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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.

Disturbing vocal hallucination during an MRI Session, dedicated to Tommy Cole. Part 2 in the 'Cranial Acres' series, a compilation of psychedelic and experimental sound installations.

Disturbing vocal hallucination during an MRI Session, dedicated to Tommy Cole. Part 2 in the 'Cranial Acres' series, a compilation of psychedelic and experimental sound installations.

The influence of La non magnetic impurities on the spin dynamics of CeCoIn$_{5}$ was studied by inelastic neutron scattering. In La-substituted systems, the spin resonance peak (observed at $\Omega_{res}=0.55 meV$ in the pure system) is shifted to lower energies but the ratio $\Omega_{res}/k_{B}T_{c}$ remains unchanged. The excitation broadens till it reaches 0.3 meV equal to the value of the quasi-elastic signal in the normal state. The evolution of La substitution is compared with the evolution of the magnetic resonance in Ni and Zn substituted YBa$_{2}$Cu$_{3}$O$_{7}$.

The influence of La non magnetic impurities on the spin dynamics of CeCoIn$_{5}$ was studied by inelastic neutron scattering. In La-substituted systems, the spin resonance peak (observed at $\Omega_{res}=0.55 meV$ in the pure system) is shifted to lower energies but the ratio $\Omega_{res}/k_{B}T_{c}$ remains unchanged. The excitation broadens till it reaches 0.3 meV equal to the value of the quasi-elastic signal in the normal state. The evolution of La substitution is compared with the evolution of the magnetic resonance in Ni and Zn substituted YBa$_{2}$Cu$_{3}$O$_{7}$.

Introduction.  Computed tomography (CT) and magnetic resonance imaging (MRI) are the main methods of radiation diagnostics, which allow to objectively assess the local prevalence of malignant tumors of the organ of hearing and decide on the possibility of surgical intervention. The purpose of the study  was to determine the main indications for surgical intervention, taking into account radiological criteria for lesions of the temporal bone (CT, MRI) in locally advanced skin cancer of the outer ear. Materials and methods. The present study is based on a retro- and prospective analysis of data from a comprehensive examination and treatment of 45 patients with locally advanced skin cancer of the external ear treated from 2021 to 2023. Results.  The prevalence of the tumor process in skin cancer of the external auditory canal in accordance with the staging system for tumor lesions of the structures of the temporal bone, developed in 1990 ( University of Pittsburgh ), taking into account CT and MRI signs of damage to the temporal bone and adjacent anatomical structures, a factor that significantly affects long-term results of treatment (for recurrence- free survival - risk ratio (RR) 4.76, 95% confidence interval (CI) 1, RR 4.25, 96% CI 1.74-10.4, p = 0.0017 for tumor-specific survival, RR 1.90, 94 % CI 1.07-3.58, p = 0.03). Conclusion. CT and MRI are mandatory methods of radiation diagnosis in patients with skin cancer of the external auditory canal.

Book Source: Digital Library of India Item 2015.192789 dc.contributor.author: Anil Kumar dc.date.accessioned: 2015-07-08T01:38:21Z dc.date.available: 2015-07-08T01:38:21Z dc.date.digitalpublicationdate: 2005-08-20 dc.identifier.barcode: 1990010091182 dc.identifier.origpath: /rawdataupload/upload/0091/182 dc.identifier.copyno: 1 dc.identifier.uri: http://www.new.dli.ernet.in/handle/2015/192789 dc.description.scannerno: 14 dc.description.scanningcentre: IIIT, Allahabad dc.description.main: 1 dc.description.tagged: 0 dc.description.totalpages: 210 dc.format.mimetype: application/pdf dc.language.iso: English dc.publisher: Indian Institute Of Technology Kanpur dc.rights: Out_of_copyright dc.source.library: Indian Institute Of Technology Kanpur dc.subject.classification: Technology dc.subject.classification: Engineering. Technology In General dc.subject.classification: Mechanical Engineering In General. Nuclear Technology. Electrical Engineering. Machinery dc.title: Nuclear Magnetic Relaxation In Coupled Spin System By Double Resonance

Book Source: Digital Library of India Item 2015.192789 dc.contributor.author: Anil Kumar dc.date.accessioned: 2015-07-08T01:38:21Z dc.date.available: 2015-07-08T01:38:21Z dc.date.digitalpublicationdate: 2005-08-20 dc.identifier.barcode: 1990010091182 dc.identifier.origpath: /rawdataupload/upload/0091/182 dc.identifier.copyno: 1 dc.identifier.uri: http://www.new.dli.ernet.in/handle/2015/192789 dc.description.scannerno: 14 dc.description.scanningcentre: IIIT, Allahabad dc.description.main: 1 dc.description.tagged: 0 dc.description.totalpages: 210 dc.format.mimetype: application/pdf dc.language.iso: English dc.publisher: Indian Institute Of Technology Kanpur dc.rights: Out_of_copyright dc.source.library: Indian Institute Of Technology Kanpur dc.subject.classification: Technology dc.subject.classification: Engineering. Technology In General dc.subject.classification: Mechanical Engineering In General. Nuclear Technology. Electrical Engineering. Machinery dc.title: Nuclear Magnetic Relaxation In Coupled Spin System By Double Resonance

This article is from Annals of Gastroenterology : Quarterly Publication of the Hellenic Society of Gastroenterology , volume 26 . Abstract Background: Dilated common bile duct (CBD) without obvious cause is a not uncommon finding on magnetic resonance cholangiopancreatography (MRCP). The aim of this study was to evaluate the diagnostic performance of endoscopic ultrasound (EUS) in patients with unexplained dilated CBD on MRCP. Methods: Patients referred for EUS evaluation of a dilated CBD were retrospectively analyzed with respect to serum alkaline phosphatase prior to EUS and subsequent outcome after EUS. Results: Over a 3-year period, 40 patients (24 males; mean age 38.9±9.9 years) with dilated CBD were retrospectively identified. Ten patients had elevated serum alkaline phosphatase. The diagnosis reached after EUS examination was: CBD stones in 15 (37.5%) with largest size of CBD stone being 9 mm, mass in CBD in 2 (5%), benign biliary stricture in 2 (5%), biliary stricture with underlying chronic pancreatitis in 1 (2.5%) patient respectively. EUS examination revealed normal CBD in 20 (50%) patients and two of these patients had periampullary diverticulum. All the patients with abnormal liver function tests had a detectable CBD pathology whereas 20/30 (66.6%) patients with normal liver biochemistry had normal EUS findings. There was no significant difference in the mean CBD diameter between the groups with demonstrable pathology compared with those without (P=0.64). Conclusion: EUS is a useful investigational modality for patients with unexplained dilated CBD on MRCP. The mean CBD diameter and the presence of normal liver function tests are not predictive of underlying pathology.

This article is from Annals of Gastroenterology : Quarterly Publication of the Hellenic Society of Gastroenterology , volume 26 . Abstract Background: Dilated common bile duct (CBD) without obvious cause is a not uncommon finding on magnetic resonance cholangiopancreatography (MRCP). The aim of this study was to evaluate the diagnostic performance of endoscopic ultrasound (EUS) in patients with unexplained dilated CBD on MRCP. Methods: Patients referred for EUS evaluation of a dilated CBD were retrospectively analyzed with respect to serum alkaline phosphatase prior to EUS and subsequent outcome after EUS. Results: Over a 3-year period, 40 patients (24 males; mean age 38.9±9.9 years) with dilated CBD were retrospectively identified. Ten patients had elevated serum alkaline phosphatase. The diagnosis reached after EUS examination was: CBD stones in 15 (37.5%) with largest size of CBD stone being 9 mm, mass in CBD in 2 (5%), benign biliary stricture in 2 (5%), biliary stricture with underlying chronic pancreatitis in 1 (2.5%) patient respectively. EUS examination revealed normal CBD in 20 (50%) patients and two of these patients had periampullary diverticulum. All the patients with abnormal liver function tests had a detectable CBD pathology whereas 20/30 (66.6%) patients with normal liver biochemistry had normal EUS findings. There was no significant difference in the mean CBD diameter between the groups with demonstrable pathology compared with those without (P=0.64). Conclusion: EUS is a useful investigational modality for patients with unexplained dilated CBD on MRCP. The mean CBD diameter and the presence of normal liver function tests are not predictive of underlying pathology.

This article is from Annals of Gastroenterology : Quarterly Publication of the Hellenic Society of Gastroenterology , volume 26 . Abstract Background: Dilated common bile duct (CBD) without obvious cause is a not uncommon finding on magnetic resonance cholangiopancreatography (MRCP). The aim of this study was to evaluate the diagnostic performance of endoscopic ultrasound (EUS) in patients with unexplained dilated CBD on MRCP. Methods: Patients referred for EUS evaluation of a dilated CBD were retrospectively analyzed with respect to serum alkaline phosphatase prior to EUS and subsequent outcome after EUS. Results: Over a 3-year period, 40 patients (24 males; mean age 38.9±9.9 years) with dilated CBD were retrospectively identified. Ten patients had elevated serum alkaline phosphatase. The diagnosis reached after EUS examination was: CBD stones in 15 (37.5%) with largest size of CBD stone being 9 mm, mass in CBD in 2 (5%), benign biliary stricture in 2 (5%), biliary stricture with underlying chronic pancreatitis in 1 (2.5%) patient respectively. EUS examination revealed normal CBD in 20 (50%) patients and two of these patients had periampullary diverticulum. All the patients with abnormal liver function tests had a detectable CBD pathology whereas 20/30 (66.6%) patients with normal liver biochemistry had normal EUS findings. There was no significant difference in the mean CBD diameter between the groups with demonstrable pathology compared with those without (P=0.64). Conclusion: EUS is a useful investigational modality for patients with unexplained dilated CBD on MRCP. The mean CBD diameter and the presence of normal liver function tests are not predictive of underlying pathology.

This article is from Annals of Gastroenterology : Quarterly Publication of the Hellenic Society of Gastroenterology , volume 26 . Abstract Background: Dilated common bile duct (CBD) without obvious cause is a not uncommon finding on magnetic resonance cholangiopancreatography (MRCP). The aim of this study was to evaluate the diagnostic performance of endoscopic ultrasound (EUS) in patients with unexplained dilated CBD on MRCP. Methods: Patients referred for EUS evaluation of a dilated CBD were retrospectively analyzed with respect to serum alkaline phosphatase prior to EUS and subsequent outcome after EUS. Results: Over a 3-year period, 40 patients (24 males; mean age 38.9±9.9 years) with dilated CBD were retrospectively identified. Ten patients had elevated serum alkaline phosphatase. The diagnosis reached after EUS examination was: CBD stones in 15 (37.5%) with largest size of CBD stone being 9 mm, mass in CBD in 2 (5%), benign biliary stricture in 2 (5%), biliary stricture with underlying chronic pancreatitis in 1 (2.5%) patient respectively. EUS examination revealed normal CBD in 20 (50%) patients and two of these patients had periampullary diverticulum. All the patients with abnormal liver function tests had a detectable CBD pathology whereas 20/30 (66.6%) patients with normal liver biochemistry had normal EUS findings. There was no significant difference in the mean CBD diameter between the groups with demonstrable pathology compared with those without (P=0.64). Conclusion: EUS is a useful investigational modality for patients with unexplained dilated CBD on MRCP. The mean CBD diameter and the presence of normal liver function tests are not predictive of underlying pathology.

This article is from Annals of Gastroenterology : Quarterly Publication of the Hellenic Society of Gastroenterology , volume 26 . Abstract Background: Dilated common bile duct (CBD) without obvious cause is a not uncommon finding on magnetic resonance cholangiopancreatography (MRCP). The aim of this study was to evaluate the diagnostic performance of endoscopic ultrasound (EUS) in patients with unexplained dilated CBD on MRCP. Methods: Patients referred for EUS evaluation of a dilated CBD were retrospectively analyzed with respect to serum alkaline phosphatase prior to EUS and subsequent outcome after EUS. Results: Over a 3-year period, 40 patients (24 males; mean age 38.9±9.9 years) with dilated CBD were retrospectively identified. Ten patients had elevated serum alkaline phosphatase. The diagnosis reached after EUS examination was: CBD stones in 15 (37.5%) with largest size of CBD stone being 9 mm, mass in CBD in 2 (5%), benign biliary stricture in 2 (5%), biliary stricture with underlying chronic pancreatitis in 1 (2.5%) patient respectively. EUS examination revealed normal CBD in 20 (50%) patients and two of these patients had periampullary diverticulum. All the patients with abnormal liver function tests had a detectable CBD pathology whereas 20/30 (66.6%) patients with normal liver biochemistry had normal EUS findings. There was no significant difference in the mean CBD diameter between the groups with demonstrable pathology compared with those without (P=0.64). Conclusion: EUS is a useful investigational modality for patients with unexplained dilated CBD on MRCP. The mean CBD diameter and the presence of normal liver function tests are not predictive of underlying pathology.

This article is from Journal of Cardiovascular Magnetic Resonance , volume 16 . Abstract Background: Cardiovascular disease in pregnancy is the leading cause of maternal mortality in North America. Although transthoracic echocardiography (TTE) is the most widely used imaging modality for the assessment of cardiovascular function during pregnancy, little is known on the role of cardiovascular magnetic resonance (CMR). The objective of the Cardiac Hemodynamic Imaging and Remodeling in Pregnancy (CHIRP) study was to compare TTE and CMR in the non-invasive assessment of maternal cardiac remodeling during the peripartum period. Methods: Between 2010–2012, healthy pregnant women aged 18 to 35 years were prospectively enrolled. All women underwent TTE and CMR during the third trimester and at least 3 months postpartum (surrogate for non-pregnant state). Results: The study population included a total of 34 women (mean age 29 ± 3 years). During the third trimester, TTE and CMR demonstrated an increase in left ventricular end-diastolic volume from 95 ± 11 mL to 115 ± 14 mL and 98 ± 6 mL to 125 ± 5 mL, respectively (p 

There can be few better examples of the complex and unanticipated interactions of basic research and technological innovation than the development of magnetic resonance imaging (NMR/MRI) techniques for multidisciplinary research. The method has the rather unusual and attractive features that it is totally non-destructive and non-invasive and for these reasons it has interesting applications in almost all fields of research. An ideal approach to exhaust the complex and unanticipated interactions of basic research and technological innovation offered by magnetic resonance techniques would be to find generalized ( time dependent and time independent) analytical solutions and models to the Bloch NMR equations. The advantages of such solutions are related to the fact that the magnetizations and signals obtainable from them may constitute an array of parameters that are uniquely informative for functional and dynamical studies of living and nonliving matters. Unfortunately, the basic physics of extracting the relevant information from the solution of Bloch NMR equations to accurately understand the theory, dynamics and applications of magnetic resonance imaging (MRI) is still not yet fully available. Additionally, it may be noteworthy to mention that, analytical solutions to the Bloch NMR flow equations have deliberately, perhaps unintentionally been omitted in the literature. Presently, there are no simple closed solutions known to the Bloch NMR flow equations for a general radiofrequency (rF) excitation. Therefore the Mathematical formulations and models based on the Bloch NMR flow equations presented in this book can be taken as definitions of new functions to be studied in detail. Volume I of this book is intended to present basic theory of MRI and develop several fundamental equations which can be invaluable for quantitative and qualitative analysis of NMR magnetizations and signals. Fortunately, analytical solutions to these equations are available in standard Mathematics, Physics, Chemistry and Engineering textbooks. These solutions can then be used to reveal without too much difficulty many of the most important but hidden applications of magnetic resonance imaging. Volume I is intentionally divided into only two chapters to focus the minds of our readers on the array of MRI innovations expected in Volume II.

This diskette contains a highly technical and useful NMR analysis program. Nuclear Magnetic Resonance is used in many advanced chemistry applications and this program allows the analysis of this technique. Written by a professor of chemistry at the University of South Florida, this package is unique in the fact that it displays the calculated spectrum including adjustable peak broadening. Simulated plotting of very complex molecules, such as protein spectra are also allowed. Parameters for up to 7 spins (nucleii) can be calculated.

The research performed over one year was to use electron paramagnetic resonance (EPR), electron nuclear double resonance (ENDOR), fourier transform infrared (FTIR) absorption, and other optical techniques to identify and characterize point defects in nonlinear optical materials. The materials studied were KTP, ZnGeP2, and CdGeAs2 families nonlinear optical crystals. Photoluminescence and micro-Raman techniques were found to be useful for clarifying the origin of near infrared emission in, and characterizing the decomposition process at the surface of KTP crystals. EPR spectra of ZnGeP2 indicate that near edge optical absorption is dominated by singly ionized zinc vacancies, and large concentrations of phosphorus vacancy donors were present as well. Photoluminescence studies further support that the optical absorption is likely due to several overlapping bands arising from an acceptor-to-donor transition and band-to-defect transitions.

During the first year we pursued studies of q-space imaging (QSI) of the spinal cord and myelin imaging. The QSI studies extended our previous work establishing our ability to define the distribution of axon fiber diameters using this noninvasive approach. This work was presented at the Annual Meeting of the International Society of Magnetic Resonance in Medicine in Montreal, May, 2011. In addition, we made great progress with an ultra-short TE (UTE) method for myelin imaging. Using this approach we were able to establish quantitative accuracy vs. MR spectroscopy and preparations with known myelin content. This method holds promise for extension to human subjects, and it could offer a unique opportunity to observe myelin without confounding by other axonal injury or edema. This work was presented at the Annual Meeting of the International Society of Magnetic Resonance in Medicine in Montreal, May, 2011, and at the Annual Meeting of the American Society of Neuroradiology in Seattle, June, 2011. A revised manuscript is currently under review at the Proceedings of the National Academy of Sciences.

In order to make evident pulsing brain arteries movements associated with heart activity, intramodality MR registration and subtraction has to be used to detect small differences between serial MR brain images. A new voxel-based rigid-body registration algorithm, including: (1) a standardization of grey levels procedure by means of similarity measure optimization, (2) a new full 2-D convolution cubic interpolation zooming procedure, (3) a low computational cost multi-scale iterative procedure, that uses the zoomed versions of images to be registered, is proposed. It allows up to 1/8 pixel accuracy.

The goal of this project is to test the hypotheses that: 1.) Subjects with GWI have reduced NAA in the basal ganglia and pons, which are not accounted for by confounds such as depression, post traumatic stress disorder, and alcoholism. 2.) Reduced NAA in basal ganglia and pons correlates with CNS signs and symptoms of GWI. Thus far we have mailed out a total of 505 letters describing our study. Dr Weiner appeared on several radio and TV programs, in response to our press release. Over 262 subjects have contacted us expressing interest in this study. Since we began enrolling subjects, we have largely met our goals of studying 2 subjects/week with the complete study battery which includes medical evaluation, neuropsychological testing, startle testing, MRI/MRS and the Haley Questionnaire. Thus far, we have studied a total of 84 subjects. At this time, 22 of these subjects have met the criteria for GWI and 26 are controls, with 36 having an intermediate classification. We currently have 5 subjects scheduled for study for the remainder of the month. Although some preliminary data analysis has been performed, at the current time the sample size is much too small for any formal data analysis.

This study assesses magnetic resonance (MR)-guided interstitial laser photocoagulation (ILP) for the treatment of breast cancer. ILP has been successfully used for the treatment of a variety of solid tumors, and recent studies have indicated the capability of ILP, which employs low level heat (^50 deg C) for about 10 minutes, to kill breast cancer tissue. As breast cancer cells are often interspersed with surrounding normal tissue, making boundaries difficult to define by most diagnostic imaging methods, MR imaging is used to define tumor margins and extent. Our research group has developed a high-contrast, high-resolution method for MR imaging of the breast, called RODEO (Rotating Delivery of Excitation Off-resonance), proven to have twice the sensitivity and specificity of mammography. Cellular death induced by ILP produces a phase change that can be visualized on MR images. This MRI hypointense zone can then be used to determine the adequacy of ILP treatment. The combination of RODEO imaging and a system for MRI-directed stereotaxic biopsy allows the accurate localization and placement of the laser fibers for ILP. This study tests the feasibility and outcome of MR-directed ILP in 30 patients with breast cancer who are scheduled for surgical removal of the lesion (mastectomy or lumpectomy). Our major findings to date are: (1) RODEO MRI can accurately identify cancers for laser ablation; (2) Stereotaxic MRI needle positioning can be performed; (3) Fast RODEO MR can accurately depict zones of ablation for interactive lip; (4) ILP is an effective method for the minimally invasive ablation of breast cancer; (5) MRI-guided ILP is safe and is a potential alternative to surgical lumpectomy; and (6) MRI-guided ILP may have lower costs and provide better cosmesis than surgical lumpectomy.

This research project employs nuclear magnetic resonance (NMR) spectroscopy to investigate the metabolic aspects of the toxicity associated perfluorinated carboxylic acids. Fluorine-19 NMR has been used to monitor the metabolic fate of perfluoro-n-octanoic acid (PFOA) and perfluoro-n-decanoic acid (PFDA) in the rat. Spectra obtained at various times following the administration of PFOA and PFDA depict the presence of the parent compounds in samples of bile, serum, urine, and liver in vivo. Urine spectra also indicate the presence of a possible metabolite which has not been identified at this time. Carbon-13 NMR is providing information regarding the effects of PFOA and PFDA on hepatic carbohydrate metabolism. Preliminary data indicate that hepatic glycogenesis is severely inhibited in rats at 3 days post treatment with PFDA. Plasma glucose and hepatic glucose appear to behave similar to control animals during the first three days post treatment with PFDA, but data obtained at days 6 and 7 indicate that hepatic glucose utilization may be slowed. These data are preliminary and experiments are currently in progress to further characterize the perfluorocarbon-induced dysfunctions of liver metabolism.

The purpose of this research is oriented towards understanding the reading, language, and articulation deficits associated with Neurofibromatosis Type 1 (NF-l) and relating these deficits to the underlying pathophysiology of NF-l as revealed by Magnetic Resonance Spectroscopy Imaging (MRSI). A second goal is to determine how differences in activation, as measured by functional Magnetic Resonance Imaging (fMRI), are linked to the cognitive/academic impairments associated with NF-l. A third goal is to further understand how T-2 weighted hyperintensities on Magnetic Resonance Imaging (MRI) scans are related to cognitive/academic impairments associated with NF-l. Each aim addresses the research in terms of pathophysiology and how cognitive/academic functioning of children with NF-l compares to control groups when examined in both genetic (i.e., sibling) as well as general population (both reading disabled and non-reading disabled) contexts. We hypothesize that abnormalities of NAA, Choline, or their ratios, will exist in the thalamus and will correlate with language, reading, and articulation deficits in NF-l, defined by lowering of the cognitive scores of each child with NF-l relative to his/her unaffected sibling. For the second goal, we hypothesize that children with NF-l will activate their brains similarly to reading disabled children during fMRI tasks. For the third goal, we hypothesize that reading, language, and articulation deficits will correlate with the number of brain locations with T2-weighted hyperintensities. Thus, neuroimaging permits the pursuit of furthering our understanding of how the NF-l gene affects the brain in terms of basic neurobiologic factors (ultrastructural, physiological, and localization) as well as their impacts on cognition (reading, language, and articulation) in NF-l.

Nuclear Magnetic Resonance (NMR) is a convenient and noninvasive means for studying the internal structure of diamagnetic substances. The extraction of length scale information in liquid NMR spectroscopy is largely limited to sizes below the diffusion length ( 50 microns). Breaking translational symmetry using the nuclear dipolar field imparts a scale dependence, and provides a means of measuring length scales above this limit. The use of the dipolar field in liquid NMR to make structural measurements is a relatively novel concept in the field, and previous techniques have been largely limited to test cases. This thesis examines the extraction of length-scale information from a relatively complex two-phase liquid system, specifically a poly-disperse oil/water emulsion. Theory is developed and then compared to experimental results, with good agreement. Simple scaling laws are identified which provide a simple means of using the technique for length scale measurements. The thesis then focuses on developing the theory and feasibility of using the developed dipolar NMR technique to study flowing systems, in order to extract average length scale and interfacial properties, including interfacial velocity and interfacial area.

The development of noninvasive methods for characterizing mammographically indeterminate lesions represents an active area of current research in medical imaging. In particular, much research effort is being directed toward the development of new techniques for measuring tumour blood flow. This thesis consists of experiments designed to evaluate the use of a magnetic resonance imaging technique called Intravoxel Incoherent Motion (IVIM) to produce microvascular flow images of breast lesions.

Receiver coil sensitivity for Materials Detection by magnetic resonance was investigated, comparing measurement strategies using one large coil and arrays of smaller coils. It is found that an array of smaller coils will result in improved sensitivity for detection of sample volumes which are small compared to the volume to be sampled, however one large coil will perform better for larger samples.

our primary accomplishments were the development of software for the computer-aided structure elucidation of structural features of biological systems based on NOESY data: (a) simulating accurate theoretical NOESY spectra based on structural models, motional assumptions and NMR experiment parameters; and (b) the automated extraction of modeling constraints directly from raw NOESY data. The most recent software developments are the incorporation of model-free order parameters into NOESY simulations and the addition of routines for comparing computer-extracted distances (or cross-rates) with the expectation ranges based on the full spectrum of torsional freedom so as to generate precision estimates for NOE-distances from a single NOESY spectrum. These methods have been used to define the conformational states of a variety of polypeptide and drug molecule systems including: prostaglandin and steroid analogs, peptide hormones such as dynorphin-related peptides and GNRH analogs, rigid and flexible endothelin analogs, and a small protein allergen. The methods have also been applied to receptor-bound peptides. Nuclear Magnetic Resonance, Molecular Recognition, NOESY Spectral Simulation, Structure Refinement, Software Development.

We have successfully developed a technical approach that can be employed to produce MRS spectra of the breast lesions as small as (6 mm)3. These methods have been applied to a cohort of 35 patients. Using the presence of choline in the MR spectra as an indicator of malignancy, the positive predictive value is 0.90. This observation indicates that MRS may be employed in several ways. First it may provide a method for the improved distinction between benign and malignant lesions. Second the presence of choline may provide a means for differentiating recurrent tumor from radiation induced fibrosis. Finally, changes in the choline peak may provide a means for assessing response to therapy in patients with locally advanced breast cancer. Each of these three methods merits further investigation. Future directions that this project may take include: (1) MRS studies of breast lesions at 4.0 T, (2) determining the incremental diagnostic efficiency of MRS, and (3) carrying; out an analysis of the cost effectiveness of MRS as a diagnostic method.

The low temperature near field scanning optical microscope was designed and constructed in the physics department at UCSB, and the associated optical equipment was purchased and successfully integrated. The resulting piece of equipment is one of the few running variable temperature magnetooptical NSOMs in the country.

Patients must remain immobile for magnetic resonance imaging. The majority of adult patients are able to remain immobile, however, this is very challenging for pediatric patients. Pediatric sedation is necessary to achieve this immobility while maintaining the heart rate, respirations, and pulse oximetry levels at the patient's base line values. The purpose of this study was to explore the combination sedative of ketamine, midazolam, and atropine administered intramuscularly and determine if it is safe and effective for pediatric patients undergoing magnetic resonance imaging.

Nuclear magnetic resonance (NMR) was studied for use in the nondestructive evaluation of composite materials, with particular emphasis on NMR imaging. NMR parameters of potential use for generating images showing high contrast between acceptable and unacceptable regions of composites were measured for typical organic matrix materials. The attenuating effects of carbon fibers were measured and relationships were developed to compute the conditions necessary to obtain images of carbon-fiber composites. NMR images of aerospace composites containing poly(aryl-ether-ether-ketone) (PEEK) and epoxy resins were obtained using solid state 13C techniques. The contrast mechanism used for these images was the composites. NMR images of hydrogen in PEEK were also obtained using multiple-pulse techniques to reduce dipolar broadening. Selective pulses were used to obtain images of the spatial variations in the crystalline content of PEEK. The results of these experiments were used to assess the feasibility of using NMR for nondestructive evaluation of composite materials.

Our overall goal is to characterize axonal and myelin damage in human spinal cord injury, its evolution over time, and response to therapy. Towards this end, we have developed a set of in-vivo magnetic resonance imaging methods. We have successfully implemented a refined high-resolution approach to imaging the transverse diffusion properties of human spinal cord in-vivo. This work reveals the internal architecture of the spinal cord white matter, not previously reported, and its distribution suggests that these diffusion results are driven by the diffusion barrier spacing. Kurtosis results support the complexity of the extracellular diffusion pathways as the primary determinant of these results. Prior work suggests that barrier spacing is largely a function of axon density, and indirectly related to the fiber diameter distribution. The imaging results also permit high-resolution identification of several white matter tracts, not otherwise visible in-vivo. We have also implemented in-vivo human subject spinal cord myelin imaging using an inhomogeneous magnetization transfer (ihMT) approach. Prior work with this method indicates that it is sensitive to myelin content, and not confounded by edema or diffusion barrier spacing. Thus, diffusion and ihMT methods combine to offer independent assessment of axonal architecture (diffusion) and myelin content (ihMT). As both methods have been accomplished in-vivo in human subjects, this work will lead directly to characterization of axonal response to spinal cord injury in patients.

In recent years there have been several incidents with helicopters where magnetic resonance imagers (MRIs) have interfered with the operation of magnetic sensors such as compasses and directional gyroscopes. The magnetic fields generated by the MRI magnet causes magnetic sensors to give aberrant readings. This report documents the characteristics of MRIs and how they operate. It discusses relevant federal regulations of MRI and all magnetic effects and hazards involved with operating helicopters in a strong static magnetic field for both personnel and equipment. Finally, the report makes recommendations for safe helicopter operations in and around MRIs.

This report outlines our progress regarding toxicological studies of perfluoro- n-octanoic acid (PFOA) and perfluoro-n-decanoic acid (PFDA). These Air Force chemicals belong to a class of compounds known as peroxisome proliferators (PP). Many PP cause hepatotoxicity and carcinogenesis in rodents. The mechanisms are unknown and represent an active area of research. Recent studies have demonstrated specific effects of PFDA treatment on hepatic phospholipid and carbohydrate metabolism. PFDA alters hepatic glucose transport. PFDA-treated rats showed rates of glucose transport which were 2-fold less than controls. PFDA treatment also caused a 3-fold increase in liver diacylglycerol (DAG): PFOA had no effect. This DAG is derived from phosphatidylcholine via phospholipase C activity. Since DAG stimulates protein kinase C (PKC), these data suggest that the hepatotoxic effects of PFDA may be initiated through a PKC response. Accordingly, experiments are in progress to investigate the effects of PFDA on liver PKC activity; preliminary data are presented herein. In other studies, preliminary data indicate that the influence of PFDA on phospholipid metabolism occurs at doses well below the LD50. Also, in studies involving C8-C11 perifluoro- carboxylic acids, only chain lengths C9 affect phospholipid metabolism. These data suggest that the metabolic effects may be related to the compound's ability to diffuse into membranes. This research furthers our understanding of the mechanisms involved in the hepatotoxicity associated with these Air Force chemicals.

Nanometer-scale magnetic resonance imaging (Nano-MRI) has the potential to be a powerful tool to investigate and characterize materials. The goal of the proposed research program is to develop fundamentally new approaches in force-detected magnetic resonance techniques and achieve nanometer-scale nuclear spin imaging by: (1) achieving sub-attonewton force sensitivity using ultra-sensitive rf nanowire mechanical resonators, (2) generating intense pulsed field gradients greater than 106 T/m on the nanometer scale, (3) developing efficient spin imaging protocols using time-dependent B_0 and B_1 gradients, compatible with imaging statistical polarization. During the first year of the ARO grant, we developed a new method for nanometer-scale pulsed nuclear magnetic resonance imaging and spectroscopy. In the first proof-of-concept experiments, we demonstrated two-dimensional Fourier transform images of proton spins in a polystyrene sample with 10 nm spatial resolution. This new paradigm in force-detected NMR allows well-established spectroscopic and imaging pulsed NMR techniques to be applied to the nanometer scale. In the coming year, our goal is to extend the spatial resolution to be between 1-3-nm, obtain three-dimensional tomographic images, and perform high-resolution NMR spectroscopy on the nanometer scale.

Standard evaluations of NF- 1 tumor and treatment response are inadequate and current therapies are ineffective. We conducted studies using MRI, MRS, and PET in 28 NF-1 patients with newly-diagnosed brain tumors and 7 with progressive tumors. Preliminary results show MRS and PET profiles similar to non-NF1 tumors. Predictive factors have not been identified. However, thalamic hypometabolism and hypoperfusion is significant in these patients. Neuroimaging data requires re-analysis in 9 months after all scheduled studies are completed. To address these problems, we conducted multimodality neuroimaging studies in NF-1 patients with newly-diagnosed or progressive optic nerve/hypothalamic or brain stem tumors to predict the growth potential of these tumor and a randomized clinical trial of new antitumor agents in progressively enlarging OPT/HT and plexiform neurofibromas to rapidly identify potentially effective therapies.

Three marginal oscillator circuits are evaluated in their signal-to- noise performance in a complete nuclear magnetic resonance spectrometer. A circuit based on the hybrid Darlington source follower is superior to the other two, a modified Donnally oscillator and an FET cascade oscillator. Also the hybrid Darlington circuit has a voltage gain of 0.95 as compared, respectively, to 0.79 and 0.53 for the other two circuits. A sensitive but easy to understand phase sensitive detector of original design is presented as an integral part of the system, allowing simultaneous observation of the Lorentzian absorption signal and its derivative. Another new development is an external RF injection mode of operation of the marginal oscillators which permits observation of easily saturated NMR lines. Using this system, the variation of proton line widths in water as a function of the concentration of paramagnetic CuSO4 in the water is presented. Theses.

In most of the applications where polymers are used, more than one phase is present. In addition to the polymer matrix, the second phase may be comprised of the same or a different polymer, or of some type of filler or fiber which is typically a solid or solid-like. Typical applications of these materials include use in: structural composites; adhesives; chromatography; protective coatings; elastomers; and particle stabilization and separation. A brief review of the use of magnetic resonance of polymer molecules attached to solid surfaces is given with examples from the author's laboratory. Liquid, solid (including wide-line and magic angle spinning), and two dimensional magnetic resonance experiments have all been performed on surface polymers. The results suggest how magnetic resonance techniques can be used to probe the dynamics and structure of the polymer in composites, dispersions, surface treatments and the drying of coating.

A new scheme for denoising magnetic resonance spectroscopy signals is presented. The scheme is based on projecting noisy signals on different time- frequency domains, consecutively, and performing noise filtering operations in these domains according to the noise level. The evaluation of this scheme was performed using extensive simulation of magnetic resonance spectroscopy signals with different noise levels. It was observed that this scheme gives superior results that compensate for the excess computational requirements, especially for very low signal to noise ratio signals.

A computer study at X-band frequencies of the threshold fields for subsidiary resonance phenomena in a wide range of magnetic materials has been conducted. The variation of the critical power for spin-wave excitation has been determined as a function of the material parameters combined with the geometry of the ferrite material. The investigation has shown that, at a given frequency, low-level operation of microwave devices that utilize subsidiary resonance absorption requires a material with a very narrow spin-wave linewidth and a saturation magnetization in the order of 5000 gauss. The optimum material geometry that yields the lowest threshold is the case where the demagnetizing factor N sub z = 0, where z represents the direction of the applied dc field, and the transverse demagnetizing factors N sub x and N sub y are equal to 0.5. (Author)

Mice are widely used in the study of breast cancer to increase understanding of cancer development and to evaluate new therapies. Noninvasive imaging methods are a crucial component of the effective use of mouse models of breast cancer. However prior imaging studies of mammary cancer in mice have focused on large palpable tumors at an advanced stage of invasion that are rarely orthotopic and are poor models for the human cancers commonly seen clinically. Here high resolution MR was used to image spontaneous early and nonpalpable cancers transgenic mouse model of breast cancer. After correlation with histology MRI was able to clearly detect large 5mm tumors small nonpalpable 0.51.5mm tumors and even smaller ducts distended with preinvasive ductal carcinoma in situ 300500 microns in diameter with very high sensitivity and specificity. This is the first report of in vivo imaging of early spontaneous mouse mammary cancer. Because of its similarity to human breast cancer in vivo MRI of early orthotopic murine mammary cancer will be an important tool for real time study of the development and progression of breast cancer in vivo. These techniques can be used to develop new therapies that target early breast cancer and to find new ways of detecting early breast cancer.

Mice are widely used in the study of breast cancer to increase understanding of cancer development and to evaluate new therapies. Noninvasive imaging methods are a crucial component of the effective use of mouse models of breast cancer. However prior imaging studies of mammary cancer in mice have focused on large palpable tumors at an advanced stage of invasion that are rarely orthotopic and are poor models for the human cancers commonly seen clinically. Here high resolution MR was used to image spontaneous early and nonpalpable cancers transgenic mouse model of breast cancer. After correlation with histology MRI was able to clearly detect large 5mm tumors small nonpalpable 0.51.5mm tumors and even smaller ducts distended with preinvasive ductal carcinoma in situ 300500 microns in diameter with very high sensitivity and specificity. This is the first report of in vivo imaging of early spontaneous mouse mammary cancer. Because of its similarity to human breast cancer in vivo MRI of early orthotopic murine mammary cancer will be an important tool for real time study of the development and progression of breast cancer in vivo. These techniques can be used to develop new therapies that target early breast cancer and to find new ways of detecting early breast cancer.

The report presents the results of an investigation of Barium excitation by molecular beam magnetic resonance techniques. The results of both depopulation and ionization experiments are consistent and confirm that the metastable states in barium are strong contributors to photoionization in barium clouds under solar radiation. The depopulation experiments indicate that the major losses occur due to photons near 3005 A and that considerable metastable density increases occur when the atomic barium beam is subjected to a full light spectrum. The ionization experiments show that roughly half of the photo- ionization (for equally populated metastables) occurs from the singlets and half from the triplet metastable states. The report also presents a discussion of the mechanisms that decrease metal atom densities with emphasis on barium oxide, aluminum oxide and boron oxide reactions.

Qualitative and semi-quantitative examination of the temperature dependence of the RCH2-Mg proton n.m.r. spectra of several Grignard reagents indicates that the rate of inversion at this center is relatively insensitive to the structure of the group R. Secondary Grignard reagents invert much more slowly, if at all. The dependence of the inversion rate of the primary organometallic compounds on solvent character and on added salts suggests that inversion proceeds by means of a mechanism having kinetic order greater than one.

This article is from Indian Journal of Medical and Paediatric Oncology : Official Journal of Indian Society of Medical & Paediatric Oncology , volume 32 . Abstract Sinus histicytosis (Rosai–Dorfman disease) is a rare, benign granulomatous disease that typically presents with massive cervical lymphadenopathy. Extranodal involvement along with concomitant nodal disease occurs in about 43% of cases. We present a unique case of a 30-year-old male with cervical, retroperitoneal lymphadenopathy, associated with renal and pituitary sellar masses.

This article is from Journal of Cardiovascular Magnetic Resonance , volume 14 . Abstract Background: Intramyocardialhemorrhage (IMH) reflects severe reperfusion injury in acute myocardial infarction. Non-invasive detection of IMH by cardiovascular magnetic resonance (CMR) may serve as a surrogate marker to evaluate the effect of preventive measures to reduce reperfusion injury and hence provide additional prognostic information. We sought to investigate whether IMH could be detected by CMR exploiting the T1 shortening effect of methemoglobin in an experimental model of acute myocardial infarction. The results were compared to T2-weighthed short tau inversion recovery (T2-STIR), and T2*-weighted(T2*W) sequences. Methods and results: IMH was induced in ten 40 kg pigs by 50-min balloon occlusion of the mid LAD followed by reperfusion. Between 4–9 days (average 4.8) post-injury, the left ventricular myocardium was assessed by T1-weigthed Inversion Recovery(T1W-IR), T2-STIR, and T2*Wsequences. All CMR images were matched to histopathology and compared with the area of IMH. The difference between the size of the IMH area detected on T1W-IR images and pathology was −1.6 ± 11.3% (limits of agreement, -24%–21%), for the T2*W images the difference was −0.1 ± 18.3% (limitsof agreement, -36.8%–36.6%), and for T2-STIR the difference was 8.0 ± 15.5% (limits of agreement, -23%–39%). By T1W IR the diagnostic sensitivity of IMH was 90% and specificity 70%, for T2*W imaging the sensitivity was 70% and specificity 50%, and for T2-STIR sensitivity for imaging IMH was 50% and specificity 60%. Conclusion: T1-weigthednon-contrast enhanced CMR detects IMH with high sensitivity and specificity and may become a diagnostic tool for detection of IMH in patients with myocardial infarction.

This article is from The Pan African Medical Journal , volume 14 . Abstract Hydatid disease is endemic in Tunisia and has been considered as one of the most common surgical pathology. Several localizations have been described, but hydatidosis of the liver is the most frequent clinical entity. Primary hydatid cyst of the gallbladder is very rare. We report in this observation a new case of primary hydatid cyst of the gallbladder diagnosed by Magnetic Resonance Imaging (MRI).

This article is from International Archives of Medicine , volume 4 . Abstract Background: The diagnosis of constrictive pericarditis continues to be a clinical challenge. Magnetic resonance imaging provides excellent visualization of the pericardium. The aim of our study is to clarify the contribution of this non invasive exploration in the diagnosis of constrictive pericarditis in our center. Methods: we conducted a prospective study over a period of two years, since 2008, covering a series of patients (n = 11), mean age 44 ± 15 years, in whom constrictive pericarditis was suspected clinically and on transthoracic echocardiography. We studied its characteristics on magnetic resonance imaging. Results: Magnetic resonance imaging confirmed the diagnosis showing pericardial thickening in all cases, measuring 8.2 +/- 2.6 mm on average, circumferential in 64%, and localized in 36%. The imaging data, particularly pericardial thickening and its topography, were confirmed by surgical exploration, and results were concordant in all cases. Conclusion: Magnetic resonance imaging is a powerful tool to establish constrictive pericarditis diagnosis.

This article is from Psychiatry Investigation , volume 9 . Abstract Here, we report psychotic symptoms together with a right cerebellopontine-angle lesion. A37-year-old female patient presented with a trigeminal Schwannoma occupying the right cerebellopontine angle. Her psychotic symptoms included auditory hallucinations and delusions of persecution. T1- and T2-weighted images on magnetic resonance imaging (MRI) revealed hyperintense and hypointense areas in the right cerebellopontine angle, respectively. The clinical and neuroimaging reviews in this case suggest that sudden onset of psychotic symptoms at a mature age may be associated with a right cerebellopontine-angle lesion and that MRI should be used to evaluate possible organic bases in patients that present with psychosis.