifacts and clearly showed the brain structures. 7.0 T MR images showed the more severe distortion in the both sides but the metal-based cochlear implant system caused a much larger obscure area than the LCP-based system. Conclusion: The novel LCP-based cochlear implant provides a good MRI compatibility beyond present-day cochlear implants. Thus, MR images can be obtained from the subjects even with the implanted LCP-based neural prosthetic systems providing useful diagnostic information. Furthermore, it will be also useful for functional MRI studies of the auditory perception mechanism after cochlear implantations as well as for positron emission tomography-MRI hybrid imaging.

This article is from PLoS ONE , volume 8 . Abstract Background: The purpose of the present study was to compare the image quality of spinal magnetic resonance (MR) imaging performed on a high-field horizontal open versus a short-bore MR scanner in a randomized controlled study setup. Methods: Altogether, 93 (80% women, mean age 53) consecutive patients underwent spine imaging after random assignement to a 1-T horizontal open MR scanner with a vertical magnetic field or a 1.5-T short-bore MR scanner. This patient subset was part of a larger cohort. Image quality was assessed by determining qualitative parameters, signal-to-noise (SNR) and contrast-to-noise ratios (CNR), and quantitative contour sharpness. Results: The image quality parameters were higher for short-bore MR imaging. Regarding all sequences, the relative differences were 39% for the mean overall qualitative image quality, 53% for the mean SNR values, and 34–37% for the quantitative contour sharpness (P

Magnetic Resonance Imaging 1996: Volume 14 , Issue Contents. Digitized from IA1652604-05 . Previous issue: sim_magnetic-resonance-imaging_1995_13_8 . Next issue: sim_magnetic-resonance-imaging_1996_14_1 .

Magnetic Resonance Imaging 1996: Volume 14 , Issue Contents. Digitized from IA1652604-05 . Previous issue: sim_magnetic-resonance-imaging_1995_13_8 . Next issue: sim_magnetic-resonance-imaging_1996_14_1 .

Quantum control of individual spins in condensed matter systems is an emerging field with wide-ranging applications in spintronics, quantum computation, and sensitive magnetometry. Recent experiments have demonstrated the ability to address and manipulate single electron spins through either optical or electrical techniques. However, it is a challenge to extend individual spin control to nanoscale multi-electron systems, as individual spins are often irresolvable with existing methods. Here we demonstrate that coherent individual spin control can be achieved with few-nm resolution for proximal electron spins by performing single-spin magnetic resonance imaging (MRI), which is realized via a scanning magnetic field gradient that is both strong enough to achieve nanometric spatial resolution and sufficiently stable for coherent spin manipulations. We apply this scanning field-gradient MRI technique to electronic spins in nitrogen-vacancy (NV) centers in diamond and achieve nanometric resolution in imaging, characterization, and manipulation of individual spins. For NV centers, our results in individual spin control demonstrate an improvement of nearly two orders of magnitude in spatial resolution compared to conventional optical diffraction-limited techniques. This scanning-field-gradient microscope enables a wide range of applications including materials characterization, spin entanglement, and nanoscale magnetometry.

Alzheimer’s disease (AD) is a gradually progressing neurodegenerative irreversible disorder. Mild cognitive impairment convertible (MCIc) is the clinical forerunner of AD. Precise diagnosis of MCIc is essential for effective treatments to reduce the progressing rate of the disease. The other cognitive states included in this study are mild cognitive impairment non-convertible (MCInc) and cognitively normal (CN). MCInc is a stage in which aged people suffer from memory problems, but the stage will not lead to AD. The classification between MCIc and MCInc is crucial for the early detection of AD. In this work, an algorithm is proposed which concatenates the output layers of Xception, InceptionV3, and MobileNet pre-trained models. The algorithm is tested on the baseline T1-weighted structural magnetic resonance imaging (MRI) images obtained from Alzheimer’s disease neuroimaging initiative database. The proposed algorithm provided multi-class classification accuracy of 85%. Also, the proposed algorithm gave an accuracy of 85% for classifying MCIc vs MCInc, an accuracy of 94% for classifying AD vs CN, and an accuracy of 92% for classifying MCIc vs CN. The results exhibit that the proposed algorithm outruns other state-of-the-art methods for the multi-class classification and classification between MCIc and MCInc.

Alzheimer’s disease (AD) is a gradually progressing neurodegenerative irreversible disorder. Mild cognitive impairment convertible (MCIc) is the clinical forerunner of AD. Precise diagnosis of MCIc is essential for effective treatments to reduce the progressing rate of the disease. The other cognitive states included in this study are mild cognitive impairment non-convertible (MCInc) and cognitively normal (CN). MCInc is a stage in which aged people suffer from memory problems, but the stage will not lead to AD. The classification between MCIc and MCInc is crucial for the early detection of AD. In this work, an algorithm is proposed which concatenates the output layers of Xception, InceptionV3, and MobileNet pre-trained models. The algorithm is tested on the baseline T1-weighted structural magnetic resonance imaging (MRI) images obtained from Alzheimer’s disease neuroimaging initiative database. The proposed algorithm provided multi-class classification accuracy of 85%. Also, the proposed algorithm gave an accuracy of 85% for classifying MCIc vs MCInc, an accuracy of 94% for classifying AD vs CN, and an accuracy of 92% for classifying MCIc vs CN. The results exhibit that the proposed algorithm outruns other state-of-the-art methods for the multi-class classification and classification between MCIc and MCInc.

We propose a novel compressed sensing technique to accelerate the magnetic resonance imaging (MRI) acquisition process. The method, coined spread spectrum MRI or simply s2MRI, consists of pre-modulating the signal of interest by a linear chirp before random k-space under-sampling, and then reconstructing the signal with non-linear algorithms that promote sparsity. The effectiveness of the procedure is theoretically underpinned by the optimization of the coherence between the sparsity and sensing bases. The proposed technique is thoroughly studied by means of numerical simulations, as well as phantom and in vivo experiments on a 7T scanner. Our results suggest that s2MRI performs better than state-of-the-art variable density k-space under-sampling approaches

We summarize the key advances resulting from our research program supported by ARO award W911NF-09-1-0147 between July 15, 2009 and July 14, 2013. We have used ultra-sensitive Magnetic Resonance Force Microscopy detection Electron Spin Resonance, using (ESRMRFM), to perform spatially resolved scanned probe studies of spin dynamics in nanoscale ensembles of few electron spins of varying size. Our research culminated in observation that the distinction between two channels of energy flow from and within a spin system, typically characterized the spin-lattice relaxation time T_1 and the spin-spin relaxation time T_2 that are rigorously distinct in macroscopic systems become indistinguishable in nanoscale systems. This is because spin transport mediated by mutual spin flip-flop diffusion---arising from a T_2-like process---in a nanoscale quasi-1D spin nanowire can transfer energy from the measured spin system to the thermal reservoir outside the measured volume---behavior typical of T_1 processes. The spin nanowire we created in diamond by means of patterned nitrogen ion implantation represents an intriguing prototype element of a spintronic device in an attractive and widely used wide band gap semiconductor. ESR-MRFM, a scanned probe method capable of spatially resolved magnetic resonance detection, offers a powerful approach to understanding the spin properties and dynamics in the device-like environments where their dynamics and lifetime will be influenced by nanoscale confinement. Our theoretical model that explains the observed spin dynamics in confined nanoscale spin structures are supported by extensive numerical modeling that agree well with our experimental data. Using our understanding of the electron spin dynamics in confined nanoscale structures, we developed an improved measurement protocol, pi-OSCAR, that we that we used to demonstrate spectroscopic measurements on nanoscale spin ensembles of few electron spins. Our demonstration of nanoscale

This project aims to identify the neural correlates of creativity optimization through a coordinate-based meta-analysis of task-based fMRI studies. We focus on three empirically supported optimization pathways: (1) short-term cognitive training, (2) long-term domain-specific expertise, and (3) dispositional creativity, as reflected by comparisons between individuals with high and low creativity. Using the Seed-based d Mapping (SDM) approach, we will assess whether these distinct enhancement strategies converge on shared brain activation patterns during creative task performance.

vi, 234 pages : 25 cm

vi, 234 pages : 25 cm

vi, 234 pages : 25 cm

vi, 234 pages : 25 cm

Here, a brain tumor classification method using the support vector machine (SVM) algorithm by utilizing discrete wavelet transform (DWT) transformation and feature extraction of gray-level co-occurrence matrix (GLCM) and local binary pattern (LBP) has been implemented using the magnetic resonance imaging (MRI) image belong to the low-grade glioma (LGG) or high-grade glioma (HGG) group. SVM algorithm used as a classification method has been widely used in research that raises the topic of classification. Through the formation of a hyperplane between 2 data classes, the SVM algorithm can be said to be a reliable method but does not require complicated computations. The DWT transformation is intended to provide clearer feature details from the MRI image, so that when the feature extraction algorithm is applied, it is expected that the extracted features will differ between benign tumor MRI images and malignant tumor MRI images. In 1 level DWT using high-low (HL) sub-band yield the highest specificity, sensitivity, and accuracy than using 3 levels using HL or low-high (LH) sub-band in LGG MRI image.Compared with another research, our proposed method is slightly better in terms of accuracy to classify the brain tumor image with achieved the accuracy of 98.6486%.

Here, a brain tumor classification method using the support vector machine (SVM) algorithm by utilizing discrete wavelet transform (DWT) transformation and feature extraction of gray-level co-occurrence matrix (GLCM) and local binary pattern (LBP) has been implemented using the magnetic resonance imaging (MRI) image belong to the low-grade glioma (LGG) or high-grade glioma (HGG) group. SVM algorithm used as a classification method has been widely used in research that raises the topic of classification. Through the formation of a hyperplane between 2 data classes, the SVM algorithm can be said to be a reliable method but does not require complicated computations. The DWT transformation is intended to provide clearer feature details from the MRI image, so that when the feature extraction algorithm is applied, it is expected that the extracted features will differ between benign tumor MRI images and malignant tumor MRI images. In 1 level DWT using high-low (HL) sub-band yield the highest specificity, sensitivity, and accuracy than using 3 levels using HL or low-high (LH) sub-band in LGG MRI image.Compared with another research, our proposed method is slightly better in terms of accuracy to classify the brain tumor image with achieved the accuracy of 98.6486%.

Secure Euclidean random distribution for patients’ magnetic resonance imaging privacy protection

The purpose of the scoping review is to examine the current state of the literature on resting state functional magnetic resonance imaging (fMRI) after pediatric and adolescent mild traumatic brain injury (TBI) in order to summarize the findings, the methodological approaches used, and to identify areas for future research. Mild TBI is an important public health issue. Currently, no objective neurobiological biomarkers are available to help physicians predict which children will take longer to recover from a mild TBI. Traditional neuroimaging techniques are often not sensitive to detecting injury after a mild TBI with research shifting to investigate advance imaging techniques. One such advanced imaging technique is resting state fMRI, which examines intrinsic network connectivity and can assess multiple sensory, motor, and cognitive networks in a relatively short amount of time. Although there have been reviews examining neuroimaging of pediatric mild TBI across different modalities, to the best of our knowledge, no review has specifically focused on resting state fMRI.

Gliosarcoma is a rare type of glioma, a cancer of the brain that comes from glial, or supportive, brain cells, as opposed to the neural brain cells. Gliosarcoma is a malignant cancer, and is defined as a glioblastoma consisting of gliomatous and sarcomatous componentsThe aim of the study is to characterize the radiographic features of gliosarcoma, such as existence nature, content and appearance and enhancement on Computed Tomography and Magnetic Resonance Imaging. And also to find out which is the most effective imaging method to diagnose and categorize gliosarcoma. Fifteen patients were studied retrospectively from the PACS system of CT Scanner and MRI using the protocol of imaging of the head.The study reveals that majority(93.3%) of the gliosarcoma were single. About 80 percent of the gliosarcoma had both solid and cystic components. All fifteen tumors appeared to be relatively well demarcated from the surroundin normal or edematous brain parenchyma. On T2-weighted image eight shows of hyperintensity and isointensity.The study concludes that Gadolinium enhanced Magnetic Resonance Imaging is more accurate than plain MRI, plain CT, Contrast Enhanced CT in defining the margins of Gliosarcoma. Tamijeselvan S"Radio-graphical Features of Gliosarcoma on Computed Tomography and Magnetic Resonance Imaging" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-6 , October 2017, URL: http://www.ijtsrd.com/papers/ijtsrd4713.pdf Article URL: http://www.ijtsrd.com/medicine/radiology/4713/radio-graphical-features-of-gliosarcoma-on-computed--tomography-and-magnetic-resonance-imaging/tamijeselvan-s

To identify the quantitative magnetic resonance imaging techniques and measured biomarkers known in literature that can be utilised to assess both progression and risk of rupture of aortic aneurysms. And to summarise and disseminate the existing literature in this field, identify research gaps and make recommendations for future research.