WorldWideScience

Sample records for previous mri studies

  1. An fMRI study of neuronal activation in schizophrenia patients with and without previous cannabis use

    Directory of Open Access Journals (Sweden)

    Else-Marie eLøberg

    2012-10-01

    Full Text Available Previous studies have mostly shown positive effects of cannabis use on cognition in patients with schizophrenia, which could reflect lower neurocognitive vulnerability. There are however no studies comparing whether such cognitive differences have neuronal correlates. Thus, the aim of the present study was to compare whether patients with previous cannabis use differ in brain activation from patients who has never used cannabis. The patients groups were compared on the ability to up-regulate an effort mode network during a cognitive task and down-regulate activation in the same network during a task-absent condition. Task-present and task-absent brain activation was measured by functional magnetic resonance neuroimaging (fMRI. Twenty-six patients with a DSM-IV and ICD-10 diagnosis of schizophrenia were grouped into a previous cannabis user group and a no-cannabis group. An auditory dichotic listening task with instructions of attention focus on either the right or left ear stimulus was used to tap verbal processing, attention and cognitive control, calculated as an aggregate score. When comparing the two groups, there were remaining activations in the task-present condition for the cannabis group, not seen in the no-cannabis group, while there was remaining activation in the task-absent condition for the no-cannabis group, not seen in the cannabis group. Thus, the patients with previous cannabis use showed increased activation in an effort mode network and decreased activation in the default mode network as compared to the no-cannabis group. It is concluded that the present study show some differences in brain activation to a cognitively challenging task between previous cannabis and no-cannabis schizophrenia patients.

  2. Mediastinal involvement in lymphangiomatosis: a previously unreported MRI sign

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Vikas; Shah, Sachit; Barnacle, Alex; McHugh, Kieran [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Sebire, Neil J. [Great Ormond Street Hospital for Children, Department of Histopathology, London (United Kingdom); Brock, Penelope [Great Ormond Street Hospital for Children, Department of Oncology, London (United Kingdom); Harper, John I. [Great Ormond Street Hospital for Children, Department of Dermatology, London (United Kingdom)

    2011-08-15

    Multifocal lymphangiomatosis is a rare systemic disorder affecting children. Due to its rarity and wide spectrum of clinical, histological and imaging features, establishing the diagnosis of multifocal lymphangiomatosis can be challenging. The purpose of this study was to describe a new imaging sign in this disorder: paraspinal soft tissue and signal abnormality at MRI. We retrospectively reviewed the imaging, clinical and histopathological findings in a cohort of eight children with thoracic involvement from this condition. Evidence of paraspinal chest disease was identified at MRI and CT in all eight of these children. The changes comprise heterogeneous intermediate-to-high signal parallel to the thoracic vertebrae on T2-weighted sequences at MRI, with abnormal paraspinal soft tissue at CT and plain radiography. Multifocal lymphangiomatosis is a rare disorder with a broad range of clinicopathological and imaging features. MRI allows complete evaluation of disease extent without the use of ionising radiation and has allowed us to describe a previously unreported imaging sign in this disorder, namely, heterogeneous hyperintense signal in abnormal paraspinal tissue on T2-weighted images. (orig.)

  3. Functional MRI of the visual cortex and visual testing in patients with previous optic neuritis

    DEFF Research Database (Denmark)

    Langkilde, Annika Reynberg; Frederiksen, J.L.; Rostrup, Egill

    2002-01-01

    to both the results of the contrast sensitivity test and to the Snellen visual acuity. Our results indicate that fMRI is a useful method for the study of ON, even in cases where the visual acuity is severely impaired. The reduction in activated volume could be explained as a reduced neuronal input......The volume of cortical activation as detected by functional magnetic resonance imaging (fMRI) in the visual cortex has previously been shown to be reduced following optic neuritis (ON). In order to understand the cause of this change, we studied the cortical activation, both the size...... of the activated area and the signal change following ON, and compared the results with results of neuroophthalmological testing. We studied nine patients with previous acute ON and 10 healthy persons served as controls using fMRI with visual stimulation. In addition to a reduced activated volume, patients showed...

  4. Patellar calcar: MRI appearance of a previously undescribed anatomical entity

    International Nuclear Information System (INIS)

    Collins, Mark S.; Tiegs-Heiden, Christin A.; Stuart, Michael J.

    2014-01-01

    The femoral calcar is a constant anatomical structure within the proximal femur representing a condensation of bone trabeculae. It is our impression that a similar structure is present within the patella. The purpose of this retrospective study was to define the prevalence, appearance, location, and configuration of the patellar calcar on MRI examinations. One hundred consecutive unenhanced knee MRIs were retrospectively reviewed by two readers who were blinded to the clinical indication. The patellar calcar was defined as a dark signaling, linear or curvilinear structure subjacent to the patellar articular surface. If present, the patellar calcar was assigned to a ''well seen,'' ''moderately well seen,'' or ''faintly seen'' category. Location of the calcar within the patella, orientation, configuration, and thickness were recorded. Confounding variables, such as marrow edema, patellar chondromalacia, bipartite patella, or postoperative changes were also recorded. The patellar calcar was visualized in 81 out of 100 (81 %) MRIs. When detected, the calcar was well seen in 20 out of 81 (25 %), moderately well seen in 35 out of 81 (43 %), and faintly seen in 26 out of 81 (32 %). The anteroposterior width of the calcar measured at its thickest segment was: 1 mm in 10 out of 81 (12 %). The patellar calcar was seen in the majority of knee MRIs and had a consistent imaging appearance. The calcar may be obscured by degenerative arthrosis of the patella and rarely may mimic patellar stress fracture or osteochondritis dissecans. Radiologists and clinicians should be familiar with this normal anatomical structure. (orig.)

  5. Patellar calcar: MRI appearance of a previously undescribed anatomical entity

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Mark S.; Tiegs-Heiden, Christin A. [Department of Radiology, Mayo Clinic, Rochester, Minnesota (United States); Stuart, Michael J. [Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota (United States)

    2014-02-15

    The femoral calcar is a constant anatomical structure within the proximal femur representing a condensation of bone trabeculae. It is our impression that a similar structure is present within the patella. The purpose of this retrospective study was to define the prevalence, appearance, location, and configuration of the patellar calcar on MRI examinations. One hundred consecutive unenhanced knee MRIs were retrospectively reviewed by two readers who were blinded to the clinical indication. The patellar calcar was defined as a dark signaling, linear or curvilinear structure subjacent to the patellar articular surface. If present, the patellar calcar was assigned to a ''well seen,'' ''moderately well seen,'' or ''faintly seen'' category. Location of the calcar within the patella, orientation, configuration, and thickness were recorded. Confounding variables, such as marrow edema, patellar chondromalacia, bipartite patella, or postoperative changes were also recorded. The patellar calcar was visualized in 81 out of 100 (81 %) MRIs. When detected, the calcar was well seen in 20 out of 81 (25 %), moderately well seen in 35 out of 81 (43 %), and faintly seen in 26 out of 81 (32 %). The anteroposterior width of the calcar measured at its thickest segment was: < 1 mm in 43 out of 81 (53 %), 1 mm in 28 out of 81 (35 %), and >1 mm in 10 out of 81 (12 %). The patellar calcar was seen in the majority of knee MRIs and had a consistent imaging appearance. The calcar may be obscured by degenerative arthrosis of the patella and rarely may mimic patellar stress fracture or osteochondritis dissecans. Radiologists and clinicians should be familiar with this normal anatomical structure. (orig.)

  6. De novo adamantinomatous craniopharyngioma presenting anew in an elderly patient with previous normal CT and MRI studies: A case report and implications on pathogenesis

    Directory of Open Access Journals (Sweden)

    Amy Walker, B.S.

    2015-09-01

    Full Text Available Adamantinomatous craniopharyngiomas are histologically benign epithelial tumors which arise from embryonic remnants of the craniopharyngeal duct and Rathke’s pouch. They are thought to have a congenital origin and are histologically unique from papillary craniopharyngioma. We describe the case of an elderly male who presented with symptoms related to a large craniopharyngioma with previously normal brain magnetic resonance and computed tomography imaging studies. These findings dispute the embryogenic theory that craniopharyngiomas observed in adults develop from the persistent slow growth of embryonic remnants.

  7. MRI case studies

    International Nuclear Information System (INIS)

    Huggett, S.; Barber, J.

    1989-01-01

    Three case studies are presented to show the value of magnetic resonance imaging used in conjunction with other imaging techniques. In each case MRI proved a vital diagnostic tool and superior to CT in showing firstly the haematoma in a patient with aphasia and right-sided weakness, secondly the size of the disc herniation in a patient with severe leg and ankle pains and thirdly the existence of a metastatic lesion in a patient with a previous history of breast cancer. 11 figs

  8. Functional MRI of the visual cortex and visual testing in patients with previous optic neuritis

    DEFF Research Database (Denmark)

    Langkilde, Annika Reynberg; Frederiksen, J.L.; Rostrup, Egill

    2002-01-01

    of the activated area and the signal change following ON, and compared the results with results of neuroophthalmological testing. We studied nine patients with previous acute ON and 10 healthy persons served as controls using fMRI with visual stimulation. In addition to a reduced activated volume, patients showed...... a reduced blood oxygenation level dependent (BOLD) signal increase and a greater asymmetry in the visual cortex, compared with controls. The volume of visual cortical activation was significantly correlated to the result of the contrast sensitivity test. The BOLD signal increase correlated significantly......The volume of cortical activation as detected by functional magnetic resonance imaging (fMRI) in the visual cortex has previously been shown to be reduced following optic neuritis (ON). In order to understand the cause of this change, we studied the cortical activation, both the size...

  9. Studying neuroanatomy using MRI.

    Science.gov (United States)

    Lerch, Jason P; van der Kouwe, André J W; Raznahan, Armin; Paus, Tomáš; Johansen-Berg, Heidi; Miller, Karla L; Smith, Stephen M; Fischl, Bruce; Sotiropoulos, Stamatios N

    2017-02-23

    The study of neuroanatomy using imaging enables key insights into how our brains function, are shaped by genes and environment, and change with development, aging and disease. Developments in MRI acquisition, image processing and data modeling have been key to these advances. However, MRI provides an indirect measurement of the biological signals we aim to investigate. Thus, artifacts and key questions of correct interpretation can confound the readouts provided by anatomical MRI. In this review we provide an overview of the methods for measuring macro- and mesoscopic structure and for inferring microstructural properties; we also describe key artifacts and confounds that can lead to incorrect conclusions. Ultimately, we believe that, although methods need to improve and caution is required in interpretation, structural MRI continues to have great promise in furthering our understanding of how the brain works.

  10. On the Tengiz petroleum deposit previous study

    International Nuclear Information System (INIS)

    Nysangaliev, A.N.; Kuspangaliev, T.K.

    1997-01-01

    Tengiz petroleum deposit previous study is described. Some consideration about structure of productive formation, specific characteristic properties of petroleum-bearing collectors are presented. Recommendation on their detail study and using of experience on exploration and development of petroleum deposit which have analogy on most important geological and industrial parameters are given. (author)

  11. Imaging tools to study pharmacology: functional MRI on small rodents

    Directory of Open Access Journals (Sweden)

    Elisabeth eJonckers

    2015-10-01

    Full Text Available Functional Magnetic Resonance Imaging (fMRI is an excellent tool to study the effect of pharmacological modulations on brain function in a non-invasive and longitudinal manner. We introduce several blood oxygenation level dependent (BOLD fMRI techniques, including resting state (rsfMRI, stimulus-evoked (st-fMRI, and pharmacological MRI (phMRI. Respectively, these techniques permit the assessment of functional connectivity during rest as well as brain activation triggered by sensory stimulation and/or a pharmacological challenge. The first part of this review describes the physiological basis of BOLD fMRI and the hemodynamic response on which the MRI contrast is based. Specific emphasis goes to possible effects of anaesthesia and the animal’s physiological conditions on neural activity and the hemodynamic response. The second part of this review describes applications of the aforementioned techniques in pharmacologically-induced, as well as in traumatic and transgenic disease models and illustrates how multiple fMRI methods can be applied successfully to evaluate different aspects of a specific disorder. For example, fMRI techniques can be used to pinpoint the neural substrate of a disease beyond previously defined hypothesis-driven regions-of-interest (ROIs. In addition, fMRI techniques allow one to dissect how specific modifications (e.g. treatment, lesion etc. modulate the functioning of specific brain areas (st-fMRI, phMRI and how functional connectivity (rsfMRI between several brain regions is affected, both in acute and extended time frames. Furthermore, fMRI techniques can be used to assess/explore the efficacy of novel treatments in depth, both in fundamental research as well as in preclinical settings. In conclusion, by describing several exemplary studies, we aim to highlight the advantages of functional MRI in exploring the acute and long-term effects of pharmacological substances and/or pathology on brain functioning along with

  12. In vivo dentate nucleus MRI relaxometry correlates with previous administration of Gadolinium-based contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Tedeschi, Enrico; Canna, Antonietta; Cocozza, Sirio; Russo, Carmela; Angelini, Valentina; Brunetti, Arturo [University ' ' Federico II' ' , Neuroradiology, Department of Advanced Biomedical Sciences, Naples (Italy); Palma, Giuseppe; Quarantelli, Mario [National Research Council, Institute of Biostructure and Bioimaging, Naples (Italy); Borrelli, Pasquale; Salvatore, Marco [IRCCS SDN, Naples (Italy); Lanzillo, Roberta; Postiglione, Emanuela; Morra, Vincenzo Brescia [University ' ' Federico II' ' , Department of Neurosciences, Reproductive and Odontostomatological Sciences, Naples (Italy)

    2016-12-15

    To evaluate changes in T1 and T2* relaxometry of dentate nuclei (DN) with respect to the number of previous administrations of Gadolinium-based contrast agents (GBCA). In 74 relapsing-remitting multiple sclerosis (RR-MS) patients with variable disease duration (9.8±6.8 years) and severity (Expanded Disability Status Scale scores:3.1±0.9), the DN R1 (1/T1) and R2* (1/T2*) relaxation rates were measured using two unenhanced 3D Dual-Echo spoiled Gradient-Echo sequences with different flip angles. Correlations of the number of previous GBCA administrations with DN R1 and R2* relaxation rates were tested, including gender and age effect, in a multivariate regression analysis. The DN R1 (normalized by brainstem) significantly correlated with the number of GBCA administrations (p<0.001), maintaining the same significance even when including MS-related factors. Instead, the DN R2* values correlated only with age (p=0.003), and not with GBCA administrations (p=0.67). In a subgroup of 35 patients for whom the administered GBCA subtype was known, the effect of GBCA on DN R1 appeared mainly related to linear GBCA. In RR-MS patients, the number of previous GBCA administrations correlates with R1 relaxation rates of DN, while R2* values remain unaffected, suggesting that T1-shortening in these patients is related to the amount of Gadolinium given. (orig.)

  13. An fMRI study

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 38; Issue 5 ... Alcoholism; brain; fMRI; language processing; lexical; semantic judgment ... alcohol dependence is associated with neurocognitive deficits in tasks requiring memory, perceptual ...

  14. Personality disorders in previously detained adolescent females: a prospective study

    NARCIS (Netherlands)

    Krabbendam, A.; Colins, O.F.; Doreleijers, T.A.H.; van der Molen, E.; Beekman, A.T.F.; Vermeiren, R.R.J.M.

    2015-01-01

    This longitudinal study investigated the predictive value of trauma and mental health problems for the development of antisocial personality disorder (ASPD) and borderline personality disorder (BPD) in previously detained women. The participants were 229 detained adolescent females who were assessed

  15. Imaging tools to study pharmacology: functional MRI on small rodents

    OpenAIRE

    Elisabeth eJonckers; Disha eShah; Julie eHamaide; Marleen eVerhoye; Annemie eVan Der Linden

    2015-01-01

    Functional Magnetic Resonance Imaging (fMRI) is an excellent tool to study the effect of pharmacological modulations on brain function in a non-invasive and longitudinal manner. We introduce several blood oxygenation level dependent (BOLD) fMRI techniques, including resting state (rsfMRI), stimulus-evoked (st-fMRI), and pharmacological MRI (phMRI). Respectively, these techniques permit the assessment of functional connectivity during rest as well as brain activation triggered by sensory stimu...

  16. Retrospective review of previous minor leak before major subarachnoid hemorrhage diagnosed by MRI as a predictor of occurrence of symptomatic delayed cerebral ischemia.

    Science.gov (United States)

    Oda, Shinri; Shimoda, Masami; Hirayama, Akihiro; Imai, Masaaki; Komatsu, Fuminari; Shigematsu, Hideaki; Nishiyama, Jun; Hotta, Kazuko; Matsumae, Mitsunori

    2018-02-01

    OBJECTIVE This study attempted to determine whether a previous minor leak correlated with the occurrence of symptomatic delayed cerebral ischemia (sDCI). METHODS The authors retrospectively evaluated sDCI-related clinical features and findings from MRI, including T1-weighted imaging (T1WI)-FLAIR mismatch at the time of admission, in 151 patients admitted with subarachnoid hemorrhage (SAH) within 48 hours of ictus. RESULTS The overall incidence of sDCI was 23% (35 of 151 patients). In all subjects, multivariate analysis revealed that World Federation of Neurosurgical Societies Grades II-V, age 70 years or older, presence of rebleeding after admission, a previous minor leak before the major SAH attack as diagnosed by T1WI-FLAIR mismatch, acute infarction on diffusion-weighted imaging, and CT SAH score were significantly associated with occurrence of sDCI. In patients with no previous minor leak before major SAH as diagnosed by T1WI-FLAIR mismatch, the incidence of sDCI was only 7% (7 of 97 patients). CONCLUSIONS A previous minor leak before major SAH as diagnosed by T1WI-FLAIR mismatch represents an important sDCI-related factor. When the analysis was restricted to patients with true acute SAH without a previous minor leak diagnosed by T1WI-FLAIR mismatch, the incidence of sDCI was extremely low.

  17. Dynamic MRI study for breast tumors

    International Nuclear Information System (INIS)

    Seki, Tsuneaki

    1990-01-01

    Application of MRI for diagnosis of breast tumors was retrospectively examined in 103 consecutive cases. Contrast enhancement, mostly by dynamic study, was performed in 83 cases using Gd-DTPA and 0.5 T superconductive apparatus. Results were compared to those of mammography and sonography. On dynamic study, carcinoma showed abrupt rise of signal intensity with clear-cut peak formation in early phase, while benign fibroadenoma showed slow rise of signal intensity and prolonged enhancement without peak formation. In 12 of 33 carcinomas (33%), peripheral ring enhancement was noted reflecting vascular stroma of histologic sections. All fibroadenomas showed homogenous enhancement without peripheral ring. In MRI, sensitivity, specificity, and accuracy were 86%, 96%, 91%. In mammography 82%, 95%, 87% and in ultrasonography 91%, 95%, 93%. Although MRI should not be regarded as routine diagnostic procedure because of expense and limited availability, it may afford useful additional information when standard mammographic findings are not conclusive. (author)

  18. Radon anomalies prior to earthquakes (1). Review of previous studies

    International Nuclear Information System (INIS)

    Ishikawa, Tetsuo; Tokonami, Shinji; Yasuoka, Yumi; Shinogi, Masaki; Nagahama, Hiroyuki; Omori, Yasutaka; Kawada, Yusuke

    2008-01-01

    The relationship between radon anomalies and earthquakes has been studied for more than 30 years. However, most of the studies dealt with radon in soil gas or in groundwater. Before the 1995 Hyogoken-Nanbu earthquake, an anomalous increase of atmospheric radon was observed at Kobe Pharmaceutical University. The increase was well fitted with a mathematical model related to earthquake fault dynamics. This paper reports the significance of this observation, reviewing previous studies on radon anomaly before earthquakes. Groundwater/soil radon measurements for earthquake prediction began in 1970's in Japan as well as foreign countries. One of the most famous studies in Japan is groundwater radon anomaly before the 1978 Izu-Oshima-kinkai earthquake. We have recognized the significance of radon in earthquake prediction research, but recently its limitation was also pointed out. Some researchers are looking for a better indicator for precursors; simultaneous measurements of radon and other gases are new trials in recent studies. Contrary to soil/groundwater radon, we have not paid much attention to atmospheric radon before earthquakes. However, it might be possible to detect precursors in atmospheric radon before a large earthquake. In the next issues, we will discuss the details of the anomalous atmospheric radon data observed before the Hyogoken-Nanbu earthquake. (author)

  19. Biopsy guided by real-time sonography fused with MRI: a phantom study

    DEFF Research Database (Denmark)

    Ewertsen, C.; Grossjohann, Hanne Sønder; Nielsen, Kristina Rue

    2008-01-01

    OBJECTIVE: The purpose of our study was to test the accuracy of sonographically guided biopsies in a phantom of structures not visible on sonography but shown on MRI by using commercially available sonography systems with image fusion software. MATERIALS AND METHODS: A previously recorded MRI...

  20. An fMRI study of Agency

    DEFF Research Database (Denmark)

    Charalampaki, Angeliki

    2017-01-01

    Motor area has a distinct directionality, depending on the stage of the volitional movement. In this study, we were interested in assessing the neuronal mechanism underlying this phenomenon. We therefore performed an fMRI study of Agency, to exploit the high spatial resolution this imaging technique...... displays. For the purposes of our study twenty participants were recruited. The experimental procedure we considered appropriate to study the Sense of Agency, involved participants laying inside the fMRI scanner and while they had no visual feedback of their hand, they were instructed to draw straight...... lines on a tablet with a digital pen. They could only see the consequences of their movement as a cursor’s movement on a screen. After finishing their movement, participants were requested to make a judgment over whether they felt they were the Agent of the observed movement or not. The analysis of our...

  1. IClinfMRI Software for Integrating Functional MRI Techniques in Presurgical Mapping and Clinical Studies.

    Science.gov (United States)

    Hsu, Ai-Ling; Hou, Ping; Johnson, Jason M; Wu, Changwei W; Noll, Kyle R; Prabhu, Sujit S; Ferguson, Sherise D; Kumar, Vinodh A; Schomer, Donald F; Hazle, John D; Chen, Jyh-Horng; Liu, Ho-Ling

    2018-01-01

    Task-evoked and resting-state (rs) functional magnetic resonance imaging (fMRI) techniques have been applied to the clinical management of neurological diseases, exemplified by presurgical localization of eloquent cortex, to assist neurosurgeons in maximizing resection while preserving brain functions. In addition, recent studies have recommended incorporating cerebrovascular reactivity (CVR) imaging into clinical fMRI to evaluate the risk of lesion-induced neurovascular uncoupling (NVU). Although each of these imaging techniques possesses its own advantage for presurgical mapping, a specialized clinical software that integrates the three complementary techniques and promptly outputs the analyzed results to radiology and surgical navigation systems in a clinical format is still lacking. We developed the Integrated fMRI for Clinical Research (IClinfMRI) software to facilitate these needs. Beyond the independent processing of task-fMRI, rs-fMRI, and CVR mapping, IClinfMRI encompasses three unique functions: (1) supporting the interactive rs-fMRI mapping while visualizing task-fMRI results (or results from published meta-analysis) as a guidance map, (2) indicating/visualizing the NVU potential on analyzed fMRI maps, and (3) exporting these advanced mapping results in a Digital Imaging and Communications in Medicine (DICOM) format that are ready to export to a picture archiving and communication system (PACS) and a surgical navigation system. In summary, IClinfMRI has the merits of efficiently translating and integrating state-of-the-art imaging techniques for presurgical functional mapping and clinical fMRI studies.

  2. How the risky features of previous selection affect subsequent decision-making: evidence from behavioral and fMRI measures.

    Science.gov (United States)

    Dong, Guangheng; Zhang, Yifen; Xu, Jiaojing; Lin, Xiao; Du, Xiaoxia

    2015-01-01

    Human decision making is rarely conducted in temporal isolation. It is often biased and affected by environmental variables, particularly prior selections. In this study, we used a task that simulates a real gambling process to explore the effect of the risky features of a previous selection on subsequent decision making. Compared with decision making after an advantageous risk-taking situation (Risk_Adv), that after a disadvantageous risk-taking situation (Risk_Disadv) is associated with a longer response time (RT, the time spent in making decisions) and higher brain activations in the caudate and the dorsolateral prefrontal cortex (DLPFC). Compared with decisions after Risk_Adv, those after Risk_Disadv in loss trials are associated with higher brain activations in the left superior temporal gyrus (STG) and the precuneus. Brain activity and relevant RTs significantly correlated. Overall, people who experience disadvantageous risk-taking selections tend to focus on current decision making and engage cognitive endeavors in value evaluation and in the regulation of their risk-taking behaviors during decision making.

  3. MRI

    DEFF Research Database (Denmark)

    Schroeter, Aileen; Rudin, Markus; Gianolio, Eliana

    2017-01-01

    This chapter discusses principles of nuclear magnetic resonance (NMR) and MRI followed by a survey on the major classes of MRI contrast agents (CA), their modes of action, and some of the most significative applications. The two more established classes of MRI-CA are represented by paramagnetic...... been attained that markedly increase the number and typology of systems with CEST properties. Currently much attention is also devoted to hyperpolarized molecules that display a sensitivity enhancement sufficient for their direct exploitation for the formation of the MR image. A real breakthrough...

  4. To see bruxism: a functional MRI study.

    Science.gov (United States)

    Yılmaz, S

    2015-01-01

    Since the pathophysiology of bruxism is not clearly understood, there exists no possible treatment. The aim of this study is to investigate the cerebral activation differences between healthy subjects and patients with bruxism on behalf of possible aetiological factors. 12 healthy subjects and 12 patients with bruxism, a total of 24 right-handed female subjects (aged 20-27 years) were examined using functional MRI during tooth-clenching and resting tasks. Imaging was performed with 3.0-T MRI scanner with a 32-channel head coil. Differences in regional brain activity between patients with bruxism and healthy subjects (control group) were observed with BrainVoyager QX 2.8 (Brain Innovation, Maastricht, Netherlands) statistical data analysis program. Activation maps were created using the general linear model: single study and multistudy multisubject for statistical group analysis. This protocol was approved by the ethics committee of medical faculty of Kirikkale University, Turkey (02/04), based on the guidelines set forth in the Declaration of Helsinki. The group analysis revealed a statistically significant increase in blood oxygenation level-dependent signal of three clusters in the control group (pbruxism. Our findings indicate that there was a decrease of cortical activation pattern in patients with bruxism in clenching tasks. This indicates decreased blood flow and activation in regional neuronal activity. Bruxism, as an oral motor disorder concerns dentistry, neurology and psychiatry. These results might improve the understanding and physiological handling of sleep bruxism.

  5. MRI

    Science.gov (United States)

    ... the room. Pins, hairpins, metal zippers, and similar metallic items can distort the images. Removable dental work ... an MRI can cause heart pacemakers and other implants not to work as well. The magnets can ...

  6. MRI Compatibility of Robot Actuation Techniques – A Comparative Study

    OpenAIRE

    Fischer, Gregory S.; Krieger, Axel; Iordachita, Iulian; Csoma, Csaba; Whitcomb, Louis L.; Fichtinger, Gabor

    2008-01-01

    This paper reports an experimental evaluation of the following three different MRI-compatible actuators: a Shinsei ultrasonic motor, a Nanomotion ultrasonic motor and a pneumatic cylinder actuator. We report the results of a study comparing the effect of these actuators on the signal to noise ratio (SNR) of MRI images under a variety of experimental conditions. Evaluation was performed with the controller inside and outside the scanner room and with both 1.5T and 3T MRI scanners. Pneumatic cy...

  7. Close relationship between fMRI signals and transient heart rate changes accompanying K-complex. Simultaneous EEG/fMRI study

    International Nuclear Information System (INIS)

    Kan, Shigeyuki; Koike, Takahiko; Miyauchi, Satoru; Misaki, Masaya

    2009-01-01

    Combining functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) allows the investigation of spontaneous activities in the human brain. Recently, by using this technique, increases in fMRI signal accompanying transient EEG activities such as sleep spindles and slow waves were reported. Although these fMRI signal increases appear to arise as a result of the neural activities being reflected in the EEG, when the influence of physiological activities upon fMRI signals are taken into consideration, it is highly controversial that fMRI signal increases accompanying transient EEG activities reflect actual neural activities. In the present study, we conducted simultaneous fMRI and polysomnograph recording of 18 normal adults, to study the effect of transient heart rate changes after a K-complex on fMRI signals. Significant fMRI signal increase was observed in the cerebellum, the ventral thalamus, the dorsal part of the brainstem, the periventricular white matter and the ventricle (quadrigeminal cistern). On the other hand, significant fMRI signal decrease was observed only in the right insula. Moreover, intensities of fMRI signal increase that was accompanied by a K-complex correlated positively with the magnitude of heart rate changes after a K-complex. Previous studies have reported that K-complex is closely related with sympathetic nervous activity and that the attributes of perfusion regulation in the brain differ during wakefulness and sleep. By taking these findings into consideration, our present results indicate that a close relationship exists between a K-complex and the changes in cardio- and neurovascular regulations that are mediated by the autonomic nervous system during sleep; further, these results indicate that transient heart rate changes after a K-complex can affect the fMRI signal generated in certain brain regions. (author)

  8. Regional differences in the CBF and BOLD responses to hypercapnia: a combined PET and fMRI study

    DEFF Research Database (Denmark)

    Rostrup, Egill; Law, I; Blinkenberg, M

    2000-01-01

    Previous fMRI studies of the cerebrovascular response to hypercapnia have shown signal change in cerebral gray matter, but not in white matter. Therefore, the objective of the present study was to compare (15)O PET and T *(2)-weighted MRI during a hypercapnic challenge. The measurements were perf...

  9. Assessment of apical periodontitis by MRI. A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Geibel, M.A. [Ulm Univ. (Germany). Oral and Maxillofacial Surgery; Schreiber, E.S.; Bracher, A.K.; Rasche, V. [Ulm Univ. (Germany). Internal Medicine II; Hell, E.; Ulrici, J. [Sirona Dental Systems GmbH, Bensheim (Germany). Dental Imaging; Sailer, L.K. [DOC Praxisklinik im Wiley, Neu-Ulm (Germany). MKG; Ozpeynirci, Y. [Ulm Univ. (Germany). Diagnostic and Interventional Radiology

    2015-04-15

    The purpose of this clinical feasibility study was to evaluate the applicability of magnetic resonance imaging (MRI) for the assessment of apical periodontitis in direct comparison with cone beam CT (CBCT). 19 consecutive patients (average age 43 ± 13 years) with 34 lesions in total (13 molars, 14 premolars and 7 front teeth) were enrolled in this feasibility study. Periapical lesions were defined as periapical radiolucencies (CBCT) or structural changes in the spongy bone signal (MRI), which were connected with the apical part of a root and with at least twice the width of the periodontal ligament space. The location and dimension of the lesions were compared between MRI and CBCT. While mainly mineralized tissue components such as teeth and bone were visible with CBCT, complimentary information of the soft tissue components was assessable with MRI. The MRI images provided sufficient diagnostic detail for the assessment of the main structures of interest. Heterogeneous contrast was observed within the lesion, with often a clear enhancement close to the apical foramen and the periodontal gap. No difference for lesion visibility was observed between MRI and CBCT. The lesion dimensions corresponded well, but were slightly but significantly overestimated with MRI. A heterogeneous lesion appearance was observed in several patients. Four patients presented with a well circumscribed hyperintense signal in the vicinity of the apical foramen. The MRI capability of soft tissue characterization may facilitate detailed analysis of periapical lesions. This clinical study confirms the applicability of multi-contrast MRI for the identification of periapical lesions.

  10. Assessment of apical periodontitis by MRI. A feasibility study

    International Nuclear Information System (INIS)

    Geibel, M.A.; Schreiber, E.S.; Bracher, A.K.; Rasche, V.; Hell, E.; Ulrici, J.; Sailer, L.K.; Ozpeynirci, Y.

    2015-01-01

    The purpose of this clinical feasibility study was to evaluate the applicability of magnetic resonance imaging (MRI) for the assessment of apical periodontitis in direct comparison with cone beam CT (CBCT). 19 consecutive patients (average age 43 ± 13 years) with 34 lesions in total (13 molars, 14 premolars and 7 front teeth) were enrolled in this feasibility study. Periapical lesions were defined as periapical radiolucencies (CBCT) or structural changes in the spongy bone signal (MRI), which were connected with the apical part of a root and with at least twice the width of the periodontal ligament space. The location and dimension of the lesions were compared between MRI and CBCT. While mainly mineralized tissue components such as teeth and bone were visible with CBCT, complimentary information of the soft tissue components was assessable with MRI. The MRI images provided sufficient diagnostic detail for the assessment of the main structures of interest. Heterogeneous contrast was observed within the lesion, with often a clear enhancement close to the apical foramen and the periodontal gap. No difference for lesion visibility was observed between MRI and CBCT. The lesion dimensions corresponded well, but were slightly but significantly overestimated with MRI. A heterogeneous lesion appearance was observed in several patients. Four patients presented with a well circumscribed hyperintense signal in the vicinity of the apical foramen. The MRI capability of soft tissue characterization may facilitate detailed analysis of periapical lesions. This clinical study confirms the applicability of multi-contrast MRI for the identification of periapical lesions.

  11. Nonlocal Regularized Algebraic Reconstruction Techniques for MRI: An Experimental Study

    Directory of Open Access Journals (Sweden)

    Xin Li

    2013-01-01

    Full Text Available We attempt to revitalize researchers' interest in algebraic reconstruction techniques (ART by expanding their capabilities and demonstrating their potential in speeding up the process of MRI acquisition. Using a continuous-to-discrete model, we experimentally study the application of ART into MRI reconstruction which unifies previous nonuniform-fast-Fourier-transform- (NUFFT- based and gridding-based approaches. Under the framework of ART, we advocate the use of nonlocal regularization techniques which are leveraged from our previous research on modeling photographic images. It is experimentally shown that nonlocal regularization ART (NR-ART can often outperform their local counterparts in terms of both subjective and objective qualities of reconstructed images. On one real-world k-space data set, we find that nonlocal regularization can achieve satisfactory reconstruction from as few as one-third of samples. We also address an issue related to image reconstruction from real-world k-space data but overlooked in the open literature: the consistency of reconstructed images across different resolutions. A resolution-consistent extension of NR-ART is developed and shown to effectively suppress the artifacts arising from frequency extrapolation. Both source codes and experimental results of this work are made fully reproducible.

  12. MRI study on spinal canal content in Western Maharashtrian population

    Directory of Open Access Journals (Sweden)

    Khanapurkar SV, Kulkarni DO, Bahetee BH, Vahane MI

    2014-07-01

    Full Text Available The morphology of the spinal canal content has been studied since the invention of myelography. However, most studies have measured the diameters of the spinal cord only, not the size of the subarachnoid space. The present study complements the current data on the morphology of the spinal contents, and in particular, the spinal subarachnoid space, by analyzing MRI images. Objective: To study morphology of the dural sac, spinal cord & subarachnoid space using MRI. To define the inner geometrical dimensions of spinal canal content that confine the maneuver of an endoscope inserted in cervical spine. 3. To have comprehensive knowledge of the anatomy of cervical spinal canal. Method: Based on MRI images of the spine from 60 normal patients of age between 25-60 years, the dimensions of spinal cord, dural sac & subarachnoid space were measured at mid-vertebral & intervertebral level from C1-C7 vertebrae. The parameters measured were transverse, sagittal diameter of spinal cord & dural sac. The subarachnoid space was measured as anterior, posterior, right, left distance between spinal cord and dura mater. Results: It was found that at each selected transverse level, the subarachnoid space tends to be symmetrical on the right and left sides of the cord, and measures 3.38 mm on an average. However, the anterior and posterior segment, measured on the mid-sagittal plane are generally asymmetric & varies greatly in size ranging 1mm to 6mm with mean 2.57 of anterior & 2.59 of posterior. These measurements match those found in previous studies. The coefficient of variance for the dimensions of the subarachnoid space is as high as 36.16%, while that for the dimensions of the spinal cord (transverse & sagittal are11.08%&13.28%respectively. Conclusion: The findings presented here, expand our knowledge of morphology of spinal canal and show that a thecaloscope must be smaller than 3.38 mm in diameter.

  13. Genome-wide association studies of mri-defined brain infarcts: Meta-analysis from the charge consortium

    NARCIS (Netherlands)

    S. Debette (Stéphanie); J.C. Bis (Joshua); M. Fornage (Myriam); H.A. Schmid (Herbert); M.A. Ikram (Arfan); S. Sigurdsson (Stefan); G. Heiss (Gerardo); M.V. Struchalin (Maksim); A.V. Smith (Albert Vernon); A. van der Lugt (Aad); C. DeCarli (Charles); T. Lumley (Thomas); D.S. Knopman (David); C. Enzinger (Christian); G. Eiriksdottir (Gudny); P.J. Koudstaal (Peter Jan); A.L. DeStefano (Anita); B.M. Psaty (Bruce); C. Dufouil (Carole); D.J. Catellier (Diane); F. Fazekas (Franz); T. Aspelund (Thor); Y.S. Aulchenko (Yurii); A. Beiser (Alexa); J.I. Rotter (Jerome); C. Tzourio (Christophe); D.K. Shibata (Dean); M. Tscherner (Maria); T.B. Harris (Tamara); F. Rivadeneira Ramirez (Fernando); L.D. Atwood (Larry); K. Rice (Kenneth); R.F. Gottesman (Rebecca); M.A. van Buchem (Mark); A.G. Uitterlinden (André); M. Kelly-Hayes (Margaret); M. Cushman (Mary Ann); Y. Zhu (Yicheng); E.A. Boerwinkle (Eric); V. Gudnason (Vilmundur); A. Hofman (Albert); J.R. Romero (Jose Rafael); M.M.B. Breteler (Monique); R. Schmidt (Reinhold); L.J. Launer (Lenore); W.T. Longstreth Jr

    2010-01-01

    textabstractBackground and Purpose-Previous studies examining genetic associations with MRI-defined brain infarct have yielded inconsistent findings. We investigated genetic variation underlying covert MRI infarct in persons without histories of transient ischemic attack or stroke. We performed

  14. Early studies of instant-fMRI for routine examination

    International Nuclear Information System (INIS)

    Sakurai, Yuuki; Harada, Kuniaki; Nagahama, Hiroshi; Akatsuka, Yoshihiro; Shinozaki, Jun

    2010-01-01

    Authors are developing a low-burden, short-time acquisition method of functional magnetic resonance imaging (fMRI) with 3T machine, named ''Instant-fMRI'', aiming for its application to routine examinations, of which results of early studies on identification of the language hemisphere are reported. Subjects were 10 healthy volunteers (8 males, 2 females, mean age 34.2 y, 8 right-handers) and 5 right-hander patients with brain tumor (4 males, 1 female, mean age 50 y). The machine was GE Signa HDx 3.0T ver. 14, using 8 channel head coil. For Instant-fMRI, T1-weighted imaging sequence for mapping was in fast spoiled gradient recalled acquisition in the steady state (fSPGR) mode (scan time: 1 min 44 sec) and fMRI sequence, in GRE-EPI (scan time: 1 min), which thus required only about 3 min in total. Reference was defined to be the anterior-posterior commissure line, to which parallel sections involving centriciput and cerebellum were acquired. Rest (30 sec)-task (shiritori language game, 30 sec) cycle was to be one in instant-fMRI in contrast to three in the conventional fMRI. Volunteers received both instant-fMRI and conventional fMRI and patients, the former alone. Data were analyzed by GE Brain Wave PA. Right and left hemisphere of the left and right hander, respectively, was identified to be activated by instant-fMRI in 9 of 10 volunteers and in all patients, and by the conventional fMRI, in all volunteers. The instant-fMRI can be a useful examination of other brain functions as well as identifying the language field when acquisition parameters for desired diagnostic purpose are optimized. (T.T.)

  15. Longitudinal morphometric MRI study of Alzheimer's disease

    International Nuclear Information System (INIS)

    Ogomori, Koji; Takano, Koichi; Kuwabara, Yasuo; Nakano, Seigo; Nawata, Hideyuki; Yano, Rika; Nishimura, Ryoji; Takita, Masashi

    2009-01-01

    A longitudinal morphometric MRI study of Alzheimer's disease (AD) was conducted to determine the relationship between the progression of the symptoms and the progression of the brain atrophy. The Voxel-based Specific Regional Analysis System for Alzheimer's Disease (VSRAD), developed by Matsuda et al. was used as a method of morphometry to perform the statistical MR image analysis. Thirty-eight patients of AD patients were investigated with VSRAD. These patients were divided into two groups according to the progression of symptoms based on a clinical evaluation. One group was the progress group (20 patients), while the other group was the stable group (18 patients) for comparison. The relationship was investigated between the speed of the symptomatic progression and the change in each VSRAD indicator. Consequently, the entorhinal Z-score and the entorhinal atrophy rate showed a correlation with the speed of the symptomatic progression. The increase of the entorhinal Z-score in the follow-up was larger in the progress group than that in the stable group (0.65/1.28 years in the progress group and 0.05/1.26 years in the stable group.). These results suggest that a rapid symptomatic progression in an AD patient accompanies the rapid progression of atrophy in the entorhinal cortex. (author)

  16. Alternation learning in pathological gamblers: an fMRI Study.

    Science.gov (United States)

    Dannon, Pinhas N; Kushnir, Tammar; Aizer, Anat; Gross-Isseroff, Ruth; Kotler, Moshe; Manor, David

    2011-03-01

    We have previously reported that pathological gamblers have impaired performance on the Stroop color word naming task, go-no-go task and speed accuracy tradeoff performance, tasks used to assess executive function and interference control. The aim of the present neuroimaging study was to explore the relationship between frontal cortex function and gambling severity in pathological gamblers. Functional MRI (fMRI) was used to estimate brain activity of ten male medication-free pathological gamblers during performance of an alternation learning task. Performance of this task has been shown to depend on the function of regions in the frontal cortex. The executive functions needed to perform the alternation learning task were expressed as brain activation in lateral and medial frontal as well as parietal and occipital regions. By correlating the level of local brain activation to task performance, parietal regions and lateral frontal and orbitofrontal regions were demonstrated. A higher score in SOGS was associated with intrusion on the task-specific activation in the left hemisphere, to some extant in parietal regions and even more pronouncedly in left frontal and orbitofrontal regions. Our preliminary data suggests that pathological gambling may be characterized by specific neuro-cognitive changes related to the frontal cortex.

  17. Diagnostic Accuracy of Robot-Guided, Software Based Transperineal MRI/TRUS Fusion Biopsy of the Prostate in a High Risk Population of Previously Biopsy Negative Men

    Directory of Open Access Journals (Sweden)

    Malte Kroenig

    2016-01-01

    Full Text Available Objective. In this study, we compared prostate cancer detection rates between MRI-TRUS fusion targeted and systematic biopsies using a robot-guided, software based transperineal approach. Methods and Patients. 52 patients received a MRIT/TRUS fusion followed by a systematic volume adapted biopsy using the same robot-guided transperineal approach. The primary outcome was the detection rate of clinically significant disease (Gleason grade ≥ 4. Secondary outcomes were detection rate of all cancers, sampling efficiency and utility, and serious adverse event rate. Patients received no antibiotic prophylaxis. Results. From 52 patients, 519 targeted biopsies from 135 lesions and 1561 random biopsies were generated (total n=2080. Overall detection rate of clinically significant PCa was 44.2% (23/52 and 50.0% (26/52 for target and random biopsy, respectively. Sampling efficiency as the median number of cores needed to detect clinically significant prostate cancer was 9 for target (IQR: 6–14.0 and 32 (IQR: 24–32 for random biopsy. The utility as the number of additionally detected clinically significant PCa cases by either strategy was 0% (0/52 for target and 3.9% (2/52 for random biopsy. Conclusions. MRI/TRUS fusion based target biopsy did not show an advantage in the overall detection rate of clinically significant prostate cancer.

  18. Functional MRI in human motor control studies and clinical applications

    International Nuclear Information System (INIS)

    Toma, Keiichiro

    2002-01-01

    Functional magnetic resonance imaging (fMRI) has been a useful tool for the noninvasive mapping of brain function associated with various motor and cognitive tasks. Because fMRI is based on the blood oxygenation level dependent (BOLD) effect, it does not directly record neural activity. With the fMRI technique, distinguishing BOLD signals creased by cortical projection neurons from those created by intracortical neurons appears to be difficult. Two major experimental designs are used in fMRI studies: block designs and event-related designs. Block-designed fMRI presupposes the steady state of regional cerebral blood flow and has been applied to examinations of brain activation caused by tasks requiring sustained or repetitive movements. By contrast, the more recently developed event-related fMRI with time resolution of a few seconds allows the mapping of brain activation associated with a single movement according to the transient aspects of the hemodynamic response. Increasing evidence suggests that multiple motor areas are engaged in a networked manner to execute various motor acts. In order to understand functional brain maps, it is important that one understands sequential and parallel organizations of anatomical connections between multiple motor areas. In fMRI studies of complex motor tasks, elementary parameters such as movement length, force, velocity, acceleration and frequency should be controlled, because inconsistency in those parameters may alter the extent and intensity of motor cortical activation, confounding interpretation of the findings obtained. In addition to initiation of movements, termination of movements plays an important role in the successful achievement of complex movements. Brain areas exclusively related to the termination of movements have been, for the first time, uncovered with an event-related fMRI technique. We propose the application of fMRI to the elucidation of the pathophysiology of movement disorders, particularly dystonia

  19. Functional MRI in human motor control studies and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Toma, Keiichiro [Kyoto Univ. (Japan). Graduate School of Medicine; Nakai, Toshiharu [Inst. of Biomedical Research and Innovation, Kobe (Japan)

    2002-07-01

    Functional magnetic resonance imaging (fMRI) has been a useful tool for the noninvasive mapping of brain function associated with various motor and cognitive tasks. Because fMRI is based on the blood oxygenation level dependent (BOLD) effect, it does not directly record neural activity. With the fMRI technique, distinguishing BOLD signals creased by cortical projection neurons from those created by intracortical neurons appears to be difficult. Two major experimental designs are used in fMRI studies: block designs and event-related designs. Block-designed fMRI presupposes the steady state of regional cerebral blood flow and has been applied to examinations of brain activation caused by tasks requiring sustained or repetitive movements. By contrast, the more recently developed event-related fMRI with time resolution of a few seconds allows the mapping of brain activation associated with a single movement according to the transient aspects of the hemodynamic response. Increasing evidence suggests that multiple motor areas are engaged in a networked manner to execute various motor acts. In order to understand functional brain maps, it is important that one understands sequential and parallel organizations of anatomical connections between multiple motor areas. In fMRI studies of complex motor tasks, elementary parameters such as movement length, force, velocity, acceleration and frequency should be controlled, because inconsistency in those parameters may alter the extent and intensity of motor cortical activation, confounding interpretation of the findings obtained. In addition to initiation of movements, termination of movements plays an important role in the successful achievement of complex movements. Brain areas exclusively related to the termination of movements have been, for the first time, uncovered with an event-related fMRI technique. We propose the application of fMRI to the elucidation of the pathophysiology of movement disorders, particularly dystonia

  20. Study of MRI in stratified viscous plasma configuration

    Science.gov (United States)

    Carlevaro, Nakia; Montani, Giovanni; Renzi, Fabrizio

    2017-02-01

    We analyze the morphology of the magneto-rotational instability (MRI) for a stratified viscous plasma disk configuration in differential rotation, taking into account the so-called corotation theorem for the background profile. In order to select the intrinsic Alfvénic nature of MRI, we deal with an incompressible plasma and we adopt a formulation of the local perturbation analysis based on the use of the magnetic flux function as a dynamical variable. Our study outlines, as consequence of the corotation condition, a marked asymmetry of the MRI with respect to the equatorial plane, particularly evident in a complete damping of the instability over a positive critical height on the equatorial plane. We also emphasize how such a feature is already present (although less pronounced) even in the ideal case, restoring a dependence of the MRI on the stratified morphology of the gravitational field.

  1. Assessment of colonic transit time using MRI: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Buhmann, Sonja; Reiser, Maximilian F.; Lienemann, Andreas [Ludwig-Maximilians-University, Department of Clinical Radiology, Campus Grosshadern, Munich (Germany); Kirchhoff, Chlodwig; Ladurner, Roland; Mussack, Thomas [Ludwig-Maximilians-University, Department of Surgery and Traumatology, Campus Innenstadt, Munich (Germany)

    2007-03-15

    The aim of this pilot study was to evaluate a new, non-invasive examination method using MRI for the quantification of the colonic transit time after oral administration of gadolinium-saline solution filled capsules. Healthy volunteers without previous or acute symptoms of gastrointestinal disorders were enrolled. After a 3-day diet for the standardization of gastrocolonic content the volunteers swallowed five Gd-DTPA/saline 0.9%-filledcapsules. Seven different concentrations of Gd-DTPA/saline 0.9% solution between 1:0 and 0:1 were tested in a dilution series. Following ingestion of capsules, coronal Flash T1 and True Fisp sequences using a 1.5 Tesla system were obtained at 0 h, 3 h, 6 h, 12 h, 24 h, 36 h and 60 h. Sequences were analyzed by two independent experts for locating the capsules. Overall colonic transit time was separately analyzed for both genders. Fifteen healthy volunteers (7 females, 8 males; mean age 34{+-}13 years) were enrolled. The phantom study provided the best contrast in both the T1-and T2-weighted sequences defining a ratio of 1:10 for Gd-DTPA/saline 0.9% solution. The mean transit time accounted for 41{+-}9 h in women and for 31{+-}10 h in men. MRI is an adequate method for the assessment of colonic transit time offering the advantages of no exposure to radiation, short examination time, possible dynamic evaluation of the transit and the practicability in terms of a future adoption to clinical routine. (orig.)

  2. Assessment of colonic transit time using MRI: a feasibility study

    International Nuclear Information System (INIS)

    Buhmann, Sonja; Reiser, Maximilian F.; Lienemann, Andreas; Kirchhoff, Chlodwig; Ladurner, Roland; Mussack, Thomas

    2007-01-01

    The aim of this pilot study was to evaluate a new, non-invasive examination method using MRI for the quantification of the colonic transit time after oral administration of gadolinium-saline solution filled capsules. Healthy volunteers without previous or acute symptoms of gastrointestinal disorders were enrolled. After a 3-day diet for the standardization of gastrocolonic content the volunteers swallowed five Gd-DTPA/saline 0.9%-filledcapsules. Seven different concentrations of Gd-DTPA/saline 0.9% solution between 1:0 and 0:1 were tested in a dilution series. Following ingestion of capsules, coronal Flash T1 and True Fisp sequences using a 1.5 Tesla system were obtained at 0 h, 3 h, 6 h, 12 h, 24 h, 36 h and 60 h. Sequences were analyzed by two independent experts for locating the capsules. Overall colonic transit time was separately analyzed for both genders. Fifteen healthy volunteers (7 females, 8 males; mean age 34±13 years) were enrolled. The phantom study provided the best contrast in both the T1-and T2-weighted sequences defining a ratio of 1:10 for Gd-DTPA/saline 0.9% solution. The mean transit time accounted for 41±9 h in women and for 31±10 h in men. MRI is an adequate method for the assessment of colonic transit time offering the advantages of no exposure to radiation, short examination time, possible dynamic evaluation of the transit and the practicability in terms of a future adoption to clinical routine. (orig.)

  3. MRI study on urinary abnormalities of fetus

    International Nuclear Information System (INIS)

    Liu Ming; Zhang Yuzhen; Wang Qiuyan; Zhang Zhongyang; Li Yuhua

    2007-01-01

    Objective: To illustrate the important complemental function of MRI in dignosing the urinary abnormalities of the fetus by analyzing MR features. Methods: MRI findings in 34 fetal urinary abnormalities were retrospectively analyzed. Results: Upper urinary tract dilatation was found in 12 cases: one case presented obstructed right renal dysplasia and was on the follow-up, postnatal MR imaging proved the duplex anomaly in one case, one case showed left PUJO on postnatal US imaging and prepared to surgery, 7 cases were normal on postnatal US imaging, 2 cases were lost to follow up. Bilateral urinary anomalies were found in 7 cases: Muhicystic renal dysplasia (n=3), Combined horseshoe kidney in 2 fetuses and bilateral renal aplasia in one case. Bilateral renal dysplasia was diagnosed in 2 cases, one was still bom and proved by autopsy and the other was lost to follow up. The case of bilateral renal agenesis displayed the appearance of sirenomelia on general specimen. The case of right renal agenesis associated contralateral kidney dyspalsia (n=1) was lost to follow up. MR imaging showed low signal intensity of lung and oligohydramnios in the bilateral anomalies. Unilateral urinary anomalies was found in 15 cases, including 9 cases of unilateral renal dysplasia. Two fetuses were aborted and 3 fetuses were proved with postnatal US or MR. One was lost to follow up; 3 cases were on the follow-up. There were 4 cases of unilateral renal agenesis, two fetuses were aborted and 2 fetuses were proved with postnatal US or MR imaging. The case of ectopic kidney was proved with postnatal US imaging. One case of urachal cyst was aborted without autopsy. In the unilateral anomalies, the volume of amniotic fluid was normal, and the fetal lung presented homogenious high signal intensity. Conclusion: As a complemental method, MRI is of great value in displaying and dignosing the urinary abnormalities of fetus. (authors)

  4. 40 CFR 152.93 - Citation of a previously submitted valid study.

    Science.gov (United States)

    2010-07-01

    ... Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An applicant may demonstrate compliance for a data requirement by citing a valid study previously submitted to the Agency. The... the original data submitter, the applicant may cite the study only in accordance with paragraphs (b...

  5. Brain activation studies with PET and functional MRI

    Energy Technology Data Exchange (ETDEWEB)

    Yonekura, Yoshiharu [Fukui Medical Univ., Matsuoka (Japan). Biomedical Imaging Research Center; Sadato, Norihiro [Okazaki National Research Inst., Aichi (Japan). National Inst. for Physiological Sciences

    2002-01-01

    Application of PET and functional MRI in brain activation studies is reviewed. 3D-PET images obtained repeatedly after intravenous injection of about 370 MBq of H{sub 2}{sup 15}O can detect a faint blood flow change in the brain. Functional MRI can also detect the blood flow change in the brain due to blood oxygen level-dependent effect. Echo-planar imaging is popular in MRI with 1.5 or 3 T. Images are analyzed by statistical parametric mapping with correction of cerebral regions, anatomical normalization and statistics. PET data give the blood flow change by the H{sub 2}{sup 15}O incorporation into the brain and MRI data, by the scarce tissue oxygen consumption despite the change. Actual images during the cognition task-performance and of frequent artifacts are given. PET is suitable for studies of brain functions like sensibility and emotion and functional MRI, like cortex functions and clinical practices in identification of functional regions prior to surgery and evaluation of functional recovery of damaged brain. (K.H.)

  6. Brain activation studies with PET and functional MRI

    International Nuclear Information System (INIS)

    Yonekura, Yoshiharu; Sadato, Norihiro

    2002-01-01

    Application of PET and functional MRI in brain activation studies is reviewed. 3D-PET images obtained repeatedly after intravenous injection of about 370 MBq of H 2 15 O can detect a faint blood flow change in the brain. Functional MRI can also detect the blood flow change in the brain due to blood oxygen level-dependent effect. Echo-planar imaging is popular in MRI with 1.5 or 3 T. Images are analyzed by statistical parametric mapping with correction of cerebral regions, anatomical normalization and statistics. PET data give the blood flow change by the H 2 15 O incorporation into the brain and MRI data, by the scarce tissue oxygen consumption despite the change. Actual images during the cognition task-performance and of frequent artifacts are given. PET is suitable for studies of brain functions like sensibility and emotion and functional MRI, like cortex functions and clinical practices in identification of functional regions prior to surgery and evaluation of functional recovery of damaged brain. (K.H.)

  7. The cerebral intravascular enhancement sign is not specific: a contrast-enhanced MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Bakshi, R.; Kinkel, W.R.; Bates, V.E.; Mechtler, L.L.; Kinkel, P.R. [Lucy Dent Imaging Center, University at Buffalo, NY (United States)

    1999-02-01

    The intravascular enhancement (IVE) sign, also known as the ``arterial enhancement sign``, is an abnormal finding in the brain on contrast-enhanced MRI studies. IVE has been described in arterial cerebrovascular disorders, most commonly in acute or subacute arterial ischemic infarcts. However, the specificity of this sign has not been established. We describe four patients with disorders other than arterial strokes in whom gadolinium-enhanced high-field (1.5 T) MRI suggested IVE. The conditions were herpes simplex viral encephalitis, idiopathic cerebellitis, pneumococcal meningitis, and superior sagittal sinus thrombosis with venous infarction. IVE in these cases may be due to multiple factors, including arterial, venous, perivascular, and leptomeningeal or sulcal contrast medium accumulation. Our observations suggest that arterial ischemia, previously described as the cardinal cause of IVE, probably does not explain all instances, and urge caution in interpreting this sign as a specific MRI manifestation of acute arterial infarction or ischemia. (orig.) With 4 figs., 1 tab., 44 refs.

  8. Effective orbital volume and eyeball position: an MRI study.

    Science.gov (United States)

    Detorakis, Efstathios T; Drakonaki, Eleni; Papadaki, Efrosini; Pallikaris, Ioannis G; Tsilimbaris, Miltiadis K

    2010-10-01

    Previous studies have examined factors affecting the position of the eyeball to the orbit. This study examined the role of effective orbital volume (EOV), defined as the difference between orbital and eyeball volume, as a determinant of eyeball position, using MRI scans. Forty-six patients were recruited from the Department of Ophthalmology of the University Hospital of Heraklion, Crete Greece. Patients with a history of orbital disease were excluded. Distances between eyeball poles and orbital landmarks were measured in T1 weighted transverse, sagittal and coronal orbital images. The protrusion of the eyeball in the sagittal and transverse planes was recorded. The volume of the eyeball and bony orbit, the EOV, the volume of the extraocular muscles as well as clinical information (age, gender, Hertel exophthalmometry) were also recorded. EOV was significantly associated with orbital volume but not with eyeball volume. EOV was also significantly associated with transverse and sagittal globe protrusions. Females displayed significantly lower orbital and eyeball volumes as well as EOV than males but higher transverse globe protrusion than males. Variations in EOV are associated with orbital volume rather than with eyeball volume. EOV is associated with globe protrusion and may be taken into account in the planning of various procedures, including orbital decompression, treatment of enophthalmos or the size of orbital implants following enucleation.

  9. Summary of Previous Chamber or Controlled Anthrax Studies and Recommendations for Possible Additional Studies

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.; Amidan, Brett G.; Morrow, Jayne B.

    2010-12-29

    This report and an associated Excel file(a) summarizes the investigations and results of previous chamber and controlled studies(b) to characterize the performance of methods for collecting, storing and/or transporting, extracting, and analyzing samples from surfaces contaminated by Bacillus anthracis (BA) or related simulants. This report and the Excel are the joint work of the Pacific Northwest National Laboratory (PNNL) and the National Institute of Standards and Technology (NIST) for the Department of Homeland Security, Science and Technology Directorate. The report was originally released as PNNL-SA-69338, Rev. 0 in November 2009 with limited distribution, but was subsequently cleared for release with unlimited distribution in this Rev. 1. Only minor changes were made to Rev. 0 to yield Rev. 1. A more substantial update (including summarizing data from other studies and more condensed summary tables of data) is underway

  10. Fingersomatotopy in area 3b: an fMRI-study

    Directory of Open Access Journals (Sweden)

    Rosén Birgitta

    2004-08-01

    Full Text Available Abstract Background The primary sensory cortex (S1 in the postcentral gyrus is comprised of four areas that each contain a body map, where the representation of the hand is located with the thumb most laterally, anteriorly and inferiorly and the little finger most medially, posteriorly and superiorly. Previous studies on somatotopy using functional MRI have either used low field strength, have included a small number of subjects or failed to attribute activations to any area within S1. In the present study we included twenty subjects, who were investigated at 3 Tesla (T. We focused specifically on Brodmann area 3b, which neurons have discrete receptive fields with a potentially more clearcut somatotopic organisation. The spatial distribution for all fingers' peak activation was determined and group as well as individual analysis was performed. Results Activation maps from 18 subjects were of adequate quality; in 17 subjects activations were present for all fingers and these data were further analysed. In the group analysis the thumb was located most laterally, anteriorly and inferiorly with the other fingers sequentially positioned more medially, posteriorly and superiorly. At the individual level this somatotopic relationship was present for the thumb and little finger, with a higher variability for the fingers in between. The Euclidian distance between the first and fifth finger was 17.2 mm, between the first and second finger 10.6 mm and between the remaining fingers on average 6.3 mm. Conclusion Results from the group analysis, that is both the location of the fingers and the Euclidian distances, are well comparable to results from previous studies using a wide range of modalities. On the subject level the spatial localisation of the fingers showed a less stringent somatotopic order so that the location of a finger in a single subject cannot be predicted from the group result.

  11. The efficacy of dynamic MRI in assessing a cervical myelopathy; A retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, Tetsuya; Yamada, Tomonori; Okumura, Yoshiya; Hashimoto, Hiroshi; Hiramatsu, Kenichiro; Tsunoda, Shigeru; Sakaki, Toshisuke; Iwasaki, Satoru (Nara Medical Univ., Kashihara (Japan))

    1994-01-01

    There are problems that are unresolved with regard to the treatment of cases presenting a post-taumatic cervical myelopathy, such as when the surgical indications are not clearly evidence and the proper timing of this surgery. In this regard, the authors have used dynamic MRI to retrospectively analyze the cervical spine of 24 previously treated dynamic MRI cases presenting a subacute myelopathy to determine the efficacy of dynamic MRI as a method of treatment. Dynamic MRI analysis protocol was as follows. For the MR imagings, each patient was placed supine with the neck in the neutral position, after which the neck was set in the extended position. Dynamic changes between the neutral position and extended position images were analyzed by focusing on the following two point: (1) the narrowing of the subarachnoid space in the T2-weighted images and (2) evidence of cord compression in the T1-weighted images. Twelve cases out of 24 were treated conservatively because of a gradual improvement in their myelopathic symptoms. The other 12 cases were treated surgically, because of no improvement in their residual myelopathic symptoms at the time when the dynamic MRI had been performed. In the majority of cases in the surgical group, the narrowing of the subarachnoid space and spinal cord compression were hightened on neck extension, whereas in the conservative group, such findings were minimal. Dynamic MRI also more clearly visualized multiple lesions and the direction of the cord compression. These findings thus provided more detailed information to plan the surgical approach and to estimate the amount of surgical decompression needed. Based on the results of this retrospective study, we thus concluded that surgical treatment appears to benefit subacute cases who show no improvement in their residual myelopathic symptoms and whose dynamic MRI results also demonstrate an increased narrowing of subarachnoid space and a heightened spinal cord compression. (author).

  12. MRI Compatibility of Robot Actuation Techniques – A Comparative Study

    Science.gov (United States)

    Fischer, Gregory S.; Krieger, Axel; Iordachita, Iulian; Csoma, Csaba; Whitcomb, Louis L.; Fichtinger, Gabor

    2010-01-01

    This paper reports an experimental evaluation of the following three different MRI-compatible actuators: a Shinsei ultrasonic motor, a Nanomotion ultrasonic motor and a pneumatic cylinder actuator. We report the results of a study comparing the effect of these actuators on the signal to noise ratio (SNR) of MRI images under a variety of experimental conditions. Evaluation was performed with the controller inside and outside the scanner room and with both 1.5T and 3T MRI scanners. Pneumatic cylinders function with no loss of SNR with controller both inside and outside of the scanner room. The Nanomotion motor performs with moderate loss of SNR when moving during imaging. The Shinsei is unsuitable for motion during imaging. All may be used when motion is appropriately interleaved with imaging cycles. PMID:18982643

  13. Functional MRI studies of the neural mechanisms of human brain attentional networks

    International Nuclear Information System (INIS)

    Hao Jing; Li Kuncheng; Chen Qi; Wang Yan; Peng Xiaozhe; Zhou Xiaolin

    2005-01-01

    Objective: To identify the neural mechanisms of the anterior attention network (AAN) and posterior attention network (PAN) , investigate the possible interaction between them with event-related functional MRI(ER-fMRI). Methods: Eight right-handed healthy volunteers participated in the experiment designed with inhibition of return in visual orienting and Stroop color-word interference effect. The fMRI data were collected on Siemens 1.5 T Sonata MRI systems and analyzed by AFNI to generate the activation map. Results: The data sets from 6 of 8 subjects were used in the study. The functional localizations of the Stroop and IOR, which manifest the function of the AAN and PAN respectively, were consistent with previous imaging researches. On cued locations, left inferior parietal lobule (IPL), area MT/V5, right dorsolateral prefrontal cortex (DLPFC) and left anterior cingulated cortex (ACC) were significantly activated. On uncued locations, right superior parietal lobule (SPL) and bilateral area MT/V5 were significantly activated. Conclusion: The AAN exerts control over the PAN, while its function can be in turn modulated by the PAN. There are interaction between the AAN and PAN. In addition, it is also proved that ER-fMRI is a feasible method to revise preexisting cognitive model and theory. (authors)

  14. The G-spot: an observational MRI pilot study.

    Science.gov (United States)

    Maratos, Y K; Gombergh, R; Cornier, E; Minart, J P; Amoretti, N; Mpotsaris, A

    2016-08-01

    To identify a G-spot complex (GSC) in vivo in MRI examinations at 1.5 Tesla field strength. Observational study. Single centre. Twenty-one consecutive patients (January-March 2014). Imaging analysis of routine imaging protocols for usual medical indications with and without concomitant opacification of the vaginal cavity with inert ultrasound gel. The gel distends the otherwise collapsed vaginal walls, allowing for an improved discrimination of anatomic features. The macroscopic and histological results recently derived from the dissections of fresh cadavers by Ostrzenski et al. were translated into imaging characteristics to be expected in the respective MRI sequences (e.g. T1- and T2-weighted) in search of an in vivo correlate of the GSC. Age, menopause status, medical indication and diagnosis were co-variables. To analyse primarily whether MRI imaging is able to depict a distinct morphological entity in vivo matching the GSC, based on anatomical descriptions published recently. The elaboration of an appropriate MRI-imaging protocol was a secondary aim. A total of 21 studies were obtained. A GSC was identified within the anterior vaginal wall in 13/21 patients (62%). In all, 10/21 (48%) had vaginal gel opacification. We identified a GSC in 10/10 patients (100%) with opacification in all three planes of the T2 images. This was only true for 3/11 cases (27%) without opacification. There is evidence for an in vivo morphological correlate to the postmortem anatomical findings of a GSC described by Ostrzenski et al.; its visibility in MRI imaging can be significantly improved with vaginal opacification by ultrasound gel. Identification of G-spot by MRI with vaginal gel-opacification in 13/21 patients. © 2016 Royal College of Obstetricians and Gynaecologists.

  15. Studies on hippocampal sclerosis by 1H MRS and MRI

    International Nuclear Information System (INIS)

    Qi Jing; Du Xiangke; Luan Guoming; Wang Dehang

    2000-01-01

    Objective: To determine the relative utility of 1 H MRS and MRI for pre-surgical diagnosis of hippocampal sclerosis by the study on metabolic abnormalities and anatomical alterations in the brain of patients with temporal lobe epilepsy (TLE). Methods: 1 H MRS and MRI were performed on 8 patients with pathologically confirmed hippocampal sclerosis and 8 healthy volunteers on 2.0 T 1 H MRS/MRI system. The values of NAA, Cr and Cho were calculated by integration of their peaks and the ratios of NAA/Cr, NAA/(Cr + Cho), and Cho/Cr were measured. The volumes of both hippocampal formations in every case were observed and the differences of hippocampal formation (DHF) were analyzed. Results: The ratios of NAA/Cr, NAA/(Cr + Cho), and Cho/Cr in ipsilateral side were 0.55, 1.77 and 1.38, and in control subjects were 0.77, 1.38 and 1.06 separately. The ratios of NAA/Cr and NAA/(Cr + Cho) were decreased on ipsilateral side (t = 2.15, 4.83 separately, P 1 H MRS and MRI, seven of eight cases could be lateralized. Conclusion: 1 H MRS is sensitive to the diagnosis of neuron abnormality and coincident well with the pathological results 1 H MRS and MRI correctly lateralize most patients with hippocampal sclerosis and complement each other in final lateralization. The combination of 1 H MRS and MRI can provide useful information for pre-surgical diagnosis of hippocampal sclerosis

  16. Mixed-effects and fMRI studies

    DEFF Research Database (Denmark)

    Friston, K.J; Stephan, K.E; Ellegaard Lund, Torben

    2005-01-01

    This note concerns mixed-effect (MFX) analyses in multisession functional magnetic resonance imaging (fMRI) studies. It clarifies the relationship between mixed-effect analyses and the two-stage 'summary statistics' procedure (Holmes, A.P., Friston, K.J., 1998. Generalisability, random effects...

  17. Matched cohort study of external cephalic version in women with previous cesarean delivery.

    Science.gov (United States)

    Keepanasseril, Anish; Anand, Keerthana; Soundara Raghavan, Subrahmanian

    2017-07-01

    To evaluate the efficacy and safety of external cephalic version (ECV) among women with previous cesarean delivery. A retrospective study was conducted using data for women with previous cesarean delivery and breech presentation who underwent ECV at or after 36 weeks of pregnancy during 2011-2016. For every case, two multiparous women without previous cesarean delivery who underwent ECV and were matched for age and pregnancy duration were included. Characteristics and outcomes were compared between groups. ECV was successful for 32 (84.2%) of 38 women with previous cesarean delivery and 62 (81.6%) in the control group (P=0.728). Multivariate regression analysis confirmed that previous cesarean was not associated with ECV success (odds ratio 1.89, 95% confidence interval 0.19-18.47; P=0.244). Successful vaginal delivery after successful ECV was reported for 19 (59.4%) women in the previous cesarean delivery group and 52 (83.9%) in the control group (P<0.001). No ECV-associated complications occurred in women with previous cesarean delivery. To avoid a repeat cesarean delivery, ECV can be offered to women with breech presentation and previous cesarean delivery who are otherwise eligible for a trial of labor. © 2017 International Federation of Gynecology and Obstetrics.

  18. Hydrodynamic study of syringomyelia by MRI and intraoperative ultrasonography

    International Nuclear Information System (INIS)

    Moritake, Kouzo; Takaya, Mikio; Minamikawa, Jun; Ishikawa, Masatsune; Kikuchi, Haruhiko; Minami, Shunsuke

    1989-01-01

    Syringomyelic cavities were studied with magnetic resonance imaging (MRI) in eleven patients with special reference to the hemodynamic contribution to the pathogenesis of syringomyelia. They were also studied intraoperatively with ultrasonography (USG) in five patients. Syrinx cavities combined with lumbosacral lipomyelomeningocele or with spinal stenosis did not present a flow-void phenomenon reflecting pulsatile movements of syrinx fluid. On serial MRI study in those the patients, enlargement of the syrinx cavity was not observed. Syrinx cavities occupying the caudal part of the spinal cord did not develop either. These cases were not treated surgically but followed conservatively. On the other hand, the flow-void sign in the syrinx cavities was present on MRI in patients who also had Chiari type I or type II malformations. They were treated with a syringo-subarachnoid shunt. In these cases, intraoperative USG disclosed marked fluctuation of syrinx cavity size synchronous with the motions of pulmonary ventilation. In all of them, clinical signs and symptoms improved postoperatively to various degrees. These results suggest that both the flow-void sign in the syrinx cavity on MRI and marked fluctaution of cavity size on intraoperative USG are indications for the shunt operation and support William's revised theory (1987). Fluctuation of cystic cavity size synchronous with ventilation suggests that venous pressure in the spinal subarachnoid space contributes to the pathogenesis of syringomyelic cavities. Further analysis of the fluctuation of cystic cavities by video monitoring will provide further information on the etiology and other clinical problems of syringomyelia. (author)

  19. MRI study in spondyloepiphyseal dysplasia tarda with progressive arthropathy

    International Nuclear Information System (INIS)

    Tan Lihua; Liao Eryuan; Xiao Enhua; Ma Cong; Du Wanping; Li Jian

    2005-01-01

    Objective: To study the MRI features and the cartilaginous pathology of the spondyloepiphyseal dysplasia tarda with progressive arthropathy (SEDT-PA). Methods: MRI of spine, bilateral hips, and knees was taken in 2 cases with clinically and radiographically proven SEDT-PA, who were sister and brother and whose parents were healthy and not inbreeding. The sister's femoral heads were resected bilaterally and the tissues were used for pathological study. Results: MRI showed that the kyphosis and lateroflexion of the spine, and the degenerative signs of the intervertebral discs became more evident along with the growth of the patients. The anterior annular secondary ossification centers of cartilaginous epiphyses of some vertebral bodies didn't appear. So the affected vertebral bodies were like 'inverted vase' or the end p late like 'steps'. Bilateral acetabular cartilage and medial epicondylian cartilaginous epiphyses of the femurs in the young brother showed regional high signal intensity on coronal fat-saturated proton density weighted MR images and degenerative signs on the elder sister. The regional hyperplasia and hypogenesis of the femoral head cartilage could be seen by microscope. Conclusion: There are characteristic features on MRI in SEDT-PA and this is due to the regional hyperplasia and hypogenesis of the cartilage pathologically. (authors)

  20. Anatomic MRI study of a small muscle: the masseter

    International Nuclear Information System (INIS)

    Dheyriat, A.; Lissac, M.; Sappey-Marinier, D.; Bonmartin, A.

    1997-01-01

    Magnetic resonance imaging (MRI) provides functional information in an anatomic presentation allowing to distinguish soft tissues with high sensitivity. The goal of this study was to investigate the normal anatomy of the major masticatory muscle, the masseter, both at rest or during contraction by using three dimensional (3D) MRI. Eighteen subjects aged from 19 to 28 years, all in good health, were studied. Several experiments were first realized on phantoms to test the 3D-MRI technique. After reconstruction and segmentation processing, 3D acquisition, enabled obtaining data on the masseter anatomy. The normal anatomical position of the masseter was reported to the skin plan as the mean internal distance (7.9±0.42 mm) and external distance (15.2±0.41 mm). While there was no difference between internal distance, for sex or side, the external distance was significantly (p = 0.02) shorter in male (7.7±0.5 mm) than in female (8.8±0.4 mm) for both sides. The mean volume for all subjects and both sides (20.3±1.1 cm 3 ) did not change significantly between rest and exercise. The masseter volume was significantly (p 3 ) than in female (16.4±3.6 cm 3 ) groups. These physiological references may be useful for further MRI investigations of masticatory system pathologies. (authors)

  1. Cortical control of gait in healthy humans: an fMRI study

    International Nuclear Information System (INIS)

    ChiHong, Wang; YauYau, Wai; BoCheng, Kuo; Yei-Yu, Yeh; JiunJie Wang

    2008-01-01

    This study examined the cortical control of gait in healthy humans using functional magnetic resonance imaging (fMRI). Two block-designed fMRI sessions were conducted during motor imagery of a locomotor-related task. Subjects watched a video clip that showed an actor standing and walking in an egocentric perspective. In a control session, additional fMRI images were collected when participants observed a video clip of the clutch movement of a right hand. In keeping with previous studies using SPECT and NIRS, we detected activation in many motor-related areas including supplementary motor area, bilateral precentral gyrus, left dorsal premotor cortex, and cingulate motor area. Smaller additional activations were observed in the bilateral precuneus, left thalamus, and part of right putamen. Based on these findings, we propose a novel paradigm to study the cortical control of gait in healthy humans using fMRI. Specifically, the task used in this study - involving both mirror neurons and mental imagery - provides a new feasible model to be used in functional neuroimaging studies in this area of research. (author)

  2. STUDY OF POSTERIOR FOSSA TUMORS BY HIGH RESOLUTION MRI

    Directory of Open Access Journals (Sweden)

    Sree Hari

    2016-01-01

    Full Text Available INTRODUCTION Magnetic Resonance Imaging (MRI is the imaging modality used for the assessment of infratentorial neoplasms. Although Computed Tomography (CT provides better demonstration of small or subtle calcifications within tumors. OBJECTIVES Study is done to assess the potential of MRI in characterisation of different tumors in posterior fossa by evaluating various unenhanced and gadolinium enhanced sequences and to compare high resolution FSE MRI sequences with routine FSE MRI sequences in diagnosing posterior fossa brain tumors. Also correlate findings on Magnetic Resonance Imaging with Pathological diagnosis. MATERIALS AND METHODS A total of 52 patients were diagnosed by CT brain as having posterior fossa brain for a year of 2 years were included in the study. In all studies MR imaging was performed with a clinical 1.5 T system (General electrical medical systems. A dedicated phased-array coil was used. RESULTS The age group ranged from 1 year to 60 years, majority were between 1 to 20 years (39%. Slight male preponderance was seen (males 29, females 23. Commonest tumor encountered in our study was vestibular schwannoma. DWI alone can differentiate different pediatric posterior fossa brain tumors. One case of pilocytic astrocytoma showed solid lesion instead of typical cystic lesion with mural nodule. One case AT-RT showed 2 lesions one in cerebrum, one in CP angle. Common feature being intra-axial lesion involving cerebellum. MRI was able to predict diagnosis in 50 of the 52 tumors. CONCLUSION Magnetic Resonance Imaging was found to be a highly sensitive imaging procedure and method of choice for posterior fossa brain tumors.

  3. Assessment of abstract reasoning abilities in alcohol-dependent subjects: an fMRI study

    International Nuclear Information System (INIS)

    Bagga, Deepika; Singh, Namita; Singh, Sadhana; Modi, Shilpi; Kumar, Pawan; Bhattacharya, D.; Garg, Mohan L.; Khushu, Subash

    2014-01-01

    Chronic alcohol abuse has been traditionally associated with impaired cognitive abilities. The deficits are most evident in higher order cognitive functions, such as abstract reasoning, problem solving and visuospatial processing. The present study sought to increase current understanding of the neuropsychological basis of poor abstract reasoning abilities in alcohol-dependent subjects using functional magnetic resonance imaging (fMRI). An abstract reasoning task-based fMRI study was carried out on alcohol-dependent subjects (n = 18) and healthy controls (n = 18) to examine neural activation pattern. The study was carried out using a 3-T whole-body magnetic resonance scanner. Preprocessing and post processing was performed using SPM 8 software. Behavioral data indicated that alcohol-dependent subjects took more time than controls for performing the task but there was no significant difference in their response accuracy. Analysis of the fMRI data indicated that for solving abstract reasoning-based problems, alcohol-dependent subjects showed enhanced right frontoparietal neural activation involving inferior frontal gyrus, post central gyrus, superior parietal lobule, and occipito-temporal gyrus. The extensive activation observed in alcohol dependents as compared to controls suggests that alcohol dependents recruit additional brain areas to meet the behavioral demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting decreased neural efficiency of relevant brain networks or compensatory mechanisms for the execution of task for showing an equivalent performance. (orig.)

  4. Assessment of abstract reasoning abilities in alcohol-dependent subjects: an fMRI study

    Energy Technology Data Exchange (ETDEWEB)

    Bagga, Deepika; Singh, Namita; Singh, Sadhana; Modi, Shilpi; Kumar, Pawan [Institute of Nuclear Medicine and Allied Sciences (INMAS), NMR Research Centre, Delhi (India); Bhattacharya, D. [Base Hospital, Department of Psychiatry, Delhi Cantt (India); Garg, Mohan L. [Panjab University, Department of Biophysics, Chandigarh (India); Khushu, Subash [Institute of Nuclear Medicine and Allied Sciences (INMAS), NMR Research Centre, Delhi (India); INMAS, DRDO, NMR Research Centre, Delhi (India)

    2014-01-15

    Chronic alcohol abuse has been traditionally associated with impaired cognitive abilities. The deficits are most evident in higher order cognitive functions, such as abstract reasoning, problem solving and visuospatial processing. The present study sought to increase current understanding of the neuropsychological basis of poor abstract reasoning abilities in alcohol-dependent subjects using functional magnetic resonance imaging (fMRI). An abstract reasoning task-based fMRI study was carried out on alcohol-dependent subjects (n = 18) and healthy controls (n = 18) to examine neural activation pattern. The study was carried out using a 3-T whole-body magnetic resonance scanner. Preprocessing and post processing was performed using SPM 8 software. Behavioral data indicated that alcohol-dependent subjects took more time than controls for performing the task but there was no significant difference in their response accuracy. Analysis of the fMRI data indicated that for solving abstract reasoning-based problems, alcohol-dependent subjects showed enhanced right frontoparietal neural activation involving inferior frontal gyrus, post central gyrus, superior parietal lobule, and occipito-temporal gyrus. The extensive activation observed in alcohol dependents as compared to controls suggests that alcohol dependents recruit additional brain areas to meet the behavioral demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting decreased neural efficiency of relevant brain networks or compensatory mechanisms for the execution of task for showing an equivalent performance. (orig.)

  5. Cortical language activation in aphasia: a functional MRI study

    International Nuclear Information System (INIS)

    Xu Xiaojun; Zhang Minming; Shang Desheng; Wang Qidong; Luo Benyan

    2004-01-01

    Objective: To investigate the differences of the underlying neural basis of language processing between normal subjects and aphasics, and to study the feasibility for functional magnetic resonance imaging (fMRI) in examining the cortical language activation in clinical aphasics. Methods: fMRI was used to map language network in 6 normal subjects and 3 patients with aphasia who were in the stage of recovery from acute stroke. The participants performed word generation task during fMRI scanning, which measured the signal changes associated with regional neural activity induced by the task. These signal changes were processed to statistically generate the activation map that represented the language area. Results: In normal subjects, a distributed language network was activated. Activations were present in the frontal, temporal, parietal and occipital regions in normal group. In the patient group, however, no activation was showed in the left inferior frontal gyrus whether or not the patient had lesion in the left frontal lobe. Two patients showed activations in some right hemisphere regions where no activation appeared in normal subjects. Conclusion: The remote effect of focal lesion and functional redistribution or reorganization was found in aphasic patients. fMRI was useful in evaluating the language function in aphasic patients. (authors)

  6. MR-Imaging of teeth and periodontal apparatus: an experimental study comparing high-resolution MRI with MDCT and CBCT

    International Nuclear Information System (INIS)

    Gaudino, Chiara; Csernus, Reka; Pham, Mirko; Bendszus, Martin; Rohde, Stefan; Cosgarea, Raluca; Kim, Ti-Sun; Heiland, Sabine; Beomonte Zobel, Bruno

    2011-01-01

    The aim of this study was (1) to assess the ability of magnetic resonance imaging (MRI) to visualize dental and periodontal structures and (2) to compare findings with multidetector computed tomography (MDCT) and cone beam CT (CBCT). Four porcine mandibles were examined with (1) 3T-MRI, (2) MDCT and (3) CBCT. Two observers independently reviewed MR, MDCT and CBCT images and assessed image quality of different dental and periodontal structures. To assess quantitatively the accuracy of the different imaging technique, both observers measured burr holes, previously drilled in the mandibles. Dental structures, e.g. teeth roots, pulpa chamber and dentin, were imaged accurately with all imaging sources. Periodontal space and cortical/trabecular bone were better visualized by MRI (p < 0.001). MRI could excellently display the lamina dura, not detectable with MDCT and only inconstant visible with CBCT (p < 0.001). Burr hole measurements were highly precise with all imaging techniques. This experimental study shows the diagnostic feasibility of MRI in visualization of teeth and periodontal anatomy. Detection of periodontal structures was significantly better with MRI than with MDCT or CBCT. Prospective trials have to evaluate further the potential benefit of MRI in a clinical setting. (orig.)

  7. MR-Imaging of teeth and periodontal apparatus: an experimental study comparing high-resolution MRI with MDCT and CBCT

    Energy Technology Data Exchange (ETDEWEB)

    Gaudino, Chiara; Csernus, Reka; Pham, Mirko; Bendszus, Martin; Rohde, Stefan [University Hospital Heidelberg, Department of Neuroradiology, Heidelberg (Germany); Cosgarea, Raluca; Kim, Ti-Sun [University Hospital Heidelberg, Department of Periodontology, Heidelberg (Germany); Heiland, Sabine [University Hospital Heidelberg, Section of Experimental Radiology, Heidelberg (Germany); Beomonte Zobel, Bruno [University Campus Bio-Medico of Rome, Department of Radiology, Interdisciplinary Center for Biomedical Research, Rome (Italy)

    2011-12-15

    The aim of this study was (1) to assess the ability of magnetic resonance imaging (MRI) to visualize dental and periodontal structures and (2) to compare findings with multidetector computed tomography (MDCT) and cone beam CT (CBCT). Four porcine mandibles were examined with (1) 3T-MRI, (2) MDCT and (3) CBCT. Two observers independently reviewed MR, MDCT and CBCT images and assessed image quality of different dental and periodontal structures. To assess quantitatively the accuracy of the different imaging technique, both observers measured burr holes, previously drilled in the mandibles. Dental structures, e.g. teeth roots, pulpa chamber and dentin, were imaged accurately with all imaging sources. Periodontal space and cortical/trabecular bone were better visualized by MRI (p < 0.001). MRI could excellently display the lamina dura, not detectable with MDCT and only inconstant visible with CBCT (p < 0.001). Burr hole measurements were highly precise with all imaging techniques. This experimental study shows the diagnostic feasibility of MRI in visualization of teeth and periodontal anatomy. Detection of periodontal structures was significantly better with MRI than with MDCT or CBCT. Prospective trials have to evaluate further the potential benefit of MRI in a clinical setting. (orig.)

  8. Imaging gait analysis: An fMRI dual task study.

    Science.gov (United States)

    Bürki, Céline N; Bridenbaugh, Stephanie A; Reinhardt, Julia; Stippich, Christoph; Kressig, Reto W; Blatow, Maria

    2017-08-01

    In geriatric clinical diagnostics, gait analysis with cognitive-motor dual tasking is used to predict fall risk and cognitive decline. To date, the neural correlates of cognitive-motor dual tasking processes are not fully understood. To investigate these underlying neural mechanisms, we designed an fMRI paradigm to reproduce the gait analysis. We tested the fMRI paradigm's feasibility in a substudy with fifteen young adults and assessed 31 healthy older adults in the main study. First, gait speed and variability were quantified using the GAITRite © electronic walkway. Then, participants lying in the MRI-scanner were stepping on pedals of an MRI-compatible stepping device used to imitate gait during functional imaging. In each session, participants performed cognitive and motor single tasks as well as cognitive-motor dual tasks. Behavioral results showed that the parameters of both gait analyses, GAITRite © and fMRI, were significantly positively correlated. FMRI results revealed significantly reduced brain activation during dual task compared to single task conditions. Functional ROI analysis showed that activation in the superior parietal lobe (SPL) decreased less from single to dual task condition than activation in primary motor cortex and in supplementary motor areas. Moreover, SPL activation was increased during dual tasks in subjects exhibiting lower stepping speed and lower executive control. We were able to simulate walking during functional imaging with valid results that reproduce those from the GAITRite © gait analysis. On the neural level, SPL seems to play a crucial role in cognitive-motor dual tasking and to be linked to divided attention processes, particularly when motor activity is involved.

  9. Study of some physical aspects previous to design of an exponential experiment

    International Nuclear Information System (INIS)

    Caro, R.; Francisco, J. L. de

    1961-01-01

    This report presents the theoretical study of some physical aspects previous to the design of an exponential facility. The are: Fast and slow flux distribution in the multiplicative medium and in the thermal column, slowing down in the thermal column, geometrical distribution and minimum needed intensity of sources access channels and perturbations produced by possible variations in its position and intensity. (Author) 4 refs

  10. Feasibility study on 3D image reconstruction from 2D orthogonal cine-MRI for MRI-guided radiotherapy.

    Science.gov (United States)

    Paganelli, Chiara; Lee, Danny; Kipritidis, John; Whelan, Brendan; Greer, Peter B; Baroni, Guido; Riboldi, Marco; Keall, Paul

    2018-02-11

    In-room MRI is a promising image guidance strategy in external beam radiotherapy to acquire volumetric information for moving targets. However, limitations in spatio-temporal resolution led several authors to use 2D orthogonal images for guidance. The aim of this work is to present a method to concurrently compensate for non-rigid tumour motion and provide an approach for 3D reconstruction from 2D orthogonal cine-MRI slices for MRI-guided treatments. Free-breathing sagittal/coronal interleaved 2D cine-MRI were acquired in addition to a pre-treatment 3D volume in two patients. We performed deformable image registration (DIR) between cine-MRI slices and corresponding slices in the pre-treatment 3D volume. Based on an extrapolation of the interleaved 2D motion fields, the 3D motion field was estimated and used to warp the pre-treatment volume. Due to the lack of a ground truth for patients, the method was validated on a digital 4D lung phantom. On the phantom, the 3D reconstruction method was able to compensate for tumour motion and compared favourably to the results of previously adopted strategies. The difference in the 3D motion fields between the phantom and the extrapolated motion was 0.4 ± 0.3 mm for tumour and 0.8 ± 1.5 mm for whole anatomy, demonstrating feasibility of performing a 3D volumetric reconstruction directly from 2D orthogonal cine-MRI slices. Application of the method to patient data confirmed the feasibility of utilizing this method in real world scenarios. Preliminary results on phantom and patient cases confirm the feasibility of the proposed approach in an MRI-guided scenario, especially for non-rigid tumour motion compensation. © 2018 The Royal Australian and New Zealand College of Radiologists.

  11. Longitudinal MRI studies of brain morphometry

    DEFF Research Database (Denmark)

    Skimminge, Arnold Jesper Møller

    High resolution MR images acquired at multiple time points of the brain allow quantification of localized changes induced by external factors such as maturation, ageing or disease progression/recovery. High-dimensional warping of such MR images incorporates changes induced by external factors...... into the accompanying deformation field. Deformation fields from high dimensional warping founds tensor based morphometry (TBM), and provides unique opportunities to study human brain morphology and plasticity. In this thesis, specially adapted image processing streams utilizing several image registration techniques...... to characterize differences between brains, demonstrate the versatility and specificity of the employed voxel-wise morphometric methods. More specifically TBM is used to study neurodegenerative changes following severe traumatic brain injuries. Such injuries progress for months, perhaps even years postinjury...

  12. The studies on the salivary scintigraphy and magnetic resonance imaging (MRI) in patients with Sjoegren's syndrome

    International Nuclear Information System (INIS)

    Ogawa, Yoshimi

    1997-01-01

    In order to establish more precise diagnostic criteria for the salivary gland disorder in patients with Sjoegren's syndrome (SS), the scintigraphic (SG) and magnetic resonance imaging (MRI) studies were performed on the salivary glands. The subjects consisted to 180 SS patients, 26 suspected of having SS and 27 normal subjects. Judging from the the grade 1.5 disorder which was set by our new grading of SG, the diagnostic sensitivity of SS was 80.6% and the specificity was 88.9%. This result was better than criteria reported in previous literature. The Speaman rank correlation coefficient of the grading of SG with the Saxon test was 0.56, with the gum test 0.47 and the focus score of the labial gland biopsy 0.40. There was a weak correlation of SG with other serologic tests such as the level of the gamma globulin, IgG and anti-Ro/SS-A autoantibody. The MRI was graded from 0 to 4 according to the change of the signal intensity and the pattern evaluated by T1- and T2-weighted images. There was a correlation of the MRI grading with SG, the focus score and the gum test. This result indicates that MRI is a useful tool to evaluate salivary gland disorders in SS patients. According to our results, a proposal of a revised criteria of salivary gland disorders in SS was presented. (author)

  13. Study of functional-performance deficits in athletes with previous ankle sprains

    Directory of Open Access Journals (Sweden)

    hamid Babaee

    2008-04-01

    Full Text Available Abstract Background: Despite the importance of functional-performance deficits in athletes with history of ankle sprain few, studies have been carried out in this area. The aim of this research was to study relationship between previous ankle sprains and functional-performance deficits in athletes. Materials and methods: The subjects were 40 professional athletes selected through random sampling among volunteer participants in soccer, basketball, volleyball and handball teams of Lorestan province. The subjects were divided into 2 groups: Injured group (athletes with previous ankle sprains and healthy group (athletes without previous ankle sprains. In this descriptive study we used Functional-performance tests (figure 8 hop test and side hop test to determine ankle deficits and limitations. They participated in figure 8 hop test including hopping in 8 shape course with the length of 5 meters and side hop test including 10 side hop repetitions in course with the length of 30 centimeters. Time were recorded via stopwatch. Results: After data gathering and assessing information distributions, Pearson correlation was used to assess relationships, and independent T test to assess differences between variables. Finally the results showed that there is a significant relationship between previous ankle sprains and functional-performance deficits in the athletes. Conclusion: The athletes who had previous ankle sprains indicated functional-performance deficits more than healthy athletes in completion of mentioned functional-performance tests. The functional-performance tests (figure 8 hop test and side hop test are sensitive and suitable to assess and detect functional-performance deficits in athletes. Therefore we can use the figure 8 hop and side hop tests for goals such as prevention, assessment and rehabilitation of ankle sprains without spending too much money and time.

  14. MRI compatibility of robot actuation techniques--a comparative study.

    Science.gov (United States)

    Fischer, Gregory S; Krieger, Axel; Iordachita, Iulian; Csoma, Csaba; Whitcomb, Louis L; Gabor, Fichtinger

    2008-01-01

    This paper reports an experimental evaluation of the following three different MRI-compatible actuators: a Shinsei ultrasonic motor a Nanomotion ultrasonic motor and a pneumatic cylinder actuator. We report the results of a study comparing the effect of these actuators on the signal to noise ratio (SNR) of MRJ images under a variety of experimental conditions. Evaluation was performed with the controller inside and outside the scanner room and with both 1.5T and 3T MRI scanners. Pneumatic cylinders function with no loss of SNR with controller both inside and outside of the scanner room. The Nanomotion motor performs with moderate loss of SNR when moving during imaging. The Shinsei is unsuitable for motion during imaging. All may be used when motion is appropriately interleaved with imaging cycles.

  15. Case of prostate cancer with anterior localization multiparametric MRI study

    International Nuclear Information System (INIS)

    Georgiev, A.

    2016-01-01

    Prostate cancer most often originates from acinar epithelium. Most of the clinically palpable carcinomas are located predominantly in the rear/dorzo-lateraI zones of the gland, but the tumors in the transition zone anatomical may spread to the periphery. The detection of a neoplastic process in the front parts of the gland is rare and poses difficulties in diagnosis. We present a rare case of anterior location of prostate carcinoma with invasion of bladder, blood vessels and seminal vesicles. At present, diagnosis of prostate cancer in most men is demonstrated by elevated serum levels of prostate-specific antigen (PSA), or positive rectal examination or ultrasonography. Multi parametric MR study is a promising method for detecting prostate cancer. When used in conjunction with PSA values and rectal examination, MRI is increasingly accepted as a standard for the diagnosis and characterization of prostate carcinoma. Key words; Prostate Cancer. Anterior Localization. Multi Parametric MRI

  16. Feasibility study to assess clinical applications of 3-T cine MRI coupled with synchronous audio recording during speech in evaluation of velopharyngeal insufficiency in children

    Energy Technology Data Exchange (ETDEWEB)

    Sagar, Pallavi; Nimkin, Katherine [Massachusetts General Hospital, Department of Radiology, Division of Pediatric Radiology, Boston, MA (United States)

    2014-08-16

    In the past decade, there has been increased utilization of magnetic resonance imaging (MRI) in evaluating and understanding velopharyngeal insufficiency (VPI). To our knowledge, none of the prior studies with MRI has simultaneously linked the audio recordings of speech during cine MRI acquisition with the corresponding images and created a video for evaluating VPI. To develop an MRI protocol with static and cine sequences during phonation to evaluate for VPI in children and compare the findings to nasopharyngoscopy and videofluoroscopy. Five children, ages 8-16 years, with known VPI, who had previously undergone nasopharyngoscopy and videofluoroscopy, were included. MRI examination was performed on a 3-T Siemens scanner. Anatomical data was obtained using an isotropic T2-weighted 3-D SPACE sequence with multiplanar reformation capability. Dynamic data was obtained using 2-D FLASH cine sequences of the airway in three imaging planes during phonation. Audio recordings were captured by a MRI compatible optical microphone. All five cases had MRI and nasopharyngoscopy and four had videofluoroscopy performed. VPI was identified by MRI in all five patients. The location and severity of the velopharyngeal gap, closure pattern, velar size and shape and levator veli palatini (LVP) muscle were identified in all patients. MRI was superior in visualizing the integrity of the LVP muscle. MRI was unable to identify hemipalatal weakness in one case. In a case of stress-induced VPI, occurring only during clarinet playing, cine MRI demonstrated discordant findings of a velopharyngeal gap during phonatory tasks but not with instrument playing. Overall, there was satisfactory correlation among MRI, nasopharyngoscopy and videofluoroscopy findings. Cine MRI of the airway during speech is a noninvasive, well-tolerated diagnostic imaging tool that has the potential to serve as a guide prior to and after surgical correction of VPI. MRI provided superior anatomical detail of the levator

  17. Feasibility study to assess clinical applications of 3-T cine MRI coupled with synchronous audio recording during speech in evaluation of velopharyngeal insufficiency in children.

    Science.gov (United States)

    Sagar, Pallavi; Nimkin, Katherine

    2015-02-01

    In the past decade, there has been increased utilization of magnetic resonance imaging (MRI) in evaluating and understanding velopharyngeal insufficiency (VPI). To our knowledge, none of the prior studies with MRI has simultaneously linked the audio recordings of speech during cine MRI acquisition with the corresponding images and created a video for evaluating VPI. To develop an MRI protocol with static and cine sequences during phonation to evaluate for VPI in children and compare the findings to nasopharyngoscopy and videofluoroscopy. Five children, ages 8-16 years, with known VPI, who had previously undergone nasopharyngoscopy and videofluoroscopy, were included. MRI examination was performed on a 3-T Siemens scanner. Anatomical data was obtained using an isotropic T2-weighted 3-D SPACE sequence with multiplanar reformation capability. Dynamic data was obtained using 2-D FLASH cine sequences of the airway in three imaging planes during phonation. Audio recordings were captured by a MRI compatible optical microphone. All five cases had MRI and nasopharyngoscopy and four had videofluoroscopy performed. VPI was identified by MRI in all five patients. The location and severity of the velopharyngeal gap, closure pattern, velar size and shape and levator veli palatini (LVP) muscle were identified in all patients. MRI was superior in visualizing the integrity of the LVP muscle. MRI was unable to identify hemipalatal weakness in one case. In a case of stress-induced VPI, occurring only during clarinet playing, cine MRI demonstrated discordant findings of a velopharyngeal gap during phonatory tasks but not with instrument playing. Overall, there was satisfactory correlation among MRI, nasopharyngoscopy and videofluoroscopy findings. Cine MRI of the airway during speech is a noninvasive, well-tolerated diagnostic imaging tool that has the potential to serve as a guide prior to and after surgical correction of VPI. MRI provided superior anatomical detail of the levator

  18. Feasibility study to assess clinical applications of 3-T cine MRI coupled with synchronous audio recording during speech in evaluation of velopharyngeal insufficiency in children

    International Nuclear Information System (INIS)

    Sagar, Pallavi; Nimkin, Katherine

    2015-01-01

    In the past decade, there has been increased utilization of magnetic resonance imaging (MRI) in evaluating and understanding velopharyngeal insufficiency (VPI). To our knowledge, none of the prior studies with MRI has simultaneously linked the audio recordings of speech during cine MRI acquisition with the corresponding images and created a video for evaluating VPI. To develop an MRI protocol with static and cine sequences during phonation to evaluate for VPI in children and compare the findings to nasopharyngoscopy and videofluoroscopy. Five children, ages 8-16 years, with known VPI, who had previously undergone nasopharyngoscopy and videofluoroscopy, were included. MRI examination was performed on a 3-T Siemens scanner. Anatomical data was obtained using an isotropic T2-weighted 3-D SPACE sequence with multiplanar reformation capability. Dynamic data was obtained using 2-D FLASH cine sequences of the airway in three imaging planes during phonation. Audio recordings were captured by a MRI compatible optical microphone. All five cases had MRI and nasopharyngoscopy and four had videofluoroscopy performed. VPI was identified by MRI in all five patients. The location and severity of the velopharyngeal gap, closure pattern, velar size and shape and levator veli palatini (LVP) muscle were identified in all patients. MRI was superior in visualizing the integrity of the LVP muscle. MRI was unable to identify hemipalatal weakness in one case. In a case of stress-induced VPI, occurring only during clarinet playing, cine MRI demonstrated discordant findings of a velopharyngeal gap during phonatory tasks but not with instrument playing. Overall, there was satisfactory correlation among MRI, nasopharyngoscopy and videofluoroscopy findings. Cine MRI of the airway during speech is a noninvasive, well-tolerated diagnostic imaging tool that has the potential to serve as a guide prior to and after surgical correction of VPI. MRI provided superior anatomical detail of the levator

  19. Sensitivity of MRI in detecting alveolar infiltrates. Experimental studies

    International Nuclear Information System (INIS)

    Biederer, J.; Busse, I.; Grimm, J.; Reuter, M.; Heller, M.; Muhle, C.; Freitag, S.

    2002-01-01

    Purpose: An experimental study using porcine lung explants and a dedicated chest phantom to evaluate the signal intensity of artificial alveolar infiltrates with T 1 - and T 2 -weighted MRI sequences. Material and Methods: 10 porcine lung explants were intubated, transferred into the cavity of a MRI-compatible chest phantom and inflated by continuous evacuation of the artificial pleural space. All lungs were examined with MRI at 1.5 T before and after intra-tracheal instillation of either 100 or 200 ml gelatine-stabilised liquid to simulate alveolar infiltrates. MR-examination comprised gradient echo (2D- and 3D-GRE) and fast spin echo sequences (T 2 -TSE and T 2 -HASTE). The signal intensity of lung parenchyma was evaluated at representative cross sections using a standardised scheme. Control studies were acquired with helical CT. Results: The instilled liquid caused patchy confluent alveolar infiltrates resembling the findings in patients with pneumonia or ARDS. CT revealed typical ground-glass opacities. Before the application of the liquid, only T 2 -HASTE and T 2 -TSE displayed lung parenchyma signals with a signal/noise ratio of 3.62 and 1.39, respectively. After application of the liquid, both T 2 -weighted sequences showed clearly visible infiltrates with an increase in signal intensity of approx. 30% at 100 ml (p 2 -weighted sequences detects artificial alveolar infiltrates with high signal intensity and may be a highly sensitive tool to detect pneumonia in patients. (orig.) [de

  20. Change in brain and lesion volumes after CEE therapies: the WHIMS-MRI studies.

    Science.gov (United States)

    Coker, Laura H; Espeland, Mark A; Hogan, Patricia E; Resnick, Susan M; Bryan, R Nick; Robinson, Jennifer G; Goveas, Joseph S; Davatzikos, Christos; Kuller, Lewis H; Williamson, Jeff D; Bushnell, Cheryl D; Shumaker, Sally A

    2014-02-04

    To determine whether smaller brain volumes in older women who had completed Women's Health Initiative (WHI)-assigned conjugated equine estrogen-based hormone therapy (HT), reported by WHI Memory Study (WHIMS)-MRI, correspond to a continuing increased rate of atrophy an average of 6.1 to 7.7 years later in WHIMS-MRI2. A total of 1,230 WHI participants were contacted: 797 (64.8%) consented, and 729 (59%) were rescanned an average of 4.7 years after the initial MRI scan. Mean annual rates of change in total brain volume, the primary outcome, and rates of change in ischemic lesion volumes, the secondary outcome, were compared between treatment groups using mixed-effect models with adjustment for trial, clinical site, age, intracranial volumes, and time between MRI measures. Total brain volume decreased an average of 3.22 cm(3)/y in the active arm and 3.07 cm(3)/y in the placebo arm (p = 0.53). Total ischemic lesion volumes increased in both arms at a rate of 0.12 cm(3)/y (p = 0.88). Conjugated equine estrogen-based postmenopausal HT, previously assigned at WHI baseline, did not affect rates of decline in brain volumes or increases in brain lesion volumes during the 4.7 years between the initial and follow-up WHIMS-MRI studies. Smaller frontal lobe volumes were observed as persistent group differences among women assigned to active HT compared with placebo. Women with a history of cardiovascular disease treated with active HT, compared with placebo, had higher rates of accumulation in white matter lesion volume and total brain lesion volume. Further study may elucidate mechanisms that explain these findings.

  1. Comparative studies of brain activation with MEG and functional MRI

    International Nuclear Information System (INIS)

    George, J.S.; Aine, C.J.; Sanders, J.A.; Lewine, J.D.; Caprihan, A.

    1993-01-01

    The past two years have witnessed the emergence of MRI as a functional imaging methodology. Initial demonstrations involved the injection of a paramagnetic contrast agent and required ultrafast echo planar imaging capability to adequately resolve the passage of the injected bolus. By measuring the local reduction in image intensity due to magnetic susceptibility, it was possible to calculate blood volume, which changes as a function of neural activation. Later developments have exploited endogenous contrast mechanisms to monitor changes in blood volume or in venous blood oxygen content. Recently, we and others have demonstrated that it is possible to make such measurements in a clinical imager, suggesting that the large installed base of such machines might be utilized for functional imaging. Although it is likely that functional MRI (fMRI) will subsume some of the clinical and basic neuroscience applications now touted for MEG, it is also clear that these techniques offer different largely complementary, capabilities. At the very least, it is useful to compare and cross-validate the activation maps produced by these techniques. Such studies will be valuable as a check on results of neuromagnetic distributed current reconstructions and will allow better characterization of the relationship between neurophysiological activation and associated hemodynamic changes. A more exciting prospect is the development of analyses that combine information from the two modalities to produce a better description of underlying neural activity than is possible with either technique in isolation. In this paper we describe some results from initial comparative studies and outline several techniques that can be used to treat MEG and fMRI data within a unified computational framework

  2. Functional MRI of Handwriting Tasks: A Study of Healthy Young Adults Interacting with a Novel Touch-Sensitive Tablet.

    Science.gov (United States)

    Karimpoor, Mahta; Churchill, Nathan W; Tam, Fred; Fischer, Corinne E; Schweizer, Tom A; Graham, Simon J

    2018-01-01

    Handwriting is a complex human activity that engages a blend of cognitive and visual motor skills. Current understanding of the neural correlates of handwriting has largely come from lesion studies of patients with impaired handwriting. Task-based fMRI studies would be useful to supplement this work. To address concerns over ecological validity, previously we developed a fMRI-compatible, computerized tablet system for writing and drawing including visual feedback of hand position and an augmented reality display. The purpose of the present work is to use the tablet system in proof-of-concept to characterize brain activity associated with clinically relevant handwriting tasks, originally developed to characterize handwriting impairments in Alzheimer's disease patients. As a prelude to undertaking fMRI studies of patients, imaging was performed of twelve young healthy subjects who copied sentences, phone numbers, and grocery lists using the fMRI-compatible tablet. Activation maps for all handwriting tasks consisted of a distributed network of regions in reasonable agreement with previous studies of handwriting performance. In addition, differences in brain activity were observed between the test subcomponents consistent with different demands of neural processing for successful task performance, as identified by investigating three quantitative behavioral metrics (writing speed, stylus contact force and stylus in air time). This study provides baseline behavioral and brain activity results for fMRI studies that adopt this handwriting test to characterize patients with brain impairments.

  3. Functional MRI of Handwriting Tasks: A Study of Healthy Young Adults Interacting with a Novel Touch-Sensitive Tablet

    Directory of Open Access Journals (Sweden)

    Mahta Karimpoor

    2018-02-01

    Full Text Available Handwriting is a complex human activity that engages a blend of cognitive and visual motor skills. Current understanding of the neural correlates of handwriting has largely come from lesion studies of patients with impaired handwriting. Task-based fMRI studies would be useful to supplement this work. To address concerns over ecological validity, previously we developed a fMRI-compatible, computerized tablet system for writing and drawing including visual feedback of hand position and an augmented reality display. The purpose of the present work is to use the tablet system in proof-of-concept to characterize brain activity associated with clinically relevant handwriting tasks, originally developed to characterize handwriting impairments in Alzheimer’s disease patients. As a prelude to undertaking fMRI studies of patients, imaging was performed of twelve young healthy subjects who copied sentences, phone numbers, and grocery lists using the fMRI-compatible tablet. Activation maps for all handwriting tasks consisted of a distributed network of regions in reasonable agreement with previous studies of handwriting performance. In addition, differences in brain activity were observed between the test subcomponents consistent with different demands of neural processing for successful task performance, as identified by investigating three quantitative behavioral metrics (writing speed, stylus contact force and stylus in air time. This study provides baseline behavioral and brain activity results for fMRI studies that adopt this handwriting test to characterize patients with brain impairments.

  4. Functional MRI of Handwriting Tasks: A Study of Healthy Young Adults Interacting with a Novel Touch-Sensitive Tablet

    Science.gov (United States)

    Karimpoor, Mahta; Churchill, Nathan W.; Tam, Fred; Fischer, Corinne E.; Schweizer, Tom A.; Graham, Simon J.

    2018-01-01

    Handwriting is a complex human activity that engages a blend of cognitive and visual motor skills. Current understanding of the neural correlates of handwriting has largely come from lesion studies of patients with impaired handwriting. Task-based fMRI studies would be useful to supplement this work. To address concerns over ecological validity, previously we developed a fMRI-compatible, computerized tablet system for writing and drawing including visual feedback of hand position and an augmented reality display. The purpose of the present work is to use the tablet system in proof-of-concept to characterize brain activity associated with clinically relevant handwriting tasks, originally developed to characterize handwriting impairments in Alzheimer’s disease patients. As a prelude to undertaking fMRI studies of patients, imaging was performed of twelve young healthy subjects who copied sentences, phone numbers, and grocery lists using the fMRI-compatible tablet. Activation maps for all handwriting tasks consisted of a distributed network of regions in reasonable agreement with previous studies of handwriting performance. In addition, differences in brain activity were observed between the test subcomponents consistent with different demands of neural processing for successful task performance, as identified by investigating three quantitative behavioral metrics (writing speed, stylus contact force and stylus in air time). This study provides baseline behavioral and brain activity results for fMRI studies that adopt this handwriting test to characterize patients with brain impairments. PMID:29487511

  5. MRI and unilateral NMR study of reindeer skin tanning processes.

    Science.gov (United States)

    Zhu, Lizheng; Del Federico, Eleonora; Ilott, Andrew J; Klokkernes, Torunn; Kehlet, Cindie; Jerschow, Alexej

    2015-04-07

    The study of arctic or subarctic indigenous skin clothing material, known for its design and ability to keep the body warm, provides information about the tanning materials and techniques. The study also provides clues about the culture that created it, since tanning processes are often specific to certain indigenous groups. Untreated skin samples and samples treated with willow (Salix sp) bark extract and cod liver oil are compared in this study using both MRI and unilateral NMR techniques. The two types of samples show different proton spatial distributions and different relaxation times, which may also provide information about the tanning technique and aging behavior.

  6. Cognitive dissonance induction in everyday life: An fMRI study.

    Science.gov (United States)

    de Vries, Jan; Byrne, Mark; Kehoe, Elizabeth

    2015-01-01

    This functional magnetic resonance imaging (fMRI) study explored the neural substrates of cognitive dissonance during dissonance "induction." A novel task was developed based on the results of a separate item selection study (n = 125). Items were designed to generate dissonance by prompting participants to reflect on everyday personal experiences that were inconsistent with values they had expressed support for. One experimental condition (dissonance) and three control conditions (justification, consonance, and non-self-related inconsistency) were used for comparison. Items of all four types were presented to each participant (n = 14) in a randomized design. The fMRI analysis used a whole-brain approach focusing on the moments dissonance was induced. Results showed that in comparison with the control conditions the dissonance experience led to higher levels of activation in several brain regions. Specifically dissonance was associated with increased neural activation in key brain regions including the anterior cingulate cortex (ACC), anterior insula, inferior frontal gyrus, and precuneus. This supports current perspectives that emphasize the role of anterior cingulate and insula in dissonance processing. Less extensive activation in the prefrontal cortex than in some previous studies is consistent with this study's emphasis on dissonance induction, rather than reduction. This article also contains a short review and comparison with other fMRI studies of cognitive dissonance.

  7. Serial MRI studies using gadolinium DTPA in active multiple sclerosis

    International Nuclear Information System (INIS)

    Miller, D.H.; Johnson, G.; Barnes, D.; Rudge, P.; McDonald, W.I.

    1988-01-01

    It has been suggested that blood brain barrier (BBB) impairment is a necessary early event in the pathogenesis of the multiple sclerosis (MS) lesions. To evaluate such an hypothesis in vivo would require: (1) serial imaging studies using a modality with high sensitivity for detecting plaques; (2) a contrast enhancing agent which demonstrates BBB impairment. A serial magnetic resonance imaging (MRI) study was undertaken of a group of MS patients using the contrast agent gadolinium-DTPA. As it has been suggested that T 1 and T 2 relaxation times are longer in acute than chronic MS lesions, these were also measured. 3 refs.; 1 figure

  8. Data from studies of previous radioactive waste disposal in Massachusetts Bay

    International Nuclear Information System (INIS)

    Curtis, W.R.; Mardis, H.M.

    1984-12-01

    This report presents the results of studies conducted in Massachusetts Bay during 1981 and 1982. Included are data from: (1) a side scan sonar survey of disposal areas in the Bay that was carried out by the National Oceanic and Atmospheric Administration (NOAA) for EPA; (2) Collections of sediment and biota by NOAA for radiochemical analysis by EPA; (3) collections of marketplace seafood samples by the Food and Drug Administration (FDA) for radioanalysis by both FDA and EPA; and (4) a radiological monitoring survey of LLW disposal areas by EPA to determine whether there should be any concern for public health resulting from previous LLW disposals in the Bay

  9. The power of using functional fMRI on small rodents to study brain pharmacology and disease

    OpenAIRE

    Jonckers, Elisabeth; Shah, Disha; Hamaide, Julie; Verhoye, Marleen; Van der Linden, Annemie

    2015-01-01

    Abstract: Functional magnetic resonance imaging (fMRI) is an excellent tool to study the effect of pharmacological modulations on brain function in a non-invasive and longitudinal manner. We introduce several blood oxygenation level dependent (BOLD) fMRI techniques, including resting state (rsfMRI), stimulus-evoked (st-fMRI), and pharmacological MRI (phMRI). Respectively, these techniques permit the assessment of functional connectivity during rest as well as brain activation triggered by sen...

  10. Motor association cortex activity in Parkinson's disease. A functional MRI study

    International Nuclear Information System (INIS)

    Tada, Yukiko

    1998-01-01

    The purpose of this study was to examine the activation of motor association cortex using functional magnetic resonance imaging (fMRI) in patients with Parkinson's disease (PD) and control subjects during performed hand movements. There were 26 patients with PD (12 patients with Hoehn and Yahr stage I-II, 14 patients with stage III) and 8 control subjects. Functional imaging was performed using a 1.5 tesla MRI system equipped with a single-shot, echo-planar pulse sequence. The significant signal changes were observed within the primary sensorimotor area, the supplementary motor area (SMA), and the parietal association area in both PD and control subjects. In PD subjects, the SMA was less activated than in control subjects; there were significant differences in the number of pixels activated in SMA between control and Yahr III group (p<0.01), and between Yahr I-II and Yahr III group (p<0.01). Our results demonstrated that movement related cerebral activity in the SMA is reduced in PD subjects, consistent with previously published data using other methods. It is well known from anatomical studies that one of the major cortical outputs of the basal ganglia is the SMA. This may explain the hypoactivation of the SMA in PD. Studies using fMRI provide a promising method not only for localizing cortical activation related to voluntary movements but also for investigating pathophysiology of movement disorders. (author)

  11. MRI findings and correlative study of MRI and visual evoked potentials in optic neuritis

    International Nuclear Information System (INIS)

    Yan Fei; Li Jing; Wang Zhenchang; Liu Shoubin; Zhang Xiaojun

    2008-01-01

    Objective: To investigate the effective MRI sequences and describe the correlation between MRI and visual evoked potential (VEP) in diagnosing optic neuritis. Methods: One hundred and fifty-four eyes with visual impairment of 98 patients with diagnoses of optic neuritis, papillitis, multiple sclerosis and Devic's disease underwent MRI and VEP examination. The MRI findings were analyzed and correlated with VEP results and clinical presentation by using X 2 test, wilco xon test and Kappa test. Results Out of the 154 sick eyes, 56 eyes presented thickened optic nerves, 76 eyes had normal diameter of the optic nerve, and 22 eyes had thin optic nerves. A total of 132 optic nerves showed abnormally high signal in STIR sequences, including involvement of intraocular segment in 7, intraorbital segment in 1.35, intracanalicular segment in 109, intracranial segment in 97, optic chiasm in 56, and optic tract in 23. A total of 54 patients underwent postcontrast MRI. Seventy-four optic nerves of 87 eyes showed enhancement. Among the 196 eyes of 98 patients, 132 eyes presented visual impairment and simultaneous abnormal MR signal of the optic nerve, and 26 eyes had both normal vision and normal MR signal of optic nerve. The consistency of MRI findings and vision status was 80. 61% (Kappa 0.453,P 1 -weighted MR sequence combined with fat- suppression are helpful in diagnosis of optic neuritis. VEP is helpful in diagnosing optic neuritis and in finding subclinical visual problem. The MRI combined with VEP could improve the diagnostic accuracy of optic neuritis. (authors)

  12. Juxtafacet cysts of the lumbar spine: a positional MRI study

    International Nuclear Information System (INIS)

    Niggemann, Pascal; Kuchta, Johannes; Hoeffer, Janine; Beyer, Hans-Konrad; Grosskurth, Dieter; Delank, Karl-Stefan

    2012-01-01

    Juxtafacet cysts (JFC) are related to facet joint degeneration. Supine MRI is routinely used to evaluate JFC. However, some JFC are missed and found only intraoperatively. The present study addresses positional MRI features and factors leading to variation in the size of JFC. Fifty patients in whom positional MRI had been performed were investigated retrospectively and 67 distinct intraspinal or intraneuroforaminal were JFC found. Signal intensity, size of the JFC, the presence and variance of a vertebral slip and the angular movement of affected segments were assessed in supine, neutral sitting, flexion (sitting) and extension (standing). The overall movement of the spine and the lordosis angle in different positions were measured. JFC varied in size in segments with unstable slip and increased angular movement (variation of the angle in the affected segment in function: 13.3 degrees compared to 8.7 degrees). JFC with bright signals tended to vary in size compared to JFC with intermediate or low signal intensity (all: p < 0.001). Joint effusion and displacement of effusion lead to formation and variations in the size of JFC. JFC were most prominent in extension: 6.7 mm, less prominent in supine: 5.5 mm and in neutral sitting position: 4.6 mm (all p < 0.05). The detection rate for JFC was 97% for extension, 89% for supine and 78% for neutral sitting. The detection rate of JFC improves with increasing lordosis of the spine and under weight-bearing conditions, particularly when standing. Unstable slipping or increased angular movement affects the size of JFC. (orig.)

  13. Juxtafacet cysts of the lumbar spine: a positional MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Niggemann, Pascal [University Hospital Bonn, Department of Radiology, Bonn (Germany); Kuchta, Johannes [Interdisziplinaeres Wirbelsaeulenzentrum, Bonn (Germany); Hoeffer, Janine; Beyer, Hans-Konrad [Upright MRT, Cologne (Germany); Grosskurth, Dieter; Delank, Karl-Stefan [Upright MRT, Cologne (Germany); University of Cologne, Department of Orthopaedic and Trauma Surgery, Cologne (Germany)

    2012-03-15

    Juxtafacet cysts (JFC) are related to facet joint degeneration. Supine MRI is routinely used to evaluate JFC. However, some JFC are missed and found only intraoperatively. The present study addresses positional MRI features and factors leading to variation in the size of JFC. Fifty patients in whom positional MRI had been performed were investigated retrospectively and 67 distinct intraspinal or intraneuroforaminal were JFC found. Signal intensity, size of the JFC, the presence and variance of a vertebral slip and the angular movement of affected segments were assessed in supine, neutral sitting, flexion (sitting) and extension (standing). The overall movement of the spine and the lordosis angle in different positions were measured. JFC varied in size in segments with unstable slip and increased angular movement (variation of the angle in the affected segment in function: 13.3 degrees compared to 8.7 degrees). JFC with bright signals tended to vary in size compared to JFC with intermediate or low signal intensity (all: p < 0.001). Joint effusion and displacement of effusion lead to formation and variations in the size of JFC. JFC were most prominent in extension: 6.7 mm, less prominent in supine: 5.5 mm and in neutral sitting position: 4.6 mm (all p < 0.05). The detection rate for JFC was 97% for extension, 89% for supine and 78% for neutral sitting. The detection rate of JFC improves with increasing lordosis of the spine and under weight-bearing conditions, particularly when standing. Unstable slipping or increased angular movement affects the size of JFC. (orig.)

  14. Medial tibial pain: a dynamic contrast-enhanced MRI study.

    Science.gov (United States)

    Mattila, K T; Komu, M E; Dahlström, S; Koskinen, S K; Heikkilä, J

    1999-09-01

    The purpose of this study was to compare the sensitivity of different magnetic resonance imaging (MRI) sequences to depict periosteal edema in patients with medial tibial pain. Additionally, we evaluated the ability of dynamic contrast-enhanced imaging (DCES) to depict possible temporal alterations in muscular perfusion within compartments of the leg. Fifteen patients with medial tibial pain were examined with MRI. T1-, T2-weighted, proton density axial images and dynamic and static phase post-contrast images were compared in ability to depict periosteal edema. STIR was used in seven cases to depict bone marrow edema. Images were analyzed to detect signs of compartment edema. Region-of-interest measurements in compartments were performed during DCES and compared with controls. In detecting periosteal edema, post-contrast T1-weighted images were better than spin echo T2-weighted and proton density images or STIR images, but STIR depicted the bone marrow edema best. DCES best demonstrated the gradually enhancing periostitis. Four subjects with severe periosteal edema had visually detectable pathologic enhancement during DCES in the deep posterior compartment of the leg. Percentage enhancement in the deep posterior compartment of the leg was greater in patients than in controls. The fast enhancement phase in the deep posterior compartment began slightly slower in patients than in controls, but it continued longer. We believe that periosteal edema in bone stress reaction can cause impairment of venous flow in the deep posterior compartment. MRI can depict both these conditions. In patients with medial tibial pain, MR imaging protocol should include axial STIR images (to depict bone pathology) with T1-weighted axial pre and post-contrast images, and dynamic contrast enhanced imaging to show periosteal edema and abnormal contrast enhancement within a compartment.

  15. Ex-vivo diffusion MRI reveals microstructural alterations in stress-sensitive brain regions: A chronic mild stress recovery study

    DEFF Research Database (Denmark)

    Khan, Ahmad Raza; Hansen, Brian; Wiborg, Ove

    Depression is a leading cause of disability worldwide and causes significant microstructural alterations in stress-sensitive brain regions. However, the potential recovery of these microstructural alterations has not previously been investigated, which we, therefore, set out to do using diffusion...... MRI (d-MRI) in the chronic mild stress (CMS) rat model of depression. This study reveals significant microstructural alterations after 8 weeks of recovery, in the opposite direction to change induced by stress in the acute phase of the experiment. Such findings may be useful in the prognosis...... of depression or for monitoring treatment response....

  16. A longitudinal study of plasma insulin and glucagon in women with previous gestational diabetes

    DEFF Research Database (Denmark)

    Damm, P; Kühl, C; Hornnes, P

    1995-01-01

    OBJECTIVE: To investigate whether plasma insulin or glucagon predicts later development of diabetes in women with gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: The subjects studied were 91 women with diet-treated GDM and 33 healthy women. Plasma insulin and glucagon during a 50...... at follow-up (2 had insulin-dependent diabetes mellitus, 13 had non-insulin-dependent diabetes mellitus, and 12 had impaired glucose tolerance). Compared with the control subjects, women with previous GDM had relatively impaired insulin secretion (decreased insulinogenic index and delayed peak insulin...... for subsequent development of overt diabetes (logistic regression analysis). CONCLUSIONS: Women who develop GDM have a relative insulin secretion deficiency, the severity of which is predictive for later development of diabetes. Furthermore, our data indicate that their relatively reduced beta-cell function may...

  17. Case-control study for colorectal cancer genetic susceptibility in EPICOLON: previously identified variants and mucins

    Directory of Open Access Journals (Sweden)

    Moreno Victor

    2011-08-01

    Full Text Available Abstract Background Colorectal cancer (CRC is the second leading cause of cancer death in developed countries. Familial aggregation in CRC is also important outside syndromic forms and, in this case, a polygenic model with several common low-penetrance alleles contributing to CRC genetic predisposition could be hypothesized. Mucins and GALNTs (N-acetylgalactosaminyltransferase are interesting candidates for CRC genetic susceptibility and have not been previously evaluated. We present results for ten genetic variants linked to CRC risk in previous studies (previously identified category and 18 selected variants from the mucin gene family in a case-control association study from the Spanish EPICOLON consortium. Methods CRC cases and matched controls were from EPICOLON, a prospective, multicenter, nationwide Spanish initiative, comprised of two independent stages. Stage 1 corresponded to 515 CRC cases and 515 controls, whereas stage 2 consisted of 901 CRC cases and 909 controls. Also, an independent cohort of 549 CRC cases and 599 controls outside EPICOLON was available for additional replication. Genotyping was performed for ten previously identified SNPs in ADH1C, APC, CCDN1, IL6, IL8, IRS1, MTHFR, PPARG, VDR and ARL11, and 18 selected variants in the mucin gene family. Results None of the 28 SNPs analyzed in our study was found to be associated with CRC risk. Although four SNPs were significant with a P-value ADH1C (OR = 1.63, 95% CI = 1.06-2.50, P-value = 0.02, recessive, rs1800795 in IL6 (OR = 1.62, 95% CI = 1.10-2.37, P-value = 0.01, recessive, rs3803185 in ARL11 (OR = 1.58, 95% CI = 1.17-2.15, P-value = 0.007, codominant, and rs2102302 in GALNTL2 (OR = 1.20, 95% CI = 1.00-1.44, P-value = 0.04, log-additive 0, 1, 2 alleles], only rs3803185 achieved statistical significance in EPICOLON stage 2 (OR = 1.34, 95% CI = 1.06-1.69, P-value = 0.01, recessive. In the joint analysis for both stages, results were only significant for rs3803185 (OR = 1

  18. Case-control study for colorectal cancer genetic susceptibility in EPICOLON: previously identified variants and mucins

    International Nuclear Information System (INIS)

    Abulí, Anna; Morillas, Juan D; Rigau, Joaquim; Latorre, Mercedes; Fernández-Bañares, Fernando; Peña, Elena; Riestra, Sabino; Payá, Artemio; Jover, Rodrigo; Xicola, Rosa M; Llor, Xavier; Fernández-Rozadilla, Ceres; Carvajal-Carmona, Luis; Villanueva, Cristina M; Moreno, Victor; Piqué, Josep M; Carracedo, Angel; Castells, Antoni; Andreu, Montserrat; Ruiz-Ponte, Clara; Castellví-Bel, Sergi; Alonso-Espinaco, Virginia; Muñoz, Jenifer; Gonzalo, Victoria; Bessa, Xavier; González, Dolors; Clofent, Joan; Cubiella, Joaquin

    2011-01-01

    Colorectal cancer (CRC) is the second leading cause of cancer death in developed countries. Familial aggregation in CRC is also important outside syndromic forms and, in this case, a polygenic model with several common low-penetrance alleles contributing to CRC genetic predisposition could be hypothesized. Mucins and GALNTs (N-acetylgalactosaminyltransferase) are interesting candidates for CRC genetic susceptibility and have not been previously evaluated. We present results for ten genetic variants linked to CRC risk in previous studies (previously identified category) and 18 selected variants from the mucin gene family in a case-control association study from the Spanish EPICOLON consortium. CRC cases and matched controls were from EPICOLON, a prospective, multicenter, nationwide Spanish initiative, comprised of two independent stages. Stage 1 corresponded to 515 CRC cases and 515 controls, whereas stage 2 consisted of 901 CRC cases and 909 controls. Also, an independent cohort of 549 CRC cases and 599 controls outside EPICOLON was available for additional replication. Genotyping was performed for ten previously identified SNPs in ADH1C, APC, CCDN1, IL6, IL8, IRS1, MTHFR, PPARG, VDR and ARL11, and 18 selected variants in the mucin gene family. None of the 28 SNPs analyzed in our study was found to be associated with CRC risk. Although four SNPs were significant with a P-value < 0.05 in EPICOLON stage 1 [rs698 in ADH1C (OR = 1.63, 95% CI = 1.06-2.50, P-value = 0.02, recessive), rs1800795 in IL6 (OR = 1.62, 95% CI = 1.10-2.37, P-value = 0.01, recessive), rs3803185 in ARL11 (OR = 1.58, 95% CI = 1.17-2.15, P-value = 0.007, codominant), and rs2102302 in GALNTL2 (OR = 1.20, 95% CI = 1.00-1.44, P-value = 0.04, log-additive 0, 1, 2 alleles], only rs3803185 achieved statistical significance in EPICOLON stage 2 (OR = 1.34, 95% CI = 1.06-1.69, P-value = 0.01, recessive). In the joint analysis for both stages, results were only significant for rs3803185 (OR = 1.12, 95% CI = 1

  19. Volumetric MRI study of the intrauterine growth restriction fetal brain

    International Nuclear Information System (INIS)

    Polat, A.; Barlow, S.; Ber, R.; Achiron, R.; Katorza, E.

    2017-01-01

    Intrauterine growth restriction (IUGR) is a pathologic fetal condition known to affect the fetal brain regionally and associated with future neurodevelopmental abnormalities. This study employed MRI to assess in utero regional brain volume changes in IUGR fetuses compared to controls. Retrospectively, using MRI images of fetuses at 30-34 weeks gestational age, a total of 8 brain regions - supratentorial brain and cavity, cerebral hemispheres, temporal lobes and cerebellum - were measured for volume in 13 fetuses with IUGR due to placental insufficiency and in 21 controls. Volumes and their ratios were assessed for difference using regression models. Reliability was assessed by intraclass correlation coefficients (ICC) between two observers. In both groups, all structures increase in absolute volume during that gestation period, and the rate of cerebellar growth is higher compared to that of supratentorial structures. All structures' absolute volumes were significantly smaller for the IUGR group. Cerebellar to supratentorial ratios were found to be significantly smaller (P < 0.05) for IUGR compared to controls. No other significant ratio differences were found. ICC showed excellent agreement. The cerebellar to supratentorial volume ratio is affected in IUGR fetuses. Additional research is needed to assess this as a radiologic marker in relation to long-term outcome. (orig.)

  20. Volumetric MRI study of the intrauterine growth restriction fetal brain

    Energy Technology Data Exchange (ETDEWEB)

    Polat, A.; Barlow, S.; Ber, R.; Achiron, R.; Katorza, E. [Tel Aviv University, Sackler School of Medicine, Department of Obstetrics and Gynecology, Chaim Sheba Medical Center, Tel Hashomer (Israel)

    2017-05-15

    Intrauterine growth restriction (IUGR) is a pathologic fetal condition known to affect the fetal brain regionally and associated with future neurodevelopmental abnormalities. This study employed MRI to assess in utero regional brain volume changes in IUGR fetuses compared to controls. Retrospectively, using MRI images of fetuses at 30-34 weeks gestational age, a total of 8 brain regions - supratentorial brain and cavity, cerebral hemispheres, temporal lobes and cerebellum - were measured for volume in 13 fetuses with IUGR due to placental insufficiency and in 21 controls. Volumes and their ratios were assessed for difference using regression models. Reliability was assessed by intraclass correlation coefficients (ICC) between two observers. In both groups, all structures increase in absolute volume during that gestation period, and the rate of cerebellar growth is higher compared to that of supratentorial structures. All structures' absolute volumes were significantly smaller for the IUGR group. Cerebellar to supratentorial ratios were found to be significantly smaller (P < 0.05) for IUGR compared to controls. No other significant ratio differences were found. ICC showed excellent agreement. The cerebellar to supratentorial volume ratio is affected in IUGR fetuses. Additional research is needed to assess this as a radiologic marker in relation to long-term outcome. (orig.)

  1. MRI study of pituitary in girls with central precocious puberty

    International Nuclear Information System (INIS)

    Ye Zhiqiu; Guo Qinglu; Feng Changzheng; Wei Beiyang; Liu Yongxi; Zhang Yan

    2008-01-01

    Objective: To study the shape, size and signal intensity of pituitary gland in girls aged 3-10 year old with central precocious puberty. Methods: MRI data of pituitary glands in 40 girls aged 3-10 years old with central precocious puberty were selected. The shape, height and the appearances of pituitary glands were measured and observed on sagittal T 1 WI. Results: Quantitative data about size, shape and single intensity changes of pituitary glands in central precocious puberty were obtained in two groups, including girls aged from 3-5 and 5-10. The convex pituitary gland were 85.0% in former group. The height of pituitary gland were 6.1±0.2mm (former group) and 6.4± 0.4mm (latter one) respectively. The width of pituitary stalk was 1.93±0.50mm. The posterior pituitary gland demonstrated high signal intensity in all cases. Conclusion: Obvious changes of the size and shape of pituitary glands were found in central precocious puberty of girls aged from 3-10. The pituitary glands manifested physiologic hypertrophy with more convex in central precocious puberty girls than in normal ones. The changes on MRI could reflect the function of hypothalamus-pituitary-gonadal axis. It is of important value and significance in the diagnosis of central precocious puberty. (authors)

  2. A voxel-based MRI morphometric study of Alzheimer's disease

    International Nuclear Information System (INIS)

    Hao Jing; Li Kuncheng; Yang Yanhui; Wang Wei; Li Ke; Yan Bin; Shan Baoci

    2005-01-01

    Objective: To assess the diagnostic value of voxel-based Morphometry (VBM) in studying Alzheimer's disease (AD). Methods: Graymatter density were comprehensive assessed by means of VBM on T 1 -weighted MRI volume sets in 19 patients with AD and 15 healthy subjects of similar age and gender ratio, 15 healthy adults. The data were collected on Siemens 1.5 T Sonata MRI systems and analyzed by SPM 99 to generate gray matter density map. Results: Relative to healthy controls, significant clusters of reduced gray matter density were found to affect medial temporal lobe ( hippocampus) (P<0.001). For hippocampus, reduced gray matter density were 1529 in the right and 1281 in the left with right-sided predominance. Moreover, atrophy of right caudate head and left medial thalamus were showed. We demonstrate global asymmetrical cortical atrophy with sparing of the sensorimotor cortex, occipital lobe and cerebellum. Conclusion: The results from VBM are in perfect agreement with those of earlier neuroimaging, which confirmed its value in demonstrating neuroanatomy of AD. VBM, the simple and automatic approach providing a full-brain assessment of AD morphology, has a good clinical perspective. (authors)

  3. Intrusive Memories of Distressing Information: An fMRI Study.

    Directory of Open Access Journals (Sweden)

    Eva Battaglini

    Full Text Available Although intrusive memories are characteristic of many psychological disorders, the neurobiological underpinning of these involuntary recollections are largely unknown. In this study we used functional magentic resonance imaging (fMRI to identify the neural networks associated with encoding of negative stimuli that are subsequently experienced as intrusive memories. Healthy partipants (N = 42 viewed negative and neutral images during a visual/verbal processing task in an fMRI context. Two days later they were assessed on the Impact of Event Scale for occurrence of intrusive memories of the encoded images. A sub-group of participants who reported significant intrusions (n = 13 demonstrated stronger activation in the amygdala, bilateral ACC and parahippocampal gyrus during verbal encoding relative to a group who reported no intrusions (n = 13. Within-group analyses also revealed that the high intrusion group showed greater activity in the dorsomedial (dmPFC and dorsolateral prefrontal cortex (dlPFC, inferior frontal gyrus and occipital regions during negative verbal processing compared to neutral verbal processing. These results do not accord with models of intrusions that emphasise visual processing of information at encoding but are consistent with models that highlight the role of inhibitory and suppression processes in the formation of subsequent intrusive memories.

  4. A study about the interest and previous contact of high school students with Astronomy

    Science.gov (United States)

    Carvalho, C. L.; Zanitti, M. H. R.; Felicidade, B. L.; Gomes, A. D. T.; Dias, E. W.; Coelho, F. O.

    2016-04-01

    The currently problems in Astronomy teaching in Brazilian Basic Education contrast with the space, and the popularity that astronomical themes have in various media in the country. In this work, we present the results of a study about the interest, and previous contact of high school students from a public school in the city of "São João del-Rei"/MG with topics related to Astronomy. The study and the pedagogical intervention were carried out by students of the PIBID/CAPES/UFSJ. The intervention was performed through an oral exposition with the students' participation, followed by the use of the Stellarium program. The results suggest the majority of students surveyed are interested in Astronomy, and have had some contact with the area. However, some inconsistencies in their responses were identified and examined. The implications for research and for Astronomy Education are discussed. We also make some considerations about relationship between the lack of specific knowledge and the misinformation as one possible reason for the little interest of students in various areas of Science.

  5. Fire Risk Scoping Study: Investigation of nuclear power plant fire risk, including previously unaddressed issues

    International Nuclear Information System (INIS)

    Lambright, J.A.; Nowlen, S.P.; Nicolette, V.F.; Bohn, M.P.

    1989-01-01

    An investigation of nuclear power plant fire risk issues raised as a result of the USNRC sponsored Fire Protection Research Program at Sandia National Laboratories has been performed. The specific objectives of this study were (1) to review and requantify fire risk scenarios from four fire probabilistic risk assessments (PRAs) in light of updated data bases made available as a result of USNRC sponsored Fire Protection Research Program and updated computer fire modeling capabilities, (2) to identify potentially significant fire risk issues that have not been previously addressed in a fire risk context and to quantify the potential impact of those identified fire risk issues where possible, and (3) to review current fire regulations and plant implementation practices for relevance to the identified unaddressed fire risk issues. In performance of the fire risk scenario requantifications several important insights were gained. It was found that utilization of a more extensive operational experience base resulted in both fire occurrence frequencies and fire duration times (i.e., time required for fire suppression) increasing significantly over those assumed in the original works. Additionally, some thermal damage threshold limits assumed in the original works were identified as being nonconservative based on more recent experimental data. Finally, application of the COMPBRN III fire growth model resulted in calculation of considerably longer fire damage times than those calculated in the original works using COMPBRN I. 14 refs., 2 figs., 16 tabs

  6. Specificity of Esthetic Experience for Artworks: An fMRI Study

    Science.gov (United States)

    Di Dio, Cinzia; Canessa, Nicola; Cappa, Stefano F.; Rizzolatti, Giacomo

    2011-01-01

    In a previous functional magnetic resonance imaging (fMRI) study, where we investigated the neural correlates of esthetic experience, we found that observing canonical sculptures, relative to sculptures whose proportions had been modified, produced the activation of a network that included the lateral occipital gyrus, precuneus, prefrontal areas, and, most interestingly, the right anterior insula. We interpreted this latter activation as the neural signature underpinning hedonic response during esthetic experience. With the aim of exploring whether this specific hedonic response is also present during the observation of non-art biological stimuli, in the present fMRI study we compared the activations associated with viewing masterpieces of classical sculpture with those produced by the observation of pictures of young athletes. The two stimulus-categories were matched on various factors, including body postures, proportion, and expressed dynamism. The stimuli were presented in two conditions: observation and esthetic judgment. The two stimulus-categories produced a rather similar global activation pattern. Direct comparisons between sculpture and real-body images revealed, however, relevant differences, among which the activation of right antero-dorsal insula during sculptures viewing only. Along with our previous data, this finding suggests that the hedonic state associated with activation of right dorsal anterior insula underpins esthetic experience for artworks. PMID:22121344

  7. Functional MRI studies of human vision on a clinical imager

    International Nuclear Information System (INIS)

    George, J.S.; Lewine, J.D.; Aine, C.J.; van Hulsteyn, D.; Wood, C.C.; Sanders, J.; Maclin, E.; Belliveau, J.W.; Caprihan, A.

    1992-01-01

    During the past decade, Magnetic Resonance Imaging (MRI) has become the method of choice for imaging the anatomy of the human brain. Recently, Belliveau and colleagues have reported the use of echo planar magnetic resonance imaging (EPI) to image patterns of neural activity. Here, we report functional MR imaging in response to visual stimulation without the use of contrast agents, and without the extensive hardware modifications required for EPI. Regions of activity were observed near the expected locations of V1, V2 and possibly V3 and another active region was observed near the parietal-occipital sulcus on the superior surface of the cerebrum. These locations are consistent with sources observed in neuromagnetic studies of the human visual response

  8. Studying neonatal bilirubin encephalopathy with conventional MRI, MRS, and DWI

    International Nuclear Information System (INIS)

    Wang, Xiaoyi; Wu, Wulin; Chineah, Ashley; Liu, Fan; Liao, Weihua; Hou, Bob L.; Zhang, Ping

    2008-01-01

    The purpose of this study was to evaluate the diagnostic value of conventional magnetic resonance imaging (MRI), proton magnetic resonance spectroscopy ( 1 H-MRS), and diffusion-weighted imaging (DWI) for neonatal bilirubin encephalopathy. We collected conventional MRI in 24 neonates with neonatal bilirubin encephalopathy. We performed 1 H-MRS and DWI sequences to nine of the 24 patients and seven age-matched healthy control subjects. Multiple-voxel 1 H-MRS data were acquired using PRESS pulse sequence with TE=135 ms and TR=1500 ms. The spectroscopic regions of interest were the bilateral basal ganglia and thalamus with a 1.0 mL spatial resolution. The data from DWI were collected by using a single shot-spin echo-echo planar imaging sequence with TR/TE: 2900/98, and imaging regions were also focused on the bilateral basal ganglia and thalamus. Nineteen of the 24 patients had abnormal T 1 -weighted image hyperintensity in the globus pallidus, but these lesions appeared as normal T 2 -weighted image intensity in the same region. Ten of the 24 patients had T 1 -weighted image high signal intensity in the subthalamic nucleus and appeared as normal intensity in the region for the T 2 -weighted images. The peak area ratios of NAA/Cho and NAA/Cr were significantly decreased (t-test, P 1 H-MRS are important complementary tools in the diagnosis of neonatal bilirubin encephalopathy. The study provides important information for applying these MR modalities to evaluate neonates with bilirubin encephalopathy. (orig.)

  9. Sheep head frame validation for CT and MRI studies

    Directory of Open Access Journals (Sweden)

    marco trovatelli

    2017-05-01

    Full Text Available Abstract   Introductions Aim of EDEN 2020 project’s Milestone 5 is the development of a steerable catheter for CED system in glioblastoma therapy. The VET group is involved in realization and validation of the proper animal model. Materials and methods In this part of the study two fresh sheep’s head from the local slaughter were used. The heads were located into an ad hoc Frame system based on anatomical measures and CT images, producted by Renishaw plc partner in this project. The frame was adapted and every components were checked for the ex vivo validation tests. CT imaging was taken in Lodi at Università degli studi di Milano, Facoltà di Medicina Veterinaria, with CT scanner and MRI imaging was taken in La Cittadina, Cremona Results System validation was approved by the ex vivo trial. The frame system doesn’t compromise the imaging acquisition in MRI and CT systems. Every system components are functional to their aims. Discussion The Frame system is adapted to the sheep head. It is composed by elements able to lock the head during the imaging acquisition. Frame system is characterized by a support base helpings the animals to keep the head straight forward during imaging time, under general anesthesia. The design of these device support the airways anatomy, avoiding damaging or obstruction of airflows during anesthesia period. The role of elements like mouth bar and ovine head pins is to lock the head in a stable position during imaging acquisition; fixing is guaranteed by V shape head pins, that are arranged against the zygomatic arches. Lateral compression forces to the cranium, and the V shape pins avoid the vertical shifting of the head and any kind of rotations. (fig. 1

  10. An Australian population study of factors associated with MRI patterns in cerebral palsy.

    Science.gov (United States)

    Reid, Susan M; Dagia, Charuta D; Ditchfield, Michael R; Carlin, John B; Meehan, Elaine M; Reddihough, Dinah S

    2014-02-01

    The aim of this study was to describe the distribution of magnetic resonance imaging (MRI) patterns in a large population sample of children with cerebral palsy (CP) and to examine associations between MRI patterns, and antenatal and perinatal variables. Data were retrieved from the Victorian CP Register for 884 children (527 males, 357 females) born between 1999 and 2006. Postneonatal MRI was classified for 594 children. For 563 children (329 males, 234 females) for whom classification was to a single MRI pattern, the frequency of each variable was compared between patterns and with the population frequency. White matter injury was the most common MRI pattern (45%), followed by grey matter injury (14%), normal imaging (13%), malformations (10%), focal vascular insults (9%), and miscellaneous patterns (7%). Parity, birth gestation, level of neonatal care, Apgar score, and time to established respiration varied between MRI patterns (ppatterns, future exploration of causal pathways might be facilitated when performed in pathogenically defined groups. © 2013 Mac Keith Press.

  11. The biomechanics of running in athletes with previous hamstring injury: A case-control study.

    Science.gov (United States)

    Daly, C; Persson, U McCarthy; Twycross-Lewis, R; Woledge, R C; Morrissey, D

    2016-04-01

    Hamstring injury is prevalent with persistently high reinjury rates. We aim to inform hamstring rehabilitation by exploring the electromyographic and kinematic characteristics of running in athletes with previous hamstring injury. Nine elite male Gaelic games athletes who had returned to sport after hamstring injury and eight closely matched controls sprinted while lower limb kinematics and muscle activity of the previously injured biceps femoris, bilateral gluteus maximus, lumbar erector spinae, rectus femoris, and external oblique were recorded. Intergroup comparisons of muscle activation ratios and kinematics were performed. Previously injured athletes demonstrated significantly reduced biceps femoris muscle activation ratios with respect to ipsilateral gluteus maximus (maximum difference -12.5%, P = 0.03), ipsilateral erector spinae (maximum difference -12.5%, P = 0.01), ipsilateral external oblique (maximum difference -23%, P = 0.01), and contralateral rectus femoris (maximum difference -22%, P = 0.02) in the late swing phase. We also detected sagittal asymmetry in hip flexion (maximum 8°, P = 0.01), pelvic tilt (maximum 4°, P = 0.02), and medial rotation of the knee (maximum 6°, P = 0.03) effectively putting the hamstrings in a lengthened position just before heel strike. Previous hamstring injury is associated with altered biceps femoris associated muscle activity and potentially injurious kinematics. These deficits should be considered and addressed during rehabilitation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Design and rationale for examining neuroimaging genetics in ischemic stroke: The MRI-GENIE study.

    Science.gov (United States)

    Giese, Anne-Katrin; Schirmer, Markus D; Donahue, Kathleen L; Cloonan, Lisa; Irie, Robert; Winzeck, Stefan; Bouts, Mark J R J; McIntosh, Elissa C; Mocking, Steven J; Dalca, Adrian V; Sridharan, Ramesh; Xu, Huichun; Frid, Petrea; Giralt-Steinhauer, Eva; Holmegaard, Lukas; Roquer, Jaume; Wasselius, Johan; Cole, John W; McArdle, Patrick F; Broderick, Joseph P; Jimenez-Conde, Jordi; Jern, Christina; Kissela, Brett M; Kleindorfer, Dawn O; Lemmens, Robin; Lindgren, Arne; Meschia, James F; Rundek, Tatjana; Sacco, Ralph L; Schmidt, Reinhold; Sharma, Pankaj; Slowik, Agnieszka; Thijs, Vincent; Woo, Daniel; Worrall, Bradford B; Kittner, Steven J; Mitchell, Braxton D; Rosand, Jonathan; Golland, Polina; Wu, Ona; Rost, Natalia S

    2017-10-01

    To describe the design and rationale for the genetic analysis of acute and chronic cerebrovascular neuroimaging phenotypes detected on clinical MRI in patients with acute ischemic stroke (AIS) within the scope of the MRI-GENetics Interface Exploration (MRI-GENIE) study. MRI-GENIE capitalizes on the existing infrastructure of the Stroke Genetics Network (SiGN). In total, 12 international SiGN sites contributed MRIs of 3,301 patients with AIS. Detailed clinical phenotyping with the web-based Causative Classification of Stroke (CCS) system and genome-wide genotyping data were available for all participants. Neuroimaging analyses include the manual and automated assessments of established MRI markers. A high-throughput MRI analysis pipeline for the automated assessment of cerebrovascular lesions on clinical scans will be developed in a subset of scans for both acute and chronic lesions, validated against gold standard, and applied to all available scans. The extracted neuroimaging phenotypes will improve characterization of acute and chronic cerebrovascular lesions in ischemic stroke, including CCS subtypes, and their effect on functional outcomes after stroke. Moreover, genetic testing will uncover variants associated with acute and chronic MRI manifestations of cerebrovascular disease. The MRI-GENIE study aims to develop, validate, and distribute the MRI analysis platform for scans acquired as part of clinical care for patients with AIS, which will lead to (1) novel genetic discoveries in ischemic stroke, (2) strategies for personalized stroke risk assessment, and (3) personalized stroke outcome assessment.

  13. A technique to consider mismatches between fMRI and EEG/MEG sources for fMRI-constrained EEG/MEG source imaging: a preliminary simulation study

    International Nuclear Information System (INIS)

    Im, Chang-Hwan; Lee, Soo Yeol

    2006-01-01

    fMRI-constrained EEG/MEG source imaging can be a powerful tool in studying human brain functions with enhanced spatial and temporal resolutions. Recent studies on the combination of fMRI and EEG/MEG have suggested that fMRI prior information could be readily implemented by simply imposing different weighting factors to cortical sources overlapping with the fMRI activations. It has been also reported, however, that such a hard constraint may cause severe distortions or elimination of meaningful EEG/MEG sources when there are distinct mismatches between the fMRI activations and the EEG/MEG sources. If one wants to obtain the actual EEG/MEG source locations and uses the fMRI prior information as just an auxiliary tool to enhance focality of the distributed EEG/MEG sources, it is reasonable to weaken the strength of fMRI constraint when severe mismatches between fMRI and EEG/MEG sources are observed. The present study suggests an efficient technique to automatically adjust the strength of fMRI constraint according to the mismatch level. The use of the proposed technique rarely affects the results of conventional fMRI-constrained EEG/MEG source imaging if no major mismatch between the two modalities is detected; while the new results become similar to those of typical EEG/MEG source imaging without fMRI constraint if the mismatch level is significant. A preliminary simulation study using realistic EEG signals demonstrated that the proposed technique can be a promising tool to selectively apply fMRI prior information to EEG/MEG source imaging

  14. Studies of MRI relaxivities of gadolinium-labeled dendrons

    Science.gov (United States)

    Pan, Hongmu; Daniel, Marie-Christine

    2011-05-01

    In cancer detection, imaging techniques have a great importance in early diagnosis. The more sensitive the imaging technique and the earlier the tumor can be detected. Contrast agents have the capability to increase the sensitivity in imaging techniques such as magnetic resonance imaging (MRI). Until now, gadolinium-based contrast agents are mainly used for MRI, and show good enhancement. But improvement is needed for detection of smaller tumors at the earliest stage possible. The dendrons complexed with Gd(DOTA) were synthesized and evaluated as a new MRI contrast agent. The longitudinal and transverse relaxation effects were tested and compared with commercial drug Magnevist, Gd(DTPA).

  15. Aging affects the interaction between attentional control and source memory: an fMRI study.

    Science.gov (United States)

    Dulas, Michael R; Duarte, Audrey

    2014-12-01

    Age-related source memory impairments may be due, at least in part, to deficits in executive processes mediated by the PFC at both study and test. Behavioral work suggests that providing environmental support at encoding, such as directing attention toward item-source associations, may improve source memory and reduce age-related deficits in the recruitment of these executive processes. The present fMRI study investigated the effects of directed attention and aging on source memory encoding and retrieval. At study, participants were shown pictures of objects. They were either asked to attend to the objects and their color (source) or to their size. At test, participants determined if objects were seen before, and if so, whether they were the same color as previously. Behavioral results showed that direction of attention improved source memory for both groups; however, age-related deficits persisted. fMRI results revealed that, across groups, direction of attention facilitated medial temporal lobe-mediated contextual binding processes during study and attenuated right PFC postretrieval monitoring effects at test. However, persistent age-related source memory deficits may be related to increased recruitment of medial anterior PFC during encoding, indicative of self-referential processing, as well as underrecruitment of lateral anterior PFC-mediated relational processes. Taken together, this study suggests that, even when supported, older adults may fail to selectively encode goal-relevant contextual details supporting source memory performance.

  16. Rancidity inhibition study in frozen whole mackerel (scomber scombrus by a previous plant extract treatment.

    Directory of Open Access Journals (Sweden)

    Aubourg, Santiago P.

    2005-09-01

    Full Text Available The effect of flaxseeds (Linum usitatissimum on rancidity development in frozen whole mackerel (Scomber scombrus was studied. For it, fresh mackerel were dipped in flaxseeds aqueous extract during 60 min, frozen at –80 ºC during 24 hours and kept frozen (–20 ºC up to 12 months. Sampling was carried out on the initial material and at months 1, 3, 5, 7, 9 and 12 of frozen storage at –20 ºC. A parallel experiment with non treated fish was carried out in the same conditions. Rancidity development was measured by several biochemical indices (free fatty acids, peroxides, conjugated dienes and trienes, secondary oxidation products and lipoxygenase activity and complemented by the sensory analysis (skin, flesh odour, consistency and flesh appearance. As a result of the previous antioxidant treatment, peroxides showed to breakdown faster (pSe ha estudiado el efecto del lino (Linum usitatissimum en el desarrollo de rancidez en caballa entera congelada (Scomber scombrus. Para ello, caballas frescas fueron sumergidas en extractos acuosos de semillas de lino durante 60 min, congeladas a -80 ºC durante 24 h y mantenidas congeladas ( -20 ºC durante 12 meses. Se tomaron muestras del material inicial y tras 1, 3, 5, 7, 9 y 12 meses de congelación a -20 ºC . Un experimento paralelo con pescado no tratado fue llevado acabo en las mismas condiciones. El desarrollo de la rancidez fue medido por varios índices bioquímicos (ácidos grasos libres, peróxidos, dienos y trienos conjugados, productos secundarios de oxidación y actividad lipoxigenasa y completado con análisis sensorial (piel, olor de la carne, consistencia y apariencia de la carne. Como resultado del tratamiento antioxidante, los peróxidos se degradaron más rápidos (p < 0.05 después del mes 7, y por tanto, contenidos mayores (p < 0.05 de dienos y trienos conjugados pudieron ser detectados en el pescado tratado. El tratamiento antioxidante también condujo a un

  17. White matter lesions in watershed territories studied with MRI and parenchymography: a comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Minkner, K; Lovblad, K.O.; Yilmaz, H; Alimenti, A.; Delavelle, J; Ruefenacht, D.A. [University Hospital of Geneva, Department of Radiology, Geneva 14 (Switzerland); Sekoranja, L; Sztajzel, R [University Hospital of Geneva, Clinic of Neurology, Geneva 14 (Switzerland)

    2005-06-01

    Brain aging affects an increasing segment of the population and the role of chronic cerebrovascular disease is considered to be one of the main parameters involved. For this purpose we compared retrospectively MRI data with digitized subtraction angiography (DSA) data in a group of 50 patients focusing onto the watershed area of the carotid artery vascular territories. In order to evaluate the presence of white matter lesions (WML) in the hemispheric watershed areas, coronal fluid-attenuated inversion-recovery or axial T2 weighted MRI images of patients with symptomatic cerebrovascular insufficiency areas were compared with the capillary phase of DSA studies in anterior-posterior projection. Presence of cerebrovascular occlusive disease was evaluated on DSA using North American symptomatic carotid endarterectomy trial criteria and including evaluation of collateral vascular supply. Pathological MRI findings in the region of the watershed territories correlated overall in 66% of cases with a defect or delayed filling on DSA. In the case of asymmetrical MRI findings, there was a pathological finding of the capillary phase in the watershed area in 92% of DSA studies. Hypoperfusion in the capillary phase of the watershed area as seen on DSA correlated with the stenosis degree of the concerned carotid artery. Our findings suggest that asymmetrical findings of WML in the watershed areas as seen on MRI are caused by hemodynamic effect and a differentiation between small vessel disease and a consequence of distant stenosis may be possible under such conditions. (orig.)

  18. MRI Diagnosis of Intracranial Hemorrhage : Experimental and Clinical Studies

    International Nuclear Information System (INIS)

    Alemany Ripoll, Montserrat

    2003-02-01

    The purpose of this work was to improve the diagnosis of intracranial hemorrhage with MRI, and add knowledge about the newer sequences increasing in use to depict intra parenchymal bleeds, especially T2*-w GE sequences. We also compared the effect of magnetic field strengths. The sequences and field strengths were tested in animals. Then, the most effective technique was applied to patients with hematomas of different ages and with hematoma residuals. Occurrence of residuals of earlier, clinically silent, haemorrhages in patients with acute spontaneous hematoma or with suspected ischemic stroke were compared. Experimental studies: The MR detectability of small experimental haematomas in the brain and of blood in the cerebrospinal fluid (CSF) spaces of 30 rabbits was evaluated. MRI examinations were performed at determined intervals using different pulse sequences at two field strengths. The last MR images were compared to the formalin fixed brain sections and, in 16 rabbits, also to the histological findings. T2*-weighted GE sequences revealed all the intra parenchymal haematomas at 1.5 T: they were strongly hypointense. Their sizes became smaller but the signal patterns remained unchanged during the follow-up. The haematoma sizes and shapes corresponded well to gross pathology at acute and subacute stages. At chronic stage, the signal changes were larger than iron deposits. Blood in the CSF spaces was best detected at 1.5T with T2*-weighted GE sequences during the first 2 days. The FLAIR sequence often revealed blood in CSF spaces but not in the brain. SE sequences were rather insensitive. Imaging at 0.5 T was less effective than at 1.5 T. Clinical studies: All MR examinations on patients were performed at 1.5T, including T1- and T2-w SE, FLAIR, T2*-w GE sequences, and, occasionally, diffusion-w sequences. Sixty-six intra parenchymal hematomas were examined in the first clinical study. The hematomas were of different sizes and the ages varied from 8 hours to 3

  19. Cardiac MRI in patients with complex CHD following primary or secondary implantation of MRI-conditional pacemaker system.

    Science.gov (United States)

    Al-Wakeel, Nadya; O h-Ici, Darach; Schmitt, Katharina R; Messroghli, Daniel R; Riesenkampff, Eugénie; Berger, Felix; Kuehne, Titus; Peters, Bjoern

    2016-02-01

    In patients with CHD, cardiac MRI is often indicated for functional and anatomical assessment. With the recent introduction of MRI-conditional pacemaker systems, cardiac MRI has become accessible for patients with pacemakers. The present clinical study aims to evaluate safety, susceptibility artefacts, and image reading of cardiac MRI in patients with CHD and MRI-conditional pacemaker systems. Material and methods CHD patients with MRI-conditional pacemaker systems and a clinical need for cardiac MRI were examined with a 1.5-T MRI system. Lead function was tested before and after MRI. Artefacts and image readings were evaluated using a four-point grading scale. A total of nine patients with CHD (mean age 34.0 years, range 19.5-53.6 years) received a total of 11 cardiac MRI examinations. Owing to clinical indications, seven patients had previously been converted from conventional to MRI-conditional pacemaker systems. All MRI examinations were completed without adverse effects. Device testing immediately after MRI and at follow-up showed no alteration of pacemaker device and lead function. Clinical questions could be addressed and answered in all patients. Cardiac MRI can be performed safely with high certainty of diagnosis in CHD patients with MRI-conditional pacemaker systems. In case of clinically indicated lead and box changing, CHD patients with non-MRI-conditional pacemaker systems should be considered for complete conversion to MRI-conditional systems.

  20. Effect of Previous Irradiation on Vascular Thrombosis of Microsurgical Anastomosis: A Preclinical Study in Rats

    Science.gov (United States)

    Gallardo-Calero, Irene; López-Fernández, Alba; Romagosa, Cleofe; Vergés, Ramona; Aguirre-Canyadell, Marius; Soldado, Francisco; Velez, Roberto

    2016-01-01

    Background: The objective of the present investigation was to compare the effect of neoadjuvant irradiation on the microvascular anastomosis in cervical bundle using an experimental model in rats. Methods: One hundred forty male Sprague–Dawley rats were allocated into 4 groups: group I, control, arterial microanastomosis; group II, control, venous microanastomosis; group III, arterial microanastomosis with previous irradiation (20 Gy); and group IV, venous microanastomosis with previous irradiation (20 Gy). Clinical parameters, technical values of anastomosis, patency, and histopathological parameters were evaluated. Results: Irradiated groups (III and IV) and vein anastomosis groups (II and IV) showed significantly increased technical difficulties. Group IV showed significantly reduced patency rates (7/35) when compared with the control group (0/35). Radiotherapy significantly decreased the patency rates of the vein (7/35) when compared with the artery (1/35). Groups III and IV showed significantly reduced number of endothelial cells and also showed the presence of intimal thickening and adventitial fibrosis as compared with the control group. Conclusion: Neoadjuvant radiotherapy reduces the viability of the venous anastomosis in a preclinical rat model with a significant increase in the incidence of vein thrombosis. PMID:27975009

  1. Individualized prediction of illness course at the first psychotic episode: a support vector machine MRI study.

    LENUS (Irish Health Repository)

    Mourao-Miranda, J

    2012-05-01

    To date, magnetic resonance imaging (MRI) has made little impact on the diagnosis and monitoring of psychoses in individual patients. In this study, we used a support vector machine (SVM) whole-brain classification approach to predict future illness course at the individual level from MRI data obtained at the first psychotic episode.

  2. Contrast enhancement by lipid-based MRI contrast agents in mouse atherosclerotic plaques; a longitudinal study

    NARCIS (Netherlands)

    den Adel, Brigit; van der Graaf, Linda M.; Que, Ivo; Strijkers, Gustav J.; Löwik, Clemens W.; Poelmann, Robert E.; van der Weerd, Louise

    2013-01-01

    The use of contrast-enhanced MRI to enable in vivo specific characterization of atherosclerotic plaques is increasing. In this study the intrinsic ability of two differently sized gadolinium-based contrast agents to enhance atherosclerotic plaques in ApoE(-/-) mice was evaluated with MRI. We

  3. Ankle brachial index, MRI markers and cognition: The Epidemiology of Dementia in Singapore study.

    Science.gov (United States)

    Shaik, Muhammad Amin; Venketasubramanian, Narayanaswamy; Cheng, Ching-Yu; Wong, Tien Yin; Vrooman, Henri; Ikram, Mohammad Kamran; Hilal, Saima; Chen, Christopher

    2017-08-01

    Previous studies showed an independent association of low ankle-brachial index (ABI) with cognitive impairment. However, the association between low ABI and cognition in the presence of both cerebrovascular disease (CeVD) and neurodegeneration is lacking. We aimed at investigating a) the association of low ABI with markers of CeVD and cortical thickness, and b) whether the association of low ABI with cognition is influenced by these markers. Data was drawn from the Epidemiology of Dementia In Singapore (EDIS) study where all participants (n = 832) underwent neuropsychological tests and 3T brain magnetic resonance imaging (MRI) to assess CeVD markers as well as cortical thicknesses. Cognitive function was expressed as a global composite z-score and domain-specific z-scores of a comprehensive neuropsychological battery. Multivariate analyses showed low ABI to be independently associated with intracranial stenosis [odds ratios (OR): 1.51; 95% confidence interval (CI):1.23-1.87] and lacunar infarcts [OR: 1.29; 95% CI: 1.06-1.57]. A low ABI was also independently associated with smaller cortical thickness globally [β: 0.09; 95% CI: 0.27-0.16] as well as with the limbic [β: 0.10; 95% CI: 0.03-0.17], temporal [β: 0.09; 95% CI: 0.02-0.15], parietal [β: 0.08; 95% CI: 0.02-0.15], and occipital [β: 0.09; 95% CI: 0.03-0.16] lobes. Low ABI was associated with worse performance in verbal memory [β: 0.06; 95% CI: 0.01-0.12], which became attenuated in the presence of MRI markers. A low ABI is associated with MRI markers, and affects cognition in the presence of CeVD and neurodegeneration. Atherosclerosis should be targeted as a potentially modifiable risk factor to prevent cognitive disorders. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Brain structure in women at risk of postpartum psychosis: an MRI study.

    Science.gov (United States)

    Fusté, Montserrat; Pauls, Astrid; Worker, Amanda; Reinders, Antje A T S; Simmons, Andrew; Williams, Steven C R; Haro, Josep M; Hazelgrove, Kate; Pawlby, Susan; Conroy, Susan; Vecchio, Costanza; Seneviratne, Gertrude; Pariante, Carmine M; Mehta, Mitul A; Dazzan, Paola

    2017-12-18

    Postpartum psychosis (PP) is the most severe psychiatric disorder associated with childbirth. The risk of PP is very high in women with a history of bipolar affective disorder or schizoaffective disorder. However, the neurobiological basis of PP remains poorly understood and no study has evaluated brain structure in women at risk of, or with, PP. We performed a cross-sectional study of 256 women at risk of PP and 21 healthy controls (HC) in the same postpartum period. Among women at risk, 11 who developed a recent episode of PP (PPE) (n = 2 with lifetime bipolar disorder; n = 9 psychotic disorder not otherwise specified) and 15 at risk women who did not develop an episode of PP (NPPE) (n = 10 with lifetime bipolar disorder; n = 1 with schizoaffective disorder; n = 1 with a history of PP in first-degree family member; n = 3 with previous PP). We obtained T1-weighted MRI scans at 3T and examined regional gray matter volumes with voxel-based morphometry and cortical thickness and surface area with Freesurfer. Women with PPE showed smaller anterior cingulate gyrus, superior temporal gyrus and parahippocampal gyrus compared to NPPE women. These regions also showed decreased surface area. Moreover, the NPPE group showed a larger superior and inferior frontal gyrus volume than the HC. These results should be interpreted with caution, as there were between-group differences in terms of duration of illness and interval between delivery and MRI acquisition. Nevertheless, these are the first findings to suggest that MRI can provide information on brain morphology that characterize those women at risk of PP more likely to develop an episode after childbirth.

  5. The OMERACT MRI inflammatory arthritis group: advances and future research priorities

    DEFF Research Database (Denmark)

    Conaghan, Philip G; Bird, Paul; McQueen, Fiona

    2009-01-01

    The OMERACT magnetic resonance imaging (MRI) in inflammatory arthritis group previously developed the rheumatoid arthritis MRI score (RAMRIS) for use in clinical studies, evaluated the use of extremity MRI, and initiated development of a psoriatic arthritis MRI score (PsAMRIS). At OMERACT 9 the g...

  6. Are autobiographical memories inherently social? Evidence from an fMRI study.

    Directory of Open Access Journals (Sweden)

    Linda Wilbers

    Full Text Available The story of our lifetime - our narrative self - is constructed from our autobiographical memories. A central claim of social psychology is that this narrative self is inherently social: When we construct our lives, we do so in a real or imagined interaction. This predicts that self-referential processes which are involved in recall of autobiographical memories overlap with processes involved in social interactions. Indeed, previous functional MRI studies indicate that regions in the medial prefrontal cortex (mPFC are activated during autobiographical memory recall and virtual communication. However, no fMRI study has investigated recall of autobiographical memories in a real-life interaction. We developed a novel paradigm in which participants overtly reported self-related and other-related memories to an experimenter, whose non-verbal reactions were being filmed and online displayed to the participants in the scanner. We found that recall of autobiographical vs. non-autobiographical memories was associated with activation of the mPFC, as was recall in the social as compared to a non-social control condition; however, both contrasts involved different non-overlapping regions within the mPFC. These results indicate that self-referential processes involved in autobiographical memory recall are different from processes supporting social interactions, and argue against the hypothesis that autobiographical memories are inherently social.

  7. Assessment of lexical semantic judgment abilities in alcohol-dependent subjects: an fMRI study.

    Science.gov (United States)

    Bagga, D; Singh, N; Modi, S; Kumar, P; Bhattacharya, D; Garg, M L; Khushu, S

    2013-12-01

    Neuropsychological studies have shown that alcohol dependence is associated with neurocognitive deficits in tasks requiring memory, perceptual motor skills, abstraction and problem solving, whereas language skills are relatively spared in alcoholics despite structural abnormalities in the language-related brain regions. To investigate the preserved mechanisms of language processing in alcohol-dependents, functional brain imaging was undertaken in healthy controls (n=18) and alcohol-dependents (n=16) while completing a lexical semantic judgment task in a 3 T MR scanner. Behavioural data indicated that alcohol-dependents took more time than controls for performing the task but there was no significant difference in their response accuracy. fMRI data analysis revealed that while performing the task, the alcoholics showed enhanced activations in left supramarginal gyrus, precuneus bilaterally, left angular gyrus, and left middle temporal gyrus as compared to control subjects. The extensive activations observed in alcoholics as compared to controls suggest that alcoholics recruit additional brain areas to meet the behavioural demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting compensatory mechanisms for the execution of task for showing an equivalent performance or decreased neural efficiency of relevant brain networks. However, on direct comparison of the two groups, the results did not survive correction for multiple comparisons; therefore, the present findings need further exploration.

  8. A study comparing MRI with clinical examinations on wrists with rheumatoid arthritis

    International Nuclear Information System (INIS)

    Wang Jun; Niu Jinliang; Xie Weina; Song Zhizhen; Zheng Jie; Ma Qiang

    2004-01-01

    Objective: To study the appearances of rheumatoid arthritis (RA) on MRI, and compare MRI with clinical examinations on wrists with RA. Methods: Fifty patients, fulfilled 1987 American Rheumatism Association (ARA) revised criteria, and 10 age-matched healthy controls entered the study. T 1 -weighted spin echo, short time inversion recovery (STIR) of both wrists, gadolinium contrast material-enhanced sequences of dominant wrists were performed in the coronal planes. MRl, plain wrist radiographs, clinical date, including swollen joint, patient global assessment (AIMS), and laboratory examinations including ESR, RF, APF, and AKA were obtained at the same time. Functional disability was assessed using the Health Assessment Questionnaire Disability Score. Results: In 50 patients, all had pannus on MRI of wrists, 38 patients had enhanced signal intensity for pannus, 21 patients had bone marrow edema, 37 patients had joint effusion, and 37 patients had bone erosions. There were significant difference in the ESR, HAQ, AIMS as well as swollen joint count between patients with bone marrow edema and patients without bone marrow edema (P 2 =5.06, P=0.025; χ 2 =5.59, P=0.018). Number of patients with MRI erosion of wrists was associated with the number of patients without MRI bone marrow edema of wrists (χ 2 =5.11, P=0.024). Conclusion: MRI can find the appearances of wrists with RA. Comparing MRI with clinical examinations on wrists with RA, authors can assess and evaluate the role of MRI on RA

  9. fMRI-adaptation studies of viewpoint tuning in the extrastriate and fusiform body areas.

    Science.gov (United States)

    Taylor, John C; Wiggett, Alison J; Downing, Paul E

    2010-03-01

    People are easily able to perceive the human body across different viewpoints, but the neural mechanisms underpinning this ability are currently unclear. In three experiments, we used functional MRI (fMRI) adaptation to study the view-invariance of representations in two cortical regions that have previously been shown to be sensitive to visual depictions of the human body--the extrastriate and fusiform body areas (EBA and FBA). The BOLD response to sequentially presented pairs of bodies was treated as an index of view invariance. Specifically, we compared trials in which the bodies in each image held identical poses (seen from different views) to trials containing different poses. EBA and FBA adapted to identical views of the same pose, and both showed a progressive rebound from adaptation as a function of the angular difference between views, up to approximately 30 degrees. However, these adaptation effects were eliminated when the body stimuli were followed by a pattern mask. Delaying the mask onset increased the response (but not the adaptation effect) in EBA, leaving FBA unaffected. We interpret these masking effects as evidence that view-dependent fMRI adaptation is driven by later waves of neuronal responses in the regions of interest. Finally, in a whole brain analysis, we identified an anterior region of the left inferior temporal sulcus (l-aITS) that responded linearly to stimulus rotation, but showed no selectivity for bodies. Our results show that body-selective cortical areas exhibit a similar degree of view-invariance as other object selective areas--such as the lateral occipitotemporal area (LO) and posterior fusiform gyrus (pFs).

  10. The Neural Basis of Typewriting: A Functional MRI Study.

    Science.gov (United States)

    Higashiyama, Yuichi; Takeda, Katsuhiko; Someya, Yoshiaki; Kuroiwa, Yoshiyuki; Tanaka, Fumiaki

    2015-01-01

    To investigate the neural substrate of typewriting Japanese words and to detect the difference between the neural substrate of typewriting and handwriting, we conducted a functional magnetic resonance imaging (fMRI) study in 16 healthy volunteers. All subjects were skillful touch typists and performed five tasks: a typing task, a writing task, a reading task, and two control tasks. Three brain regions were activated during both the typing and the writing tasks: the left superior parietal lobule, the left supramarginal gyrus, and the left premotor cortex close to Exner's area. Although typing and writing involved common brain regions, direct comparison between the typing and the writing task revealed greater left posteromedial intraparietal cortex activation in the typing task. In addition, activity in the left premotor cortex was more rostral in the typing task than in the writing task. These findings suggest that, although the brain circuits involved in Japanese typewriting are almost the same as those involved in handwriting, there are brain regions that are specific for typewriting.

  11. MRI study of normal pituitary glands in stage of puberty

    International Nuclear Information System (INIS)

    Lin Guangwu; Zhang Tao; Yang Ning; Cai Feng; Shi Yifan; Deng Jieying; Zhang Luodong; Jiang Yayun

    2005-01-01

    Objective: To study the changes of shape, size and signal intensity of normal pituitary glands in adolescents and to correlate the size and shape of normal pituitary glands with the age, height and weight in stage of puberty. Methods: One hundred and fifty-five cases of MRI data of pituitary glands in normal adolescents range from 6.0 year to 18.9 year were used. Using high-field 1.5T MR scanner, the appearances of pituitary glands in 152 normal adolescents were analyzed on T 1 WI in standard median sagittal and coronal plane. Results: Three groups quantitative data of size, shape and single intensity changes of normal pituitary glands were obtained, which were divided into 6- m =0.74, t=3.624, P=0.004; r f =0.94, t=9.562, P=0.000), however, it was not markedly correlated with the height and weight (P>0.05). Conclusion: Obvious changes of the size and shape of pituitary glands were found in health adolescents. The pituitary glands manifest physiologic hypertrophy with more convex of upper border when age increased in stage of puberty. The spherical appearance of the pituitary glands is a normal developmental feature and should not warrant clinical investigation for the presence of an underlying micro-adenoma in teenage females. (authors)

  12. The Neural Basis of Typewriting: A Functional MRI Study.

    Directory of Open Access Journals (Sweden)

    Yuichi Higashiyama

    Full Text Available To investigate the neural substrate of typewriting Japanese words and to detect the difference between the neural substrate of typewriting and handwriting, we conducted a functional magnetic resonance imaging (fMRI study in 16 healthy volunteers. All subjects were skillful touch typists and performed five tasks: a typing task, a writing task, a reading task, and two control tasks. Three brain regions were activated during both the typing and the writing tasks: the left superior parietal lobule, the left supramarginal gyrus, and the left premotor cortex close to Exner's area. Although typing and writing involved common brain regions, direct comparison between the typing and the writing task revealed greater left posteromedial intraparietal cortex activation in the typing task. In addition, activity in the left premotor cortex was more rostral in the typing task than in the writing task. These findings suggest that, although the brain circuits involved in Japanese typewriting are almost the same as those involved in handwriting, there are brain regions that are specific for typewriting.

  13. MRI study of degenerative process in multiple system atrophy

    International Nuclear Information System (INIS)

    Yagishita, Toshiyuki; Kojima, Shigeyuki; Hirayama, Keizo

    1995-01-01

    The characteristic morphological changes of the brainstem and cerebellar regions of multiple system atrophy (MSA) were studied by MRI in varing subtypes, that is olivoponto cerebellar atrophy (OPCA: 23 cases), striatonigral degeneration (SND: 7 cases) and Shy-Drager's syndrome (SDS: 9 cases). OPCA was characterized by atrophy of the entire regions of the brainstem and the cerebellum. SND and SDS tended to show atrophy similar in type but lessin extent to OPCA. The common lesions in MSA were atrophy of the pontine base and cerebellum, and dilation of the fourth ventricle. Atrophy of the pontine base was more dominant in the inferior part than in the superior part, and cerebellar atrophy was more dominant in the superior part than in the inferior part, indicating that degeneration of the pontocerebellar pathway proceeds principally along fibers connecting the inferior part of the pons and the superior part of the cerebellum. Dilation of the fourth ventricle indicated atrophy of the middle cerebellar peduncle. In almost all the cases of OPCA and about a half the cases of SND and SDS, the pontine base and the middle cerebellar peduncle appeared as high signal intensity on T 2 weighted image and as low intensity on T 1 , suggesting degeneration and demyelination. In a few cases of OPCA, the dorsolateral part of the putamen were demonstrated as low signal intensity on T 2 weighted image. (author)

  14. MRI study of degenerative process in multiple system atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Yagishita, Toshiyuki; Kojima, Shigeyuki; Hirayama, Keizo [Chiba Univ. (Japan). School of Medicine

    1995-02-01

    The characteristic morphological changes of the brainstem and cerebellar regions of multiple system atrophy (MSA) were studied by MRI in varing subtypes, that is olivoponto cerebellar atrophy (OPCA: 23 cases), striatonigral degeneration (SND: 7 cases) and Shy-Drager`s syndrome (SDS: 9 cases). OPCA was characterized by atrophy of the entire regions of the brainstem and the cerebellum. SND and SDS tended to show atrophy similar in type but lessin extent to OPCA. The common lesions in MSA were atrophy of the pontine base and cerebellum, and dilation of the fourth ventricle. Atrophy of the pontine base was more dominant in the inferior part than in the superior part, and cerebellar atrophy was more dominant in the superior part than in the inferior part, indicating that degeneration of the pontocerebellar pathway proceeds principally along fibers connecting the inferior part of the pons and the superior part of the cerebellum. Dilation of the fourth ventricle indicated atrophy of the middle cerebellar peduncle. In almost all the cases of OPCA and about a half the cases of SND and SDS, the pontine base and the middle cerebellar peduncle appeared as high signal intensity on T{sub 2} weighted image and as low intensity on T{sub 1}, suggesting degeneration and demyelination. In a few cases of OPCA, the dorsolateral part of the putamen were demonstrated as low signal intensity on T{sub 2} weighted image. (author).

  15. Usefulness of Integrated PET/MRI in Head and Neck Cancer: A Preliminary Study

    International Nuclear Information System (INIS)

    Lee, Soo Jin; Seo, Hyo Jung; Cheon, Gi Jeong; Kim, Ji Hoon; Kim, E. Edmund; Kang, Keon Wook; Paeng, Jin Chul; Chung, Junekey; Lee, Dong Soo

    2014-01-01

    The new modality of an integrated positron emission tomography/magnetic resonance imaging (PET/MRI) has recently been introduced but not validated. Our objective was to evaluate clinical performance of 18 F-fluoro-2-deoxyglucose ( 18 F-FDG) PET/MRI in patients with head and neck cancer. This retrospective study was conducted between January 2013 and February 2013. Ten patients (eight men, two women; mean age, 61.4±13.4 years) with histologically proven head and neck tumors were enrolled.Whole-body PET/MRI and regional positron emission tomography (PET) with dedicated MRI were sequentially obtained. Maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume, total lesion glycolysis and contrast enhancement were analyzed. A total of ten whole-body positron emission tomography (PET), ten regional positron emission tomography (PET), ten dedicated MRI and ten regional PET/gadolinium-enhanced T1-weighted (Gd)-MRI images were analyzed for initial staging. Two nuclear medicine physicians analyzed positron emission tomography (PET) and PET/MRI with a consensus. One radiologist analyzed dedicated MRI. The primary lesions and number of metastatic lymph nodes analyzed from each image were compared. Eight patients were diagnosed with head and neck cancer (one tongue cancer, four tonsillar cancers, one nasopharyngeal cancer and two hypopharyngeal cancers) by histological diagnosis. Two benign tumors (pleomorphic adenoma and Warthin tumor) were diagnosed with surgical operation. Whole-body positron emission tomography (PET) and regional positron emission tomography (PET) attenuated by MRI showed good image quality for the lesion detection. Whole-body positron emission tomography (PET) and regional positron emission tomography (PET) detected ten primary sites and compensated for a missed lesion on dedicated MRI. A discordant number of suspicious lymph node metastases was noted according to the different images; 22, 16, 39 and 40 in the whole-body positron

  16. Effect of patient age on accuracy of primary MRI signs of long head of biceps tearing and instability in the shoulder. An MRI-arthroscopy correlation study

    Energy Technology Data Exchange (ETDEWEB)

    Borrero, Camilo G.; Costello, Joanna; Vyas, Dharmesh [University of Pittsburgh Medical Center, Pittsburgh, PA (United States); Bertolet, Marnie [University of Pittsburgh School of Medicine, Pittsburgh, PA (United States)

    2018-02-15

    To determine the effect of patient age on the accuracy of primary MRI signs of long head of biceps (LHB) tendon tearing and instability in the shoulder using arthroscopy as a reference standard. Subjects with MRI studies and subsequent arthroscopy documenting LHB tendon pathology were identified and organized into three age groups (18-40, 41-60, 61-87). Normal and tendinopathic tendons were labeled grade 0, partial tears grade 1 and full tears grade 2. Two radiologists blinded to arthroscopic data graded MRI studies independently. Prevalence of disease, MRI accuracy for outcomes of interest, and inter-reader agreement were calculated. Eighty-nine subjects fulfilled inclusion criteria with 36 grade 0, 36 grade 1 and 17 grade 2 tendons found at arthroscopy. MRI sensitivity, regardless of age, ranged between 67-86% for grade 0, 72-94% for grade 1 and 82-94% for grade 2 tendons. Specificity ranged between 83-96% for grade 0, 75-85% for grade 1 and 99-100% for grade 2 tendons. MRI accuracy for detection of each LHB category was calculated for each age group. MRI was found to be least sensitive for grade 0 and 1 LHB tendons in the middle-aged group with sensitivity between 55-85% for grade 0 and 53-88% for grade 1 tendons. Agreement between MRI readers was moderate with an unweighted kappa statistic of 62%. MRI accuracy was moderate to excellent and agreement between MRI readers was moderate. MRI appears to be less accurate in characterizing lower grades of LHB tendon disease in middle-aged subjects. (orig.)

  17. Late preterm birth and previous cesarean section: a population-based cohort study.

    Science.gov (United States)

    Yasseen Iii, Abdool S; Bassil, Kate; Sprague, Ann; Urquia, Marcelo; Maguire, Jonathon L

    2018-02-21

    Late preterm birth (LPB) is increasingly common and associated with higher morbidity and mortality than term birth. Yet, little is known about the influence of previous cesarean section (PCS) and the occurrence of LPB in subsequent pregnancies. We aim to evaluate this association along with the potential mediation by cesarean sections in the current pregnancy. We use population-based birth registry data (2005-2012) to establish a cohort of live born singleton infants born between 34 and 41 gestational weeks to multiparous mothers. PCS was the primary exposure, LPB (34-36 weeks) was the primary outcome, and an unplanned or emergency cesarean section in the current pregnancy was the potential mediator. Associations were quantified using propensity weighted multivariable Poisson regression, and mediating associations were explored using the Baron-Kenny approach. The cohort included 481,531 births, 21,893 (4.5%) were LPB, and 119,983 (24.9%) were predated by at least one PCS. Among mothers with at least one PCS, 6307 (5.26%) were LPB. There was increased risk of LPB among women with at least one PCS (adjusted Relative Risk (aRR): 1.20 (95%CI [1.16, 1.23]). Unplanned or emergency cesarean section in the current pregnancy was identified as a strong mediator to this relationship (mediation ratio = 97%). PCS was associated with higher risk of LPB in subsequent pregnancies. This may be due to an increased risk of subsequent unplanned or emergency preterm cesarean sections. Efforts to minimize index cesarean sections may reduce the risk of LPB in subsequent pregnancies.

  18. MRI study of the brain in aged volunteers

    International Nuclear Information System (INIS)

    Kasahara, Hiroo; Tanno, Munehiko; Yamada, Hideo; Endoh, Kazuo; Kobayashi, Mitsuru; Karasawa, Akihide.

    1993-01-01

    In order to characterize age-related and chronological changes of the brain, longitudinal studies of aged volunteers were conducted using computed tomography since 1982. The present paper discusses correlations between brain function and findings of MR images which were obtained using a 1.5 T superconductive MR instrument since 1989. A total of 118 volunteers aged 60 to 88 years old with a mean age of 75.0±6.7 participated in the study, which consisted of MRI, EEG recording, the Benton Visual Retention Test and a medical interview. Subjects with a past history or clinical evidence of CVD, head trauma or dementia were excluded from the study. Incidence of T 2 high signal intensity lesions increased with age. Some showing T 1 low signal intensity in the same lesion were considered to be lacunar infarction, over all incidence of which was 24.6%. Numbers of correct responses on the BVRT showed a negative correlation with numbers of T 2 high signal intensity lesions. Although the aged volunteers in the present study could achieve all activity of daily living without any trouble, high cortical function evaluated by visuoperceptual performance of BVRT was somewhat disturbed in participants with multiple T 2 high signal intensity lesions. Brain atrophy seems to be more advanced in groups with T 2 hyper intensity lesions than in the group without them. These findings may support the notion that T 2 high signal intensity lesions are not merely an index of aging but pathologic lesions accompanied with senescence, although further studies including clinico-pathological correlation are necessary to establish this concept. (author)

  19. Decision Making under Risk Condition in Patients with Parkinson’s Disease: A Behavioural and fMRI Study

    Directory of Open Access Journals (Sweden)

    Kirsten Labudda

    2010-01-01

    Full Text Available We aimed to study whether previously described impairment in decision making under risky conditions in patients with Parkinson's disease (PD is affected by deficits in using information about potential incentives or by processing feedback (in terms of fictitious gains and losses following each decision. Additionally, we studied whether the neural correlates of using explicit information in decision making under risk differ between PD patients and healthy subjects. We investigated ten cognitively intact PD patients and twelve healthy subjects with the Game of Dice Task (GDT to assess risky decision making, and with an fMRI paradigm to analyse the neural correlates of information integration in the deliberative decision phase. Behaviourally, PD patients showed selective impairment in the GDT but not on the fMRI task that did not include a feedback component. Healthy subjects exhibited lateral prefrontal, anterior cingulate and parietal activations when integrating decision-relevant information. Despite similar behavioural patterns on the fMRI task, patients exhibited reduced parietal activation. Behavioural results suggest that PD patients’ deficits in risky decision making are dominated by impaired feedback utilization not compensable by intact cognitive functions. Our fMRI results suggest similarities but also differences in neural correlates when using explicit information for the decision process, potentially indicating different strategy application even if the interfering feedback component is excluded.

  20. Altered regional homogeneity in pediatric bipolar disorder during manic state: a resting-state fMRI study.

    Directory of Open Access Journals (Sweden)

    Qian Xiao

    Full Text Available UNLABELLED: Pediatric bipolar disorder (PBD is a severely debilitating illness, which is characterized by episodes of mania and depression separated by periods of remission. Previous fMRI studies investigating PBD were mainly task-related. However, little is known about the abnormalities in PBD, especially during resting state. Resting state brain activity measured by fMRI might help to explore neurobiological biomarkers of the disorder. METHODS: Regional homogeneity (ReHo was examined with resting-state fMRI (RS-fMRI on 15 patients with PBD in manic state, with 15 age-and sex-matched healthy youth subjects as controls. RESULTS: Compared with the healthy controls, the patients with PBD showed altered ReHo in the cortical and subcortical structures. The ReHo measurement of the PBD group was negatively correlated with the score of Young Mania Rating Scale (YMRS in the superior frontal gyrus. Positive correlations between the ReHo measurement and the score of YMRS were found in the hippocampus and the anterior cingulate cortex in the PBD group. CONCLUSIONS: Altered regional brain activity is present in patients with PBD during manic state. This study presents new evidence for abnormal ventral-affective and dorsal-cognitive circuits in PBD during resting state and may add fresh insights into the pathophysiological mechanisms underlying PBD.

  1. Phase III Study of Cabozantinib in Previously Treated Metastatic Castration-Resistant Prostate Cancer: COMET-1.

    Science.gov (United States)

    Smith, Matthew; De Bono, Johann; Sternberg, Cora; Le Moulec, Sylvestre; Oudard, Stéphane; De Giorgi, Ugo; Krainer, Michael; Bergman, Andries; Hoelzer, Wolfgang; De Wit, Ronald; Bögemann, Martin; Saad, Fred; Cruciani, Giorgio; Thiery-Vuillemin, Antoine; Feyerabend, Susan; Miller, Kurt; Houédé, Nadine; Hussain, Syed; Lam, Elaine; Polikoff, Jonathan; Stenzl, Arnulf; Mainwaring, Paul; Ramies, David; Hessel, Colin; Weitzman, Aaron; Fizazi, Karim

    2016-09-01

    Cabozantinib is an inhibitor of kinases, including MET and vascular endothelial growth factor receptors, and has shown activity in men with previously treated metastatic castration-resistant prostate cancer (mCRPC). This blinded phase III trial compared cabozantinib with prednisone in patients with mCRPC. Men with progressive mCRPC after docetaxel and abiraterone and/or enzalutamide were randomly assigned at a two-to-one ratio to cabozantinib 60 mg once per day or prednisone 5 mg twice per day. The primary end point was overall survival (OS). Bone scan response (BSR) at week 12 as assessed by independent review committee was the secondary end point; radiographic progression-free survival (rPFS) and effects on circulating tumor cells (CTCs), bone biomarkers, serum prostate-specific antigen (PSA), and symptomatic skeletal events (SSEs) were exploratory assessments. A total of 1,028 patients were randomly assigned to cabozantinib (n = 682) or prednisone (n = 346). Median OS was 11.0 months with cabozantinib and 9.8 months with prednisone (hazard ratio, 0.90; 95% CI, 0.76 to 1.06; stratified log-rank P = .213). BSR at week 12 favored cabozantinib (42% v 3%; stratified Cochran-Mantel-Haenszel P < .001). rPFS was improved in the cabozantinib group (median, 5.6 v 2.8 months; hazard ratio, 0.48; 95% CI, 0.40 to 0.57; stratified log-rank P < .001). Cabozantinib was associated with improvements in CTC conversion, bone biomarkers, and post-random assignment incidence of SSEs but not PSA outcomes. Grade 3 to 4 adverse events and discontinuations because of adverse events were higher with cabozantinib than with prednisone (71% v 56% and 33% v 12%, respectively). Cabozantinib did not significantly improve OS compared with prednisone in heavily treated patients with mCRPC and progressive disease after docetaxel and abiraterone and/or enzalutamide. Cabozantinib had some activity in improving BSR, rPFS, SSEs, CTC conversions, and bone biomarkers but not PSA outcomes. © 2016 by

  2. Cerebral migration of intraocular silicone oil: an MRI study

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Milea, Dan; Løgager, Vibeke

    2011-01-01

    for retinal detachment. Methods: Nineteen patients included in this study were referred for silicone oil removal after uncomplicated retinal detachment surgery using internal silicone oil tamponade. Patients with a previous history of intraocular silicone oil, glaucoma or optic pit were excluded. After...

  3. Modality Specific Cerebro-Cerebellar Activations in Verbal Working Memory: An fMRI Study

    Directory of Open Access Journals (Sweden)

    Matthew P. Kirschen

    2010-01-01

    Full Text Available Verbal working memory (VWM engages frontal and temporal/parietal circuits subserving the phonological loop, as well as, superior and inferior cerebellar regions which have projections from these neocortical areas. Different cerebro-cerebellar circuits may be engaged for integrating aurally- and visually-presented information for VWM. The present fMRI study investigated load (2, 4, or 6 letters and modality (auditory and visual dependent cerebro-cerebellar VWM activation using a Sternberg task. FMRI revealed modality-independent activations in left frontal (BA 6/9/44, insular, cingulate (BA 32, and bilateral inferior parietal/supramarginal (BA 40 regions, as well as in bilateral superior (HVI and right inferior (HVIII cerebellar regions. Visual presentation evoked prominent activations in right superior (HVI/CrusI cerebellum, bilateral occipital (BA19 and left parietal (BA7/40 cortex while auditory presentation showed robust activations predominately in bilateral temporal regions (BA21/22. In the cerebellum, we noted a visual to auditory emphasis of function progressing from superior to inferior and from lateral to medial regions. These results extend our previous findings of fMRI activation in cerebro-cerebellar networks during VWM, and demonstrate both modality dependent commonalities and differences in activations with increasing memory load.

  4. Modality Specific Cerebro-Cerebellar Activations in Verbal Working Memory: An fMRI Study

    Science.gov (United States)

    Kirschen, Matthew P.; Chen, S. H. Annabel; Desmond, John E.

    2010-01-01

    Verbal working memory (VWM) engages frontal and temporal/parietal circuits subserving the phonological loop, as well as, superior and inferior cerebellar regions which have projections from these neocortical areas. Different cerebro-cerebellar circuits may be engaged for integrating aurally- and visually-presented information for VWM. The present fMRI study investigated load (2, 4, or 6 letters) and modality (auditory and visual) dependent cerebro-cerebellar VWM activation using a Sternberg task. FMRI revealed modality-independent activations in left frontal (BA 6/9/44), insular, cingulate (BA 32), and bilateral inferior parietal/supramarginal (BA 40) regions, as well as in bilateral superior (HVI) and right inferior (HVIII) cerebellar regions. Visual presentation evoked prominent activations in right superior (HVI/CrusI) cerebellum, bilateral occipital (BA19) and left parietal (BA7/40) cortex while auditory presentation showed robust activations predominately in bilateral temporal regions (BA21/22). In the cerebellum, we noted a visual to auditory emphasis of function progressing from superior to inferior and from lateral to medial regions. These results extend our previous findings of fMRI activation in cerebro-cerebellar networks during VWM, and demonstrate both modality dependent commonalities and differences in activations with increasing memory load. PMID:20714061

  5. Learning by strategies and learning by drill--evidence from an fMRI study.

    Science.gov (United States)

    Delazer, M; Ischebeck, A; Domahs, F; Zamarian, L; Koppelstaetter, F; Siedentopf, C M; Kaufmann, L; Benke, T; Felber, S

    2005-04-15

    The present fMRI study investigates, first, whether learning new arithmetic operations is reflected by changing cerebral activation patterns, and second, whether different learning methods lead to differential modifications of brain activation. In a controlled design, subjects were trained over a week on two new complex arithmetic operations, one operation trained by the application of back-up strategies, i.e., a sequence of arithmetic operations, the other by drill, i.e., by learning the association between the operands and the result. In the following fMRI session, new untrained items, items trained by strategy and items trained by drill, were assessed using an event-related design. Untrained items as compared to trained showed large bilateral parietal activations, with the focus of activation along the right intraparietal sulcus. Further foci of activation were found in both inferior frontal gyri. The reverse contrast, trained vs. untrained, showed a more focused activation pattern with activation in both angular gyri. As suggested by the specific activation patterns, newly acquired expertise was implemented in previously existing networks of arithmetic processing and memory. Comparisons between drill and strategy conditions suggest that successful retrieval was associated with different brain activation patterns reflecting the underlying learning methods. While the drill condition more strongly activated medial parietal regions extending to the left angular gyrus, the strategy condition was associated to the activation of the precuneus which may be accounted for by visual imagery in memory retrieval.

  6. Incremental diagnostic value of targeted biopsy using mpMRI-TRUS fusion versus 14-fragments prostatic biopsy. A prospective controlled study

    International Nuclear Information System (INIS)

    Mariotti, Guilherme C.; Falsarella, Priscila M.; Garcia, Rodrigo G.; Queiroz, Marcos R.G.; Lemos, Gustavo C.; Baroni, Ronaldo H.

    2018-01-01

    To compare the incremental diagnostic value of targeted biopsy using real-time multiparametric magnetic resonance imaging and transrectal ultrasound (mpMRI-TRUS) fusion to conventional 14-cores biopsy. Uni-institutional, institutional review board (IRB) approved prospective blinded study comparing TRUS-guided random and targeted biopsy using mpMRI-TRUS fusion, in 100 consecutive men. We included men with clinical-laboratorial suspicious for prostate cancer and Likert score ≥ 3 mp-MRI. Patients previously diagnosed with prostate cancer were excluded. All patients were submitted to 14-cores TRUS-guided biopsy (mpMRI data operator-blinded), followed by targeted biopsy using mpMRI-TRUS fusion. There was an overall increase in cancer detection rate, from 56% with random technique to 62% combining targeted biopsy using mpMRI-TRUS fusion; incremental diagnosis was even more relevant for clinically significant lesions (Gleason ≥ 7), diagnosing 10% more clinically significant lesions with fusion biopsy technique. Diagnosis upgrade occurred in 5 patients that would have negative results in random biopsies and had clinically significant tumours with the combined technique, and in 5 patients who had the diagnosis of significant tumours after fusion biopsy and clinically insignificant tumours in random biopsies(p=0.0010). Targeted biopsy using mpMRI-TRUS fusion has incremental diagnostic value in comparison to conventional random biopsy, better detecting clinically significant prostate cancers. (orig.)

  7. Incremental diagnostic value of targeted biopsy using mpMRI-TRUS fusion versus 14-fragments prostatic biopsy. A prospective controlled study

    Energy Technology Data Exchange (ETDEWEB)

    Mariotti, Guilherme C.; Falsarella, Priscila M.; Garcia, Rodrigo G.; Queiroz, Marcos R.G. [Hospital Israelita Albert Einstein, Department of Interventional Radiology, Sao Paulo (Brazil); Lemos, Gustavo C. [Hospital Israelita Albert Einstein, Department of Urology, Sao Paulo (Brazil); Baroni, Ronaldo H. [Hospital Israelita Albert Einstein, Department of Radiology, Sao Paulo (Brazil)

    2018-01-15

    To compare the incremental diagnostic value of targeted biopsy using real-time multiparametric magnetic resonance imaging and transrectal ultrasound (mpMRI-TRUS) fusion to conventional 14-cores biopsy. Uni-institutional, institutional review board (IRB) approved prospective blinded study comparing TRUS-guided random and targeted biopsy using mpMRI-TRUS fusion, in 100 consecutive men. We included men with clinical-laboratorial suspicious for prostate cancer and Likert score ≥ 3 mp-MRI. Patients previously diagnosed with prostate cancer were excluded. All patients were submitted to 14-cores TRUS-guided biopsy (mpMRI data operator-blinded), followed by targeted biopsy using mpMRI-TRUS fusion. There was an overall increase in cancer detection rate, from 56% with random technique to 62% combining targeted biopsy using mpMRI-TRUS fusion; incremental diagnosis was even more relevant for clinically significant lesions (Gleason ≥ 7), diagnosing 10% more clinically significant lesions with fusion biopsy technique. Diagnosis upgrade occurred in 5 patients that would have negative results in random biopsies and had clinically significant tumours with the combined technique, and in 5 patients who had the diagnosis of significant tumours after fusion biopsy and clinically insignificant tumours in random biopsies(p=0.0010). Targeted biopsy using mpMRI-TRUS fusion has incremental diagnostic value in comparison to conventional random biopsy, better detecting clinically significant prostate cancers. (orig.)

  8. A 3 T event-related functional magnetic resonance imaging (fMRI) study of primary and secondary gustatory cortex localization using natural tastants

    International Nuclear Information System (INIS)

    Smits, Marion; Peeters, Ronald R.; Hecke, Paul van; Sunaert, Stefan

    2007-01-01

    It is known that taste is centrally represented in the insula, frontal and parietal operculum, as well as in the orbitofrontal cortex (secondary gustatory cortex). In functional MRI (fMRI) experiments activation in the insula has been confirmed, but activation in the orbitofrontal cortex is only infrequently found, especially at higher field strengths (3 T). Due to large susceptibility artefacts, the orbitofrontal cortex is a difficult region to examine with fMRI. Our aim was to localize taste in the human cortex at 3 T, specifically in the orbitofrontal cortex as well as in the primary gustatory cortex. Event-related fMRI was performed at 3 T in seven healthy volunteers. Taste stimuli consisted of lemon juice and chocolate. To visualize activation in the orbitofrontal cortex a dedicated 3D SENSE EPI fMRI sequence was used, in addition to a 2D SENSE EPI fMRI sequence for imaging the entire brain. Data were analyzed using a perception-based model. The dedicated 3D SENSE EPI sequence successfully reduced susceptibility artefacts in the orbitofrontal area. Significant taste-related activation was found in the orbitofrontal and insular cortices. fMRI of the orbitofrontal cortex is feasible at 3 T, using a dedicated sequence. Our results corroborate findings from previous studies. (orig.)

  9. A 3 T event-related functional magnetic resonance imaging (fMRI) study of primary and secondary gustatory cortex localization using natural tastants

    Energy Technology Data Exchange (ETDEWEB)

    Smits, Marion [Erasmus MC, University Medical Center Rotterdam, Department of Radiology, P.O. Box 2040, CA Rotterdam (Netherlands); K.U.Leuven, Department of Radiology, University Hospitals, Leuven (Belgium); Peeters, Ronald R.; Hecke, Paul van; Sunaert, Stefan [K.U.Leuven, Department of Radiology, University Hospitals, Leuven (Belgium)

    2007-01-15

    It is known that taste is centrally represented in the insula, frontal and parietal operculum, as well as in the orbitofrontal cortex (secondary gustatory cortex). In functional MRI (fMRI) experiments activation in the insula has been confirmed, but activation in the orbitofrontal cortex is only infrequently found, especially at higher field strengths (3 T). Due to large susceptibility artefacts, the orbitofrontal cortex is a difficult region to examine with fMRI. Our aim was to localize taste in the human cortex at 3 T, specifically in the orbitofrontal cortex as well as in the primary gustatory cortex. Event-related fMRI was performed at 3 T in seven healthy volunteers. Taste stimuli consisted of lemon juice and chocolate. To visualize activation in the orbitofrontal cortex a dedicated 3D SENSE EPI fMRI sequence was used, in addition to a 2D SENSE EPI fMRI sequence for imaging the entire brain. Data were analyzed using a perception-based model. The dedicated 3D SENSE EPI sequence successfully reduced susceptibility artefacts in the orbitofrontal area. Significant taste-related activation was found in the orbitofrontal and insular cortices. fMRI of the orbitofrontal cortex is feasible at 3 T, using a dedicated sequence. Our results corroborate findings from previous studies. (orig.)

  10. Thoughts turned into high-level commands: Proof-of-concept study of a vision-guided robot arm driven by functional MRI (fMRI) signals.

    Science.gov (United States)

    Minati, Ludovico; Nigri, Anna; Rosazza, Cristina; Bruzzone, Maria Grazia

    2012-06-01

    Previous studies have demonstrated the possibility of using functional MRI to control a robot arm through a brain-machine interface by directly coupling haemodynamic activity in the sensory-motor cortex to the position of two axes. Here, we extend this work by implementing interaction at a more abstract level, whereby imagined actions deliver structured commands to a robot arm guided by a machine vision system. Rather than extracting signals from a small number of pre-selected regions, the proposed system adaptively determines at individual level how to map representative brain areas to the input nodes of a classifier network. In this initial study, a median action recognition accuracy of 90% was attained on five volunteers performing a game consisting of collecting randomly positioned coloured pawns and placing them into cups. The "pawn" and "cup" instructions were imparted through four mental imaginery tasks, linked to robot arm actions by a state machine. With the current implementation in MatLab language the median action recognition time was 24.3s and the robot execution time was 17.7s. We demonstrate the notion of combining haemodynamic brain-machine interfacing with computer vision to implement interaction at the level of high-level commands rather than individual movements, which may find application in future fMRI approaches relevant to brain-lesioned patients, and provide source code supporting further work on larger command sets and real-time processing. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

  11. [Use of MRI before biopsy in diagnosis of prostate cancer: Single-operator study].

    Science.gov (United States)

    Bassard, S; Mege, J-L

    2015-12-01

    The diagnostic for prostate cancer is changing. To improve the detection of this cancer, urologists expect a lot from the contribution of magnetic resonance imaging (MRI). What is the role of this imaging in prostate cancer detection? This is a retrospective study, from 2011 to 2013, mono-centric and single-operator. Of the 464 needle biopsy of the prostate (BP), we excluded those with PSA>20 ng/mL or digital rectal examination (DRE)>T3. The remaining 430 BP were submitted or not to a 1.5 tesla MRI with pelvic antenna. The primary aim is the overall detection of prostate cancer. Secondary aim was the detection rate during the first series of BP and repeat BP, between the two groups in the MRI group. MRI and MRI without populations are comparable for age (63.3 vs 64.6), PSA (6.10 vs 6.13), DRE>T1c, prostate volume (55.4 cm(3) vs 51.7 cm(3)). There is no significant difference in overall detection between the two groups (P=0.12). There is no significant difference in cancer detection between the first BP (P=0.13) and the repeat BP (P=0.07). There is a significant difference in the early detection of BP MRI group (P=0.03) but not for the BP repeat MRI group (P=0.07). For 108 BP iterative MRI group, there were 67 BP targeted "mentally" with MRI: 18 cancers were detected, making a 25% detection rate. This study helps to highlight the value of MRI in the early rounds of BP but we can ask the value of this imaging during repeat biopsies. Targeted biopsies "mentally" do not have the expected detection sensitivity and seems to require a three-dimensional reconstruction to be more effective. 5. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  12. Radon diffusion coefficients for soils. Previous studies and their application to uranium-bearing wastes

    International Nuclear Information System (INIS)

    Sasaki, Tomozo; Gunji, Yasuyoshi; Iida, Takao

    2008-01-01

    Radon diffusion in soils has been studied over the years by many researchers. The application of such studies to the evaluation of radiation exposure caused by radon from uranium-bearing wastes disposed in a shallow land site is very important. The present paper surveyed closely relevant studies and elucidated the inherent nature of radon diffusion in terms of the definition of radon diffusion coefficients. Then, basic features of measurement methods for determining radon diffusion coefficients in soils were explained. Furthermore, theoretical aspects of radon diffusion in soils were discussed in terms of microscopic radon diffusion in soils and large-scale radon diffusion through cover soil defects for uranium mill tailings. Finally, in order to apply the radon diffusion studies to uranium-bearing waste disposal in shallow land sites, new challenges were presented: elucidation of radon diffusion in uranium-bearing wastes and cover-soil cracks, and demonstration of the validity of applying only radon diffusion in the evaluation of radiation exposure caused by radon, which would come through Japanese cover soils for uranium-bearing waste disposal. (author)

  13. Imaging large vessel vasculitis with fully integrated PET/MRI: a pilot study

    International Nuclear Information System (INIS)

    Einspieler, Ingo; Pyka, Thomas; Eiber, Matthias; Thuermel, Klaus; Wolfram, Sabine; Moog, Philipp; Reeps, Christian; Essler, Markus

    2015-01-01

    The aim of this study was to evaluate the feasibility of hybrid [ 18 F]fluorodeoxyglucose (FDG) positron emission tomography (PET)/MRI in patients with large vessel vasculitis (LVV) by comparing visual and quantitative parameters to that of PET/CT. Furthermore, the value of PET/MRI in disease activity and extent of LVV was assessed. A total of 16 [ 18 F]FDG PET/MRI and 12 [ 18 F]-FDG PET/CT examinations were performed in 12 patients with LVV. MRI of the vessel wall by T1-weighted and T2-weighted sequences was used for anatomical localization of FDG uptake and identification of morphological changes associated with LVV. In addition, contrast-enhanced (CE) magnetic resonance angiography (MRA) was performed. The vascular FDG uptake in the vasculitis group was compared to a reference group of 16 patients using a four-point visual score. Visual scores and quantitative parameters [maximum standardized uptake value (SUV max ) and target to background ratio (TBR)] were compared between PET/MRI and PET/CT. Furthermore, correlations between C-reactive protein (CRP) and quantitative PET results, as well the extent of vasculitis in PET, MRI/CE-MRA and combined PET/MRI, were analysed. TBRs, SUV max values and visual scores correlated well between PET/MRI and PET/CT (r = 0.92, r = 0.91; r = 0.84, p < 0.05). There was no significant difference between both modalities concerning SUV max measurements and visual scores. In PET/MRI, PET alone revealed abnormal FDG uptake in 86 vascular regions. MRI/CE-MRA indicated 49 vessel segments with morphological changes related to vasculitis, leading to a total number of 95 vasculitis regions in combination with PET. Strong and significant correlations between CRP and disease extent in PET alone (r = 0.75, p = 0.0067) and PET/MRI (r = 0.92, p < 0.0001) in contrast to MRI/CE-MRA only were observed. Regarding disease activity, no significant correlations were seen between quantitative PET results and CRP, although there was a trend towards

  14. Imaging large vessel vasculitis with fully integrated PET/MRI: a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Einspieler, Ingo; Pyka, Thomas; Eiber, Matthias [Technische Universitaet Muenchen, Klinikum rechts der Isar, Department of Nuclear Medicine, Munich (Germany); Thuermel, Klaus; Wolfram, Sabine; Moog, Philipp [Technische Universitaet Muenchen, Klinikum rechts der Isar, Department of Nephrology, Munich (Germany); Reeps, Christian [Technische Universitaet Muenchen, Department of Vascular Surgery, Klinikum rechts der Isar, Munich (Germany); Essler, Markus [Rheinische Friedrich-Wilhelms-Universitaet, Department of Nuclear Medicine, Universitaetsklinikum Bonn, Bonn (Germany)

    2015-04-16

    The aim of this study was to evaluate the feasibility of hybrid [{sup 18}F]fluorodeoxyglucose (FDG) positron emission tomography (PET)/MRI in patients with large vessel vasculitis (LVV) by comparing visual and quantitative parameters to that of PET/CT. Furthermore, the value of PET/MRI in disease activity and extent of LVV was assessed. A total of 16 [{sup 18}F]FDG PET/MRI and 12 [{sup 18}F]-FDG PET/CT examinations were performed in 12 patients with LVV. MRI of the vessel wall by T1-weighted and T2-weighted sequences was used for anatomical localization of FDG uptake and identification of morphological changes associated with LVV. In addition, contrast-enhanced (CE) magnetic resonance angiography (MRA) was performed. The vascular FDG uptake in the vasculitis group was compared to a reference group of 16 patients using a four-point visual score. Visual scores and quantitative parameters [maximum standardized uptake value (SUV{sub max}) and target to background ratio (TBR)] were compared between PET/MRI and PET/CT. Furthermore, correlations between C-reactive protein (CRP) and quantitative PET results, as well the extent of vasculitis in PET, MRI/CE-MRA and combined PET/MRI, were analysed. TBRs, SUV{sub max} values and visual scores correlated well between PET/MRI and PET/CT (r = 0.92, r = 0.91; r = 0.84, p < 0.05). There was no significant difference between both modalities concerning SUV{sub max} measurements and visual scores. In PET/MRI, PET alone revealed abnormal FDG uptake in 86 vascular regions. MRI/CE-MRA indicated 49 vessel segments with morphological changes related to vasculitis, leading to a total number of 95 vasculitis regions in combination with PET. Strong and significant correlations between CRP and disease extent in PET alone (r = 0.75, p = 0.0067) and PET/MRI (r = 0.92, p < 0.0001) in contrast to MRI/CE-MRA only were observed. Regarding disease activity, no significant correlations were seen between quantitative PET results and CRP, although there

  15. Interbirth interval and history of previous preeclampsia: a case–control study among multiparous women

    OpenAIRE

    Harutyunyan, Arusyak; Armenian, Haroutune; Petrosyan, Varduhi

    2013-01-01

    Abstract Background Preeclampsia is a disorder with a reported incidence of 2%-8% among all pregnancies, accounting for more than 50,000 deaths worldwide each year. In low- and middle- income countries maternal/perinatal morbidity and mortality associated with preeclampsia are high due to the lack of proper prenatal and hospital care and limited access to neonatal intensive care. The objectives of our study were to determine the association of long in...

  16. A Review of Previous Studies on Information Processing in Career Decision Making among University Students

    OpenAIRE

    池田, 智子; Satoko, Ikeda

    2018-01-01

    This review of the researches of career choice of Japanese university students focused the studies on decision-making theory conducted in Japan. The present review suggested the necessity of examination of the effect of self-efficacy about career information search on the process of career choice. It is also needed to examine the relationship between specific self-efficacy about career information search and career decision-making self-efficacy, moreover, general self-efficacy.

  17. A Comment Upon Previous Studies on 3-D Boundary Layer Transition

    OpenAIRE

    ÇARPINLIOĞLU, Melda Özdinç

    2014-01-01

    The common feature of the experimental studies upon 3-D boundary layer development on swept flat plates cited in the available literature is the application of streamwise and/or spanwise pressure gradients. In fact; presence of the pressure gradients was suggested to be vital for having crossflow effective in 3-D boundary layer transition. In the presented paper here, this idea is questioned evaluating the results of an experimental investigation conducted on swept flat plates under the ab...

  18. Neuropsychiatric and cardiometabolic comorbidities in patients with previously diagnosed Cushing's disease: a longitudinal observational study

    OpenAIRE

    Dimopoulou, C; Geraedts, V; Stalla, G K; Sievers, C

    2015-01-01

    INTRODUCTION: Only few studies have systematically investigated neuropsychiatric aspects in patients with Cushing's disease (CD). Pain syndromes have been described in patients with pituitary adenomas, but so far no systematical investigation has been conducted in patients with CD. Additionally, CD has an association with cardiometabolic comorbidities which ultimately leads to increased morbidity and mortality. Long-term treatment of the hypercortisolic state cannot prevent the persistence of...

  19. A New Zealand based cohort study of anaesthetic trainees' career outcomes compared with previously expressed intentions.

    Science.gov (United States)

    Moran, E M L; French, R A; Kennedy, R R

    2011-09-01

    Predicting workforce requirements is a difficult but necessary part of health resource planning. A 'snapshot' workforce survey undertaken in 2002 examined issues that New Zealand anaesthesia trainees expected would influence their choice of future workplace. We have restudied the same cohort to see if that workforce survey was a good predictor of outcome. Seventy (51%) of 138 surveys were completed in 2009 compared with 100 (80%) of 138 in the 2002 survey. Eighty percent of the 2002 respondents planned consultant positions in New Zealand. We found 64% of respondents were working in New Zealand (P New Zealand based respondents but only 40% of those living outside New Zealand agreed or strongly agreed with this statement (P New Zealand but was important for only 2% of those resident in New Zealand (P New Zealand were predominantly between NZ$150,000 and $200,000 while those overseas received between NZ$300,000 and $400,000. Of those that are resident in New Zealand, 84% had studied in a New Zealand medical school compared with 52% of those currently working overseas (P < 0.01). Our study shows that stated career intentions in a group do not predict the actual group outcomes. We suggest that 'snapshot' studies examining workforce intentions are of little value for workforce planning. However we believe an ongoing program matching career aspirations against career outcomes would be a useful tool in workforce planning.

  20. Functional MRI study of cerebral cortical activation during volitional swallowing

    International Nuclear Information System (INIS)

    Wakasa, Toru; Aiga, Hideki; Yanagi, Yoshinobu; Kawai, Noriko; Sugimoto, Tomosada; Kuboki, Takuo; Kishi, Kanji

    2002-01-01

    The purpose of this study was to investigate the somatotropic distribution and lateralization of motor and sensory cortical activity during swallowing in healthy adult human subjects using functional MR imaging. Nine healthy right-handed adult volunteers (6 men, 3 women; ages 22-38) were examined. Their cortical activities were evoked by having them swallow, five times, a small bolus of water (3 ml) supplied through a plastic catheter. As a positive control, the subjects performed five repetitions of right-handed grasping tasks. Blood oxygenation level-dependent images were obtained using a 1.5 Tesla MR system (Magnetom Vision, Siemens Germany; repetition time/echo time (TR/TE)=0.96/0.66, flip angle (FA)=90 deg). T1 weighted anatomical images were obtained for the same slices in each subject. Cerebral activity was observed most notably in the primary motor cortex and primary somatosensory cortex, followed by the premotor cortex, anterior cingulate cortex, frontal operculum, and insula. The hand-grasping task activated relatively superior parts of the primary motor and somatosensory cortices. The swallowing task, on the other hand, activated the inferior parts of the pre- and postcentral gyri. The hand-grasping activation of motor and sensory cortices was localized absolutely on the contralateral side, whereas swallowing activated the motor cortex either bilaterally or unilaterally. Swallowing activated the sensory cortex almost always bilaterally. This study suggested that fMRI could be used to identify the specific areas of cortical activation caused by various tasks, and to differentiate the locations of cortical activation between tasks. (author)

  1. Functional MRI study of cerebral cortical activation during volitional swallowing

    Energy Technology Data Exchange (ETDEWEB)

    Wakasa, Toru; Aiga, Hideki; Yanagi, Yoshinobu; Kawai, Noriko; Sugimoto, Tomosada; Kuboki, Takuo; Kishi, Kanji [Okayama Univ. (Japan). Graduate School of Medicine and Dentistry

    2002-12-01

    The purpose of this study was to investigate the somatotropic distribution and lateralization of motor and sensory cortical activity during swallowing in healthy adult human subjects using functional MR imaging. Nine healthy right-handed adult volunteers (6 men, 3 women; ages 22-38) were examined. Their cortical activities were evoked by having them swallow, five times, a small bolus of water (3 ml) supplied through a plastic catheter. As a positive control, the subjects performed five repetitions of right-handed grasping tasks. Blood oxygenation level-dependent images were obtained using a 1.5 Tesla MR system (Magnetom Vision, Siemens Germany; repetition time/echo time (TR/TE)=0.96/0.66, flip angle (FA)=90 deg). T1 weighted anatomical images were obtained for the same slices in each subject. Cerebral activity was observed most notably in the primary motor cortex and primary somatosensory cortex, followed by the premotor cortex, anterior cingulate cortex, frontal operculum, and insula. The hand-grasping task activated relatively superior parts of the primary motor and somatosensory cortices. The swallowing task, on the other hand, activated the inferior parts of the pre- and postcentral gyri. The hand-grasping activation of motor and sensory cortices was localized absolutely on the contralateral side, whereas swallowing activated the motor cortex either bilaterally or unilaterally. Swallowing activated the sensory cortex almost always bilaterally. This study suggested that fMRI could be used to identify the specific areas of cortical activation caused by various tasks, and to differentiate the locations of cortical activation between tasks. (author)

  2. Studies on the reliability of high-field intra-operative MRI in brain glioma resection

    Directory of Open Access Journals (Sweden)

    Zhi-jun SONG

    2011-07-01

    Full Text Available Objective To evaluate the reliability of high-field intra-operative magnetic resonance imaging(iMRI in detecting the residual tumors during glioma resection.Method One hundred and thirty-one cases of brain glioma(69 males and 62 females,aged from 7 to 79 years with mean of 39.6 years hospitalized from Nov.2009 to Aug.2010 were involved in present study.All the patients were evaluated using magnetic resonance imaging(MRI before the operation.The tumors were resected under conventional navigation microscope,and the high-field iMRI was used for all the patients when the operators considered the tumor was satisfactorily resected,while the residual tumor was difficult to detect under the microscope,but resected after being revealed by high-field iMRI.Histopathological examination was performed.The patients without residual tumors recieved high-field MRI scan at day 4 or 5 after operation to evaluate the accuracy of high-field iMRI during operation.Results High quality intra-operative images were obtained by using high-field iMRI.Twenty-eight cases were excluded because their residual tumors were not resected due to their location too close to functional area.Combined with the results of intra-operative histopathological examination and post-operative MRI at the early recovery stage,the sensitivity of high-field iMRI in residual tumor diagnosis was 98.0%(49/50,the specificity was 94.3%(50/53,and the accuracy was 96.1%(99/103.Conclusion High-quality intra-operative imaging could be acquired by high-field iMRI,which maybe used as a safe and reliable method in detecting the residual tumors during glioma resection.

  3. Usefulness of MRI and SPECT studies in evaluating the lesion of aphasia

    Energy Technology Data Exchange (ETDEWEB)

    Hanyu, Haruo; Kobayashi, Yasutaka; Arai, Hisayuki; Hatano, Nobuyoshi; Yamaguchi, Katsuhiko; Katsunuma, Hideyo (Tokyo Medical Coll. (Japan))

    1990-06-01

    Since the introduction of CT scanning, correlations between neuropsychological findings and anatomical lesions have been studied. Anatomical studies by CT scans may, however, be misleading in delineating the extent of lesions in aphasia. We have carried out MRI (magnetic resonance imaging) and SPECT (single photon emission CT) examinations in 15 aphasic patients with cerebrovascular disease and discussed the usefulness of these studies. Compared to CT scan, MRI or SPECT studies were considered to be very useful in 8 of 15 patients. The useful points of these studies were: (1) easy detection of lesions with undetectable damages on CT, (2) demonstration of functional abnormalities in areas adjacent or distant from cerebrovascular lesions, and (3) precise definition of topographical abnormalities because of the three-dimensional imaging capability of MRI. As MRI or SPECT may define the actual extent of lesions and show areas of functional abnormality, these studies are useful and necessary in the assessment of lesions causing aphasia. (author).

  4. Usefulness of MRI and SPECT studies in evaluating the lesion of aphasia

    International Nuclear Information System (INIS)

    Hanyu, Haruo; Kobayashi, Yasutaka; Arai, Hisayuki; Hatano, Nobuyoshi; Yamaguchi, Katsuhiko; Katsunuma, Hideyo

    1990-01-01

    Since the introduction of CT scanning, correlations between neuropsychological findings and anatomical lesions have been studied. Anatomical studies by CT scans may, however, be misleading in delineating the extent of lesions in aphasia. We have carried out MRI (magnetic resonance imaging) and SPECT (single photon emission CT) examinations in 15 aphasic patients with cerebrovascular disease and discussed the usefulness of these studies. Compared to CT scan, MRI or SPECT studies were considered to be very useful in 8 of 15 patients. The useful points of these studies were: 1) easy detection of lesions with undetectable damages on CT, 2) demonstration of functional abnormalities in areas adjacent or distant from cerebrovascular lesions, and 3) precise definition of topographical abnormalities because of the three-dimensional imaging capability of MRI. As MRI or SPECT may define the actual extent of lesions and show areas of functional abnormality, these studies are useful and necessary in the assessment of lesions causing aphasia. (author)

  5. Cerebral fat embolism studied with MRI and SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Erdem, E. (Dept. of Neurology, Hacettepe Univ. School of Medicine, Ankara (Turkey)); Namer, I.J. (Inst. of Biophysics, Faculty of Medicine, Louis Pasteur Univ., Strasbourg (France)); Saribas, O. (Dept. of Neurology, Hacettepe Univ. School of Medicine, Ankara (Turkey)); Aras, T. (Dept. of Nuclear Medicine, Hacettepe Univ. School of Medicine Ankara (Turkey)); Tan, E. (Dept. of Neurology, Hacettepe Univ. School of Medicine, Ankara (Turkey)); Bekdik, C. (Dept. of Nuclear Medicine, Hacettepe Univ. School of Medicine Ankara (Turkey)); Zileli, T. (Dept. of Neurology, Hacettepe Univ. School of Medicine, Ankara (Turkey))

    1993-03-01

    In a patient with fat embolism to the brain CT showed no abnormality. MRI performed after recovery from coma, when the patient had aphasia and quadriparesis, demonstrated multiple high signal abnormalities in the white matter on both T1- and T2-weighted images. HMPAO-SPECT showed left-sided hypoperfusion which resolved in parallel with clinical improvement 1 month later. (orig.)

  6. The diagnostic and therapeutic impact of MRI: an observational multi-centre study

    Energy Technology Data Exchange (ETDEWEB)

    Hollingworth, William; Todd, Christopher J.; Bell, Matthew I.; Arafat, Qais; Girling, Simon; Karia, Kanti R.; Dixon, Adrian K

    2000-11-01

    AIM: To provide information about the diagnostic and therapeutic impact of magnetic resonance imaging (MRI) and to compare the findings across diagnostic groups. MATERIALS AND METHODS: A prospective, observational study of 2017 consecutive referrals for MRI of the head, spine or knee at four imaging centres. Clinicians completed questionnaires before MRI stating initial diagnoses, diagnostic confidence and treatment plans. After imaging, a second questionnaire evaluated clinicians' revised diagnosis and treatment plans in the light of imaging findings. Patients were grouped into nine diagnostic categories for analysis. Comparison between pre- and post-imaging was used to assess the diagnostic and therapeutic impact of MRI. RESULTS: In seven of nine diagnostic groups MRI findings were associated with a diagnostic impact. Diagnoses were revised or discarded following normal MR findings and diagnostic confidence was increased by confirmative MR findings. There was no statistically significant diagnostic impact for suspected pituitary or cerebello-pontine angle lesions. In five of nine diagnostic groups (knee meniscus, knee ligament, multiple sclerosis, lumbar and cervical spine) MRI findings had a clear impact on treatment plans. CONCLUSION: This study demonstrates that in most diagnostic categories, MRI influences diagnosis and treatment. However, experimental studies are needed to prove that these diagnostic and therapeutic impacts lead to improved health. Hollingworth (2000)

  7. The diagnostic and therapeutic impact of MRI: an observational multi-centre study

    International Nuclear Information System (INIS)

    Hollingworth, William; Todd, Christopher J.; Bell, Matthew I.; Arafat, Qais; Girling, Simon; Karia, Kanti R.; Dixon, Adrian K.

    2000-01-01

    AIM: To provide information about the diagnostic and therapeutic impact of magnetic resonance imaging (MRI) and to compare the findings across diagnostic groups. MATERIALS AND METHODS: A prospective, observational study of 2017 consecutive referrals for MRI of the head, spine or knee at four imaging centres. Clinicians completed questionnaires before MRI stating initial diagnoses, diagnostic confidence and treatment plans. After imaging, a second questionnaire evaluated clinicians' revised diagnosis and treatment plans in the light of imaging findings. Patients were grouped into nine diagnostic categories for analysis. Comparison between pre- and post-imaging was used to assess the diagnostic and therapeutic impact of MRI. RESULTS: In seven of nine diagnostic groups MRI findings were associated with a diagnostic impact. Diagnoses were revised or discarded following normal MR findings and diagnostic confidence was increased by confirmative MR findings. There was no statistically significant diagnostic impact for suspected pituitary or cerebello-pontine angle lesions. In five of nine diagnostic groups (knee meniscus, knee ligament, multiple sclerosis, lumbar and cervical spine) MRI findings had a clear impact on treatment plans. CONCLUSION: This study demonstrates that in most diagnostic categories, MRI influences diagnosis and treatment. However, experimental studies are needed to prove that these diagnostic and therapeutic impacts lead to improved health. Hollingworth (2000)

  8. Comparative study on developmental stages of the clavicle by postmortem MRI and CT imaging

    DEFF Research Database (Denmark)

    Larsen, Sara Tangmose; Lynnerup, Niels; Jensen, K.E.

    2013-01-01

    Objectives: The developmental stages of the clavicles are important for forensic age estimation purposes in adolescents. This study compares the 4-stage system to evaluate the ossification of the medial end of the clavicle as visualized by magnetic resonance imaging (MRI) and computed tomography...... (CT). As several forensic institutes routinely perform CT scans, the large amount of available data may serve as reference sample for MRI in specific cases. Material and methods: This prospective study included an MRI and CT scan of 47 autopsy cases performed prior to medico-legal autopsy (age range...

  9. Life cycle impact assessment of ammonia production in Algeria: A comparison with previous studies

    Energy Technology Data Exchange (ETDEWEB)

    Makhlouf, Ali, E-mail: almakhsme@gmail.com; Serradj, Tayeb; Cheniti, Hamza

    2015-01-15

    In this paper, a Life Cycle Analysis (LCA) from “cradle to gate” of one anhydrous ton of ammonia with a purity of 99% was achieved. Particularly, the energy and environmental performance of the product (ammonia) were evaluated. The eco-profile of the product and the share of each stage of the Life Cycle on the whole environmental impacts have been evaluated. The flows of material and energy for each phase of the life cycle were counted and the associated environmental problems were identified. Evaluation of the impact was achieved using GEMIS 4.7 software. The primary data collection was executed at the production installations located in Algeria (Annaba locality). The analysis was conducted according to the LCA standards ISO 14040 series. The results show that Cumulative Energy Requirement (CER) is of 51.945 × 10{sup 3} MJ/t of ammonia, which is higher than the global average. Global Warming Potential (GWP) is of 1.44 t CO{sub 2} eq/t of ammonia; this value is lower than the world average. Tropospheric ozone precursor and Acidification are also studied in this article, their values are: 549.3 × 10{sup −6} t NMVOC eq and 259.3 × 10{sup −6} t SO{sub 2} eq respectively.

  10. Life cycle impact assessment of ammonia production in Algeria: A comparison with previous studies

    International Nuclear Information System (INIS)

    Makhlouf, Ali; Serradj, Tayeb; Cheniti, Hamza

    2015-01-01

    In this paper, a Life Cycle Analysis (LCA) from “cradle to gate” of one anhydrous ton of ammonia with a purity of 99% was achieved. Particularly, the energy and environmental performance of the product (ammonia) were evaluated. The eco-profile of the product and the share of each stage of the Life Cycle on the whole environmental impacts have been evaluated. The flows of material and energy for each phase of the life cycle were counted and the associated environmental problems were identified. Evaluation of the impact was achieved using GEMIS 4.7 software. The primary data collection was executed at the production installations located in Algeria (Annaba locality). The analysis was conducted according to the LCA standards ISO 14040 series. The results show that Cumulative Energy Requirement (CER) is of 51.945 × 10 3 MJ/t of ammonia, which is higher than the global average. Global Warming Potential (GWP) is of 1.44 t CO 2 eq/t of ammonia; this value is lower than the world average. Tropospheric ozone precursor and Acidification are also studied in this article, their values are: 549.3 × 10 −6 t NMVOC eq and 259.3 × 10 −6 t SO 2 eq respectively

  11. Processes in arithmetic strategy selection: A fMRI study.

    Directory of Open Access Journals (Sweden)

    Julien eTaillan

    2015-02-01

    Full Text Available This neuroimaging (fMRI study investigated neural correlates of strategy selection. Young adults performed an arithmetic task in two different conditions. In both conditions, participants had to provide estimates of two-digit multiplication problems like 54 x 78. In the choice condition, participants had to select the better of two available rounding strategies, rounding-up strategy (RU (i.e., doing 60x80 = 4,800 or rounding-down strategy (RD (i.e., doing 50x70=3,500 to estimate product of 54x78. In the no-choice condition, participants did not have to select strategy on each problem but were told which strategy to use; they executed RU and RD strategies each on a series of problems. Participants also had a control task (i.e., providing correct products of multiplication problems like 40x50. Brain activations and performance were analyzed as a function of these conditions. Participants were able to frequently choose the better strategy in the choice condition; they were also slower when they executed the difficult RU than the easier RD. Neuroimaging data showed greater brain activations in right anterior cingulate cortex (ACC, dorso-lateral prefrontal cortex (DLPFC, and angular gyrus (ANG, when selecting (relative to executing the better strategy on each problem. Moreover, RU was associated with more parietal cortex activation than RD. These results suggest an important role of fronto-parietal network in strategy selection and have important implications for our further understanding and modelling cognitive processes underlying strategy selection.

  12. The role of the DLPFC in inductive reasoning of MCI patients and normal agings: an fMRI study.

    Science.gov (United States)

    Yang, YanHui; Liang, PeiPeng; Lu, ShengFu; Li, KunCheng; Zhong, Ning

    2009-08-01

    Previous studies of young people have revealed that the left dorsolateral prefrontal cortex (DLPFC) plays an important role in inductive reasoning. An fMRI experiment was performed in this study to examine whether the left DLPFC was involved in inductive reasoning of MCI patients and normal aging, and whether the activation pattern of this region was different between MCI patients and normal aging. The fMRI results indicated that MCI patients had no difference from normal aging in behavior performance (reaction time and accuracy) and the activation pattern of DLPFC. However, the BOLD response of the DLPFC region for MCI patients was weaker than that for normal aging, and the functional connectivity between the bilateral DLPFC regions for MCI patients was significantly higher than for normal aging. Taken together, these results indicated that DLPFC plays an important role in inductive reasoning of aging, and the functional abnormity of DLPFC may be an earlier marker of MCI before structural alterations.

  13. Negative predictive value of multiparametric MRI for prostate cancer detection: Outcome of 5-year follow-up in men with negative findings on initial MRI studies

    Energy Technology Data Exchange (ETDEWEB)

    Itatani, R., E-mail: banguliao@gmail.com [Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Kumamoto 860-8556 (Japan); Department of Radiology, Kumamoto Chuo Hospital, 1-5-1, Tainoshima, Kumamoto 862-0965 (Japan); Namimoto, T. [Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Kumamoto 860-8556 (Japan); Atsuji, S.; Katahira, K.; Morishita, S. [Department of Radiology, Kumamoto Chuo Hospital, 1-5-1, Tainoshima, Kumamoto 862-0965 (Japan); Kitani, K.; Hamada, Y. [Department of Urology, Kumamoto Chuo Hospital, 1-5-1, Tainoshima, Kumamoto 862-0965 (Japan); Kitaoka, M. [Department of Pathology, Kumamoto Chuo Hospital, 1-5-1, Tainoshima, Kumamoto 862-0965 (Japan); Nakaura, T. [Department of Diagnostic Radiology, Amakusa Medical Center, Kameba 854-1, Amakusa, Kumamoto 863-0046 (Japan); Yamashita, Y. [Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1, Honjo, Kumamoto 860-8556 (Japan)

    2014-10-15

    Highlights: • We assess the negative predictive value of multiparametric MRI for prostate cancer. • Patients with positive prostate biopsy findings were defined as false-negative. • Patients with negative initial prostate biopsy findings were followed up for 5 years. • The negative predictive value was 89.6% for significant prostate cancer. • MRI is a useful tool to rule out significant prostate cancer before biopsy. - Abstract: Objective: To assess the clinical negative predictive value (NPV) of multiparametric MRI (mp-MRI) for prostate cancer in a 5-year follow-up. Materials and methods: One hundred ninety-three men suspected of harboring prostate cancer with negative MRI findings were included. Patients with positive transrectal ultrasound (TRUS)-guided biopsy findings were defined as false-negative. Patients with negative initial TRUS-guided biopsy findings were followed up and only patients with negative findings by digital rectal examination, MRI, and repeat biopsy and no increase in PSA at 5-year follow-up were defined as “clinically negative”. The clinical NPV of mp-MRI was calculated. For quantitative analysis, mean signal intensity on T2-weighted images and the mean apparent diffusion coefficient value on ADC maps of the initial MRI studies were compared between peripheral-zone (PZ) cancer and the normal PZ based on pathologic maps of patients who had undergone radical prostatectomy. Results: The clinical NPV of mp-MRI was 89.6% for significant prostate cancer. Small cancers, prostatitis, and benign prostatic hypertrophy masking prostate cancer returned false-negative results. Quantitative analysis showed that there was no significant difference between PZ cancer and the normal PZ. Conclusion: The mp-MRI revealed a high clinical NPV and is a useful tool to rule out clinically significant prostate cancer before biopsy.

  14. Negative predictive value of multiparametric MRI for prostate cancer detection: Outcome of 5-year follow-up in men with negative findings on initial MRI studies

    International Nuclear Information System (INIS)

    Itatani, R.; Namimoto, T.; Atsuji, S.; Katahira, K.; Morishita, S.; Kitani, K.; Hamada, Y.; Kitaoka, M.; Nakaura, T.; Yamashita, Y.

    2014-01-01

    Highlights: • We assess the negative predictive value of multiparametric MRI for prostate cancer. • Patients with positive prostate biopsy findings were defined as false-negative. • Patients with negative initial prostate biopsy findings were followed up for 5 years. • The negative predictive value was 89.6% for significant prostate cancer. • MRI is a useful tool to rule out significant prostate cancer before biopsy. - Abstract: Objective: To assess the clinical negative predictive value (NPV) of multiparametric MRI (mp-MRI) for prostate cancer in a 5-year follow-up. Materials and methods: One hundred ninety-three men suspected of harboring prostate cancer with negative MRI findings were included. Patients with positive transrectal ultrasound (TRUS)-guided biopsy findings were defined as false-negative. Patients with negative initial TRUS-guided biopsy findings were followed up and only patients with negative findings by digital rectal examination, MRI, and repeat biopsy and no increase in PSA at 5-year follow-up were defined as “clinically negative”. The clinical NPV of mp-MRI was calculated. For quantitative analysis, mean signal intensity on T2-weighted images and the mean apparent diffusion coefficient value on ADC maps of the initial MRI studies were compared between peripheral-zone (PZ) cancer and the normal PZ based on pathologic maps of patients who had undergone radical prostatectomy. Results: The clinical NPV of mp-MRI was 89.6% for significant prostate cancer. Small cancers, prostatitis, and benign prostatic hypertrophy masking prostate cancer returned false-negative results. Quantitative analysis showed that there was no significant difference between PZ cancer and the normal PZ. Conclusion: The mp-MRI revealed a high clinical NPV and is a useful tool to rule out clinically significant prostate cancer before biopsy

  15. Comparative study of SVM methods combined with voxel selection for object category classification on fMRI data.

    Science.gov (United States)

    Song, Sutao; Zhan, Zhichao; Long, Zhiying; Zhang, Jiacai; Yao, Li

    2011-02-16

    Support vector machine (SVM) has been widely used as accurate and reliable method to decipher brain patterns from functional MRI (fMRI) data. Previous studies have not found a clear benefit for non-linear (polynomial kernel) SVM versus linear one. Here, a more effective non-linear SVM using radial basis function (RBF) kernel is compared with linear SVM. Different from traditional studies which focused either merely on the evaluation of different types of SVM or the voxel selection methods, we aimed to investigate the overall performance of linear and RBF SVM for fMRI classification together with voxel selection schemes on classification accuracy and time-consuming. Six different voxel selection methods were employed to decide which voxels of fMRI data would be included in SVM classifiers with linear and RBF kernels in classifying 4-category objects. Then the overall performances of voxel selection and classification methods were compared. Results showed that: (1) Voxel selection had an important impact on the classification accuracy of the classifiers: in a relative low dimensional feature space, RBF SVM outperformed linear SVM significantly; in a relative high dimensional space, linear SVM performed better than its counterpart; (2) Considering the classification accuracy and time-consuming holistically, linear SVM with relative more voxels as features and RBF SVM with small set of voxels (after PCA) could achieve the better accuracy and cost shorter time. The present work provides the first empirical result of linear and RBF SVM in classification of fMRI data, combined with voxel selection methods. Based on the findings, if only classification accuracy was concerned, RBF SVM with appropriate small voxels and linear SVM with relative more voxels were two suggested solutions; if users concerned more about the computational time, RBF SVM with relative small set of voxels when part of the principal components were kept as features was a better choice.

  16. Surgical considerations when reporting MRI studies of soft tissue sarcoma of the limbs

    Energy Technology Data Exchange (ETDEWEB)

    De la Hoz Polo, Marcela [Kings College Hospital, Radiology Department, London, Brixton (United Kingdom); Dick, Elizabeth [St Mary' s Hospital, Imperial College Healthcare NHS Trust, Radiology Department, London (United Kingdom); Bhumbra, Rej [Newham and The Royal London Hospitals, Trauma and Orthopaedic Department, Barts Health Orthopaedic Centre, London, Whitechapel (United Kingdom); Pollock, Rob [Royal National Orthopaedic Hospital, Trauma and Orthopaedic Department, Stanmore (United Kingdom); Sandhu, Ranbir [University Hospitals Birmingham, Radiology Department, Queen Elizabeth Hospital, Birmingham (United Kingdom); Saifuddin, Asif [Royal National Orthopaedic Hospital, Radiology Department, Stanmore (United Kingdom)

    2017-12-15

    Soft tissue sarcomas (STS) are rare tumours that require prompt diagnosis and treatment at a specialist centre. Magnetic resonance imaging (MRI) has become the modality of choice for identification, characterisation, biopsy planning and staging of soft tissue masses. MRI enables both the operating surgeon and patient to be optimally prepared prior to surgery for the likelihood of margin-negative resection and to anticipate possible sacrifice of adjacent structures and consequent loss of function. The aim of this review is to aid the radiologist in performing and reporting MRI studies of soft tissue sarcomas, with particular reference to the requirements of the surgical oncologist. (orig.)

  17. Integrating fMRI with psychophysiological measurements in the study of decision-making

    OpenAIRE

    Wong, Savio W.H.; Xue, Gui; Bechara, Antoine

    2011-01-01

    Neuroimaging techniques have recently been used to examine the neural mechanism of decision-making. Nevertheless, most of the neuroimaging studies overlook the importance of emotion and autonomic response in modulating the process of decision-making. In this paper, we discussed how to integrating fMRI with psychophysiological measurements in studying decision-making. We suggested that psychophysiological data would complement with fMRI findings in providing a more comprehensive understanding ...

  18. Functional Topography of Human Corpus Callosum: An fMRI Mapping Study

    OpenAIRE

    Fabri, Mara; Polonara, Gabriele

    2013-01-01

    The concept of a topographical map of the corpus callosum (CC) has emerged from human lesion studies and from electrophysiological and anatomical tracing investigations in other mammals. Over the last few years a rising number of researchers have been reporting functional magnetic resonance imaging (fMRI) activation in white matter, particularly the CC. In this study the scope for describing CC topography with fMRI was explored by evoking activation through simple sensory stimulation and moto...

  19. Comparative studies of MRI and operative findings in rotator cuff tear

    International Nuclear Information System (INIS)

    Yamakawa, Seigo; Ichikawa, Norikazu; Itadera, Eichi; Hashizume, Hiroyuki; Inoue, Hajime

    2001-01-01

    A prospective study was performed to determine the accuracy of magnetic resonance imaging (MRI) compared with operative findings in the evaluation of patients associated with rotator cuff tears. Fifty-four of 60 shoulders (58 patients) examined by MRI were confirmed as full-thickness tears and 6 as partial-thickness tears at the time of surgery. The oblique coronal, oblique sagittal, and axial planes of T2-weighted images with the 0.5 tesla MRI system were obtained preoperatively and compared with operative findings. MRI correctly identified 46 of 54 full-thickness rotator cuff tears and 5 of 6 partial-thickness tears. A comparison of MRI and operative findings in full-thickness cuff tears showed a sensitivity of 85%, a specificity of 83%, and a positive prospective value (PPV) of 99%. A comparison of partial-thickness tears showed a sensitivity of 83%, a specificity of 85%, and PPV of 39%. Linear regression analysis showed an excellent correlation between the MRI assessment and measurement at the time of surgery (r=0.90, P<0.01). MRI was useful in evaluating large and medium-sized rotator cuff tears, but less useful in distinguishing small full-thickness tears from partial-thickness tears. (author)

  20. The comparative study of CT and MRI on femoral head necrosis

    International Nuclear Information System (INIS)

    Lin Yunliang; Liu Xianghua; Wu Shiqiang; Zeng Kangnian

    2008-01-01

    Objective: To compare the imaging features of CT and MRI in the femoral head necrosis as well as their pathological basis. Methods: 18 cases (30 hips) with femoral head necrosis proved by follow-up studies or pathology were analyzed, including 3 cases of pathological data. Results: The blurred high-density sclerotic line on CT in 28 hips were corresponded to 'line-like signs' on MRI, whereas, the other two hips without blurred high-density sclerosis line appeared 'line-like signs' on MRI. The normal area surrounded by the high-density line on CT in 26 hips were corresponded to fat-like signal area in 12 hips and mixed signal area in 14 hips on MRI. The other 4 hips with blurred bony trabeculum surrounded by the high-density line on CT showed mixed signal intensity on MRI. Conclusion: The high-density sclerotic line on CT corresponds to 'line-like sign' on MRI, which was considered as reactive interface between necrotic and viable region, was a specific signs to diagnose FHN. Compared with CT, MRI can accurately reflect pathological process during different repaired stages. (authors)

  1. Rhabdomyolysis and truncular sciatic pain. MRI study of 2 cases

    International Nuclear Information System (INIS)

    Le Friant, G.; Brinquin, L.; Soulie, D.; Sarrazin, J.L.; Cosnard, G.; Cordoliani, Y.S.

    1995-01-01

    We report two cases of acute rhabdomyolysis in pelvic girdle muscles with sciatic palsy secondary to compression of the sciatic nerve trunk, with clinical and MRI correlation. The diagnosis of rhabdomyolysis is based on clinical and biological data, but diagnosis of compression complications secondary to swelling of the muscles, especially the compression of nerve trunk, is done by imaging. T2 weighted images give a definite anatomical evaluation. They show enlarged high signal intensity muscles and anatomic relationship with the sciatic nerve from its emergence out of pelvis, giving a good correlation between rhabdomyolysis and the compressed nervous trunk. It helps for planning a possible surgical fasciotomy. However, MRI provides only morphological informations, but not differentiates edema from necrosis in involved muscles. (authors). 7 refs., 2 figs

  2. Hemisphere- and gender-related differences in small-world brain networks: a resting-state functional MRI study.

    Science.gov (United States)

    Tian, Lixia; Wang, Jinhui; Yan, Chaogan; He, Yong

    2011-01-01

    We employed resting-state functional MRI (R-fMRI) to investigate hemisphere- and gender-related differences in the topological organization of human brain functional networks. Brain networks were first constructed by measuring inter-regional temporal correlations of R-fMRI data within each hemisphere in 86 young, healthy, right-handed adults (38 males and 48 females) followed by a graph-theory analysis. The hemispheric networks exhibit small-world attributes (high clustering and short paths) that are compatible with previous results in the whole-brain functional networks. Furthermore, we found that compared with females, males have a higher normalized clustering coefficient in the right hemispheric network but a lower clustering coefficient in the left hemispheric network, suggesting a gender-hemisphere interaction. Moreover, we observed significant hemisphere-related differences in the regional nodal characteristics in various brain regions, such as the frontal and occipital regions (leftward asymmetry) and the temporal regions (rightward asymmetry), findings that are consistent with previous studies of brain structural and functional asymmetries. Together, our results suggest that the topological organization of human brain functional networks is associated with gender and hemispheres, and they provide insights into the understanding of functional substrates underlying individual differences in behaviors and cognition. Copyright © 2010 Elsevier Inc. All rights reserved.

  3. Navicular bone position determined by positional MRI: a reproducibility study

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Philip; Nybing, Janus D. [Copenhagen University Hospital Frederiksberg and Bispebjerg, Department of Radiology, Frederiksberg (Denmark); Johannsen, Finn E.; Stallknecht, Sandra E. [Copenhagen University Hospital Bispebjerg, Institute of Sports Medicine Copenhagen, Copenhagen, NV (Denmark); Hangaard, Stine; Hansen, Bjarke B. [Copenhagen University Hospital Frederiksberg, Parker Institute, Department of Rheumatology, Frederiksberg (Denmark); Boesen, Mikael [Copenhagen University Hospital Frederiksberg and Bispebjerg, Department of Radiology, Frederiksberg (Denmark); Copenhagen University Hospital Frederiksberg, Parker Institute, Department of Rheumatology, Frederiksberg (Denmark)

    2016-02-15

    To examine intraobserver, interobserver and between-day reproducibility of positional MRI for evaluation of navicular bone height (NVH) and medial navicular position (MNP). Positional MRI (pMRI) of the foot was performed on ten healthy participants (0.25 T G-scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). Intraobserver and interobserver reliability was ''substantial'' in both supine and standing position (ICC 0.86-0.98) and showed good agreement (LOA% 4.9-14.7 %). Between-day reliability of navicular height and medial navicular position in standing position remained substantial (ICC 0.85-0.92) with adequate agreement (LOA% 8.3-19.8 %). In supine position between-day reliability was ''moderate'' for NVH (ICC 0.72) and ''slight'' for MNP (ICC 0.39). Agreement remained adequate between-days for MNP in supine position (LOA% 17.7 %), but it was less than adequate for NVH in supine position (LOA% 24.2 %). Navicular height and medial navicular position can be measured by pMRI in a very reproducible manner within and between observers. Increased measurement variation is observed between-days in supine position, which may be due to small positional differences or other unknown biomechanical factors. (orig.)

  4. Navicular bone position determined by positional MRI: a reproducibility study

    International Nuclear Information System (INIS)

    Hansen, Philip; Nybing, Janus D.; Johannsen, Finn E.; Stallknecht, Sandra E.; Hangaard, Stine; Hansen, Bjarke B.; Boesen, Mikael

    2016-01-01

    To examine intraobserver, interobserver and between-day reproducibility of positional MRI for evaluation of navicular bone height (NVH) and medial navicular position (MNP). Positional MRI (pMRI) of the foot was performed on ten healthy participants (0.25 T G-scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). Intraobserver and interobserver reliability was ''substantial'' in both supine and standing position (ICC 0.86-0.98) and showed good agreement (LOA% 4.9-14.7 %). Between-day reliability of navicular height and medial navicular position in standing position remained substantial (ICC 0.85-0.92) with adequate agreement (LOA% 8.3-19.8 %). In supine position between-day reliability was ''moderate'' for NVH (ICC 0.72) and ''slight'' for MNP (ICC 0.39). Agreement remained adequate between-days for MNP in supine position (LOA% 17.7 %), but it was less than adequate for NVH in supine position (LOA% 24.2 %). Navicular height and medial navicular position can be measured by pMRI in a very reproducible manner within and between observers. Increased measurement variation is observed between-days in supine position, which may be due to small positional differences or other unknown biomechanical factors. (orig.)

  5. Preliminary MRI study in patients with congenital complex strabismus

    International Nuclear Information System (INIS)

    Man Fengyuan; Wang Zhenchang; Zhao Bo; Zhu Lei; Xian Junfang; Wang Shijun; Jiao Yonghong; Wu Xiao; Zhao Kanxing

    2009-01-01

    Objective: Although the ocular motility examination has been traditionally used in the diagnosis of complex strabismus resulting from cranial nerve (CN) and extraocular muscles (EOM) abnormalities, magnetic resonance imaging (MRI) now permits the direct imaging of lesions in CNs and EOMs. Methods: Twenty-six patients with complex strabismus underwent MRI examination on 1.5 T MR unit (Twinspeed, GE). Nerves to EOMs were imaged with T 1 weighted in orbits in all patients using phase array surface coils. Results: Patients with Duane syndrome (15 cases, 19 eyes) all exhibited absence or hypoplasia of abducens nerve (CN6), always with mild hypoplasia and apparent misdirection of oculomotor nerve (CN3) to the lateral rectus muscle in the orbit, and there were no hypoplasia of EOMs. Patients with congenital fibrosis of EOMs (9 cases, 16 eyes) exhibited severe hypoplasia of CN3 and CN6, and EOMs appeared hypoptasia to a different degree, particularly severe for the superior rectus and levated palpted muscles. Multiple nerves displayed aplasia in patients with Mobius syndrome (1 ease, 2 eyes) and there was abnormal branch from CN3 to lateral rectus. The tendons of bilateral superior oblique muscles were thin in the patients with Brown syndrome (1 case, 2 eyes). Conclusion: MRI can directly demonstrate absence or hypoplasia of CNs and corresponding EOM abnormalities in congenital complex strabismus, which suggests that the mechanism of congenital complex strabismus is perhaps abnormal innervation or displasia of the ocular motor nerves. (authors)

  6. Functional MRI studies in children with attention deficit hyperactivity disorder

    International Nuclear Information System (INIS)

    Zhang Lei; Jin Zhen; Zeng Yawei; Wang Yan; Zang Yufeng

    2004-01-01

    Objective: To investigate the brain activation map during Go-NoGo tasks in children with attention deficit hyperactivity disorder (ADHD) and matched controls using functional MRI. Methods: Block designed BOLD functional MRI scan covering the whole brain was performed on 10 boys having ADHD and 11 healthy boys. The 2 groups were matched by age, sex, and handedness. Executing advanced inhibitory Go-NoGo tasks served as stimuli for all subjects. The fMRI data was analyzed by SPM99 (Statistical Parametric Mapping) software with statistic t-test to generate the activation map. Results: (1) The normal children showed significant activations in left thalamus and right cingulate gyrus and fewer activations in right middle frontal gyrus during stimulate controlled Go task, but the children with ADHD showed less activations in left thalamus. (2) In response controlled Go task, the normal children showed activations in right insula, cingulate gyrus and left frontal gyrus, while the ADHD children showed lower power of response in the right middle frontal gyrus.(3) In NoGo task, right middle frontal gyrus was the dominant activated regions, and left anterior cingulate, left middle frontal gyrus and right thalamus also had some activations in normal children, while the activations of right prefrontal decreased and the thalamus increased in ADHD boys. Conclusion: In children with ADHD, some dysfunctional brain areas, mainly the prefrontal lobe and anterior cingulate gyrus were found. Thalamus was also involved according to the brain activation map

  7. Functional MRI studies in children with attention deficit hyperactivity disorder

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Zhang; Zhen, Jin; Yawei, Zeng; Yan, Wang [fMRI Center, Lab of Cognition Science and Learning, National Education Ministry and Department of Radiology, 306 Hospital of PLA, Beijing (China); Yufeng, Zang

    2004-06-01

    Objective: To investigate the brain activation map during Go-NoGo tasks in children with attention deficit hyperactivity disorder (ADHD) and matched controls using functional MRI. Methods: Block designed BOLD functional MRI scan covering the whole brain was performed on 10 boys having ADHD and 11 healthy boys. The 2 groups were matched by age, sex, and handedness. Executing advanced inhibitory Go-NoGo tasks served as stimuli for all subjects. The fMRI data was analyzed by SPM99 (Statistical Parametric Mapping) software with statistic t-test to generate the activation map. Results: (1) The normal children showed significant activations in left thalamus and right cingulate gyrus and fewer activations in right middle frontal gyrus during stimulate controlled Go task, but the children with ADHD showed less activations in left thalamus. (2) In response controlled Go task, the normal children showed activations in right insula, cingulate gyrus and left frontal gyrus, while the ADHD children showed lower power of response in the right middle frontal gyrus.(3) In NoGo task, right middle frontal gyrus was the dominant activated regions, and left anterior cingulate, left middle frontal gyrus and right thalamus also had some activations in normal children, while the activations of right prefrontal decreased and the thalamus increased in ADHD boys. Conclusion: In children with ADHD, some dysfunctional brain areas, mainly the prefrontal lobe and anterior cingulate gyrus were found. Thalamus was also involved according to the brain activation map.

  8. Knee joint anterior malalignment and patellofemoral osteoarthritis: an MRI study

    International Nuclear Information System (INIS)

    Tsavalas, Nikolaos; Karantanas, Apostolos H.; Katonis, Pavlos

    2012-01-01

    To evaluate patellofemoral congruency measurements on MRI and correlate the findings with severity of ipsilateral osteoarthritis. We retrospectively reviewed 650 consecutive knee MRI examinations from 622 patients divided into two age groups: ≤50 and >50 year-old. The femoral sulcus angle (SA) and depth (SD), lateral patellar displacement (LPD), lateral patellofemoral angle (LPFA), tibial tubercle-trochlear groove (TT-TG) distance and Insall-Salvati index as well as the grade of focal cartilage defects (ranging from I to IV) in the patellofemoral region were assessed in each subject on axial and sagittal fat-saturated intermediate-w MR images. A significant difference exists between normal and knees with patellofemoral joint osteoarthritis regarding SA (p = 0.0002 and 50 respectively). Significant correlation was found between grading of cartilage defects and SA (rho = 0.21, p = 0.0001 and 0.443, <0.0001), SD (rho = -0.198, p = 0.0003 and -0.418, <0.0001), LPD (rho = 0.176, p = 0.0013 and 0.251, 0.0002) and LPFA (rho = -0.204, p = 0.0002 and -0.239, 0.0005) in both age groups. Knee joint anterior malalignment is multivariably associated with patellofemoral osteoarthritis. circle MRI is an excellent method to evaluate knee alignment and articular cartilage damage. (orig.)

  9. A study of brain MRI findings in children with epilepsy

    International Nuclear Information System (INIS)

    Kanematsu, Sachiko; Sumida, Sawako; Muto, Ayako; Osawa, Makiko; Ono, Yuko; Uchida, Moriyasu; Maruyama, Hiroshi

    2000-01-01

    Magnetic resonance imaging in the brain was performed in 293 patients with childhood-onset (<15 y.o.) epilepsy who had been classified into 4 groups, idiopathic localization-related epilepsy (ILRE), 78 patients; idiopathic generalized epilepsy (IGE), 116 patients; symptomatic localization-related epilepsy (SLRE), 68 patients and symptomatic generalized epilepsy (SGE), 31 patients, with the Classification of Epilepsies and Epileptic Syndrome (1989 International League Against Epilepsy). The examination was performed with a 1.5 T magnet. One hundred twenty-five patients (42.7%) showed abnormal findings, and the incidence in each group was as follows: Idiopathic epilepsy: The rate of abnormal findings in the ILRE and IGE groups was 21.8% and 20.7%, respectively. Most of the abnormal findings were secondary changes, such as diffuse or localized brain atrophy. Of the congenital abnormalities, the main finding was arachnoid cyst. Symptomatic epilepsy: The rate of abnormality in the SLRE patients was 88.2%, and 85% of the findings were secondary changes, i.e., brain atrophy, or degeneration of the white matter. In the SGE group, the rate was 77.4%, with an almost equal percentage of congenital and secondary changes. Of 255 patients who were examined by electroencephalography (EEG) on the same day as MRI, about 50% showed a correlation between the EEG records and the MRI abnormalities. However, only 8 patients showed a correlation in localization between the EEG and MRI abnormalities. (author)

  10. A study of brain MRI findings in children with epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Kanematsu, Sachiko; Sumida, Sawako; Muto, Ayako; Osawa, Makiko; Ono, Yuko [Tokyo Women' s Medical Coll. (Japan); Uchida, Moriyasu; Maruyama, Hiroshi

    2000-06-01

    Magnetic resonance imaging in the brain was performed in 293 patients with childhood-onset (<15 y.o.) epilepsy who had been classified into 4 groups, idiopathic localization-related epilepsy (ILRE), 78 patients; idiopathic generalized epilepsy (IGE), 116 patients; symptomatic localization-related epilepsy (SLRE), 68 patients and symptomatic generalized epilepsy (SGE), 31 patients, with the Classification of Epilepsies and Epileptic Syndrome (1989 International League Against Epilepsy). The examination was performed with a 1.5 T magnet. One hundred twenty-five patients (42.7%) showed abnormal findings, and the incidence in each group was as follows: Idiopathic epilepsy: The rate of abnormal findings in the ILRE and IGE groups was 21.8% and 20.7%, respectively. Most of the abnormal findings were secondary changes, such as diffuse or localized brain atrophy. Of the congenital abnormalities, the main finding was arachnoid cyst. Symptomatic epilepsy: The rate of abnormality in the SLRE patients was 88.2%, and 85% of the findings were secondary changes, i.e., brain atrophy, or degeneration of the white matter. In the SGE group, the rate was 77.4%, with an almost equal percentage of congenital and secondary changes. Of 255 patients who were examined by electroencephalography (EEG) on the same day as MRI, about 50% showed a correlation between the EEG records and the MRI abnormalities. However, only 8 patients showed a correlation in localization between the EEG and MRI abnormalities. (author)

  11. Heart MRI

    Science.gov (United States)

    Magnetic resonance imaging - cardiac; Magnetic resonance imaging - heart; Nuclear magnetic resonance - cardiac; NMR - cardiac; MRI of the heart; Cardiomyopathy - MRI; Heart failure - MRI; Congenital heart disease - MRI

  12. Ifosfamide in previously untreated disseminated neuroblastoma. Results of Study 3A of the European Neuroblastoma Study Group.

    Science.gov (United States)

    Kellie, S J; De Kraker, J; Lilleyman, J S; Bowman, A; Pritchard, J

    1988-05-01

    A prospective study of the effectiveness of ifosfamide as a single agent in the management of previously untreated patients with Evans stage IV neuroblastoma was undertaken. Eighteen children aged more than 1 year were treated with ifosfamide (IFX) 3 g/m2 daily for 2 days immediately after diagnosis and 3 weeks later. Treatment was continued with combination chemotherapy using vincristine, cyclophosphamide, cisplatinum and etoposide (OPEC) or a variant. Mesna (2-mercaptoethane sulphonate) was given to all patients during IFX treatment to prevent urotoxicity. Eight of the 18 patients (44%) responded to IFX. Nine had greater than 66% reduction in baseline tumor volume. Of 15 evaluable patients with raised pre-treatment urinary catecholamine excretion, six (40%) achieved greater than 50% reduction in pretreatment levels. Two of 10 patients evaluable for bone marrow response had complete clearance. Toxicity was mild in all patients. Upon completing 'first line' therapy, only four patients (22%) achieved a good partial remission (GPR) or complete response (CR). Median survival was 11 months. There was a lower rate of attaining GPR and shortened median survival in patients receiving phase II IFX before OPEC or variant, compared to patients with similar pre-treatment characteristics treated with OPEC from diagnosis in an earlier study.

  13. MRI in patients with portal hypertension (preoperative and postoperative studies). The first 15 cases

    Energy Technology Data Exchange (ETDEWEB)

    Pozzato, A; Cattoni, F; Baldini, U and others

    1987-01-01

    Fifteen patients with portal hypertension were examined by magnetic resonance imaging (MRI) using spin-echo sequences. Sagittal and transaxial images were obtained in all cases. Ten subjects have been evaluated after portosystemic shunt operations (6 portocaval and 4 splenorenal shunts); 5 patients were studied by MRI before shunt placements. Angiographic correlation was obtained in 15 cases. In each of the preoperative examinations, MRI accurately depicted inferior vena cava, portal vein and splenic vein. Shunt patency was documented in 10/10 postoperative studies: portacaval shunts patency was better determined in the transaxial plane while splenorenal shunts were better demonstrted in the sagittal plane. Thus, MRI seems to be an accurate and noninvasive method for detecting portosystemic shunt patency without the use of intravenous contrast media and without patient exposure to radiation.

  14. MRI outcomes with cladribine tablets for multiple sclerosis in the CLARITY study

    DEFF Research Database (Denmark)

    Comi, Giancarlo; Cook, Stuart D; Giovannoni, Gavin

    2013-01-01

    We herein provide a comprehensive assessment of magnetic resonance imaging (MRI) outcomes from CLARITY, a 96-week, double-blind study demonstrating significant clinical and MRI improvements in patients with relapsing-remitting multiple sclerosis (RRMS) treated with cladribine tablets. Patients...... with RRMS were randomized 1:1:1 to annual short-course therapy with cladribine tablets cumulative dose 3.5 or 5.25 mg/kg or placebo. MRI endpoints included mean number of T1 gadolinium-enhancing (Gd+), active T2 and combined unique (CU) lesions/patient/scan. MRI-measured disease activity was significantly...... reduced in both cladribine tablets groups versus placebo. The proportion of patients with no active lesions at study end was: T1 Gd+ lesions: 86.8 and 91.0 versus 48.3 % (p ...

  15. Music and Language Syntax Interact in Broca's Area: An fMRI Study.

    Directory of Open Access Journals (Sweden)

    Richard Kunert

    Full Text Available Instrumental music and language are both syntactic systems, employing complex, hierarchically-structured sequences built using implicit structural norms. This organization allows listeners to understand the role of individual words or tones in the context of an unfolding sentence or melody. Previous studies suggest that the brain mechanisms of syntactic processing may be partly shared between music and language. However, functional neuroimaging evidence for anatomical overlap of brain activity involved in linguistic and musical syntactic processing has been lacking. In the present study we used functional magnetic resonance imaging (fMRI in conjunction with an interference paradigm based on sung sentences. We show that the processing demands of musical syntax (harmony and language syntax interact in Broca's area in the left inferior frontal gyrus (without leading to music and language main effects. A language main effect in Broca's area only emerged in the complex music harmony condition, suggesting that (with our stimuli and tasks a language effect only becomes visible under conditions of increased demands on shared neural resources. In contrast to previous studies, our design allows us to rule out that the observed neural interaction is due to: (1 general attention mechanisms, as a psychoacoustic auditory anomaly behaved unlike the harmonic manipulation, (2 error processing, as the language and the music stimuli contained no structural errors. The current results thus suggest that two different cognitive domains-music and language-might draw on the same high level syntactic integration resources in Broca's area.

  16. Collective Correlations of Brodmann Areas fMRI Study with RMT-Denoising

    OpenAIRE

    Burda, Zdzislaw; Kornelsen, Jennifer; Nowak, Maciej A.; Porebski, Bartosz; Sboto-Frankenstein, Uta; Tomanek, Boguslaw; Tyburczyk, Jacek

    2013-01-01

    We study collective behavior of Brodmann regions of human cerebral cortex using functional Magnetic Resonance Imaging (fMRI) and Random Matrix Theory (RMT). The raw fMRI data is mapped onto the cortex regions corresponding to the Brodmann areas with the aid of the Talairach coordinates. Principal Component Analysis (PCA) of the Pearson correlation matrix for 41 different Brodmann regions is carried out to determine their collective activity in the idle state and in the active state stimulated...

  17. Tactile and non-tactile sensory paradigms for fMRI and neurophysiologic studies in rodents

    OpenAIRE

    Sanganahalli, Basavaraju G.; Bailey, Christopher J.; Herman, Peter; Hyder, Fahmeed

    2009-01-01

    Functional magnetic resonance imaging (fMRI) has become a popular functional imaging tool for human studies. Future diagnostic use of fMRI depends, however, on a suitable neurophysiologic interpretation of the blood oxygenation level dependent (BOLD) signal change. This particular goal is best achieved in animal models primarily due to the invasive nature of other methods used and/or pharmacological agents applied to probe different nuances of neuronal (and glial) activity coupled to the BOLD...

  18. MRI-assisted PET motion correction for neurologic studies in an integrated MR-PET scanner.

    Science.gov (United States)

    Catana, Ciprian; Benner, Thomas; van der Kouwe, Andre; Byars, Larry; Hamm, Michael; Chonde, Daniel B; Michel, Christian J; El Fakhri, Georges; Schmand, Matthias; Sorensen, A Gregory

    2011-01-01

    Head motion is difficult to avoid in long PET studies, degrading the image quality and offsetting the benefit of using a high-resolution scanner. As a potential solution in an integrated MR-PET scanner, the simultaneously acquired MRI data can be used for motion tracking. In this work, a novel algorithm for data processing and rigid-body motion correction (MC) for the MRI-compatible BrainPET prototype scanner is described, and proof-of-principle phantom and human studies are presented. To account for motion, the PET prompt and random coincidences and sensitivity data for postnormalization were processed in the line-of-response (LOR) space according to the MRI-derived motion estimates. The processing time on the standard BrainPET workstation is approximately 16 s for each motion estimate. After rebinning in the sinogram space, the motion corrected data were summed, and the PET volume was reconstructed using the attenuation and scatter sinograms in the reference position. The accuracy of the MC algorithm was first tested using a Hoffman phantom. Next, human volunteer studies were performed, and motion estimates were obtained using 2 high-temporal-resolution MRI-based motion-tracking techniques. After accounting for the misalignment between the 2 scanners, perfectly coregistered MRI and PET volumes were reproducibly obtained. The MRI output gates inserted into the PET list-mode allow the temporal correlation of the 2 datasets within 0.2 ms. The Hoffman phantom volume reconstructed by processing the PET data in the LOR space was similar to the one obtained by processing the data using the standard methods and applying the MC in the image space, demonstrating the quantitative accuracy of the procedure. In human volunteer studies, motion estimates were obtained from echo planar imaging and cloverleaf navigator sequences every 3 s and 20 ms, respectively. Motion-deblurred PET images, with excellent delineation of specific brain structures, were obtained using these 2 MRI

  19. Effects of MRI on the electrophysiology of the motor cortex: a TMS study

    International Nuclear Information System (INIS)

    Schlamann, Marc; Pietrzyk, T.; Yoon, M.S.; Gerwig, M.; Kastrup, O.; Maderwald, S.; Forsting, M.; Ladd, S.C.; Duisburg-Essen Univ.; Bitz, A.; Ladd, M.E.

    2009-01-01

    The increasing spread of high-field and ultra-high-field MRI scanners encouraged a new discussion on safety aspects of MRI examinations. Earlier studies report altered acoustically evoked potentials. This finding was not able to be confirmed in later studies. In the present study transcranial magnetic stimulation (TMS) was used to evaluate whether motor cortical excitability may be altered following MRI examination even at field strength of 1.5 T. In 12 right-handed male volunteers individual thresholds for motor responses and then the length of the post-excitatory inhibition (silent period) were determined. Subsequently the volunteers were examined in the MRI scanner (Siemens Avanto, 1.5 T) for 63 minutes using gradient and spin echo sequences. MRI examination was immediately followed by another TMS session and a third 10 minutes later. As a control condition, the 12 subjects spent one hour in the scanner without examination and one hour on a couch without the presence of a scanner. After MRI examination, the silent period was significantly lengthened in all 12 subjects and then tended to the initial value after 10 min. Motor thresholds were significantly elevated and then normalized after 10 minutes. No significant effects were found in the control conditions. (orig.)

  20. Assessment of swallowing and its disorders—A dynamic MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Vijay Kumar, K.V., E-mail: vijaykumarkv@yahoo.in [Department of Speech, Language and Hearing Sciences, SRU (India); Shankar, V., E-mail: drshankarv@yahoo.co.in [Department of Neurology, SRU (India); Santosham, Roy, E-mail: santoshamroy@yahoo.com [Department of Radiology and Imaging Sciences, SRU (India)

    2013-02-15

    Magnetic resonance imaging overcomes the limitations of videofluoroscopy in assessing without radiation exposure. The clinical utility of dynamic MRI for swallowing disorders is not well documented. This study demonstrates the feasibility of using dynamic MRI in assessment of swallowing disorders. Ten normal and three brainstem lesion patients participated in this study. GE Signa HDxt 1.5 Tesla MRI scanner with head-and-neck coil as a receiver and fast imaging employing steady state acquisition sequence was used. The swallow was analyzed in terms of symmetry and amplitude of movements of velum, faucial pillars, tongue, epiglottis and cricopharyngeous and images from the sagittal, coronal and axial planes. In sagittal plane posterior movement of tongue and its compression on velum, elevation of hyoid bone, elevation of larynx and lid action of epiglottis, in the coronal view the symmetrical movements of the faucial pillars and pharyngeal constrictor muscles and in axial plane three anatomical landmarks were targeted based on their role in swallowing, viz. velum, epiglottis and cricopharyngeous were studied. In brainstem lesion individuals, posterior movement of tongue, and elevation of larynx were not seen. Asymmetrical movements of faucial pillars and cricopharyngeous muscle were appreciated in the dynamic MRI. This demonstrates that, dynamic MRI is an efficient tool to understand the swallowing physiology and helps the speech language pathologist in modifying the swallowing maneuvers. Dynamic MRI is an effective tool in assessing swallowing and its disorders. This muscle specific information is not appreciated in videofluoroscopy and this information is necessary to modify the therapy maneuvers.

  1. Radiography students' clinical placement experiences in MRI: A phenomenological study

    International Nuclear Information System (INIS)

    Portanier Mifsud, Claude; Castillo, Joseph; Portelli, Jonathan Loui

    2015-01-01

    Purpose: The purpose of this study was to gain an insight into radiography students' clinical practice experiences within an MRI unit of a large teaching hospital in Malta. The underlying objectives of the study were to identify and explore the descriptions and meanings of the MRI clinical experiences of students. Methods: Five students, independently undergoing their clinical placements in MRI were asked to write a diary about their daily experiences. Each student then participated in a follow up interview. Data analysis was based on Husserls' phenomenological approach. Results: Eight themes emerged from the data analysed. Students described their experience as one mainly based on observation, where, during their placements, they observed radiographers at work. In this respect, students described their experience as lacking ‘hands on practice’. Students indicated that they felt uncomfortable, unsupervised and unwelcome most of the time. They also expressed the need to feel useful and part of the MRI team during their placement and so they tried to help the team in areas such as patient screening. This helped them build confidence. Learning in MRI was specifically based on the university tasks prescribed and possibly there was no motivation to learn more. The students also described their experience as varied and different when compared to other placements. Conclusion: This study provides a rare insight into radiography students' placement experiences in MRI and should enable the supervising radiographer and educator to obtain a deeper appreciation of the clinical placement experience

  2. Assessment of swallowing and its disorders—A dynamic MRI study

    International Nuclear Information System (INIS)

    Vijay Kumar, K.V.; Shankar, V.; Santosham, Roy

    2013-01-01

    Magnetic resonance imaging overcomes the limitations of videofluoroscopy in assessing without radiation exposure. The clinical utility of dynamic MRI for swallowing disorders is not well documented. This study demonstrates the feasibility of using dynamic MRI in assessment of swallowing disorders. Ten normal and three brainstem lesion patients participated in this study. GE Signa HDxt 1.5 Tesla MRI scanner with head-and-neck coil as a receiver and fast imaging employing steady state acquisition sequence was used. The swallow was analyzed in terms of symmetry and amplitude of movements of velum, faucial pillars, tongue, epiglottis and cricopharyngeous and images from the sagittal, coronal and axial planes. In sagittal plane posterior movement of tongue and its compression on velum, elevation of hyoid bone, elevation of larynx and lid action of epiglottis, in the coronal view the symmetrical movements of the faucial pillars and pharyngeal constrictor muscles and in axial plane three anatomical landmarks were targeted based on their role in swallowing, viz. velum, epiglottis and cricopharyngeous were studied. In brainstem lesion individuals, posterior movement of tongue, and elevation of larynx were not seen. Asymmetrical movements of faucial pillars and cricopharyngeous muscle were appreciated in the dynamic MRI. This demonstrates that, dynamic MRI is an efficient tool to understand the swallowing physiology and helps the speech language pathologist in modifying the swallowing maneuvers. Dynamic MRI is an effective tool in assessing swallowing and its disorders. This muscle specific information is not appreciated in videofluoroscopy and this information is necessary to modify the therapy maneuvers

  3. MRI STUDY OF TYPES AND INCIDENCE OF INTERNAL DERANGEMENTS OF TRAUMATIC KNEE JOINT

    Directory of Open Access Journals (Sweden)

    Bomidi Sudha Rani

    2016-12-01

    Full Text Available BACKGROUND MRI has been accepted as the best imaging modality for noninvasive evaluation of knee injuries and it has proved reliable, safe and offers advantages over diagnostic arthroscopy, which is currently regarded as the reference standard for the diagnosis of internal derangements of the knee. 1 METHODS AND MATERIALS A prospective study of fifty patients who underwent MRI for the diagnosis of internal derangement of knee was conducted between the period of January 2015 to January 2016 in Government General Hospital, Kakinada. All the patients with history of knee joint pain following trauma and clinically suspected to have meniscal and ligament tears are included in the study. Patients were evaluated using GE 1.5 T MRI machine with pulsar gradient system using a sensor extremity coil. RESULTS Commonest lesion detected in our study was ACL tear followed by medial meniscal tear and medial collateral ligament injury. The most common sign of cruciate ligament injury was hyperintensity in the ligament. Grade 3 was the most common grade of meniscal tear. CONCLUSION MRI is an excellent, noninvasive, radiation free imaging modality and is unique in its ability to evaluate the internal structure as well as soft tissue delineation. Many anatomical variants can mimic a tear on MRI. MRI is an excellent noninvasive modality for imaging the knee and helps in arriving at a correct anatomical diagnosis there by guiding further management of the patient.

  4. Prevalence of lateral ventricle asymmetry in brain MRI studies of neurologically normal dogs and dogs with idiopathic epilepsy.

    Science.gov (United States)

    Pivetta, Mauro; De Risio, Luisa; Newton, Richard; Dennis, Ruth

    2013-01-01

    Asymmetry of the cerebral lateral ventricles is a common finding in cross-sectional imaging of otherwise normal canine brains and has been assumed to be incidental. The purpose of this retrospective study was to compare the prevalence of ventricular asymmetry in brain MRI studies of normal dogs and dogs with idiopathic epilepsy. Brain MRI archives were searched for 100 neurologically normal dogs (Group 1) and 100 dogs with idiopathic epilepsy (Group 2). For each dog, asymmetry of the lateral ventricles was subjectively classified as absent, mild, moderate, and severe based on a consensus of two observers who were unaware of group status. Ventricular areas were measured from transverse T1W images at the level of the interthalamic adhesion. An asymmetry ratio was calculated as the ratio of the larger to smaller ventricular transverse area. There was excellent agreement between subjective assessments of ventricular asymmetry and quantitative assessments using asymmetry ratios (k = 0.995). The prevalence of asymmetry was 38% in Group 1 dogs and 44% in Group 2 dogs. Assymmetry was scored as mild in the majority of Group 2 dogs. There was no significant association between presence/absence and degree of ventricular asymmetry vs. dog group, age, gender, or skull conformation. Findings from the current study supported previously published assumptions that asymmetry of the lateral cerebral ventricles is an incidental finding in MRI studies of the canine brain. © 2013 Veterinary Radiology & Ultrasound.

  5. Shoulder-Mounted Robot for MRI-guided arthrography: Accuracy and mounting study.

    Science.gov (United States)

    Monfaredi, R; Wilson, E; Sze, R; Sharma, K; Azizi, B; Iordachita, I; Cleary, K

    2015-08-01

    A new version of our compact and lightweight patient-mounted MRI-compatible 4 degree-of-freedom (DOF) robot for MRI-guided arthrography procedures is introduced. This robot could convert the traditional two-stage arthrography procedure (fluoroscopy-guided needle insertion followed by a diagnostic MRI scan) to a one-stage procedure, all in the MRI suite. The results of a recent accuracy study are reported. A new mounting technique is proposed and the mounting stability is investigated using optical and electromagnetic tracking on an anthropomorphic phantom. Five volunteer subjects including 2 radiologists were asked to conduct needle insertion in 4 different random positions and orientations within the robot's workspace and the displacement of the base of the robot was investigated during robot motion and needle insertion. Experimental results show that the proposed mounting method is stable and promising for clinical application.

  6. Test-retest reliability of an fMRI paradigm for studies of cardiovascular reactivity.

    Science.gov (United States)

    Sheu, Lei K; Jennings, J Richard; Gianaros, Peter J

    2012-07-01

    We examined the reliability of measures of fMRI, subjective, and cardiovascular reactions to standardized versions of a Stroop color-word task and a multisource interference task. A sample of 14 men and 12 women (30-49 years old) completed the tasks on two occasions, separated by a median of 88 days. The reliability of fMRI BOLD signal changes in brain areas engaged by the tasks was moderate, and aggregating fMRI BOLD signal changes across the tasks improved test-retest reliability metrics. These metrics included voxel-wise intraclass correlation coefficients (ICCs) and overlap ratio statistics. Task-aggregated ratings of subjective arousal, valence, and control, as well as cardiovascular reactions evoked by the tasks showed ICCs of 0.57 to 0.87 (ps reliability. These findings support using these tasks as a battery for fMRI studies of cardiovascular reactivity. Copyright © 2012 Society for Psychophysiological Research.

  7. Study of breast implant rupture: MRI versus surgical findings.

    Science.gov (United States)

    Vestito, A; Mangieri, F F; Ancona, A; Minervini, C; Perchinunno, V; Rinaldi, S

    2012-09-01

    This study evaluated the role of breast magnetic resonance (MR) imaging in the selective study breast implant integrity. We retrospectively analysed the signs of breast implant rupture observed at breast MR examinations of 157 implants and determined the sensitivity and specificity of the technique in diagnosing implant rupture by comparing MR data with findings at surgical explantation. The linguine and the salad-oil signs were statistically the most significant signs for diagnosing intracapsular rupture; the presence of siliconomas/seromas outside the capsule and/or in the axillary lymph nodes calls for immediate explantation. In agreement with previous reports, we found a close correlation between imaging signs and findings at explantation. Breast MR imaging can be considered the gold standard in the study of breast implants.

  8. Pediatric MRI

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NIH Study of Normal Brain Development is a longitudinal study using anatomical MRI, diffusion tensor imaging (DTI), and MR spectroscopy (MRS) to map pediatric...

  9. A clinical study in elderly patients with Parkinson's disease using MRI and SPECT

    International Nuclear Information System (INIS)

    Umahara, Takahiko; Iwamoto, Toshihiko; Takasaki, Masaru; Katsunuma, Hideyo

    1991-01-01

    Parkinson's disease (PD) is often associated with dementia in elderly patients, and sometimes PD coexists with senile dementia of the Alzheimer type (SDAT) or cerebrovascular disease (CVD) in the elderly. However, since there are few previous clinical studies on the coincidence of, or relationship between PD and CVD, the authors evaluated these aspects in 34 elderly patients with PD using MRI and SPECT. All the patients were over 70 years old. The diagnosis of PD was based on the presence of three symptons (resting tremor, cogwheel rigidity and bradikinesia) which are characteristic of PD, and the effectiveness of L-DOPA therapy. We therefore believe that patients with vascular Parkinsonism were excluded from our study. In 34 cases, 24 (71%) had MRI evidence of CVD (mainly the lacunar state). In the 10 cases who had no CVD, 2 (20%) had severe dementia and the decrease of regional cerebral blood flow (rCBF) in the temporal and parietal lobes bilaterally correlated with the SPECT findings commonly found in SDAT. A comparison of the rCBF and the results of Hasegawa's dementia score (HDS) (verbal intelligence score) was made between the patients with PD associated with CVD and the patients with PD who had no CVD and no SPECT findings which correlated with SDAT. The rCBF in the frontal lobes and the results of the HDS of the former group were significantly lower than those of the latter. As mentioned above, elderly patients with PD often had CVD, leading to dementia. We also pointed out the difficulty in making a differential diagnosis between PD with CVD and vascular Parkinsonism, and the necessity of whether or not the concept of 'mixed type Parkinsonism' should be considered. (author)

  10. Central Pain Processing in Early-Stage Parkinson's Disease: A Laser Pain fMRI Study.

    Directory of Open Access Journals (Sweden)

    Christine Petschow

    Full Text Available Pain is a common non-motor symptom in Parkinson's disease. As dopaminergic dysfunction is suggested to affect intrinsic nociceptive processing, this study was designed to characterize laser-induced pain processing in early-stage Parkinson's disease patients in the dopaminergic OFF state, using a multimodal experimental approach at behavioral, autonomic, imaging levels.13 right-handed early-stage Parkinson's disease patients without cognitive or sensory impairment were investigated OFF medication, along with 13 age-matched healthy control subjects. Measurements included warmth perception thresholds, heat pain thresholds, and central pain processing with event-related functional magnetic resonance imaging (erfMRI during laser-induced pain stimulation at lower (E = 440 mJ and higher (E = 640 mJ target energies. Additionally, electrodermal activity was characterized during delivery of 60 randomized pain stimuli ranging from 440 mJ to 640 mJ, along with evaluation of subjective pain ratings on a visual analogue scale.No significant differences in warmth perception thresholds, heat pain thresholds, electrodermal activity and subjective pain ratings were found between Parkinson's disease patients and controls, and erfMRI revealed a generally comparable activation pattern induced by laser-pain stimuli in brain areas belonging to the central pain matrix. However, relatively reduced deactivation was found in Parkinson's disease patients in posterior regions of the default mode network, notably the precuneus and the posterior cingulate cortex.Our data during pain processing extend previous findings suggesting default mode network dysfunction in Parkinson's disease. On the other hand, they argue against a genuine pain-specific processing abnormality in early-stage Parkinson's disease. Future studies are now required using similar multimodal experimental designs to examine pain processing in more advanced stages of Parkinson's disease.

  11. Carbamazepine reduces memory induced activation of mesial temporal lobe structures: a pharmacological fMRI-study

    Directory of Open Access Journals (Sweden)

    Okujava Michael

    2001-11-01

    Full Text Available Abstract Background and Purpose It is not known whether carbamazepine (CBZ; a drug widely used in neurology and psychiatry influences the blood oxygenation level dependent (BOLD contrast changes induced by neuronal activation and measured by functional MRI (fMRI. We aimed to investigate the influence of CBZ on memory induced activation of the mesial temporal lobes in patients with symptomatic temporal lobe epilepsy (TLE. Material and Methods Twenty-one individual patients with refractory symptomatic TLE with different CBZ serum levels and 20 healthy controls were studied using BOLD fMRI. Mesial temporal lobe (MTL activation was induced by a task that is based on the retrieval of individually familiar visuo-spatial knowledge. The extent of significant MTL fMRI activation was measured and correlated with the CBZ serum level. Results In TLE patients, the extent of significant fMRI activation over both MTL was negatively correlated to the CBZ serum level (Spearman r = -0.654, P Conclusions In TLE patients, carbamazepine reduces the fMRI-detectable changes within the mesial temporal lobes as induced by effortful memory retrieval. FMRI appears to be suitable to study the effects of chronic drug treatment in patients with epilepsy.

  12. Uterine leiomyoma: comparative study with MRI and histopathology

    International Nuclear Information System (INIS)

    Zhang Rong; Liang Biling; Fu Jiaping; Li Yong; Shen Jun

    2003-01-01

    Objective: To compare MRI findings of uterine leiomyomas with histologic subtypes, and to evaluate the value of enhanced MRI in differentiating leiomyoma subtypes. Methods: Forty-two cases of uterine leiomyomas with MRI and pathology were analyzed between 1998 and 2002. 101 uterine leiomyomas were analyzed. 34 cases were examined with Philips T5-II super-conducting magnetic resonance system (0.5T) using surface coil and 8 cases with Philips Intera 1.5 T super-conducting magnetic resonance system using body phase array coil. Plain scan were acquired with SE T 1 -weighted imaging and TSE T 2 -weighted imaging. Conventional contrast imaging was obtained with SE T 1 -weighted imaging after iv injection of Gd-DTPA (0.1mmol/kg). MR features were observed and compared with that of the pathological types. Results: Almost all the leiomyomas showed slight hypointensity or isointensity on T 1 -weighted images. Most ordinary (97%) leiomyomas displayed hypointensity on T 2 -weighted images. Most cellular (75%) and degenerated (55%) leiomyomas manifested as hyperintensity on T 2 -weighted images. The signal intensity was not statistically different between cellular leiomyomas and degenerated leiomyomas (χ 2 =4.192, P>0.05). However, there was a statistically significant difference in the signal intensity on T 2 -weighted images between ordinary leiomyomas and cellular or degenerated leiomyomas (χ 2 =81.564, P<0.05). The signal homogeneity was statistically different in leiomyomas among different pathological types. Three patterns of enhancement occurred in ordinary leiomyomas, but mostly showed homogeneously enhanced. Most cellular leiomyomas showed homogenous enhancement, the degenerated leiomyomas mostly displayed peripheral and mild enhancement. Conclusion: The signal intensity on MR imaging was different in leiomyomas with different pathological subtype. The Gd-DTPA enhanced scans was not indispensable for the diagnosis and detection of leiomyomas, but it can help to

  13. Knee joint anterior malalignment and patellofemoral osteoarthritis: an MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Tsavalas, Nikolaos; Karantanas, Apostolos H. [University Hospital, University of Crete, Department of Medical Imaging, Heraklion, Crete (Greece); Katonis, Pavlos [University Hospital, University of Crete, Department of Orthopaedic Surgery, Heraklion, Crete (Greece)

    2012-02-15

    To evaluate patellofemoral congruency measurements on MRI and correlate the findings with severity of ipsilateral osteoarthritis. We retrospectively reviewed 650 consecutive knee MRI examinations from 622 patients divided into two age groups: {<=}50 and >50 year-old. The femoral sulcus angle (SA) and depth (SD), lateral patellar displacement (LPD), lateral patellofemoral angle (LPFA), tibial tubercle-trochlear groove (TT-TG) distance and Insall-Salvati index as well as the grade of focal cartilage defects (ranging from I to IV) in the patellofemoral region were assessed in each subject on axial and sagittal fat-saturated intermediate-w MR images. A significant difference exists between normal and knees with patellofemoral joint osteoarthritis regarding SA (p = 0.0002 and <0.0001), SD (p = 0.0004 and <0.0001), LPD (p = 0.0014 and 0.0009) and LPFA (p = 0.0002 and 0.0003) in both age groups ({<=}50 and >50 respectively). Significant correlation was found between grading of cartilage defects and SA (rho = 0.21, p = 0.0001 and 0.443, <0.0001), SD (rho = -0.198, p = 0.0003 and -0.418, <0.0001), LPD (rho = 0.176, p = 0.0013 and 0.251, 0.0002) and LPFA (rho = -0.204, p = 0.0002 and -0.239, 0.0005) in both age groups. Knee joint anterior malalignment is multivariably associated with patellofemoral osteoarthritis. circle MRI is an excellent method to evaluate knee alignment and articular cartilage damage. (orig.)

  14. Study of MRI characteristics of newborn bilirubin encephalopathy

    International Nuclear Information System (INIS)

    Wu Wulin; Wang Xiaoyi; Liao Weihua; Liu Fan; Zhang Ping

    2008-01-01

    Objective: To explore routine magnetic resonance imaging characteristics of newborn bilirubin encephalopathy (NBE). Methods: MRI features and clinical data of 17 patients with Newborn bilirubin encephalopathy were retrospectively analyzed, globus pallidus (GP)and subthalamic signal intensity was evaluated. The increase of GP signal intensity and serum total bilirubin peak value were analyzed using pearson correlation analysis. Serum total bilirubin peak value between patients with high signal in the subthalamic nuclei on T 1 WI and patients without high signal in the subthalamic nuclei were compared statistically. Results: The main MRI presentation in the NBE group was abnormally increased signal intensity in the GP on T 1 WI, which was not apparent on T 2 WI. One patient showed abnormal high signal intensity in the posteromedial part of GP. Nine patients had high signal in the subthalamic nuclei on T 1 WI and normal signal on T 2 WI. Four patients showed high signal in the brainstem with sparing of dorsal pontine. The increase in value of GP signal intensity was 249.0-423.8 in 12 patients and their serum total bilirubin peak values were 366.0-983.3 μmol/L. A positive correlation was found between increase of GP signal intensity and serum total bilirubin peak value. The serum total bilirubin level of abnormal subthalamic group and normal subthalamic group were 660.7±192.4 μmol/L and 513.3±107.51 μmol/L respectively. The difference between the two groups was not statistically significant (t=1.914, P>0.05). Conclusion: The routine MRI has some characteristics and is useful in the diagnosis of newborn bilirubin encephalopathy. (authors)

  15. Experimental study of MRI signal changes of calcification

    International Nuclear Information System (INIS)

    Gong Xiangyang; Li Senhua; Li Rongfen; Hong Xiang; Gong Xiaoya; Xu Fengfeng

    1999-01-01

    Objective: To evaluate MRI signal changes according to different calcium compound, concentration and proportion, and try to give an reasonable explanation. Methods: Sixty samples composed of different calcium powders, various concentration and proportion of calcium were examined with CT and MRI. Five different calcium particles were evaluated with scanning electron microscopy. Results: (1) CT value of calcium gradually increased as the concentration increased; (2) CaSO 4 ·H 2 O was similar to CaCO 3 in terms of MRI T 1 WI signal intensity (P > 0.05); (3) Ca 3 (PO 4 ) 2 and Ca(OH) 2 showed hyperintensity in T 1 WI and was higher than other calcium salts (P 1 WI signal intensity of Ca 3 (PO 4 ) 2 / and Ca(OH) 2 showed biphasic curves with their peaks at 0.3 g/ml; (5) T 2 WI signal intensity of all series of calcium decreased as the concentration increased; (6) Signal intensity of mixed Ca 3 (PO 4 ) 2 /CaCO 3 was higher than CaHPO 4 ·2H 2 O/CaCO 3 on T 1 WI and lower on T 2 WI (P 3 , CaHPO 4 ·2H 2 O and CaSO 4 ·2H 2 O showed regular crystal shapes and smooth surface under scanning electron microscopy, but Ca 3 (PO 4 ) 2 and Ca(OH) 2 displayed their irregular figures and rough surface. Conclusions: Calcifications show variable MR signal due to difference of calcium compounds, various concentration and proportion of calcium. Understanding of these finding will help interpretation of MR images more precisely

  16. Clinical studies of cerebral arteriosclerosis in diabetic subjects. Analysis with brain MRI study

    International Nuclear Information System (INIS)

    Ohashi, Makoto; Tanahashi, Hideo; Nomura, Makoto; Yamada, Yoshio; Abe, Hiroshi.

    1994-01-01

    In order to investigate the clinical characteristics of cerebral arteriosclerosis in diabetic subjects, brain MRI studies were conducted in diabetic patients and healthy subjects. The subjects were 93 diabetic patients without symptoms and signs of cerebral infarction (49 males and 44 females) with a mean age of 59 years and 73 healthy subjects (43 males and 30 females) with a mean age of 57 years. The MRI studies were performed on a General Electric 1.5-T signa system. The spin-echo technique (T2-weighted image) was used with a pulse repetition time (TR) of 2,500 msec and echo time (TE) of 80 msec. The quantitative evaluation of cerebral infarction was assessed using personal computer and image-scanner. By MRI, the incidence of cerebral infarction in diabetic patients was significantly higher than that in healthy subjects (30.1% vs. 13.7%, respectively, p<0.05). The mean age of the diabetic patients with cerebral infarctions was higher than that of those without cerebral infarctions. Hypertension and diabetic nephropathy were present more frequently in the subjects with cerebral infarctions. These data suggest that it is important to delay the onset and slow the progression of cerebral infarction in diabetic patients by strict blood glucose control and management of blood pressure. (author)

  17. White matter lesions in psychiatric patients: a retrospective MRI study

    International Nuclear Information System (INIS)

    Becker, T.; Teichmann, E.; Hofmann, E.; Schmidtke, A.; Warmuth-Metz, M.; Nadjmi, M.

    1992-01-01

    T2-weighted MRI scans of psychiatric patients with at least one white matter lesion (WML) were compared to 83 non-psychiatric controls with respect to WML number and distribution. MANOVA resulted in significant effects for sex, age and patient group with respect to WML number. In the psychiatric patients, infratentorial WML prevailed in organic psychoses. WML number was positively correlated with age with the exception of right temporal lobe WML. Based on WML spatial distribution, four patient clusters were found. Clusters with widely distributed WML comprised older patients with late onset of illness; right frontal and temporal WML were associated with mania, euphoria and unstable mood. (orig.)

  18. Adherence to MRI protocol consensus guidelines in multiple sclerosis: an Australian multi-centre study

    International Nuclear Information System (INIS)

    Curley, Michael; Josey, Lawrence; Lucas, Robyn; Dear, Keith; Taylor, Bruce V.; Coulthard, Alan; Ausimmune Investigator Group

    2012-01-01

    Multiple sclerosis (MS) is a debilitating disease that causes significant morbidity within a young demographic. Diagnostic guidelines for MS have evolved, and imaging has played an increasingly important role in diagnosis over the last two decades. For imaging to contribute to diagnosis in a meaningful way, it must be reproducible. Consensus guidelines for MRI in MS exist to define correct sequence type and imaging technique, but it is not clear to what extent they are followed. This study reviewed MRI studies performed on Australian individuals presenting with a first clinical diagnosis of central nervous system demyelination (FCD) for adherence to published guidelines and discussed practical implementation of MS guidelines in light of recent updates. The Ausimmune study was a prospective case control study of Australian participants presenting with FCD from 2003 to 2006. Baseline cranial and spinal cord MRI studies of 226 case participants from four separate Australian regions were reviewed. MRI sequences were classified according to anatomical location, slice plane, tissue weighting and use of gadolinium-containing contrast media. Results were compared with the 2003 Consortium of Multiple Sclerosis Centres MRI protocol for the diagnosis of MS. The composition of core cranial MRI sequences performed varied across the 226 scans. Of the studies, 91% included sagittal fluid attenuated inversion recovery (FLAIR) sequences. Cranial axial T2-weighted, axial FLAIR and axial proton density-weighted sequences were performed in 88%, 60% and 16% (respectively) of scans. Only 25% of the studies included a T1-weighted contrast-enhanced sequence. Concordance with the guidelines in all sequences was very low (2). Only a small number of MRI investigations performed included all of the sequences stipulated by consensus guidelines. This is likely due to poor awareness in the imaging community of the guidelines and the rationale behind certain sequences. Radiologists with a sub

  19. Presurgical mapping with functional MRI. Comparative study with transcranial magnetic stimulation and intraoperative mapping

    Energy Technology Data Exchange (ETDEWEB)

    Kaminogo, Makio; Morikawa, Minoru; Ishimaru, Hideki; Ochi, Makoto; Onizuka, Masanori; Shirakawa, Yasushi; Takahashi, Haruki; Shibata, Shobu [Nagasaki Univ. (Japan). School of Medicine

    1999-05-01

    The thumb movement was evoked by transcranical magnetic stimulation (TCS) for the mapping of the motor cortex. After the placement of the marker determined by TCS on the scalp, fMRI under motor tasks consisting of repetitive grasping was performed. For motor cortex activation, an axial oblique plane to maximize gray matter sampling in the rolandic cortex was employed in order to compare these different mapping techniques more precisely. Sixteen patients with brain tumors were included in this study. In nine patients, fMRI disclosed activation in one restricted gyrus or in the localized area around one restricted sulcus. Of these nine patients, preoperative TCS mapping corresponded closely with fMRI in six, while in the remaining three, the TCS marker fell between 1 and 2 cm apart from the fMRI-activated area. However, in these three patients, intraoperative electrocortical stimulation corresponded with the preoperative mapping with fMRI. In six patients, contiguous two gyri were activated by motor tasks. The TCS marker was disclosed on one of the two activated gyri. Of these six patients, the position of the TCS marker and fMRI-activated site corresponded with each other in four cases. They were found on the same gyrus but there was 1.0-2.0 cm distance between them in two cases. Intraoperative somatosensory evoked potential was monitored in two of these six cases. They corresponded well with the mapping by fMRI and TCS together. In only one patient, no significant activation area was obtained by fMRI because of excessive head motion during motor tasks. The TCS maker in this patients was identical with intraoperative electro-cortical stimulation mapping. (K.H.)

  20. Presurgical mapping with functional MRI. Comparative study with transcranial magnetic stimulation and intraoperative mapping

    International Nuclear Information System (INIS)

    Kaminogo, Makio; Morikawa, Minoru; Ishimaru, Hideki; Ochi, Makoto; Onizuka, Masanori; Shirakawa, Yasushi; Takahashi, Haruki; Shibata, Shobu

    1999-01-01

    The thumb movement was evoked by transcranical magnetic stimulation (TCS) for the mapping of the motor cortex. After the placement of the marker determined by TCS on the scalp, fMRI under motor tasks consisting of repetitive grasping was performed. For motor cortex activation, an axial oblique plane to maximize gray matter sampling in the rolandic cortex was employed in order to compare these different mapping techniques more precisely. Sixteen patients with brain tumors were included in this study. In nine patients, fMRI disclosed activation in one restricted gyrus or in the localized area around one restricted sulcus. Of these nine patients, preoperative TCS mapping corresponded closely with fMRI in six, while in the remaining three, the TCS marker fell between 1 and 2 cm apart from the fMRI-activated area. However, in these three patients, intraoperative electrocortical stimulation corresponded with the preoperative mapping with fMRI. In six patients, contiguous two gyri were activated by motor tasks. The TCS marker was disclosed on one of the two activated gyri. Of these six patients, the position of the TCS marker and fMRI-activated site corresponded with each other in four cases. They were found on the same gyrus but there was 1.0-2.0 cm distance between them in two cases. Intraoperative somatosensory evoked potential was monitored in two of these six cases. They corresponded well with the mapping by fMRI and TCS together. In only one patient, no significant activation area was obtained by fMRI because of excessive head motion during motor tasks. The TCS maker in this patients was identical with intraoperative electro-cortical stimulation mapping. (K.H.)

  1. Inexperienced clinicians can extract pathoanatomic information from MRI narrative reports with high reproducability for use in research/quality assurance

    DEFF Research Database (Denmark)

    Kent, Peter; Briggs, Andrew M; Albert, Hanne Birgit

    2011-01-01

    Background Although reproducibility in reading MRI images amongst radiologists and clinicians has been studied previously, no studies have examined the reproducibility of inexperienced clinicians in extracting pathoanatomic information from magnetic resonance imaging (MRI) narrative reports and t...

  2. EEG-fMRI Bayesian framework for neural activity estimation: a simulation study

    Science.gov (United States)

    Croce, Pierpaolo; Basti, Alessio; Marzetti, Laura; Zappasodi, Filippo; Del Gratta, Cosimo

    2016-12-01

    Objective. Due to the complementary nature of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), and given the possibility of simultaneous acquisition, the joint data analysis can afford a better understanding of the underlying neural activity estimation. In this simulation study we want to show the benefit of the joint EEG-fMRI neural activity estimation in a Bayesian framework. Approach. We built a dynamic Bayesian framework in order to perform joint EEG-fMRI neural activity time course estimation. The neural activity is originated by a given brain area and detected by means of both measurement techniques. We have chosen a resting state neural activity situation to address the worst case in terms of the signal-to-noise ratio. To infer information by EEG and fMRI concurrently we used a tool belonging to the sequential Monte Carlo (SMC) methods: the particle filter (PF). Main results. First, despite a high computational cost, we showed the feasibility of such an approach. Second, we obtained an improvement in neural activity reconstruction when using both EEG and fMRI measurements. Significance. The proposed simulation shows the improvements in neural activity reconstruction with EEG-fMRI simultaneous data. The application of such an approach to real data allows a better comprehension of the neural dynamics.

  3. A neurotological study of patients with pontine hyperintense lesions on T2 weighted MRI

    International Nuclear Information System (INIS)

    Seo, Toru; Tominaga, Satoru; Yukimasa, Akiko; Oku, Masaya; Sakagami, Masafumi

    2002-01-01

    Pontine hyperintense lesions seen on T2-weighted MRI were thought to be related to disequilibrium. Some of these lesions have a low signal on T1-weighted imaging, while others have an iso-signal. The purpose of this study was to clarify the relationship between neurological findings and pontine lesions detected by MRI. The subjects were 11 patients (6 males, 5 females; age range: 30 to 83 years [mean: 64.1 years]) with pontine hyperintense lesions identified on T2-weighted MRI. We compared the clinical signs and the MRI findings. Six of the patients had low-intensity areas on T1-weighted images, and the other 5 had iso-intensity areas. Six patients complained of vertigo, and 5 complained of dizziness. Eight complained of positionaly evoked disequilibrium. Positional nystagmus was seen in 4 patients. In 9 patients, abnormalities were found on the ENG test, including the saccadic eye movement test, ETT, and OKP. Numbness on the lips occurred in 2 patients, and cerebellar signs were present in 4. None of the patients had facial paralysis. Disequilibrium originating in the central nervous system was suggested in 10 patients. Clinical examinations revealed similar findings in patients with a low signal on T1-weighted MRI and those with an iso-signal. Our results indicate that pontine lesions identified by T2-weighted MRI cause vertigo or dizziness, and, in most cases, these lesions cause abnormal neurological or neurological abnormalities. (author)

  4. A neurotological study of patients with pontine hyperintense lesions on T2 weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Toru; Tominaga, Satoru; Yukimasa, Akiko; Oku, Masaya; Sakagami, Masafumi [Hyogo Coll. of Medicine, Nishinomiya (Japan)

    2002-03-01

    Pontine hyperintense lesions seen on T2-weighted MRI were thought to be related to disequilibrium. Some of these lesions have a low signal on T1-weighted imaging, while others have an iso-signal. The purpose of this study was to clarify the relationship between neurological findings and pontine lesions detected by MRI. The subjects were 11 patients (6 males, 5 females; age range: 30 to 83 years [mean: 64.1 years]) with pontine hyperintense lesions identified on T2-weighted MRI. We compared the clinical signs and the MRI findings. Six of the patients had low-intensity areas on T1-weighted images, and the other 5 had iso-intensity areas. Six patients complained of vertigo, and 5 complained of dizziness. Eight complained of positionaly evoked disequilibrium. Positional nystagmus was seen in 4 patients. In 9 patients, abnormalities were found on the ENG test, including the saccadic eye movement test, ETT, and OKP. Numbness on the lips occurred in 2 patients, and cerebellar signs were present in 4. None of the patients had facial paralysis. Disequilibrium originating in the central nervous system was suggested in 10 patients. Clinical examinations revealed similar findings in patients with a low signal on T1-weighted MRI and those with an iso-signal. Our results indicate that pontine lesions identified by T2-weighted MRI cause vertigo or dizziness, and, in most cases, these lesions cause abnormal neurological or neurological abnormalities. (author)

  5. Clinical Study Preoperative Evaluation with f MRI of Patients with Intracranial Gliomas Ioannis

    International Nuclear Information System (INIS)

    Kapsalakis, Z.; Hadjigeorgiou, G.; Papadimitriou, A.; Kapsalaki, E.Z.; Fezoulidis, I.; Gotsis, E.D.; Verganelakis, D.; Toulas, P.; Chung, I.; Robinson, J.S.; Lee, J.P.; Fountas, K.N.; Fountas, K.N.

    2012-01-01

    Aggressive surgical resection constitutes the optimal treatment for intracranial gliomas. However, the proximity of a tumor to eloquent areas requires exact knowledge of its anatomic relationships to functional cortex. The purpose of our study was to evaluate f MRI’s accuracy by comparing it to intraoperative cortical stimulation (DCS) mapping. Material and Methods. Eighty-seven patients, with presumed glioma diagnosis, underwent preoperative fMRI and intraoperative DCS for cortical mapping during tumor resection. Findings of fMRI and DCS were considered concordant if the identified cortical centers were less than 5 mm apart. Pre and postoperative Karnofsky Performance Scale and Spitzer scores were recorded. A postoperative MRI was obtained for assessing the extent of resection. Results. The areas of interest were identified by f MRI and DCS in all participants. The concordance between f MRI and Dncs was 91.9% regarding sensory-motor cortex, 100% for visual cortex, and 85.4% for language. Data analysis showed that patients with better functional condition demonstrated higher concordance rates, while there also was a weak association between tumor grade and concordance rate. The mean extent of tumor resection was 96.7%. Conclusions. Functional MRI is a highly accurate preoperative methodology for sensory-motor mapping. However, in language mapping, DCS remains necessary for accurate localization

  6. MRI assessment of thoracic stent grafts after emergency implantation in multi trauma patients: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Rasche, Volker [University Hospital Ulm, Department of Internal Medicine II, Ulm (Germany); University Hospital Ulm, University of Ulm, Department of Internal Medicine II, Ulm (Germany); Oberhuber, Alexander; Orend, Karl-Heinz [University Hospital Ulm, Department of Vascular and Thoracic Surgery, Ulm (Germany); Trumpp, Stephan [University Hospital Ulm, Department of Internal Medicine II, Ulm (Germany); University Hospital Ulm, Department of Vascular and Thoracic Surgery, Ulm (Germany); Bornstedt, Axel; Merkle, Nico; Rottbauer, Wolfgang [University Hospital Ulm, Department of Internal Medicine II, Ulm (Germany); Hoffmann, Martin [University Hospital Ulm, Department of Diagnostic and Interventional Radiology, Ulm (Germany)

    2011-07-15

    To evaluate the feasibility of MRI for static and dynamic assessment of the deployment of thoracic aortic stent grafts after emergency implantation in trauma patients. Twenty patients initially presenting with a rupture of the thoracic aorta were enrolled in this study. All patients underwent thoracic endovascular aortic repair (TEVAR). The deployment of the implanted stent graft was assessed by CTA and MRI, comprising the assessment of the aortic arch with and without contrast agent, and the assessment of the motion of the stent graft over the cardiac cycle. The stent graft geometry and motion over the cardiac cycle were assessable by MRI in all patients. Flow-mediated signal variations in areas of flow acceleration could be well visualised. No statistically significant differences in stent-graft diameters were observed between CT and MRI measurements. MRI appears to be a valuable tool for the assessment of thoracic stent grafts. It shows similar performance in the accurate assessment of stent-graft dimensions to the current gold standard CTA. Its capability of providing additional functional information and the lack of ionising radiation and nephrotoxic contrast agents may make MRI a valuable tool for monitoring patients after TEVAR. (orig.)

  7. Sonographic and MRI evaluation of the plantar plate: a prospective study

    International Nuclear Information System (INIS)

    Gregg, Julie; Silberstein, Morry; Schneider, Timothy; Marks, Paul

    2006-01-01

    The purpose of this study was to establish the accuracy of ultrasound in the examination of the plantar plate by comparing it with MRI, or if available, surgical findings. The lesser metatarsophalangeal joint plantar plates of 40 symptomatic and 40 asymptomatic feet (160 asymptomatic and 160 symptomatic plantar plates) were examined with ultrasound and MRI. Patients treated with surgery were chosen on a clinical basis and provided surgical correlation for the imaging techniques. Symptomatic patients with metatatarsalgia and suspected metatarsophalangeal joint instability were referred by an orthopedic foot specialist; asymptomatic feet were obtained either through examination of the contralateral foot of the symptomatic patients or volunteers. Ultrasound detected 75/160 and 139/160 plantar plates torn in the asymptomatic and symptomatic groups, respectively. MRI detected 56/160 and 142/160 tears in the symptomatic and asymptomatic groups, respectively. The sensitivity of MRI and ultrasound with surgical correlation was calculated to be 87 and 96%, respectively, with poor specificity. Ultrasound correlates moderately with MRI in the evaluation of the plantar plate. Surgical correlations, although limited (n=10), indicate ultrasound is superior to MRI with more accurate detection of tears. (orig.)

  8. Brain Activity Associated with Emoticons: An fMRI Study

    Science.gov (United States)

    Yuasa, Masahide; Saito, Keiichi; Mukawa, Naoki

    In this paper, we describe that brain activities associated with emoticons by using fMRI. In communication over a computer network, we use abstract faces such as computer graphics (CG) avatars and emoticons. These faces convey users' emotions and enrich their communications. However, the manner in which these faces influence the mental process is as yet unknown. The human brain may perceive the abstract face in an entirely different manner, depending on its level of reality. We conducted an experiment using fMRI in order to investigate the effects of emoticons. The results show that right inferior frontal gyrus, which associated with nonverbal communication, is activated by emoticons. Since the emoticons were created to reflect the real human facial expressions as accurately as possible, we believed that they would activate the right fusiform gyrus. However, this region was not found to be activated during the experiment. This finding is useful in understanding how abstract faces affect our behaviors and decision-making in communication over a computer network.

  9. The corticospinal tract in amyotrophic lateral sclerosis: an MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, E.; Warmuth-Metz, M. [Department of Neuroradiology, University of Wuerzburg (Germany); Ochs, G.; Pelzl, A. [Department of Neurology, University of Wuerzburg, Wuerzburg (Germany)

    1998-02-01

    Cortical motor neurone loss and corticospinal tract (CST) degeneration are typical of amyotrophic lateral sclerosis (ALS). It is a matter of debate whether qualitative assessment of the CST by MRI is useful in the diagnosis. It is also an open question whether quantitative determination of the T2 relaxation times can improve its value. Signal intensity along the CST on 14 consecutive slices was assessed using arbitrary visual rating on double-echo T2-weighted and proton-density spin-echo images of 21 patients with ALS and 21 age- and sex-matched controls. T2 was determined quantitatively. On the T2-weighted images the patients` ratings did not differ from that of controls. The T2 of patients and controls showed no statistical difference in any slice. There was no correlation between T2 and patient age, duration of the disease, or predominant bulbar, lower or upper motor neurone signs. The only correlation between MRI findings and disease was on the proton-density images: all cases in which the CST was poorly seen were controls; a clearly high-signal CST was seen only in the patients. High conspicuity of the CST was thus specific but not sensitive for the diagnosis of ALS. T2-weighted images and measurement of T2 were not useful for diagnosis. (orig.) With 2 figs., 1 tab., 26 refs.

  10. Laminectomy-induced arachnoradiculitis: a postoperative serial MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, H [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Tsuji, H [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Kanamori, M [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Kawaguchi, Y [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Yudoh, K [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Futatsuya, R [Departments of Radiology, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan)

    1995-11-01

    Time-related changes of laminectomy-induced cauda equina adhesions were investigated by MRI in ten patients with degenerative spinal disease who underwent posterior surgery to the lumbar spine; seven had disc herniations and three spinal stenosis. Axial MRI was performed before and 3, 7, 21 and 42 days after surgery. Cauda equina adhesions were most severe at the laminectomised levels L3-4, L4-5 and L5-S1 (n = 16); partial adhesions were found in 9 of 16 levels at 6 weeks after surgery. At the L3-4 or L5-S1 levels (n = 14), the area of laminar exposure without laminectomy, the cauda equina adhesions continued 1 week after surgery, but thereafter resolved; only partial adhesions were seen at 5 of 14 levels 6 weeks after surgery. Shrinkage of the arachnoid sac was also found at the level of the laminectomy, but it re-expanded 3 weeks after surgery in all cases. Cauda equina adhesions and shrinkage of the sac were correlated closely with laminectomy, with or without discectomy, suggesting that an inflammatory process of deep wound healing may be involved in the mechanism of a laminectomy-induced arachnoradiculitis which may be correlated with postoperative leg symptoms. (orig.). With 7 figs., 1 tab.

  11. Laminectomy-induced arachnoradiculitis: a postoperative serial MRI study

    International Nuclear Information System (INIS)

    Matsui, H.; Tsuji, H.; Kanamori, M.; Kawaguchi, Y.; Yudoh, K.; Futatsuya, R.

    1995-01-01

    Time-related changes of laminectomy-induced cauda equina adhesions were investigated by MRI in ten patients with degenerative spinal disease who underwent posterior surgery to the lumbar spine; seven had disc herniations and three spinal stenosis. Axial MRI was performed before and 3, 7, 21 and 42 days after surgery. Cauda equina adhesions were most severe at the laminectomised levels L3-4, L4-5 and L5-S1 (n = 16); partial adhesions were found in 9 of 16 levels at 6 weeks after surgery. At the L3-4 or L5-S1 levels (n = 14), the area of laminar exposure without laminectomy, the cauda equina adhesions continued 1 week after surgery, but thereafter resolved; only partial adhesions were seen at 5 of 14 levels 6 weeks after surgery. Shrinkage of the arachnoid sac was also found at the level of the laminectomy, but it re-expanded 3 weeks after surgery in all cases. Cauda equina adhesions and shrinkage of the sac were correlated closely with laminectomy, with or without discectomy, suggesting that an inflammatory process of deep wound healing may be involved in the mechanism of a laminectomy-induced arachnoradiculitis which may be correlated with postoperative leg symptoms. (orig.). With 7 figs., 1 tab

  12. An experimental study on MRI signal intensity of albumin solution

    International Nuclear Information System (INIS)

    Ahn, In Oak; Chang, Kee Hyun; Han, Moon Hee; Song, Chi Sung; Yeon, Kyung Mo

    1990-01-01

    This in vitro study attempted to correlate magnetic resonance (MR) signal intensity with concentration of albumin solution in magnetic field strength of 2.0 Tesla (T) and 0.5T. MR imaging of bovine serum albumin solutions of various concentrations ranging from 0 to 40 g/dl was performed on both 2.0T and 0.5T MR units. The relative (with respect to normal saline) signal intensities of each albumin solution were measured in T1-weighted, proton density-weighted and T2-weighted MR images, correlated with albumin concentration on each pulse sequence, and compared between 2.0T and 0.5T. Additionally, the albumin concentrations showing signal intensities identical to those of white matter, cortical gray matter and cerebrospinal fluid (CSF) of normal brain MRI were determined by visual comparison of those images. 1. On T1-weighted (SE 400-500 msec/30 msec) images under 2.0T and 0.5T field strength, the signal intensity increased with increasing albumin concentrations up to about 30-35 g/dl and the decreased. For the solutions ranging from 0 to about 5 g/dl concentration, the signal intensities appeared isointense to normal saline on visual inspection. 2. On proton density-weighted (SE 2000-2500 msec/30 msec) images under 2.0T and 0.5T field strength, the signal intensity slightly increased with increasing albumin concentrations up to about 7.5-10 g/dl, and then gradually decreased. 3. On T2-weighted (SE 2000-2500 msec/80-100 msec) images under 2.0T and 0.5T field strength, the signal intensity slightly increased with increasing albumin concentrations up to about 7.5-10 g/dl, and then gradually decreased. Above the concentration of about 25-30 g/dl, the signal intensity appeared lower than that of normal saline on visual inspection. 4. Compared with the signal intensities of normal brain structures on T1-weighted images under 2.0T and 0.5T field strength, the signal intensities of the albumin solution below 2.5-5 g/dl concentration were similar to that of CSF, and those of

  13. Processing and regulation of negative emotions in anorexia nervosa: An fMRI study

    Directory of Open Access Journals (Sweden)

    Maria Seidel

    Full Text Available Theoretical models and recent advances in the treatment of anorexia nervosa (AN have increasingly focused on the role of alterations in the processing and regulation of emotions. To date, however, our understanding of these changes is still limited and reports of emotional dysregulation in AN have been based largely on self-report data, and there is a relative lack of objective experimental evidence or neurobiological data.The current functional magnetic resonance imaging (fMRI study investigated the hemodynamic correlates of passive viewing and voluntary downregulation of negative emotions by means of the reappraisal strategy detachment in AN patients. Detachment is regarded as adaptive regulation strategy associated with a reduction in emotion-related amygdala activity and increased recruitment of prefrontal brain regions associated with cognitive control processes. Emotion regulation efficacy was assessed via behavioral arousal ratings and fMRI activation elicited by an established experimental paradigm including negative images. Participants were instructed to either simply view emotional pictures or detach themselves from feelings triggered by the stimuli.The sample consisted of 36 predominantly adolescent female AN patients and a pairwise age-matched healthy control group. Behavioral and neuroimaging data analyses indicated a reduction of arousal and amygdala activity during the regulation condition for both patients and controls. However, compared with controls, individuals with AN showed increased activation in the amygdala as well as in the right dorsolateral prefrontal cortex (dlPFC during the passive viewing of aversive compared with neutral pictures.These results extend previous findings indicative of altered processing of salient emotional stimuli in AN, but do not point to a general deficit in the voluntary regulation of negative emotions. Increased dlPFC activation in AN during passive viewing of negative stimuli is in line with

  14. Categorical speech processing in Broca's area: an fMRI study using multivariate pattern-based analysis.

    Science.gov (United States)

    Lee, Yune-Sang; Turkeltaub, Peter; Granger, Richard; Raizada, Rajeev D S

    2012-03-14

    Although much effort has been directed toward understanding the neural basis of speech processing, the neural processes involved in the categorical perception of speech have been relatively less studied, and many questions remain open. In this functional magnetic resonance imaging (fMRI) study, we probed the cortical regions mediating categorical speech perception using an advanced brain-mapping technique, whole-brain multivariate pattern-based analysis (MVPA). Normal healthy human subjects (native English speakers) were scanned while they listened to 10 consonant-vowel syllables along the /ba/-/da/ continuum. Outside of the scanner, individuals' own category boundaries were measured to divide the fMRI data into /ba/ and /da/ conditions per subject. The whole-brain MVPA revealed that Broca's area and the left pre-supplementary motor area evoked distinct neural activity patterns between the two perceptual categories (/ba/ vs /da/). Broca's area was also found when the same analysis was applied to another dataset (Raizada and Poldrack, 2007), which previously yielded the supramarginal gyrus using a univariate adaptation-fMRI paradigm. The consistent MVPA findings from two independent datasets strongly indicate that Broca's area participates in categorical speech perception, with a possible role of translating speech signals into articulatory codes. The difference in results between univariate and multivariate pattern-based analyses of the same data suggest that processes in different cortical areas along the dorsal speech perception stream are distributed on different spatial scales.

  15. Contribution of macrophages in the contrast loss in iron oxide-based MRI cancer cell tracking studies

    Science.gov (United States)

    Danhier, Pierre; Deumer, Gladys; Joudiou, Nicolas; Bouzin, Caroline; Levêque, Philippe; Haufroid, Vincent; Jordan, Bénédicte F.; Feron, Olivier; Sonveaux, Pierre; Gallez, Bernard

    2017-01-01

    Magnetic resonance imaging (MRI) cell tracking of cancer cells labeled with superparamagnetic iron oxides (SPIO) allows visualizing metastatic cells in preclinical models. However, previous works showed that the signal void induced by SPIO on T2(*)-weighted images decreased over time. Here, we aim at characterizing the fate of iron oxide nanoparticles used in cell tracking studies and the role of macrophages in SPIO metabolism. In vivo MRI cell tracking of SPIO positive 4T1 breast cancer cells revealed a quick loss of T2* contrast after injection. We next took advantage of electron paramagnetic resonance (EPR) spectroscopy and inductively coupled plasma mass spectroscopy (ICP-MS) for characterizing the evolution of superparamagnetic and non-superparamagnetic iron pools in 4T1 breast cancer cells and J774 macrophages after SPIO labeling. These in vitro experiments and histology studies performed on 4T1 tumors highlighted the quick degradation of iron oxides by macrophages in SPIO-based cell tracking experiments. In conclusion, the release of SPIO by dying cancer cells and the subsequent uptake of iron oxides by tumor macrophages are limiting factors in MRI cell tracking experiments that plead for the use of (MR) reporter-gene based imaging methods for the long-term tracking of metastatic cells. PMID:28467814

  16. Estimating the effect of current, previous and never use of drugs in studies based on prescription registries

    DEFF Research Database (Denmark)

    Nielsen, Lars Hougaard; Løkkegaard, Ellen; Andreasen, Anne Helms

    2009-01-01

    of this misclassification for analysing the risk of breast cancer. MATERIALS AND METHODS: Prescription data were obtained from Danish Registry of Medicinal Products Statistics and we applied various methods to approximate treatment episodes. We analysed the duration of HT episodes to study the ability to identify......PURPOSE: Many studies which investigate the effect of drugs categorize the exposure variable into never, current, and previous use of the study drug. When prescription registries are used to make this categorization, the exposure variable possibly gets misclassified since the registries do...... not carry any information on the time of discontinuation of treatment.In this study, we investigated the amount of misclassification of exposure (never, current, previous use) to hormone therapy (HT) when the exposure variable was based on prescription data. Furthermore, we evaluated the significance...

  17. Accelerating volumetric cine MRI (VC-MRI) using undersampling for real-time 3D target localization/tracking in radiation therapy: a feasibility study

    Science.gov (United States)

    Harris, Wendy; Yin, Fang-Fang; Wang, Chunhao; Zhang, You; Cai, Jing; Ren, Lei

    2018-01-01

    Purpose. To accelerate volumetric cine MRI (VC-MRI) using undersampled 2D-cine MRI to provide real-time 3D guidance for gating/target tracking in radiotherapy. Methods. 4D-MRI is acquired during patient simulation. One phase of the prior 4D-MRI is selected as the prior images, designated as MRIprior. The on-board VC-MRI at each time-step is considered a deformation of the MRIprior. The deformation field map is represented as a linear combination of the motion components extracted by principal component analysis from the prior 4D-MRI. The weighting coefficients of the motion components are solved by matching the corresponding 2D-slice of the VC-MRI with the on-board undersampled 2D-cine MRI acquired. Undersampled Cartesian and radial k-space acquisition strategies were investigated. The effects of k-space sampling percentage (SP) and distribution, tumor sizes and noise on the VC-MRI estimation were studied. The VC-MRI estimation was evaluated using XCAT simulation of lung cancer patients and data from liver cancer patients. Volume percent difference (VPD) and Center of Mass Shift (COMS) of the tumor volumes and tumor tracking errors were calculated. Results. For XCAT, VPD/COMS were 11.93  ±  2.37%/0.90  ±  0.27 mm and 11.53  ±  1.47%/0.85  ±  0.20 mm among all scenarios with Cartesian sampling (SP  =  10%) and radial sampling (21 spokes, SP  =  5.2%), respectively. When tumor size decreased, higher sampling rate achieved more accurate VC-MRI than lower sampling rate. VC-MRI was robust against noise levels up to SNR  =  20. For patient data, the tumor tracking errors in superior-inferior, anterior-posterior and lateral (LAT) directions were 0.46  ±  0.20 mm, 0.56  ±  0.17 mm and 0.23  ±  0.16 mm, respectively, for Cartesian-based sampling with SP  =  20% and 0.60  ±  0.19 mm, 0.56  ±  0.22 mm and 0.42  ±  0.15 mm, respectively, for

  18. A Retrospective Study Evaluating the Impact of Preoperative Breast MRI on Surgical Decision-Making in Young Patients (≤50 Years with Invasive Breast Cancer

    Directory of Open Access Journals (Sweden)

    Som D. Mukherjee

    2016-01-01

    Full Text Available Introduction Breast magnetic resonance imaging (MRI is considered a more sensitive diagnostic test for detecting invasive breast cancer than mammography or breast ultrasound. Breast MRI may be particularly useful in younger premenopausal women with higher density breast tissue for differentiating between dense fibroglandular breast tissue and breast malignancies. The main objective of this study was to determine the impact of preoperative breast MRI on surgical decision-making in young women with breast cancer. Methods A retrospective review of patients with newly diagnosed invasive breast cancer and age of ≤50 years was performed. All patients underwent physical examination, preoperative mammogram, breast ultrasound, and bilateral breast MRI. Two breast cancer surgeons reviewed the preoperative mammogram report, breast ultrasound report, and physical examination summary and were asked if they would recommend a lumpectomy, a quandrantectomy, or a mastectomy. A few weeks later, the two surgeons were shown the same information with the breast MRI report and were asked what type of surgery they would now recommend. In each case, MRI was classified by two adjudicators as having affected the surgical outcome in a positive, negative, or neutral fashion. A positive impact was defined as the situation where breast MRI detected additional disease that was not found on physical examination, mammogram, or breast ultrasound and led to an appropriate change in surgical management. A negative impact was defined as the situation where breast MRI led the surgeon to recommend more extensive surgery, with less extensive disease actually found at pathology. No impact was defined as the situation where MRI findings did not alter surgical recommendations or outcomes. Results Of 37 patients whose charts were reviewed, five patients were deemed to be ineligible due to having received neoadjuvant chemotherapy, having previous breast implants, or having had their

  19. Evidence for Policy Making: Clinical Appropriateness Study of Lumbar Spine MRI Prescriptions Using RAND Appropriateness Method

    Directory of Open Access Journals (Sweden)

    Hossein Yousefi Manesh

    2013-01-01

    Full Text Available MRI is a new and expensive diagnostic technology, which has been used increasingly all over the world. Low back pain is a worldwide prevalent disorder and MRI technique is one of the several ways to diagnose it. This paper aims to identify the appropriateness of lumbar spine MRI prescriptions in Shiraz teaching hospitals using standardized RAND Appropriateness Method (RAM criteria. Methods This study consisted of two phases. The first phase involved a qualitative enquiry and the second phase had a quantitative cross-sectional nature. In the first phase RAM was used for developing lumbar spine MRI indications and scenarios. In the second phase, the finalized scenarios were compared with the history and physical examination of 300 patients with low back pain. The rate of appropriateness of lumbar spine MRI prescription was then calculated. Results Of 300 cases of lumbar spine MRI prescriptions, approximately 167 (56% were considered inappropriate, 72 (24% were uncertain, and 61 (20% were deemed to be appropriate. The economic burden of inappropriate prescriptions was calculated at 88,009,000 Rials. In addition, the types of expertise and physical examination were considered as related factors to appropriateness of prescriptions. Conclusion In conclusion, a large proportion of lumbar spine MRI prescriptions, which result in financial burden on the insurance companies and the patients alike is unnecessary. This study suggests that policy makers consider this evidence while decision-making. Our findings highlight the imperative role of Health Technology Assessment (HTA and Clinical Practice Guidelines (CPGs. As a result, developing local clinical guidelines may create the commitment needed in physicians in prescribing appropriate prescriptions within the health sector. The study further recommends that appropriate scenarios should be considered as a criterion for payment and reimbursement.

  20. HLA-B27 and gender independently determine the likelihood of a positive MRI of the sacroiliac joints in patients with early inflammatory back pain: a 2-year MRI follow-up study

    NARCIS (Netherlands)

    van Onna, M.; Jurik, A. G.; van der Heijde, D.; van Tubergen, A.; Heuft-Dorenbosch, L.; Landewé, R.

    2011-01-01

    To describe how inflammation on MRI of the sacroiliac joints in patients with recent-onset inflammatory back pain (IBP) evolves over time, and to study determinants of activity on MRI of the sacroiliac joint. A 2-year follow-up study with annual MRI of the sacroiliac joints was conducted in patients

  1. Lactate quantification by proton magnetic resonance spectroscopy using a clinical MRI machine: a basic study

    International Nuclear Information System (INIS)

    Isobe, T.; Muraishi, H.; Matsumura, A.; Kawamura, H.; Shibata, Y.; Anno, I.; Minami, M.

    2007-01-01

    The purpose of this study was to establish quantification method of lactate concentration by proton magnetic resonance spectroscopy (MRS) carried out using a conventional 1.5-T MRI machine. We used a lactate phantom with known concentrations (1, 1.5, 3, 6, 12 and 14 mmol/L). As a clinical example, a patient with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) was evaluated. Proton MRS was carried out using a clinical 1.5-T super-conducting magnetic resonance whole-body system. Data were acquired by point resolved spectroscopy. A coupling constant of J = 7.35 Hz (2/7 = 272 ms) and two long in-phase echo time of 272 ms and 544 ms were used to calculate the T2 relaxation time. The tissue water signal was used as an internal standard to quantify lactate. The correlation coefficient R between the calculated lactate concentrations and the known concentration of lactate was 0.99 with a constant factor of 0.32 (1/3.14). In patients with MELAS, the lactate concentration measured by MRS was 6.2 mmol/kg wet weight, which is similar to the value obtained in previous studies. In the present study, we have established a reliable method for lactate quantification in a phantom study and have shown a sample of clinical case of MELAS

  2. MORPHOMETRIC ANALYSIS OF CORPUS CALLOSUM- A STUDY IN CADAVER AND MRI

    Directory of Open Access Journals (Sweden)

    Ambili Puthanveetil

    2017-07-01

    Full Text Available BACKGROUND The Corpus Callosum (CC can best be seen in the mid-sagittal section of brain both in cadaver and MRI. The morphometric measurements of the same will be of use in neurosurgical procedures. Sexual dimorphism and the age-related changes in its measurements remained controversial. Till date, no studies have been done on corpus callosum in Kerala. MATERIALS AND METHODS Measurements of CC has been taken and studied in detail in 24 formalin fixed brains from the Department of Anatomy and 48 MR images from the Department of Radiology. The changes according to age and sex were analysed. RESULTS The mean length of CC in the cadaver was 7.24 cm, which was 3.38 cm posterior to frontal pole and 5.73 cm anterior to occipital pole. In MR images, the mean length was 7.10 in males and 6.76 in females. The difference we got was not statistically significant. The length increased with age. Thickness of genu and body decreased as the age advances, but the splenial thickness was found to be increasing with age. There was significant correlation between the thicknesses of various parts of CC. CONCLUSION The values were almost similar to those in the previous studies. Morphometrically, a significant gender difference was not identified in the present study. There were changes according to age both in males and females.

  3. MRI Primer

    International Nuclear Information System (INIS)

    Oldendorf, W.; Oldendorf, W. Jr.

    1991-01-01

    Designed for studies, radiologists, and clinicians at all levels of training, this book provides a basic introduction to the principles, physics, and instrumentation of magnetic resonance imaging. The fundamental concepts that are essential for the optimal clinical use of MRI are thoroughly explained in easily accessible terms. To facilitate the reader's comprehension, the material is presented nonmathematically, using no equations and a minimum of symbols and abbreviations. MRI Primer presents a clear account of the phenomenon of nuclear magnetic resonance and the use of gradient magnetic fields to create clinically useful images of cross-sectional slices. Close attention is given to the magnetization vector as a means of expressing nuclear behavior, the role of T 1 and T 2 weighing in imaging, the use of contrast agents, and the pulse sequences most often used in clinical practice, as well as to the relative capabilities and limitations of MRI and CT. The basic hardware components of an MRI scanner are described in detail. Sample MRI scans illustrate how MRI characterizes tissue. An appendix provides a brief introduction to quantum processes in MRI

  4. Renal and perirenal space involvement in acute pancreatitis: An MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xing Hui, E-mail: lixinghui1005@126.com [Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000 (China); Zhang, Xiao Ming, E-mail: cjr.zhxm@vip.163.com [Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000 (China); Ji, Yi Fan, E-mail: 526504036@qq.com [Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000 (China); Jing, Zong Lin, E-mail: jzl325@163.com [Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000 (China); Huang, Xiao Hua, E-mail: nc_hxh1966@yahoo.com.cn [Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000 (China); Yang, Lin, E-mail: linyangmd@163.com [Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000 (China); Zhai, Zhao Hua, E-mail: zhaizhaohuada@163.com [Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000 (China)

    2012-08-15

    Objectives: To study the prevalence and characteristics of renal and perirenal space involvement and its relation to the severity of acute pancreatitis (AP) using MRI. Methods: 115 patients with AP who underwent MRI with the clinical kidney function test were retrospectively analyzed in this study. MRI sequences included conventional and diffusion weighted imaging (DWI) sequences. The renal and perirenal space involvement in AP was noted on MRI. The renal apparent diffusion coefficient (ADC) on DWI was measured for each kidney. The severity of AP on MRI was graded using MR severity index (MRSI). The relationships among the renal and perirenal space involvement on MRI, the renal ADC, MRSI and the results of the kidney function test were analyzed. Results: In the 115 patients with AP, the renal and perirenal space abnormalities detected included renal parenchymal abnormalities (0.8%), abnormalities of the renal collecting system (2.6%), renal vascular abnormalities (1.7%), thickened renal fascia (99%), perirenal stranding (62%) and perirenal fluid collection (40%). The prevalence of perirenal space abnormalities was correlated with the severity of AP based on MRSI (P < 0.05). The renal ADC values were lower in patients with abnormal kidney function than in those without kidney injury (P < 0.05). The prevalence of kidney function abnormalities was 9.4%, 32% and 100% in mild, moderate, and severe AP cases, respectively (P = 0.00). Conclusion: Perirenal space involvement is much more than renal parenchymal involvement in AP. The prevalence of perirenal space involvement in AP on MRI has a positive correlation with the severity of AP according to MRSI.

  5. Renal and perirenal space involvement in acute pancreatitis: An MRI study

    International Nuclear Information System (INIS)

    Li, Xing Hui; Zhang, Xiao Ming; Ji, Yi Fan; Jing, Zong Lin; Huang, Xiao Hua; Yang, Lin; Zhai, Zhao Hua

    2012-01-01

    Objectives: To study the prevalence and characteristics of renal and perirenal space involvement and its relation to the severity of acute pancreatitis (AP) using MRI. Methods: 115 patients with AP who underwent MRI with the clinical kidney function test were retrospectively analyzed in this study. MRI sequences included conventional and diffusion weighted imaging (DWI) sequences. The renal and perirenal space involvement in AP was noted on MRI. The renal apparent diffusion coefficient (ADC) on DWI was measured for each kidney. The severity of AP on MRI was graded using MR severity index (MRSI). The relationships among the renal and perirenal space involvement on MRI, the renal ADC, MRSI and the results of the kidney function test were analyzed. Results: In the 115 patients with AP, the renal and perirenal space abnormalities detected included renal parenchymal abnormalities (0.8%), abnormalities of the renal collecting system (2.6%), renal vascular abnormalities (1.7%), thickened renal fascia (99%), perirenal stranding (62%) and perirenal fluid collection (40%). The prevalence of perirenal space abnormalities was correlated with the severity of AP based on MRSI (P < 0.05). The renal ADC values were lower in patients with abnormal kidney function than in those without kidney injury (P < 0.05). The prevalence of kidney function abnormalities was 9.4%, 32% and 100% in mild, moderate, and severe AP cases, respectively (P = 0.00). Conclusion: Perirenal space involvement is much more than renal parenchymal involvement in AP. The prevalence of perirenal space involvement in AP on MRI has a positive correlation with the severity of AP according to MRSI.

  6. Differentiation of periapical granulomas and cysts by using dental MRI: a pilot study.

    Science.gov (United States)

    Juerchott, Alexander; Pfefferle, Thorsten; Flechtenmacher, Christa; Mente, Johannes; Bendszus, Martin; Heiland, Sabine; Hilgenfeld, Tim

    2018-05-17

    The purpose of this pilot study was to evaluate whether periapical granulomas can be differentiated from periapical cysts in vivo by using dental magnetic resonance imaging (MRI). Prior to apicoectomy, 11 patients with radiographically confirmed periapical lesions underwent dental MRI, including fat-saturated T2-weighted (T2wFS) images, non-contrast-enhanced T1-weighted images with and without fat saturation (T1w/T1wFS), and contrast-enhanced fat-saturated T1-weighted (T1wFS+C) images. Two independent observers performed structured image analysis of MRI datasets twice. A total of 15 diagnostic MRI criteria were evaluated, and histopathological results (6 granulomas and 5 cysts) were compared with MRI characteristics. Statistical analysis was performed using intraclass correlation coefficient (ICC), Cohen's kappa (κ), Mann-Whitney U-test and Fisher's exact test. Lesion identification and consecutive structured image analysis was possible on T2wFS and T1wFS+C MRI images. A high reproducibility was shown for MRI measurements of the maximum lesion diameter (intraobserver ICC = 0.996/0.998; interobserver ICC = 0.997), for the "peripheral rim" thickness (intraobserver ICC = 0.988/0.984; interobserver ICC = 0.970), and for all non-quantitative MRI criteria (intraobserver-κ = 0.990/0.995; interobserver-κ = 0.988). In accordance with histopathological results, six MRI criteria allowed for a clear differentiation between cysts and granulomas: (1) outer margin of lesion, (2) texture of "peripheral rim" in T1wFS+C, (3) texture of "lesion center" in T2wFS, (4) surrounding tissue involvement in T2wFS, (5) surrounding tissue involvement in T1wFS+C and (6) maximum "peripheral rim" thickness (all: P periapical cysts and granulomas in vivo. Thus, MRI may substantially improve treatment strategies and help to avoid unnecessary surgery in apical periodontitis.

  7. In vivo longitudinal MRI and behavioral studies in experimental spinal cord injury.

    Science.gov (United States)

    Sundberg, Laura M; Herrera, Juan J; Narayana, Ponnada A

    2010-10-01

    Comprehensive in vivo longitudinal studies that include multi-modal magnetic resonance imaging (MRI) and a battery of behavioral assays to assess functional outcome were performed at multiple time points up to 56 days post-traumatic spinal cord injury (SCI) in rodents. The MRI studies included high-resolution structural imaging for lesion volumetry, and diffusion tensor imaging (DTI) for probing the white matter integrity. The behavioral assays included open-field locomotion, grid walking, inclined plane, computerized activity box performance, and von Frey filament tests. Additionally, end-point histology was assessed for correlation with both the MRI and behavioral data. The temporal patterns of the lesions were documented on structural MRI. DTI studies showed significant changes in white matter that is proximal to the injury epicenter and persisted to day 56. White matter in regions up to 1 cm away from the injury epicenter that appeared normal on conventional MRI also exhibited changes that were indicative of tissue damage, suggesting that DTI is a more sensitive measure of the evolving injury. Correlations between DTI and histology after SCI could not be firmly established, suggesting that injury causes complex pathological changes in multiple tissue components that affect the DTI measures. Histological evidence confirmed a significant decrease in myelin and oligodendrocyte presence 56 days post-SCI. Multiple assays to evaluate aspects of functional recovery correlated with histology and DTI measures, suggesting that damage to specific white matter tracts can be assessed and tracked longitudinally after SCI.

  8. MRI outcomes with cladribine tablets for multiple sclerosis in the CLARITY study.

    Science.gov (United States)

    Comi, Giancarlo; Cook, Stuart D; Giovannoni, Gavin; Rammohan, Kottil; Rieckmann, Peter; Sørensen, Per Soelberg; Vermersch, Patrick; Hamlett, Anthony C; Viglietta, Vissia; Greenberg, Steven J

    2013-04-01

    We herein provide a comprehensive assessment of magnetic resonance imaging (MRI) outcomes from CLARITY, a 96-week, double-blind study demonstrating significant clinical and MRI improvements in patients with relapsing-remitting multiple sclerosis (RRMS) treated with cladribine tablets. Patients with RRMS were randomized 1:1:1 to annual short-course therapy with cladribine tablets cumulative dose 3.5 or 5.25 mg/kg or placebo. MRI endpoints included mean number of T1 gadolinium-enhancing (Gd+), active T2 and combined unique (CU) lesions/patient/scan. MRI-measured disease activity was significantly reduced in both cladribine tablets groups versus placebo. The proportion of patients with no active lesions at study end was: T1 Gd+ lesions: 86.8 and 91.0 versus 48.3 % (p tablet groups when data were stratified by baseline disease characteristics. For example, the percentage of patients who remained lesion-free over the study was significantly greater in cladribine tablet groups than in the placebo group for all lesion types regardless of relapse category at baseline (p MRI-measured disease activity was greatly reduced by both doses of cladribine tablets, with consistent effect across clinically relevant patient populations. These findings add to our scientific understanding of the neurological impact of this therapeutic modality in patients with RRMS.

  9. Neutral lipid storage disease with myopathy: A whole-body nuclear MRI and metabolic study

    International Nuclear Information System (INIS)

    Laforet, Pascal; Stojkovic, Tanya; Wahbi, Karim; Eymard, Bruno; Bassez, Guillaume; Carlier, Pierre G.; Clement, Karine; Petit, Francois M.; Carlier, Robert-Yves

    2013-01-01

    Neutral lipid storage disease with myopathy (NLSDM) is caused by a mutation in the gene encoding adipose triglyceride lipase (ATGL), and is characterized by the presence of numerous triglyceride-containing cytoplasmic droplets in type I muscle fibers. Major clinical manifestations concern the heart and skeletal muscle, and some patients also present diabetes mellitus. We report the clinical, metabolic, and whole-body nuclear magnetic resonance imaging findings of three patients with NLSDM. Muscle MRI study was consistent with previous descriptions, and allowed to show a common pattern of fatty replacement. Muscle changes predominated in the paravertebral muscles, both compartments of legs, and posterior compartment of the thighs. A more variable distribution of muscle involvement was observed on upper limbs, with marked asymmetry in one patient, and alterations predominating on supra and infra spinatus, biceps brachialis and anterior compartment of arms. Cardiac NMR studies revealed anomalies despite normal echocardiography in two patients. Endocrine studies showed low leptin and adiponectine levels, a moderate increase in insulin levels at fasting state, and even greater increase after oral glucose tolerance test in one patient. Two patients had elevated triglycerides and low cholesterol-HDL. Based on these analyses, regular control of cardio-metabolic risks appear mandatory in the clinical follow-up of these subjects. (authors)

  10. Emotional Picture and Word Processing: An fMRI Study on Effects of Stimulus Complexity

    Science.gov (United States)

    Schlochtermeier, Lorna H.; Kuchinke, Lars; Pehrs, Corinna; Urton, Karolina; Kappelhoff, Hermann; Jacobs, Arthur M.

    2013-01-01

    Neuroscientific investigations regarding aspects of emotional experiences usually focus on one stimulus modality (e.g., pictorial or verbal). Similarities and differences in the processing between the different modalities have rarely been studied directly. The comparison of verbal and pictorial emotional stimuli often reveals a processing advantage of emotional pictures in terms of larger or more pronounced emotion effects evoked by pictorial stimuli. In this study, we examined whether this picture advantage refers to general processing differences or whether it might partly be attributed to differences in visual complexity between pictures and words. We first developed a new stimulus database comprising valence and arousal ratings for more than 200 concrete objects representable in different modalities including different levels of complexity: words, phrases, pictograms, and photographs. Using fMRI we then studied the neural correlates of the processing of these emotional stimuli in a valence judgment task, in which the stimulus material was controlled for differences in emotional arousal. No superiority for the pictorial stimuli was found in terms of emotional information processing with differences between modalities being revealed mainly in perceptual processing regions. While visual complexity might partly account for previously found differences in emotional stimulus processing, the main existing processing differences are probably due to enhanced processing in modality specific perceptual regions. We would suggest that both pictures and words elicit emotional responses with no general superiority for either stimulus modality, while emotional responses to pictures are modulated by perceptual stimulus features, such as picture complexity. PMID:23409009

  11. Neutral lipid storage disease with myopathy: A whole-body nuclear MRI and metabolic study

    Energy Technology Data Exchange (ETDEWEB)

    Laforet, Pascal; Stojkovic, Tanya; Wahbi, Karim; Eymard, Bruno [AP-HP, Centre de Reference de pathologie neuromusculaire Paris-Est, Groupe Hospitalier Pitie-Salpetriere, Assistance Publique-Hopitaux de Paris, Paris, (France); Bassez, Guillaume [AP-HP, Centre de Reference de Pathologie Neuromusculaire Paris-Ouest, CHU Henri Mondor, Creteil, (France); Carlier, Pierre G. [CEA, I2BM, MIRCen, IdM NMR Laboratory, T-75651 Paris, (France); Clement, Karine [AP-HP, Institute of Cardiometabolism and Nutrition, ICAN, Pitie-Salpetriere Hospital, University Pierre et Marie-Curie Paris6, Paris, INSERM, U872 team 7, Paris, (France); Petit, Francois M. [AP-HP, Molecular Genetics and Metabolic Diseases Laboratory, Antoine Beclere Hospital, Clamart, (France); Carlier, Robert-Yves [AP-HP, Departement d' imagerie Medicale et Centre d' innovation Technologique, CHU Raymond-Poincare, Garches, (France)

    2013-07-01

    Neutral lipid storage disease with myopathy (NLSDM) is caused by a mutation in the gene encoding adipose triglyceride lipase (ATGL), and is characterized by the presence of numerous triglyceride-containing cytoplasmic droplets in type I muscle fibers. Major clinical manifestations concern the heart and skeletal muscle, and some patients also present diabetes mellitus. We report the clinical, metabolic, and whole-body nuclear magnetic resonance imaging findings of three patients with NLSDM. Muscle MRI study was consistent with previous descriptions, and allowed to show a common pattern of fatty replacement. Muscle changes predominated in the paravertebral muscles, both compartments of legs, and posterior compartment of the thighs. A more variable distribution of muscle involvement was observed on upper limbs, with marked asymmetry in one patient, and alterations predominating on supra and infra spinatus, biceps brachialis and anterior compartment of arms. Cardiac NMR studies revealed anomalies despite normal echocardiography in two patients. Endocrine studies showed low leptin and adiponectine levels, a moderate increase in insulin levels at fasting state, and even greater increase after oral glucose tolerance test in one patient. Two patients had elevated triglycerides and low cholesterol-HDL. Based on these analyses, regular control of cardio-metabolic risks appear mandatory in the clinical follow-up of these subjects. (authors)

  12. Clinical significance of reduced cerebral metabolism in multiple sclerosis. A combined PET and MRI study

    International Nuclear Information System (INIS)

    Sun, Xiayan; Tanaka, Makoto; Kondo, Susumu; Okamoto, Koichi; Hirai, Shunsaku

    1998-01-01

    Magnetic resonance imaging (MRI) in patients with multiple sclerosis (MS) has provided major insights into the disease's natural history, and many studies have focussed on possible correlations between MRI findings and the clinical manifestations of MS. In contrast, there are few reports on possible relationships between functional imaging data and cognitive function. The present study assessed the relationship between clinical presentation and combined anatomical and functional imaging data in MS. Twenty patients with definite MS underwent MRI and positron emission tomography (PET) to evaluate cerebral blood flow (rCBF) and oxygen metabolism (rCMRO 2 ). The relationships between these neuroimaging findings and clinical data, including the Expanded Disability Status Scale (EDSS), Mini-mental status scale, Hasegawa Dementia Scale and relapse time, were evaluated with Spearman's rank correlation coefficients. A general reduction in rCBF and rCMRO 2 in the gray and white matter were found in the MS patients. EDSS was correlated with the number and size of the lesions on MRI and was negatively correlated with rCMRO 2 . A correlation between the decrease in rCMRO 2 and the level of cognitive impairment was also found. The severity of cerebral hypometabolism was also related to the number of relapses. Morphological and functional findings obtained by MRI and PET are closely related to the clinical status in MS. Our results suggest that measurement of cerebral metabolism in MS has the potential to be an objective marker for monitoring disease activity and to provide prognostic information. (author)

  13. Early functional MRI activation predicts motor outcome after ischemic stroke: a longitudinal, multimodal study.

    Science.gov (United States)

    Du, Juan; Yang, Fang; Zhang, Zhiqiang; Hu, Jingze; Xu, Qiang; Hu, Jianping; Zeng, Fanyong; Lu, Guangming; Liu, Xinfeng

    2018-05-15

    An accurate prediction of long term outcome after stroke is urgently required to provide early individualized neurorehabilitation. This study aimed to examine the added value of early neuroimaging measures and identify the best approaches for predicting motor outcome after stroke. This prospective study involved 34 first-ever ischemic stroke patients (time since stroke: 1-14 days) with upper limb impairment. All patients underwent baseline multimodal assessments that included clinical (age, motor impairment), neurophysiological (motor-evoked potentials, MEP) and neuroimaging (diffusion tensor imaging and motor task-based fMRI) measures, and also underwent reassessment 3 months after stroke. Bivariate analysis and multivariate linear regression models were used to predict the motor scores (Fugl-Meyer assessment, FMA) at 3 months post-stroke. With bivariate analysis, better motor outcome significantly correlated with (1) less initial motor impairment and disability, (2) less corticospinal tract injury, (3) the initial presence of MEPs, (4) stronger baseline motor fMRI activations. In multivariate analysis, incorporating neuroimaging data improved the predictive accuracy relative to only clinical and neurophysiological assessments. Baseline fMRI activation in SMA was an independent predictor of motor outcome after stroke. A multimodal model incorporating fMRI and clinical measures best predicted the motor outcome following stroke. fMRI measures obtained early after stroke provided independent prediction of long-term motor outcome.

  14. Health complaints among nurses working near MRI scanners-A descriptive pilot study

    International Nuclear Information System (INIS)

    Wilen, Jonna; Vocht, Frank de

    2011-01-01

    A questionnaire-based descriptive pilot study was conducted among all nurses routinely working with MRI in the Northern part of Sweden to provide an indication of the self-reported prevalence of health complaints related to working with MRI systems. Fifty-nine nurses (88% response rate), with on average 8 (±6) years experience with MRI scanning procedures, returned the questionnaire. In total, 9 nurses (15%) reported regularly experiencing at least one of the health complaints (1-5% for specific health complaints) attributed to arise or be aggravated by their presence in the MRI scanning room. Stratification of the results indicated that reporting of adverse symptoms was not related to the level of occupational workload/stress. However, reporting of health complaints was related to the strength of the magnet(s) the nurses worked with, with 57% of symptoms reported by those nurses working with the strongest systems (both 1.5 and 3 T scanners in this population). Although this descriptive study did not include a control population and was based on self-reporting of health complaints, these data indicate that the prevalence of reported health complaints is not related to perceived work load or occupational stress, but does confirm data from other occupational sectors and indicates that the prevalence of adverse health complaints increases with the strength of the MRI system for nurses as well.

  15. Topologic analysis and comparison of brain activation in children with epilepsy versus controls: an fMRI study

    Science.gov (United States)

    Oweis, Khalid J.; Berl, Madison M.; Gaillard, William D.; Duke, Elizabeth S.; Blackstone, Kaitlin; Loew, Murray H.; Zara, Jason M.

    2010-03-01

    This paper describes the development of novel computer-aided analysis algorithms to identify the language activation patterns at a certain Region of Interest (ROI) in Functional Magnetic Resonance Imaging (fMRI). Previous analysis techniques have been used to compare typical and pathologic activation patterns in fMRI images resulting from identical tasks but none of them analyzed activation topographically in a quantitative manner. This paper presents new analysis techniques and algorithms capable of identifying a pattern of language activation associated with localization related epilepsy. fMRI images of 64 healthy individuals and 31 patients with localization related epilepsy have been studied and analyzed on an ROI basis. All subjects are right handed with normal MRI scans and have been classified into three age groups (4-6, 7-9, 10-12 years). Our initial efforts have focused on investigating activation in the Left Inferior Frontal Gyrus (LIFG). A number of volumetric features have been extracted from the data. The LIFG has been cut into slices and the activation has been investigated topographically on a slice by slice basis. Overall, a total of 809 features have been extracted, and correlation analysis was applied to eliminate highly correlated features. Principal Component analysis was then applied to account only for major components in the data and One-Way Analysis of Variance (ANOVA) has been applied to test for significantly different features between normal and patient groups. Twenty Nine features have were found to be significantly different (p<0.05) between patient and control groups

  16. Neurovascular bundle–sparing radiotherapy for prostate cancer using MRI-CT registration: A dosimetric feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Cassidy, R.J., E-mail: richardjcassidy@emory.edu [Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA (United States); Yang, X.; Liu, T.; Thomas, M. [Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA (United States); Nour, S.G. [Department of Radiology, Emory University, Atlanta, GA (United States); Jani, A.B. [Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA (United States)

    2016-01-01

    Purpose: Sexual dysfunction after radiotherapy for prostate cancer remains an important late adverse toxicity. The neurovascular bundles (NVB) that lie posterolaterally to the prostate are typically spared during prostatectomy, but in traditional radiotherapy planning they are not contoured as an organ-at-risk with dose constraints. Our goal was to determine the dosimetric feasibility of “NVB-sparing” prostate radiotherapy while still delivering adequate dose to the prostate. Methods: Twenty-five consecutive patients with prostate cancer (with no extraprostatic disease on pelvic magnetic resonance imaging [MRI]) who that were treated with external beam radiotherapy, with the same primary planning target volume margins, to a dose of 79.2 Gy were evaluated. Pelvic MRI and simulation computed tomography scans were registered using dedicated software to allow for bilateral NVB target delineation on T2-weighted MRI. A volumetric modulated arc therapy plan was generated using the NVB bilaterally with 2 mm margin as an organ to spare and compared to the patient’s previously delivered plan. Dose-volume histogram endpoints for NVB, rectum, bladder, and planning target volume 79.2 were compared between the 2 plans using a 2-tailed paired t-test. Results: The V70 for the NVB was significantly lower on the NVB-sparing plan (p <0.01), while rectum and bladder endpoints were similar. Target V100% was similar but V{sub 105%} was higher for the NVB-sparing plans (p <0.01). Conclusions: “NVB-sparing” radiotherapy is dosimetrically feasible using CT-MRI registration, and for volumetric modulated arc therapy technology — target coverage is acceptable without increased dose to other normal structures, but with higher target dose inhomogeneity. The clinical impact of “NVB-sparing” radiotherapy is currently under study at our institution.

  17. Retrieval orientation and the control of recollection: an fMRI study

    Science.gov (United States)

    Morcom, Alexa M.; Rugg, Michael D.

    2012-01-01

    The present study used event-related fMRI to examine the impact of the adoption of different retrieval orientations on the neural correlates of recollection. In each of two study-test blocks, subjects encoded a mixed list of words and pictures, and then performed a recognition memory task with words as the test items. In one block, the requirement was to respond positively to test items corresponding to studied words, and to reject both new items and items corresponding to the studied pictures. In the other block, positive responses were made to test items corresponding to pictures, and items corresponding to words were classified along with the new items. Based on previous event-related potential (ERP) findings, we predicted that in the word task, recollection-related effects would be found for target information only. This prediction was fulfilled. In both tasks, targets elicited the characteristic pattern of recollection-related activity. By contrast, non-targets elicited this pattern in the picture task, but not in the word task. Importantly, the left angular gyrus was among the regions demonstrating this dissociation of non-target recollection effects according to retrieval orientation. The findings for the angular gyrus parallel prior findings for the `left-parietal' ERP old/new effect, and add to the evidence that the effect reflects recollection-related neural activity originating in left ventral parietal cortex. Thus, the results converge with the previous ERP findings to suggest that the processing of retrieval cues can be constrained to prevent the retrieval of goal-irrelevant information. PMID:23110678

  18. Study of acupuncture point Liv 3 with functional MRI

    International Nuclear Information System (INIS)

    Wang Wei; Li Kuncheng; Hao Jing; Yang Yanhui; Shan Baoci; Yan Bin; Li Ke; Xu Jianyang

    2006-01-01

    Objective: To investigate the mechanism of acupuncture point Liv3 (Taichong) and possible post-effect of acupuncture by using functional magnetic resonance imaging (fMRI) Methods: Eighteen healthy right-handed volunteers participated in the experiment. The experiment used single block design, including rest state, stimulation state and post effect state (PE). Everyone only received acupuncture at one of the two stimulations, that was: true acupuncture (TA) at right Liv3 or sham acupoint (SA) near Liv3, in which 10 subjects participated in TA and other 8 subjects in SA. The fMRI data were obtained from scanning the whole brain and were analyzed using SPM99. Significant changes of stimulation state or post effect state compared to rest state were accessed using t-statistics. The t-ratios were used to form the statistical parametric maps which showed brain activation areas by acupuncture above P< 0.001. In order to remove the effects of other non-acupuncture factors, we used the mask function to exclude the areas activated by SA from the areas activated by TA. Results: The brain activation areas during TA for 10 subjects exclusive by SA for 8 subjects were showed on bilateral cerebella(t value is 10.06 and 9.82, respectively), prefrontal lobe (PF), superior parietal lobule (SPL, t value is 4.36 and 4.53, respectively) and inferior parietal lobule (IPL, t value is 3.94 and 4.95, respectively), occipital lobe, parahippocampal gyms, insula( t value is 3.82 and 5.51, respectively), thalamus, lentiform nucleus (t value is 3.24 and 4.40, respectively), contralateral temporal pole, anterior cingnlate cortex (ACC), and posterior cingulate cortex (PGC, all of P<0.01). The PE of TA for 10 subjects exclusive by 'PE' of SA for 8 subjects activated bilateral cerebella, PF, SPL, IPL, occipital lobe, lentiform nucleus, parahippocampal gyrus, ipsilateral tempoaral pole, hippocampus, insula, thalamus, contralateral head of nucleus caudate, corpus callosum, ACC, and PCC. Conclusion

  19. Dexamethasone intravitreal implant in previously treated patients with diabetic macular edema : Subgroup analysis of the MEAD study

    OpenAIRE

    Augustin, A.J.; Kuppermann, B.D.; Lanzetta, P.; Loewenstein, A.; Li, X.; Cui, H.; Hashad, Y.; Whitcup, S.M.; Abujamra, S.; Acton, J.; Ali, F.; Antoszyk, A.; Awh, C.C.; Barak, A.; Bartz-Schmidt, K.U.

    2015-01-01

    Background Dexamethasone intravitreal implant 0.7?mg (DEX 0.7) was approved for treatment of diabetic macular edema (DME) after demonstration of its efficacy and safety in the MEAD registration trials. We performed subgroup analysis of MEAD study results to evaluate the efficacy and safety of DEX 0.7 treatment in patients with previously treated DME. Methods Three-year, randomized, sham-controlled phase 3 study in patients with DME, best-corrected visual acuity (BCVA) of 34?68 Early Treatment...

  20. Brain's reward circuits mediate itch relief. a functional MRI study of active scratching.

    Directory of Open Access Journals (Sweden)

    Alexandru D P Papoiu

    Full Text Available Previous brain imaging studies investigating the brain processing of scratching used an exogenous intervention mimicking scratching, performed not by the subjects themselves, but delivered by an investigator. In real life, scratching is a conscious, voluntary, controlled motor response to itching, which is directed to the perceived site of distress. In this study we aimed to visualize in real-time by brain imaging the core mechanisms of the itch-scratch cycle when scratching was performed by subjects themselves. Secondly, we aimed to assess the correlations between brain patterns of activation and psychophysical ratings of itch relief or pleasurability of scratching. We also compared the patterns of brain activity evoked by self-scratching vs. passive scratching. We used a robust tridimensional Arterial Spin Labeling fMRI technique that is less sensitive to motion artifacts: 3D gradient echo and spin echo (GRASE--Propeller. Active scratching was accompanied by a higher pleasurability and induced a more pronounced deactivation of the anterior cingulate cortex and insula, in comparison with passive scratching. A significant involvement of the reward system including the ventral tegmentum of the midbrain, coupled with a mechanism deactivating the periaqueductal gray matter (PAG, suggests that itch modulation operates in reverse to the mechanism known to suppress pain. Our findings not only confirm a role for the central networks processing reward in the pleasurable aspects of scratching, but also suggest they play a role in mediating itch relief.

  1. Candidate Biomarkers in Children with Autism Spectrum Disorder: A Review of MRI Studies

    Institute of Scientific and Technical Information of China (English)

    Dongyun Li; Hans-Otto Karnath; Xiu Xu

    2017-01-01

    Searching for effective biomarkers is one of the most challenging tasks in the research field of Autism Spectrum Disorder (ASD).Magnetic resonance imaging (MRI) provides a non-invasive and powerful tool for investigating changes in the structure,function,maturation,connectivity,and metabolism of the brain of children with ASD.Here,we review the more recent MRI studies in young children with ASD,aiming to provide candidate biomarkers for the diagnosis of childhood ASD.The review covers structural imaging methods,diffusion tensor imaging,resting-state functional MRI,and magnetic reso nance spectroscopy.Future advances in neuroimaging techniques,as well as cross-disciplinary studies and largescale collaborations will be needed for an integrated approach linking neuroimaging,genetics,and phenotypic data to allow the discovery of new,effective biomarkers.

  2. Analysis of MRI by fractals for prediction of sensory attributes: A case study in loin

    DEFF Research Database (Denmark)

    Caballero, Daniel; Antequera, Teresa; Caro, Andrés

    2018-01-01

    This study investigates the use of fractal algorithms to analyse MRI of meat products, specifically loin, in order to determine sensory parameters of loin. For that, the capability of different fractal algorithms was evaluated (Classical Fractal Algorithm, CFA; Fractal Texture Algorithm, FTA...... was analysed. Results on this study firstly demonstrate the capability of fractal algorithms to analyse MRI from meat product. Different combinations of the analysed techniques can be applied for predicting most sensory attributes of loins adequately (R > 0.5). However, the combination of SE, OPFTA and MLR...... offered the most appropriate results. Thus, it could be proposed as an alternative to the traditional food technology methods....

  3. Impact of Short Social Training on Prosocial Behaviors: An fMRI Study.

    Science.gov (United States)

    Lukinova, Evgeniya; Myagkov, Mikhail

    2016-01-01

    Efficient brain-computer interfaces (BCIs) are in need of knowledge about the human brain and how it interacts, plays games, and socializes with other brains. A breakthrough can be achieved by revealing the microfoundations of sociality, an additional component of the utility function reflecting the value of contributing to group success derived from social identity. Building upon our previous behavioral work, we conduct a series of functional magnetic resonance imaging (fMRI) experiments (N = 10 in the Pilot Study and N = 15 in the Main Study) to measure whether and how sociality alters the functional activation of and connectivity between specific systems in the brain. The overarching hypothesis of this study is that sociality, even in a minimal form, serves as a natural mechanism of sustainable cooperation by fostering interaction between brain regions associated with social cognition and those related to value calculation. We use group-based manipulations to induce varying levels of sociality and compare behavior in two social dilemmas: Prisoner's Dilemma and variations of Ultimatum Game. We find that activation of the right inferior frontal gyrus, a region previously associated with cognitive control and modulation of the valuation system, is correlated with activity in the medial prefrontal cortex (mPFC) to a greater degree when participants make economic decisions in a game with an acquaintance, high sociality condition, compared to a game with a random individual, low sociality condition. These initial results suggest a specific biological mechanism through which sociality facilitates cooperation, fairness and provision of public goods at the cost of individual gain. Future research should examine neural dynamics in the brain during the computation of utility in the context of strategic games that involve social interaction for a larger sample of subjects.

  4. Contradictory Reasoning Network: An EEG and fMRI Study

    Science.gov (United States)

    Thai, Ngoc Jade; Seri, Stefano; Rotshtein, Pia; Tecchio, Franca

    2014-01-01

    Contradiction is a cornerstone of human rationality, essential for everyday life and communication. We investigated electroencephalographic (EEG) and functional magnetic resonance imaging (fMRI) in separate recording sessions during contradictory judgments, using a logical structure based on categorical propositions of the Aristotelian Square of Opposition (ASoO). The use of ASoO propositions, while controlling for potential linguistic or semantic confounds, enabled us to observe the spatial temporal unfolding of this contradictory reasoning. The processing started with the inversion of the logical operators corresponding to right middle frontal gyrus (rMFG-BA11) activation, followed by identification of contradictory statement associated with in the right inferior frontal gyrus (rIFG-BA47) activation. Right medial frontal gyrus (rMeFG, BA10) and anterior cingulate cortex (ACC, BA32) contributed to the later stages of process. We observed a correlation between the delayed latency of rBA11 response and the reaction time delay during inductive vs. deductive reasoning. This supports the notion that rBA11 is crucial for manipulating the logical operators. Slower processing time and stronger brain responses for inductive logic suggested that examples are easier to process than general principles and are more likely to simplify communication. PMID:24667491

  5. Normal anatomy of the anal wall and perianal spaces: An EUS, MRI and cadaveric correlative study

    International Nuclear Information System (INIS)

    Chung, Soo Young; Ryu, Sie Tae; Park, Ki Soon; Lee, Yul; Bae, Sang Hoon; Kang, Heung Sik

    1994-01-01

    To understand the normal endosonographic anatomy of the perianal spaces, and to evaluate the diagnostic efficacy and limitation of endorectal sonography(EUS), correlative study with MRI, cadaveric sectional image and cadaveric MRI were performed. EUS images of the normal 6 perianal spaces (pelvirectal, ischiorectal, intersphincteric, subcutaneous, central, submucous space) which were bounded by internal and external anal sphincters, rectal wall and levator ani muscle were correlated with MRI in 10 normal persons, cadaveric sectional images and cadaveric MRI in 2 cadavers. Pelvirectal space located superior to levator ani muscle could be demonstrable only on anterior wall scan but could not be visualized on lateral or posterior wall scan on EUS. Five perianal spaces located inferior to levator ani muscle were well seen on anterior, lateral, and posterior wall EUS. MRI was superior to EUS in the evaluation of pelvirectal and ischiorectal spaces but equal or inferior to EUS in the evaluation of intersphincteric, subcutaneous, central and submucous spaces. EUS was valuable in the evaluation of perianal spaces inferior to levator ani muscle but was limited in the evaluation of perianal spaces superior to levator ani muscle

  6. Multi institutional quantitative phantom study of yttrium-90 PET in PET/MRI: the MR-QUEST study.

    Science.gov (United States)

    Maughan, Nichole M; Eldib, Mootaz; Faul, David; Conti, Maurizio; Elschot, Mattijs; Knešaurek, Karin; Leek, Francesca; Townsend, David; DiFilippo, Frank P; Jackson, Kimberly; Nekolla, Stephan G; Lukas, Mathias; Tapner, Michael; Parikh, Parag J; Laforest, Richard

    2018-04-04

    Yttrium-90 ( 90 Y) radioembolization involves the intra-arterial delivery of radioactive microspheres to treat hepatic malignancies. Though this therapy involves careful pre-treatment planning and imaging, little is known about the precise location of the microspheres once they are administered. Recently, there has been growing interest post-radioembolization imaging using positron-emission tomography (PET) for quantitative dosimetry and identifying lesions that may benefit from additional salvage therapy. In this study, we aim to measure the inter-center variability of 90 Y PET measurements as measured on PET/MRI in preparation for a multi-institutional prospective phase I/II clinical trial. Eight institutions participated in this study and followed a standardized phantom filling and imaging protocol. The NEMA NU2-2012 body phantom was filled with 3 GBq of 90 Y chloride solution. The phantom was imaged for 30 min in listmode on a Siemens Biograph mMR non-TOF PET/MRI scanner at five time points across 10 days (0.3-3.0 GBq). Raw PET data were sent to a central site for image reconstruction and data analysis. Images were reconstructed with optimal parameters determined from a previous study. Volumes of interest (VOIs) matching the known sphere diameters were drawn on the vendor-provided attenuation map and propagated to the PET images. Recovery coefficients (RCs) and coefficient of variation of the RCs (COV) were calculated from these VOIs for each sphere size and activity level. Mean RCs ranged from 14.5 to 75.4%, with the lowest mean RC coming from the smallest sphere (10 mm) on the last day of imaging (0.16 MBq/ml) and the highest mean RC coming from the largest sphere (37 mm) on the first day of imaging (2.16 MBq/ml). The smaller spheres tended to exhibit higher COVs. In contrast, the larger spheres tended to exhibit lower COVs. COVs from the 37 mm sphere were  25%. Post-radioembolization dosimetry of lesions or other VOIs ≥ 22 mm in diameter can

  7. Brain Correlates of Aesthetic Expertise: A Parametric fMRI Study

    Science.gov (United States)

    Kirk, Ulrich; Skov, Martin; Christensen, Mark Schram; Nygaard, Niels

    2009-01-01

    Several studies have demonstrated that acquired expertise influences aesthetic judgments. In this paradigm we used functional magnetic resonance imaging (fMRI) to study aesthetic judgments of visually presented architectural stimuli and control-stimuli (faces) for a group of architects and a group of non-architects. This design allowed us to test…

  8. Brain correlates of aesthetic expertise: A parametric fMRI study

    DEFF Research Database (Denmark)

    Kirk, Ulrich; Skov, Martin; Christensen, Mark Schram

    2009-01-01

    Several studies have demonstrated that acquired expertise influences aesthetic judgments. In this paradigm we used functional magnetic resonance imaging (fMRI) to study aesthetic judgments of visually presented architectural stimuli and control-stimuli (faces) for a group of architects and a grou...

  9. Multimodal MRI for early diabetic mild cognitive impairment: study protocol of a prospective diagnostic trial

    International Nuclear Information System (INIS)

    Yu, Ying; Sun, Qian; Yan, Lin-Feng; Hu, Yu-Chuan; Nan, Hai-Yan; Yang, Yang; Liu, Zhi-Cheng; Wang, Wen; Cui, Guang-Bin

    2016-01-01

    Type 2 diabetes mellitus (T2DM) is a risk factor for dementia. Mild cognitive impairment (MCI), an intermediary state between normal cognition and dementia, often occurs during the prodromal diabetic stage, making early diagnosis and intervention of MCI very important. Latest neuroimaging techniques revealed some underlying microstructure alterations for diabetic MCI, from certain aspects. But there still lacks an integrated multimodal MRI system to detect early neuroimaging changes in diabetic MCI patients. Thus, we intended to conduct a diagnostic trial using multimodal MRI techniques to detect early diabetic MCI that is determined by the Montreal Cognitive Assessment (MoCA). In this study, healthy controls, prodromal diabetes and diabetes subjects (53 subjects/group) aged 40-60 years will be recruited from the physical examination center of Tangdu Hospital. The neuroimaging and psychometric measurements will be repeated at a 0.5 year-interval for 2.5 years’ follow-up. The primary outcome measures are 1) Microstructural and functional alterations revealed with multimodal MRI scans including structure magnetic resonance imaging (sMRI), resting state functional magnetic resonance imaging (rs-fMRI), diffusion kurtosis imaging (DKI), and three-dimensional pseudo-continuous arterial spin labeling (3D-pCASL); 2) Cognition evaluation with MoCA. The second outcome measures are obesity, metabolic characteristics, lifestyle and quality of life. The study will provide evidence for the potential use of multimodal MRI techniques with psychometric evaluation in diagnosing MCI at prodromal diabetic stage so as to help decision making in early intervention and improve the prognosis of T2DM. This study has been registered to ClinicalTrials.gov (NCT02420470) on April 2, 2015 and published on July 29, 2015

  10. Real-time fMRI neurofeedback to down-regulate superior temporal gyrus activity in patients with schizophrenia and auditory hallucinations: a proof-of-concept study.

    Science.gov (United States)

    Orlov, Natasza D; Giampietro, Vincent; O'Daly, Owen; Lam, Sheut-Ling; Barker, Gareth J; Rubia, Katya; McGuire, Philip; Shergill, Sukhwinder S; Allen, Paul

    2018-02-12

    Neurocognitive models and previous neuroimaging work posit that auditory verbal hallucinations (AVH) arise due to increased activity in speech-sensitive regions of the left posterior superior temporal gyrus (STG). Here, we examined if patients with schizophrenia (SCZ) and AVH could be trained to down-regulate STG activity using real-time functional magnetic resonance imaging neurofeedback (rtfMRI-NF). We also examined the effects of rtfMRI-NF training on functional connectivity between the STG and other speech and language regions. Twelve patients with SCZ and treatment-refractory AVH were recruited to participate in the study and were trained to down-regulate STG activity using rtfMRI-NF, over four MRI scanner visits during a 2-week training period. STG activity and functional connectivity were compared pre- and post-training. Patients successfully learnt to down-regulate activity in their left STG over the rtfMRI-NF training. Post- training, patients showed increased functional connectivity between the left STG, the left inferior prefrontal gyrus (IFG) and the inferior parietal gyrus. The post-training increase in functional connectivity between the left STG and IFG was associated with a reduction in AVH symptoms over the training period. The speech-sensitive region of the left STG is a suitable target region for rtfMRI-NF in patients with SCZ and treatment-refractory AVH. Successful down-regulation of left STG activity can increase functional connectivity between speech motor and perception regions. These findings suggest that patients with AVH have the ability to alter activity and connectivity in speech and language regions, and raise the possibility that rtfMRI-NF training could present a novel therapeutic intervention in SCZ.

  11. Occipital Lobe Gray Matter Volume in Male Patients with Chronic Schizophrenia: A Quantitative MRI Study

    Science.gov (United States)

    Onitsuka, Toshiaki; McCarley, Robert W.; Kuroki, Noriomi; Dickey, Chandlee C.; Kubicki, Marek; Demeo, Susan S.; Frumin, Melissa; Kikinis, Ron; Jolesz, Ferenc A.; Shenton, Martha E.

    2008-01-01

    Schizophrenia is characterized by deficits in cognition as well as visual perception. There have, however, been few magnetic resonance imaging (MRI) studies of the occipital lobe as an anatomically defined region of interest in schizophrenia. To examine whether or not patients with chronic schizophrenia show occipital lobe volume abnormalities, we measured gray matter volumes for both the primary visual area (PVA) and the visual association areas (VAA) using MRI based neuroanatomical landmarks and three-dimensional information. PVA and VAA gray matter volumes were measured using high-spatial resolution MRI in 25 male patients diagnosed with chronic schizophrenia and in 28 male normal controls. Chronic schizophrenia patients showed reduced bilateral VAA gray matter volume (11%), compared with normal controls, whereas patients showed no group difference in PVA gray matter volume. These results suggest that reduced bilateral VAA may be a neurobiological substrate of some of the deficits observed in early visual processing in schizophrenia. PMID:17350226

  12. A follow-up study by CT and MRI in 3 cases of Japanese encephalitis

    International Nuclear Information System (INIS)

    Shoji, H.; Murakami, T.; Murai, I.; Kida, H.; Sato, Y.; Kojima, K.; Abe, T.; Okudera, T.

    1990-01-01

    A follow-up study by CT and MRI in 3 cases of Japanese encephalitis (JE) was performed. Neurologically dementia, forced laughing, tetraplegia and parkinsonism were observed as sequelae. In the CT and MR scans about 3 years after the onset of JE, low-density areas (LDAs) or abnormal signal intensities had remained in the thalamus and basal ganglia. The abnormalities were also found in the brain stem. When the main lesions shown by CT and MRI were compared with those of the acute stage, T2-weighted MRI clearly revealed multiple small areas with high signal intensities, although the ones at the acute stage had showed diffuse abnormal signals. These findings may be useful in helping to identity a long time after the onset. (orig.)

  13. Modelling large motion events in fMRI studies of patients with epilepsy

    DEFF Research Database (Denmark)

    Lemieux, Louis; Salek-Haddadi, Afraim; Lund, Torben E

    2007-01-01

    -positive activation. Head motion can lead to severe image degradation and result in false-positive activation and is usually worse in patients than in healthy subjects. We performed general linear model fMRI data analysis on simultaneous EEG-fMRI data acquired in 34 cases with focal epilepsy. Signal changes...... associated with large inter-scan motion events (head jerks) were modelled using modified design matrices that include 'scan nulling' regressors. We evaluated the efficacy of this approach by mapping the proportion of the brain for which F-tests across the additional regressors were significant. In 95......% of cases, there was a significant effect of motion in 50% of the brain or greater; for the scan nulling effect, the proportion was 36%; this effect was predominantly in the neocortex. We conclude that careful consideration of the motion-related effects in fMRI studies of patients with epilepsy is essential...

  14. Functional and structural abnormalities associated with empathy in patients with schizophrenia: An fMRI and VBM study

    OpenAIRE

    Singh, Sadhana; Modi, Shilpi; Goyal, Satnam; Kaur, Prabhjot; Singh, Namita; Bhatia, Triptish; Deshpande, Smita N; Khushu, Subash

    2015-01-01

    Empathy deficit is a core feature of schizophrenia which may lead to social dysfunction. The present study was carried out to investigate functional and structural abnormalities associated with empathy in patients with schizophrenia using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). A sample of 14 schizophrenia patients and 14 healthy control subjects matched for age, sex and education were examined with structural high-resolution T1-weighted MRI; fMRI image...

  15. Strategic Motives Drive Proposers to Offer Fairly in Ultimatum Games: An fMRI Study.

    Science.gov (United States)

    Chen, Yin-Hua; Chen, Ying-Chun; Kuo, Wen-Jui; Kan, Kamhon; Yang, C C; Yen, Nai-Shing

    2017-04-03

    The hypothesis of strategic motives postulates that offering fairly in the Ultimatum Game (UG) is to avoid rejection and receive money. In this fMRI study, we used a modified UG to elucidate how proposers reached decisions of offering fairly and to what extent they considered offering selfishly with different stakes. We had proposers choose between a fair and a selfish offer with different degrees of selfishness and stake sizes. Proposers were less likely and spent more time choosing the fair offer over a slightly-selfish offer than a very selfish offer independent of stakes. Such choices evoked greater activation in the dorsal anterior cingulate cortices that typically involve in allocation of cognitive control for cost/benefit decision making. Choosing a fair offer in higher stakes evoked greater activation in the anterior cingulate gyrus (ACCg) and the areas that previously have been implicated in reward and theory of mind. Furthermore, choosing a slightly selfish offer over a fair offer evoked greater activation in the anterior cingulate sulcus, ACCg, ventral tegmental area (or substantia nigra) and anterior insular cortex signalling the higher gain and implying higher rejection risk. In conclusion, our findings favoured the hypothesis that proposers offer fairly based on the strategic motives.

  16. Attention and amygdala activity: an fMRI study with spider pictures in spider phobia.

    Science.gov (United States)

    Alpers, Georg W; Gerdes, Antje B M; Lagarie, Bernadette; Tabbert, Katharina; Vaitl, Dieter; Stark, Rudolf

    2009-06-01

    Facilitated detection of threatening visual cues is thought to be adaptive. In theory, detection of threat cues should activate the amygdala independently from allocation of attention. However, previous studies using emotional facial expressions as well as phobic cues yielded contradictory results. We used fMRI to examine whether the allocation of attention to components of superimposed spider and bird displays modulates amygdala activation. Nineteen spider-phobic women were instructed to identify either a moving or a stationary animal in briefly presented double-exposure displays. Amygdala activation followed a dose-response relationship: Compared to congruent neutral displays (two birds), amygdala activation was most pronounced in response to congruent phobic displays (two spiders) and less but still significant in response to mixed displays (spider and bird) when attention was focused on the phobic component. When attention was focused on the neutral component, mixed displays did not result in significant amygdala activation. This was confirmed in a significant parametric graduation of the amygdala activation in the order of congruent phobic displays, mixed displays with attention focus on the spider, mixed displays with focus on the bird and congruent neutral displays. These results challenge the notion that amygdala activation in response to briefly presented phobic cues is independent from attention.

  17. The neural correlates of internal and external comparisons: an fMRI study.

    Science.gov (United States)

    Wen, Xue; Xiang, Yanhui; Cant, Jonathan S; Wang, Tingting; Cupchik, Gerald; Huang, Ruiwang; Mo, Lei

    2017-01-01

    Many previous studies have suggested that various comparisons rely on the same cognitive and neural mechanisms. However, little attention has been paid to exploring the commonalities and differences between the internal comparison based on concepts or rules and the external comparison based on perception. In the present experiment, moral beauty comparison and facial beauty comparison were selected as the representatives of internal comparison and external comparison, respectively. Functional magnetic resonance imaging (fMRI) was used to record brain activity while participants compared the level of moral beauty of two scene drawings containing moral acts or the level of facial beauty of two face photos. In addition, a physical size comparison task with the same stimuli as the beauty comparison was included. We observed that both the internal moral beauty comparison and external facial beauty comparison obeyed a typical distance effect and this behavioral effect recruited a common frontoparietal network involved in comparisons of simple physical magnitudes such as size. In addition, compared to external facial beauty comparison, internal moral beauty comparison induced greater activity in more advanced and complex cortical regions, such as the bilateral middle temporal gyrus and middle occipital gyrus, but weaker activity in the putamen, a subcortical region. Our results provide novel neural evidence for the comparative process and suggest that different comparisons may rely on both common cognitive processes as well as distinct and specific cognitive components.

  18. Brain parenchymal damage in neuromyelitis optica spectrum disorder - A multimodal MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Pache, F.; Paul, F. [Max Delbrueck Center for Molecular Medicine and Charite Universitaetsmedizin Berlin, NeuroCure Clinical Research Center and Experimental and Clinical Research Center, Berlin (Germany); Charite Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Zimmermann, H.; Lacheta, A.; Papazoglou, S.; Kuchling, J.; Wuerfel, J.; Brandt, A.U. [Max Delbrueck Center for Molecular Medicine and Charite Universitaetsmedizin Berlin, NeuroCure Clinical Research Center and Experimental and Clinical Research Center, Berlin (Germany); Finke, C. [Charite Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Humboldt-Universitaet zu Berlin, Berlin School of Mind and Brain, Berlin (Germany); Hamm, B. [Charite Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany); Ruprecht, K. [Charite Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Scheel, M. [Max Delbrueck Center for Molecular Medicine and Charite Universitaetsmedizin Berlin, NeuroCure Clinical Research Center and Experimental and Clinical Research Center, Berlin (Germany); Charite Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany)

    2016-12-15

    To investigate different brain regions for grey (GM) and white matter (WM) damage in a well-defined cohort of neuromyelitis optica spectrum disorder (NMOSD) patients and compare advanced MRI techniques (VBM, Subcortical and cortical analyses (Freesurfer), and DTI) for their ability to detect damage in NMOSD. We analyzed 21 NMOSD patients and 21 age and gender matched control subjects. VBM (GW/WM) and DTI whole brain (TBSS) analyses were performed at different statistical thresholds to reflect different statistical approaches in previous studies. In an automated atlas-based approach, Freesurfer and DTI results were compared between NMOSD and controls. DTI TBSS and DTI atlas based analysis demonstrated microstructural impairment only within the optic radiation or in regions associated with the optic radiation (posterior thalamic radiation p < 0.001, 6.9 % reduction of fractional anisotropy). VBM demonstrated widespread brain GM and WM reduction, but only at exploratory statistical thresholds, with no differences remaining after correction for multiple comparisons. Freesurfer analysis demonstrated no group differences. NMOSD specific parenchymal brain damage is predominantly located in the optic radiation, likely due to a secondary degeneration caused by ON. In comparison, DTI appears to be the most reliable and sensitive technique for brain damage detection in NMOSD. (orig.)

  19. Brain parenchymal damage in neuromyelitis optica spectrum disorder - A multimodal MRI study

    International Nuclear Information System (INIS)

    Pache, F.; Paul, F.; Zimmermann, H.; Lacheta, A.; Papazoglou, S.; Kuchling, J.; Wuerfel, J.; Brandt, A.U.; Finke, C.; Hamm, B.; Ruprecht, K.; Scheel, M.

    2016-01-01

    To investigate different brain regions for grey (GM) and white matter (WM) damage in a well-defined cohort of neuromyelitis optica spectrum disorder (NMOSD) patients and compare advanced MRI techniques (VBM, Subcortical and cortical analyses (Freesurfer), and DTI) for their ability to detect damage in NMOSD. We analyzed 21 NMOSD patients and 21 age and gender matched control subjects. VBM (GW/WM) and DTI whole brain (TBSS) analyses were performed at different statistical thresholds to reflect different statistical approaches in previous studies. In an automated atlas-based approach, Freesurfer and DTI results were compared between NMOSD and controls. DTI TBSS and DTI atlas based analysis demonstrated microstructural impairment only within the optic radiation or in regions associated with the optic radiation (posterior thalamic radiation p < 0.001, 6.9 % reduction of fractional anisotropy). VBM demonstrated widespread brain GM and WM reduction, but only at exploratory statistical thresholds, with no differences remaining after correction for multiple comparisons. Freesurfer analysis demonstrated no group differences. NMOSD specific parenchymal brain damage is predominantly located in the optic radiation, likely due to a secondary degeneration caused by ON. In comparison, DTI appears to be the most reliable and sensitive technique for brain damage detection in NMOSD. (orig.)

  20. Initial study on in vivo conductivity mapping of breast cancer using MRI.

    Science.gov (United States)

    Shin, Jaewook; Kim, Min Jung; Lee, Joonsung; Nam, Yoonho; Kim, Min-Oh; Choi, Narae; Kim, Sooyeon; Kim, Dong-Hyun

    2015-08-01

    To develop and apply a method to measure in vivo electrical conductivity values using magnetic resonance imaging (MRI) in subjects with breast cancer. A recently developed technique named MREPT (MR electrical properties tomography) together with a novel coil combination process was used to quantify the conductivity values. The overall technique was validated using a phantom study. In addition, 90 subjects were imaged (50 subjects with previously biopsy-confirmed breast tumor and 40 normal subjects), which was approved by our institutional review board (IRB). A routine clinical protocol, specifically a T2 -weighted FSE (fast spin echo) imaging data, was used for reconstruction of conductivity. By employing the coil combination, the relative error in the conductivity map was reduced from ~70% to 10%. The average conductivity values in breast cancers regions (0.89 ± 0.33S/m) was higher compared to parenchymal tissue (0.43 S/m, P conductivity compared to benign cases (0.56 S/m, n = 5) (P conductivity compared to in situ cancers (0.57 S/m) (P conductivity mapping of breast cancers is feasible using a noninvasive in vivo MREPT technique combined with a coil combination process. The method may provide a tool in the MR diagnosis of breast cancer. © 2014 Wiley Periodicals, Inc.

  1. Youth suicide: an insight into previous hospitalisation for injury and sociodemographic conditions from a nationwide cohort study.

    Science.gov (United States)

    Zambon, Francesco; Laflamme, Lucie; Spolaore, Paolo; Visentin, Cristiana; Hasselberg, Marie

    2011-06-01

    This study investigates the degree to which a previous hospitalisation for injury of any intent is a risk of subsequent youth suicide and whether this association is influenced by family socioeconomic status or economic stress. A nationwide register-based cohort study was conducted covering all Swedish subjects born between January 1977 and December 1991 (N=1,616,342, male/female ratio=1.05). The cohort subjects were followed-up from January 1998 to December 2003, when aged 7-26 years. Poisson regression and the likelihood ratio test (95% CI) were used to assess the age-adjusted effect of hospitalisation for injuries of various intent on youth suicide and its effect once adjusted for family sociodemographic and social circumstances. Each set of exposures was associated independently and significantly with suicide mortality. Being hospitalised for self-inflicted injuries or injuries of undetermined intent was associated with a risk of suicide 36 to 47 times, respectively, that of subjects never hospitalised in the period under study (95% CI 28.36 to 45.58 and 26.67 to 83.87 for self-inflicted injuries and for events of undetermined intent, respectively; overall psuicide (RR 3.08; 95% CI 2.26 to 4.19). These effects were solid and not substantially altered after adjustment for family demographic and socioeconomic circumstances. A strong association exists between previous hospitalisation for injury of any intent and youth suicide. The association is robust and unaltered by family socioeconomic circumstances.

  2. Comparison of 18F-FDG PET/MRI and MRI alone for whole-body staging and potential impact on therapeutic management of women with suspected recurrent pelvic cancer: a follow-up study.

    Science.gov (United States)

    Sawicki, Lino M; Kirchner, Julian; Grueneisen, Johannes; Ruhlmann, Verena; Aktas, Bahriye; Schaarschmidt, Benedikt M; Forsting, Michael; Herrmann, Ken; Antoch, Gerald; Umutlu, Lale

    2018-04-01

    To evaluate the diagnostic performance of 18 F-FDG PET/MRI for whole-body staging and potential changes in therapeutic management of women with suspected recurrent pelvic cancer in comparison with MRI alone. Seventy-one consecutive women (54 ± 13 years, range: 25-80 years) with suspected recurrence of cervical (32), ovarian (26), endometrial (7), vulvar (4), and vaginal (2) cancer underwent PET/MRI including a diagnostic contrast-enhanced MRI protocol. PET/MRI and MRI datasets were separately evaluated regarding lesion count, localization, categorization (benign/malignant), and diagnostic confidence (3-point scale; 1-3) by two physicians. The reference standard was based on histopathology results and follow-up imaging. Diagnostic accuracy and proportions of malignant and benign lesions rated correctly were retrospectively compared using McNemar's chi 2 test. Differences in diagnostic confidence were assessed by Wilcoxon test. Fifty-five patients showed cancer recurrence. PET/MRI correctly identified more patients with cancer recurrence than MRI alone (100% vs. 83.6%, p PET/MRI, MRI alone missed 4/15 patients with pelvic recurrence and miscategorized 8/40 patients with distant metastases as having local recurrence only. Based on the reference standard, 241 lesions were detected in the study cohort (181 malignant, 60 benign). While PET/MRI provided correct identification of 181/181 (100%) malignant lesions, MRI alone correctly identified 135/181 (74.6%) malignant lesions, which was significantly less compared to PET/MRI (p PET/MRI offered superior diagnostic accuracy (99.2% vs. 79.3%, p PET/MRI demonstrates excellent diagnostic performance and outperforms MRI alone for whole-body staging of women with suspected recurrent pelvic cancer, indicating potential changes in therapy management based on evaluation of local recurrence and distant metastatic spread.

  3. A longitudinal study of cerebral glucose metabolism, MRI, and disability in patients with MS

    DEFF Research Database (Denmark)

    Blinkenberg, M; Jensen, C.V.; Holm, S

    1999-01-01

    OBJECTIVE: To study the time-related changes in cerebral metabolic rate of glucose (CMRglc) in MS patients and to correlate these with changes in MRI lesion load and disability. BACKGROUND: Measurements of MRI lesion load and neurologic disability are used widely to monitor disease progression...... and parietal cortical areas. There was a statistically significant increase of disability (pmetabolism in MS is decreased significantly during a 2......-year observation period, suggesting a deterioration of cortical activity with disease progression. The time-related changes of cortical CMRglc are statistically stronger than changes in TLA measurements and neurologic disability, and might be a useful secondary measure of treatment efficacy...

  4. Interactive scan control for kinematic study in open MRI

    International Nuclear Information System (INIS)

    Goto, Tomohiro; Hamada, Kiyomi; Ito, Taeko; Nagao, Hisako; Takahashi, Tetsuhiko; Hayashida, Yoshiko; Hiai, Yasuhiro; Yamashita, Yasuyuki

    2007-01-01

    A tool to support the subject is generally used for kinematic joint imaging with an open MRI apparatus because of difficulty setting the image plane correctly. However, use of a support tool requires a complicated procedure to position the subject, and setting the image plane when the joint angle changes is time consuming. Allowing the subject to move freely enables better diagnoses when kinematic joint imaging is performed. We therefore developed an interactive scan control (ISC) to facilitate the easy, quick, and accurate setting of the image plane even when a support tool is not used. We used a 0.4T magnetic resonance (MR) imaging system open in the horizontal direction. The ISC determines the image plane interactively on the basis of fluoroscopy images displayed on a user interface. The imaging pulse is a balanced steady-state acquisition with rewound gradient echo (SARGE) sequence with update time less than 2 s. Without using a tool to support the knee, we positioned the knee of a healthy volunteer at 4 different joint angles and set the image plane through the patella and femur at each of the angles. Lumbar imaging is also demonstrated with ISC. Setting the image plane was easy and quick at all knee angles, and images obtained clearly showed the patella and femur. Total imaging time was less than 10 min, a fourth of the time needed when a support tool is used. We also used our ISC in kinematic imaging of the lumbar. The ISC shortens total time for kinematic joint imaging, and because a support tool is not needed, imaging can be done more freely in an open MR imaging apparatus. (author)

  5. Previous Fractures at Multiple Sites Increase the Risk for Subsequent Fractures: The Global Longitudinal Study of Osteoporosis in Women

    Science.gov (United States)

    Gehlbach, Stephen; Saag, Kenneth G.; Adachi, Jonathan D.; Hooven, Fred H.; Flahive, Julie; Boonen, Steven; Chapurlat, Roland D.; Compston, Juliet E.; Cooper, Cyrus; Díez-Perez, Adolfo; Greenspan, Susan L.; LaCroix, Andrea Z.; Netelenbos, J. Coen; Pfeilschifter, Johannes; Rossini, Maurizio; Roux, Christian; Sambrook, Philip N.; Silverman, Stuart; Siris, Ethel S.; Watts, Nelson B.; Lindsay, Robert

    2016-01-01

    Previous fractures of the hip, spine, or wrist are well-recognized predictors of future fracture, but the role of other fracture sites is less clear. We sought to assess the relationship between prior fracture at 10 skeletal locations and incident fracture. The Global Longitudinal Study of Osteoporosis in Women (GLOW) is an observational cohort study being conducted in 17 physician practices in 10 countries. Women ≥ 55 years answered questionnaires at baseline and at 1 and/or 2 years (fractures in previous year). Of 60,393 women enrolled, follow-up data were available for 51,762. Of these, 17.6%, 4.0%, and 1.6% had suffered 1, 2, or ≥3 fractures since age 45. During the first 2 years of follow-up, 3149 women suffered 3683 incident fractures. Compared with women with no prior fractures, women with 1, 2, or ≥ 3 prior fractures were 1.8-, 3.0-, and 4.8-fold more likely to have any incident fracture; those with ≥3 prior fractures were 9.1-fold more likely to sustain a new vertebral fracture. Nine of 10 prior fracture locations were associated with an incident fracture. The strongest predictors of incident spine and hip fractures were prior spine fracture (hazard ratio 7.3) and hip (hazard ratio 3.5). Prior rib fractures were associated with a 2.3-fold risk of subsequent vertebral fracture, previous upper leg fracture predicted a 2.2-fold increased risk of hip fracture; women with a history of ankle fracture were at 1.8-fold risk of future fracture of a weight-bearing bone. Our findings suggest that a broad range of prior fracture sites are associated with an increased risk of incident fractures, with important implications for clinical assessments and risk model development. PMID:22113888

  6. Previous experiences and emotional baggage as barriers to lifestyle change - a qualitative study of Norwegian Healthy Life Centre participants.

    Science.gov (United States)

    Følling, Ingrid S; Solbjør, Marit; Helvik, Anne-S

    2015-06-23

    Changing lifestyle is challenging and difficult. The Norwegian Directorate of Health recommends that all municipalities establish Healthy Life Centres targeted to people with lifestyle issues. Little is known about the background, experiences and reflections of participants. More information is needed about participants to shape effective lifestyle interventions with lasting effect. This study explores how participants in a lifestyle intervention programme describe previous life experiences in relation to changing lifestyle. Semi-structured qualitative in-depth interviews were performed with 23 participants (16 women and 7 men) aged 18 - 70 years. The data were analysed using systematic text condensation searching for issues describing participants' responses, and looking for the essence, aiming to share the basis of life-world experiences as valid knowledge. Participants identified two main themes: being stuck in old habits, and being burdened with emotional baggage from their previous negative experiences. Participants expressed a wish to change their lifestyles, but were unable to act in accordance with the health knowledge they possessed. Previous experiences with lifestyle change kept them from initiating attempts without professional assistance. Participants also described being burdened by an emotional baggage with problems from childhood and/or with family, work and social life issues. Respondents said that they felt that emotional baggage was an important explanation for why they were stuck in old habits and that conversely, being stuck in old habits added load to their already emotional baggage and made it heavier. Behavioural change can be hard to perform as psychological distress from life baggage can influence the ability to change. The study participants' experience of being stuck in old habits and having substantial emotional baggage raises questions as to whether or not Healthy Life Centres are able to help participants who need to make a lifestyle

  7. Everolimus for Previously Treated Advanced Gastric Cancer: Results of the Randomized, Double-Blind, Phase III GRANITE-1 Study

    Science.gov (United States)

    Ohtsu, Atsushi; Ajani, Jaffer A.; Bai, Yu-Xian; Bang, Yung-Jue; Chung, Hyun-Cheol; Pan, Hong-Ming; Sahmoud, Tarek; Shen, Lin; Yeh, Kun-Huei; Chin, Keisho; Muro, Kei; Kim, Yeul Hong; Ferry, David; Tebbutt, Niall C.; Al-Batran, Salah-Eddin; Smith, Heind; Costantini, Chiara; Rizvi, Syed; Lebwohl, David; Van Cutsem, Eric

    2013-01-01

    Purpose The oral mammalian target of rapamycin inhibitor everolimus demonstrated promising efficacy in a phase II study of pretreated advanced gastric cancer. This international, double-blind, phase III study compared everolimus efficacy and safety with that of best supportive care (BSC) in previously treated advanced gastric cancer. Patients and Methods Patients with advanced gastric cancer that progressed after one or two lines of systemic chemotherapy were randomly assigned to everolimus 10 mg/d (assignment schedule: 2:1) or matching placebo, both given with BSC. Randomization was stratified by previous chemotherapy lines (one v two) and region (Asia v rest of the world [ROW]). Treatment continued until disease progression or intolerable toxicity. Primary end point was overall survival (OS). Secondary end points included progression-free survival (PFS), overall response rate, and safety. Results Six hundred fifty-six patients (median age, 62.0 years; 73.6% male) were enrolled. Median OS was 5.4 months with everolimus and 4.3 months with placebo (hazard ratio, 0.90; 95% CI, 0.75 to 1.08; P = .124). Median PFS was 1.7 months and 1.4 months in the everolimus and placebo arms, respectively (hazard ratio, 0.66; 95% CI, 0.56 to 0.78). Common grade 3/4 adverse events included anemia, decreased appetite, and fatigue. The safety profile was similar in patients enrolled in Asia versus ROW. Conclusion Compared with BSC, everolimus did not significantly improve overall survival for advanced gastric cancer that progressed after one or two lines of previous systemic chemotherapy. The safety profile observed for everolimus was consistent with that observed for everolimus in other cancers. PMID:24043745

  8. Functional MRI studies in human Ecstasy and cannabis users

    NARCIS (Netherlands)

    Jager, G.

    2006-01-01

    Cannabis and ecstasy are among the most widely used illicit drugs in the world. However, there are substantial concerns about their neurotoxic potential for brain and brain function. Despite previous research, some crucial questions regarding the causality, course and clinical relevance have

  9. No effects of MRI scan on male reproduction hormones.

    Science.gov (United States)

    Møllerløkken, Ole J; Moen, Bente E; Baste, Valborg; Magerøy, Nils; Oftedal, Gunnhild; Neto, Emanuel; Ersland, Lars; Bjørge, Line; Torjesen, Peter A; Mild, Kjell Hansson

    2012-08-01

    Magnetic resonance imaging (MRI) is increasing around the world and the possible adverse effects on reproductive health of electromagnetic fields (EMFs) in MRI are not previously studied. A prospective randomized balanced cross-over study using a head scan in real MRI with whole-body transmitting coil and sham MRI among 24 healthy male volunteers was conducted. Serum-blood samples of inhibin B, testosterone, prolactine, thyreotropine, luteinizing hormone, follicle stimulating hormone, sex-hormone binding globuline and estradiol were taken before and after the different scans. Neither immediately after, nor after 11 days were there seen any differences in the hormone levels comparing real and sham MRI. The lack of effects of EMF on male reproductive hormones should be reassuring to the public and especially for men examined in MRI. Adverse effects on other endpoints than male reproduction or possible chronic effect of multiple MRI scans have not been investigated in this study. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. An exploration of GPs' use of MRI: a critical incident study.

    Science.gov (United States)

    Robling, M; Kinnersley, P; Houston, H; Hourihan, M; Cohen, D; Hale, J

    1998-06-01

    Direct access to Magnetic Resonance Imaging (MRI) is becoming available to GPs in the UK, offering major benefits for the improved diagnosis and management of certain clinical conditions. Variations in usage of this service may be large, and effective locally produced guidelines are not currently available. The Department of General Practice is conducting a research programme to develop and evaluate methods to optimize MRI use by GPs. We aimed to describe the current use of MRI by GPs in South Glamorgan; to summarize their reasons for requesting MRI; and to produce criteria to assess the appropriateness of magnetic resonance (MR) scan requests. Using the critical incident technique, 25 GPs were interviewed about recent scans requested for patients with knee and lumbar spine complaints. A local panel of primary and secondary care doctors was convened to develop criteria for assessing MR scan requests. Sixty-two scan requests were discussed. Doctors' reasons for requesting MR scans were identified and classified. Reasons for requests included personal, contextual and biomedical variables. Fifteen patients (24%) were managed in primary care following MRI when otherwise they would have been referred. When referrals were made, GPs felt able to reinforce the request and occasionally to direct the patient somewhere more appropriate. The panel reviewed the interview data to produce objective criteria to assess scan requests. The criteria reflect the relative importance of non-biomedical variables in the decision to request MRI. The study identified those reasons which are important to GPs when requesting MR scans and the impact of this new technology upon patient management. Interview data have been used to inform locally developed consensus criteria, which will be made available as practice guidelines as the research programme progresses.

  11. The normal transverse mesocolon and involvement of the mesocolon in acute pancreatitis: an MRI study.

    Science.gov (United States)

    Chi, Xiao Xiao; Zhang, Xiao Ming; Chen, Tian Wu; Huang, Xiao Hua; Yang, Lin; Tang, Wei; Xiao, Bo

    2014-01-01

    To study the MRI findings of the normal transverse mesocolon and the involvement of the mesocolon in acute pancreatitis (AP) as well as the relationship between the involvement of the mesocolon and the severity of AP. Forty patients without pancreatic disorders were retrospectively analyzed to observe the normal transverse mesocolon using MRI; 210 patients with AP confirmed by clinical and laboratory tests were retrospectively analyzed using MRI to observe transverse-mesocolon involvement (TMI). The severity of TMI was recorded as zero points (no abnormalities and transverse-mesocolon vessel involvement), one point (linear and patchy signal in the transverse mesocolon) or two points (transverse-mesocolon effusion). The AP severity was graded by the MRI severity index (MRSI) and the Acute Physiology And Chronic Healthy Evaluation II (APACHE II) scoring system. The correlations of TMI with MRSI and APACHE-II were analyzed. In a normal transverse mesocolon, the display rates of the middle colic artery, the middle colic vein and the gastrocolic trunk on MRI were 95.0%, 82.5% and 100.0%, respectively. Of the 210 patients with AP, 130 patients (61.9%) had TMI. According to the TMI grading, 40%, 39% and 20% of the patients were graded at zero, one and two points, respectively. TMI was strongly correlated with the MRSI score (r = 0.759, P = 0.000) and the APACHE-II score (r = 0.384, P = 0.000). MRI could be used to visualize transverse-mesocolon involvement. The severity of TMI could reflect that of AP in the clinical setting and imaging. TMI might be a supplementary indicator of the severity of AP.

  12. 1.5 versus 3 versus 7 Tesla in abdominal MRI: A comparative study.

    Science.gov (United States)

    Laader, Anja; Beiderwellen, Karsten; Kraff, Oliver; Maderwald, Stefan; Wrede, Karsten; Ladd, Mark E; Lauenstein, Thomas C; Forsting, Michael; Quick, Harald H; Nassenstein, Kai; Umutlu, Lale

    2017-01-01

    The aim of this study was to investigate and compare the feasibility as well as potential impact of altered magnetic field properties on image quality and potential artifacts of 1.5 Tesla, 3 Tesla and 7 Tesla non-enhanced abdominal MRI. Magnetic Resonance (MR) imaging of the upper abdomen was performed in 10 healthy volunteers on a 1.5 Tesla, a 3 Tesla and a 7 Tesla MR system. The study protocol comprised a (1) T1-weighted fat-saturated spoiled gradient-echo sequence (2D FLASH), (2) T1-weighted fat-saturated volumetric interpolated breath hold examination sequence (3D VIBE), (3) T1-weighted 2D in and opposed phase sequence, (4) True fast imaging with steady-state precession sequence (TrueFISP) and (5) T2-weighted turbo spin-echo (TSE) sequence. For comparison reasons field of view and acquisition times were kept comparable for each correlating sequence at all three field strengths, while trying to achieve the highest possible spatial resolution. Qualitative and quantitative analyses were tested for significant differences. While 1.5 and 3 Tesla MRI revealed comparable results in all assessed features and sequences, 7 Tesla MRI yielded considerable differences in T1 and T2 weighted imaging. Benefits of 7 Tesla MRI encompassed an increased higher spatial resolution and a non-enhanced hyperintense vessel signal at 7 Tesla, potentially offering a more accurate diagnosis of abdominal parenchymatous and vasculature disease. 7 Tesla MRI was also shown to be more impaired by artifacts, including residual B1 inhomogeneities, susceptibility and chemical shift artifacts, resulting in reduced overall image quality and overall image impairment ratings. While 1.5 and 3 Tesla T2w imaging showed equivalently high image quality, 7 Tesla revealed strong impairments in its diagnostic value. Our results demonstrate the feasibility and overall comparable imaging ability of T1-weighted 7 Tesla abdominal MRI towards 3 Tesla and 1.5 Tesla MRI, yielding a promising diagnostic potential for

  13. Evidence for bilateral involvement in idiom comprehension : An fMRI study

    NARCIS (Netherlands)

    Zempleni, Monika-Zita; Haverkort, Marco; Renken, Remco; Stowe, Laurie A.

    2007-01-01

    The goal of the current study was to identify the neural substrate of idiom comprehension using fMRI. Idioms are familiar, fixed expressions whose meaning is not dependent on the literal interpretation of the component words. We presented literally plausible idioms in a sentence forcing a figurative

  14. An fMRI Study of the Social Competition in Healthy Subjects

    Science.gov (United States)

    Polosan, M.; Baciu, M.; Cousin, E.; Perrone, M.; Pichat, C.; Bougerol, T.

    2011-01-01

    Social interaction requires the ability to infer another person's mental state (Theory of Mind, ToM) and also executive functions. This fMRI study aimed to identify the cerebral correlates activated by ToM during a specific social interaction, the human-human competition. In this framework, we tested a conflict resolution task (Stroop) adapted to…

  15. Perceiving Age and Gender in Unfamiliar Faces: An fMRI Study on Face Categorization

    Science.gov (United States)

    Wiese, Holger; Kloth, Nadine; Gullmar, Daniel; Reichenbach, Jurgen R.; Schweinberger, Stefan R.

    2012-01-01

    Efficient processing of unfamiliar faces typically involves their categorization (e.g., into old vs. young or male vs. female). However, age and gender categorization may pose different perceptual demands. In the present study, we employed functional magnetic resonance imaging (fMRI) to compare the activity evoked during age vs. gender…

  16. A STUDY ON PERITUMORAL BRAIN EDEMA AROUND MENINGIOMAS BY MRI AND CONTRAST CT

    NARCIS (Netherlands)

    GO, KG; KAMMAN, RL; WILMINK, JT; MOOYAART, EL

    1994-01-01

    In the present study upon 9 meningiomas, the volume of peritumoral brain edema was calculated by integration of the cross-sectional edematous areas on serial MRI slices. It was zero in 3 cases and ranged from 11 to 176.4 ml in the other cases. There was disruption of the cortex in all cases, ranging

  17. Hearing loss associated with repeated MRI acquisition procedure-related acoustic noise exposure: an occupational cohort study

    NARCIS (Netherlands)

    Bongers, Suzan; Slottje, Pauline; Kromhout, Hans

    2017-01-01

    OBJECTIVE: To study the effects of repeated exposure to MRI-related acoustic noise during image acquisition procedures (scans) on hearing. METHODS: A retrospective occupational cohort study was performed among workers of an MRI manufacturing facility (n=474). Longitudinal audiometry data from the

  18. Comparison of MRI-based and CT/MRI fusion-based postimplant dosimetric analysis of prostate brachytherapy

    International Nuclear Information System (INIS)

    Tanaka, Osamu; Hayashi, Shinya; Matsuo, Masayuki; Sakurai, Kota; Nakano, Masahiro; Maeda, Sunaho; Kajita, Kimihiro R.T.; Deguchi, Takashi; Hoshi, Hiroaki

    2006-01-01

    Purpose: The aim of this study was to compare the outcomes between magnetic resonance imaging (MRI)-based and computed tomography (CT)/MRI fusion-based postimplant dosimetry methods in permanent prostate brachytherapy. Methods and Materials: Between October 2004 and March 2006, a total of 52 consecutive patients with prostate cancer were treated by brachytherapy, and postimplant dosimetry was performed using CT/MRI fusion. The accuracy and reproducibility were prospectively compared between MRI-based dosimetry and CT/MRI fusion-based dosimetry based on the dose-volume histogram (DVH) related parameters as recommended by the American Brachytherapy Society. Results: The prostate volume was 15.97 ± 6.17 cc (mean ± SD) in MRI-based dosimetry, and 15.97 ± 6.02 cc in CT/MRI fusion-based dosimetry without statistical difference. The prostate V100 was 94.5% and 93.0% in MRI-based and CT/MRI fusion-based dosimetry, respectively, and the difference was statistically significant (p = 0.002). The prostate D90 was 119.4% and 114.4% in MRI-based and CT/MRI fusion-based dosimetry, respectively, and the difference was statistically significant (p = 0.004). Conclusion: Our current results suggested that, as with fusion images, MR images allowed accurate contouring of the organs, but they tended to overestimate the analysis of postimplant dosimetry in comparison to CT/MRI fusion images. Although this MRI-based dosimetric discrepancy was negligible, MRI-based dosimetry was acceptable and reproducible in comparison to CT-based dosimetry, because the difference between MRI-based and CT/MRI fusion-based results was smaller than that between CT-based and CT/MRI fusion-based results as previously reported

  19. Emotional sensitivity, emotion regulation and impulsivity in borderline personality disorder: a critical review of fMRI studies.

    Science.gov (United States)

    van Zutphen, Linda; Siep, Nicolette; Jacob, Gitta A; Goebel, Rainer; Arntz, Arnoud

    2015-04-01

    Emotional sensitivity, emotion regulation and impulsivity are fundamental topics in research of borderline personality disorder (BPD). Studies using fMRI examining the neural correlates concerning these topics is growing and has just begun understanding the underlying neural correlates in BPD. However, there are strong similarities but also important differences in results of different studies. It is therefore important to know in more detail what these differences are and how we should interpret these. In present review a critical light is shed on the fMRI studies examining emotional sensitivity, emotion regulation and impulsivity in BPD patients. First an outline of the methodology and the results of the studies will be given. Thereafter important issues that remained unanswered and topics to improve future research are discussed. Future research should take into account the limited power of previous studies and focus more on BPD specificity with regard to time course responses, different regulation strategies, manipulation of self-regulation, medication use, a wider range of stimuli, gender effects and the inclusion of a clinical control group. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Doxorubicin and ifosfamide combination chemotherapy in previously treated acute leukemia in adults: a Southwest Oncology Group pilot study.

    Science.gov (United States)

    Ryan, D H; Bickers, J N; Vial, R H; Hussein, K; Bottomley, R; Hewlett, J S; Wilson, H E; Stuckey, W J

    1980-01-01

    The Southwest Oncology Group did a limited institutional pilot study of the combination of doxorubicin and ifosfamide in the treatment of previously treated adult patients with acute leukemia. Thirty-four patients received one or two courses of the combination. All patients had received prior chemotherapy and 32 had received prior anthracycline chemotherapy. Three patients died before their responses could be fully evaluated. Fourteen patients achieved complete remission (41%) and one patient achieved partial remission. The complete remission rate was 27% for patients with acute myeloblastic leukemia (myelomonoblastic leukemia, monoblastic leukemia, and erythroleukemia) and 89% for patients with acute lymphocytic and undifferentiated leukemia (ALL). Toxic effects included severe hematologic reactions in 33 of 34 patients, hematuria in six patients, altered sensorium in one patient, and congestive heart failure in one patient. The safety of the combination was established and toxic side effects of this therapy were tolerable. The 89% complete remission rate for previously treated patients with ALL suggests that the combination of doxorubicin and ifosfamide may be particularly effective in ALL.

  1. The suitability of XRF analysis for compositional classification of archaeological ceramic fabric: A comparison with a previous NAA study

    International Nuclear Information System (INIS)

    Padilla, R.; Espen, P. van; Torres, P.P. Godo

    2006-01-01

    The main drawbacks of EDXRF techniques, restricting its more frequent use for the specific purpose of compositional analysis of archaeological ceramic fabric, have been the insufficient sensitivity to determine some important elements (like Cr, REE, among others), a somewhat worse precision and the inability to perform standard-less quantitative procedures in the absence of suitable certified reference materials (CRM) for ceramic fabric. This paper presents the advantages of combining two energy dispersive X-ray fluorescence methods for fast and non-destructive analysis of ceramic fabric with increased sensitivity. Selective polarized excitation using secondary targets (EDPXRF) and radioisotope excitation (R-XRF) using a 241 Am source. The analytical performance of the methods was evaluated by analyzing several CRM of sediment type, and the fitness for the purpose of compositional classification was compared with that obtained by using Instrumental Neutron Activation Analysis in a previous study of Cuban aborigine pottery

  2. The suitability of XRF analysis for compositional classification of archaeological ceramic fabric: A comparison with a previous NAA study

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, R. [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear (CEADEN), Laboratorio de Analisis Quimico, Calle 30 no. 502, Playa, Ciudad Habana (Cuba)]. E-mail: roman.padilla@infomed.sld.cu; Espen, P. van [University of Antwerp (Belgium); Torres, P.P. Godo [Centro de Antropologia, Havana (Cuba)

    2006-02-03

    The main drawbacks of EDXRF techniques, restricting its more frequent use for the specific purpose of compositional analysis of archaeological ceramic fabric, have been the insufficient sensitivity to determine some important elements (like Cr, REE, among others), a somewhat worse precision and the inability to perform standard-less quantitative procedures in the absence of suitable certified reference materials (CRM) for ceramic fabric. This paper presents the advantages of combining two energy dispersive X-ray fluorescence methods for fast and non-destructive analysis of ceramic fabric with increased sensitivity. Selective polarized excitation using secondary targets (EDPXRF) and radioisotope excitation (R-XRF) using a {sup 241}Am source. The analytical performance of the methods was evaluated by analyzing several CRM of sediment type, and the fitness for the purpose of compositional classification was compared with that obtained by using Instrumental Neutron Activation Analysis in a previous study of Cuban aborigine pottery.

  3. Bevacizumab treatment in malignant meningioma with additional radiation necrosis. An MRI diffusion and perfusion case study

    Energy Technology Data Exchange (ETDEWEB)

    Bostroem, J.P. [University of Bonn Medical Center, Department of Neurosurgery, Bonn (Germany); MediClin Robert Janker Clinic and MVZ MediClin, Department of Radiosurgery and Stereotactic Radiotherapy, Bonn (Germany); Seifert, M.; Greschus, S. [University of Bonn Medical Center, Department of Radiology, Bonn (Germany); Schaefer, N.; Herrlinger, U. [University of Bonn Medical Center, Division of Clinical Neurooncology, Department of Neurology, Bonn (Germany); Glas, M. [University of Bonn Medical Center, Division of Clinical Neurooncology, Department of Neurology, Bonn (Germany); University of Bonn Medical Center, Stem Cell Pathologies, Institute of Reconstructive Neurobiology, Bonn (Germany); MediClin Robert Janker Clinic, Clinical Cooperation Unit Neurooncology, Bonn (Germany); Lammering, G. [MediClin Robert Janker Clinic and MVZ MediClin, Department of Radiosurgery and Stereotactic Radiotherapy, Bonn (Germany); MediClin Robert Janker Clinic, Clinical Cooperation Unit Neurooncology, Bonn (Germany); Heinrich-Heine-University of Duesseldorf, Department of Radiotherapy and Radiation Oncology, Duesseldorf (Germany)

    2014-04-15

    Recently two retrospective cohort studies report efficacy of bevacizumab in patients with recurrent atypical and anaplastic meningioma. Another successful therapeutic option of bevacizumab seems to be treatment of cerebral radiation necrosis. However, the antiangiogenic effects in MRI diffusion and perfusion in meningiomas have not been previously described in detail. The objective of this research was to evaluate the clinical and MR imaging effects of bevacizumab in a malignant meningioma patient harboring additional cerebral radiation necrosis. We report the case of an 80-year-old woman who underwent bevacizumab therapy (5 mg/kg every 2 weeks for 2 months) for treatment of a symptomatic radiation necrosis in malignant meningiomatosis of World Health Organization (WHO) grade III. The patient was closely monitored with MRI including diffusion and perfusion studies. Upon bevacizumab therapy, the clinical situation was well stabilized over a period of 4 months until the patient unfortunately died due to pneumonia/septicemia probably unrelated to bevacizumab therapy. Consecutive MRI demonstrated 4 important aspects: (1) considerable decrease of the contrast medium (CM)-enhanced radiation necrosis, (2) mixed response with respect to the meningiomatosis with stable and predominantly growing tumor lesions, (3) a new diffusion-weighted imaging (DWI) lesion in a CM-enhanced tumor as described in gliomas, which we did not interpret as a response to bevacizumab therapy, and (4) new thrombembolic infarcts, which are a known side-effect of bevacizumab treatment. Bevacizumab is effective in the treatment of radiation necrosis. We could not confirm the potential antitumor effect of bevacizumab in this patient. However, we could describe several new radiographic effects of bevacizumab therapy in malignant meningioma. (orig.) [German] In zwei aktuellen retrospektiven Kohortenstudien konnte eine Wirksamkeit von Bevacizumab bei Patienten mit rezidivierenden atypischen und

  4. Treatment satisfaction with paliperidone extended-release tablets: open-label study in schizophrenia patients dissatisfied with previous antipsychotic medication

    Directory of Open Access Journals (Sweden)

    Yang FD

    2017-04-01

    Full Text Available Fu De Yang,1 Juan Li,1 Yun Long Tan,1 Wei Ye Liang,1 Rongzhen Zhang,1 Ning Wang,1 Wei Feng,1 Shangli Cai,2 Jian Min Zhuo,2 Li Li Zhang2 1Beijing Hui-Long-Guan Hospital, 2Department of Medical Affairs, Xian Janssen Pharmaceutical Ltd, Beijing, People’s Republic of China Objective: The aim of this study was to evaluate the changes in treatment satisfaction after switching to paliperidone extended-release (ER in Chinese schizophrenia patients dissatisfied with their previous antipsychotic treatment.Methods: In this 8-week, open-label, single-arm, multicenter, prospective study, 1,693 patients dissatisfied with previous antipsychotic medication were enrolled and switched to paliperidone ER tablets (3–12 mg/d based on clinical judgment. The primary efficacy end point was change in Medication Satisfaction Questionnaire (MSQ score from baseline to week 8. The secondary end points included percentage of patients with MSQ score ≥4, as well as changes in Clinical Global Improvement-Severity (CGI-S and Personal and Social Performance (PSP scores.Results: MSQ scores increased significantly from baseline (mean [standard deviation {SD}]: 2.48 [0.55] to week 8 (5.47 [0.89], P<0.0001; primary end point, full analysis set. The percentage of patients with MSQ score ≥4 was 95.9% at week 8, indicating that most of the patients were satisfied with their treatment. Significant (P<0.0001 improvements from baseline to week 8 were noted in CGI-S score (2.37 [1.20] and PSP score (25.5 [15.0]. A total of 174 (10.28% patients experienced adverse events (AEs. The most common (>10 patients events were extrapyramidal disorder (n=84, 4.96%, poor quality sleep (n=18, 1.06% and akathisia (n=13, 0.77%. The majority of AEs were mild to moderate in severity. No deaths occurred.Conclusion: Treatment satisfaction improved after switching to paliperidone ER from the previous antipsychotic in Chinese patients with schizophrenia. Keywords: atypical antipsychotics, open label

  5. Gender differences in cerebral metabolism for color processing in mice: A PET/MRI Study.

    Science.gov (United States)

    Njemanze, Philip C; Kranz, Mathias; Amend, Mario; Hauser, Jens; Wehrl, Hans; Brust, Peter

    2017-01-01

    Color processing is a central component of mammalian vision. Gender-related differences of color processing revealed by non-invasive functional transcranial Doppler ultrasound suggested right hemisphere pattern for blue/yellow chromatic opponency by men, and a left hemisphere pattern by women. The present study measured the accumulation of [18F]fluorodeoxyglucose ([18F]FDG) in mouse brain using small animal positron emission tomography and magnetic resonance imaging (PET/MRI) with statistical parametric mapping (SPM) during light stimulation with blue and yellow filters compared to darkness condition. PET revealed a reverse pattern relative to dark condition compared to previous human studies: Male mice presented with left visual cortex dominance for blue through the right eye, while female mice presented with right visual cortex dominance for blue through the left eye. We applied statistical parametric mapping (SPM) to examine gender differences in activated architectonic areas within the orbital and medial prefrontal cortex and related cortical and sub-cortical areas that lead to the striatum, medial thalamus and other brain areas. The metabolic connectivity of the orbital and medial prefrontal cortex evoked by blue stimulation spread through a wide range of brain structures implicated in viscerosensory and visceromotor systems in the left intra-hemispheric regions in male, but in the right-to-left inter-hemispheric regions in female mice. Color functional ocular dominance plasticity was noted in the right eye in male mice but in the left eye in female mice. This study of color processing in an animal model could be applied in the study of the role of gender differences in brain disease.

  6. The MRI study of correlation between patella location and chondromalacia

    International Nuclear Information System (INIS)

    Lu Wei; Chen Shuang; Yang Jun

    2011-01-01

    Objective: To discuss the relationship between patella location and chondromalacia patella, explore its mechanism and clinical significance. Methods: Knee joint MRI was performed in 1052 patients (506 men and 546 female). Among them, there were 299 patients (100 men and 199 female) with chondromalacia patella. They were divide into the group of 1-19, the group of 20-39, the group of 40-59 years old and the group of older than 60 years to compute the positive rate respectively. Insall-Salvati method was used to measure the length of chondromalacia ligaments (L) and the length of chondromalacia path (P). The relationship between patella location and chondromalacia was tested by using t test and χ 2 test. Results: The total positive rate of chondromalacia patella was 28.4% (299/1052). In female it was 36.4% (199/546) and in men was 19.8% (100/506). The group of 1-19 years old had 16 patients (16.8%, 16/95). The group of 20-39 years old had 71 patients (17.9%, 71/396). The group of 40- 59 years old had 116 patients (33.2%, 116/349). The group of older than 60 years had 96 patients (45.3%, 96/212). The positive rate of chondromalacia patella increased with age. The L/P value of normal group and chondromalacia patella group were 1.15±0.15 and 1.24±0.17 respectively. The L/P value of normal group of men and women were 1.13±0.15 and 1.17±0.14 respectively. The L/P value of chondromalacia patella group of men and women were 1.20±0.17 and 1.26±0.16 respectively. The Insall- Salvati index of age groups showed significant differences. The L/P value of pathological changes group and normal group of 1-19 years old were 1.38±0.25 and 1.24±0.16 respectively. The L/P value of pathological changes group and normal group of 20-39 years old were 1.24±0.17 and 1.15±0.16 respectively. The L/P value of pathological changes group and normal group of 40-59 years old were 1.24±0.16 and 1.12±0.12 respectively. The L/P value of pathological changes group and normal group of older

  7. Test-retest and between-site reliability in a multicenter fMRI study.

    Science.gov (United States)

    Friedman, Lee; Stern, Hal; Brown, Gregory G; Mathalon, Daniel H; Turner, Jessica; Glover, Gary H; Gollub, Randy L; Lauriello, John; Lim, Kelvin O; Cannon, Tyrone; Greve, Douglas N; Bockholt, Henry Jeremy; Belger, Aysenil; Mueller, Bryon; Doty, Michael J; He, Jianchun; Wells, William; Smyth, Padhraic; Pieper, Steve; Kim, Seyoung; Kubicki, Marek; Vangel, Mark; Potkin, Steven G

    2008-08-01

    In the present report, estimates of test-retest and between-site reliability of fMRI assessments were produced in the context of a multicenter fMRI reliability study (FBIRN Phase 1, www.nbirn.net). Five subjects were scanned on 10 MRI scanners on two occasions. The fMRI task was a simple block design sensorimotor task. The impulse response functions to the stimulation block were derived using an FIR-deconvolution analysis with FMRISTAT. Six functionally-derived ROIs covering the visual, auditory and motor cortices, created from a prior analysis, were used. Two dependent variables were compared: percent signal change and contrast-to-noise-ratio. Reliability was assessed with intraclass correlation coefficients derived from a variance components analysis. Test-retest reliability was high, but initially, between-site reliability was low, indicating a strong contribution from site and site-by-subject variance. However, a number of factors that can markedly improve between-site reliability were uncovered, including increasing the size of the ROIs, adjusting for smoothness differences, and inclusion of additional runs. By employing multiple steps, between-site reliability for 3T scanners was increased by 123%. Dropping one site at a time and assessing reliability can be a useful method of assessing the sensitivity of the results to particular sites. These findings should provide guidance toothers on the best practices for future multicenter studies.

  8. Rehabilitative interventions and brain plasticity in autism spectrum disorders: focus on MRI-based studies

    Directory of Open Access Journals (Sweden)

    Sara eCalderoni

    2016-03-01

    Full Text Available Clinical and research evidence supports the efficacy of rehabilitative intervention for improving targeted skills or global outcomes in individuals with autism spectrum disorder (ASD. However, putative mechanisms of structural and functional brain changes are poorly understood. This review aims to investigate the research literature on the neural circuit modifications after non-pharmacological intervention. For this purpose, longitudinal studies that used magnetic resonance imaging (MRI-based techniques at the start and at the end of the trial to evaluate the neural effects of rehabilitative treatment in subjects with ASD were identified. The six included studies involved a limited number of patients in the active group (from 2 to 16, and differed by acquisition method (task-related and resting-state functional MRI as well as by functional MRI tasks. Overall, the results produced by the selected investigations demonstrated brain plasticity during the treatment interval that results in an activation/functional connectivity more similar to those of subjects with typical development. Repeated MRI evaluation may represent a promising tool for the detection of neural changes in response to treatment in patients with ASD. However, large-scale randomized controlled trials after standardized rehabilitative intervention are required before translating these preliminary results into clinical use.

  9. The Problem of Metal Needles in Acupuncture-fMRI Studies

    Directory of Open Access Journals (Sweden)

    Florian Beissner

    2011-01-01

    Full Text Available Acupuncture is a therapy based on sensory stimulation of the human body by means of metal needles. The exact underlying mechanisms of acupuncture have not been clarified so far. Functional magnetic resonance imaging (fMRI has become an important tool in acupuncture research. Standard acupuncture needles, which are made of ferromagnetic steel, however, are problematic in acupuncture-fMRI studies for several reasons, such as attraction by the scanner's magnetic field, significant image distortions and signal-dropouts, when positioned close to the head or even heating due to absorption of radio frequency (RF. The aim of this study was to compare two novel types of acupuncture needles with a standard needle for their effect on MRI image quality. The standard needle severely reduced image quality, when located inside the RF coil. The nonferromagnetic metal needle may pose a risk due to RF heating, while the plastic needle has a significantly larger diameter. In conclusion, our recommendations are: (1 standard needles should not be used in MRI; (2 Nonferromagnetic metal needles seem to be the best choice for acupoints outside of the transmitter coil; and (3 only plastic needles are suited for points inside the coil. Laser acupuncture may be a safe alternative, too.

  10. The natural history of familial cerebral cavernomas: a retrospective MRI study of 40 patients

    International Nuclear Information System (INIS)

    Labauge, P.; Laberge, S.; Brunereau, L.; Levy, C.; Houtteville, J.P.

    2000-01-01

    Our objective was to determine the natural history and prognostic factors of familial forms of cerebral cavernous malformations (CCM). Cavernomas are one of the most common central nervous system vascular malformations. Familial CCM is increasingly diagnosed, but little is known about its natural history. In a national survey, we analysed clinical and MRI features of 173 patients from 57 unrelated French families. Of these 40 had undergone at least two clinical and MRI examinations. Occurrence of haemorrhage, new lesions, change in signal intensity and size of lesions have been studied by comparison between first and last MRI studies. The CCM were classified according to Zabramski et al. Mean follow-up was 3.2 years (range 0.5-6.5 years). We followed 232 cavernomas (mean 5.9 per patient, range 1-17). Serial MRI demonstrated changes in 28 patients (70 %). Bleeding occurred in 21 lesions (9.1 %) in 14 patients (35 %). The haemorrhagic risk was 2.5 % per lesion-year, higher in type I and brain-stem CCM. We saw 23 new lesions appear in 11 patients (27.5 %), with an incidence of 0.2 lesions per patient year. Signal change was observed in 11 patients (27.5 %), in 14 lesions (6 %), while 9 lesions (3.9 %) in 9 patients (22.5 %) changed significantly in size. (orig.)

  11. Effects of Maternal Valium Administration on Fetal MRI Motion Artifact: A Comparison Study at High Altitude.

    Science.gov (United States)

    Meyers, Mariana L; Mirsky, David M; Dannull, Kimberly A; Tong, Suhong; Crombleholme, Timothy M

    2017-01-01

    Fetal MRI is performed without sedation. In cases of maternal claustrophobia or when reduction of fetal motion is critical, benzodiazepines may help. The purpose of this study was to evaluate the effects of low-dose benzodiazepine on fetal motion MRI and its effect on maternal oxygen levels at higher elevation. A total of 131 fetal MRI scans performed from March 2012 through December 2013 were studied. Nineteen of the cases were performed following Valium administration. Images were graded with a 5-point Likert scale. Using pulse oximetry, maternal oxygen levels were recorded. Results were analyzed for each category combining 3 readers' interpretations. Using a 2-sample t test model, the average imaging scores were better for the control than the Valium group (p = 0.0139). Maternal oxygen levels at different times and positions were compared using independent 2-sample t test between the Valium and control groups showing no change in O2 saturation, except when controlling for altitude and gestational age (p = 0.0326). Administration of low-dose Valium did not decrease fetal motion on MRI. Valium did not pose any risk of maternal hypoxemia, except when controlling for altitude and gestational age on supine position. Thus, caution should be exercised to prevent the risk of fetal hypoxemia. © 2016 S. Karger AG, Basel.

  12. Study on cerebral activation areas during repetition with functional MRI in normal adults

    International Nuclear Information System (INIS)

    Koseki, Yohju

    2009-01-01

    For cerebral activation of speech areas in functional MRI (f-MRI) study, the usefulness of an optical microphone, which made it possible to perform task repetition at real time during scanning, was examined. Subjects were 25 healthy adults (mean age, 27.1±5.6 years), who consisted of 15 right-handed and 10 left-handed or ambidextrous persons. Tasks comprised repetition of monosyllables, non-words, words and sentences. The repetition tasks were covertly performed during scanning of f-MRI by using an optical microphone. In both the right-handed and non-right-handed groups, activations in the left superior temporal gyrus (sensory speech area) were most frequently observed during all of the tasks. In the right-handed group, activations in the left inferior frontal (motor speech area) and superior temporal gyri were significantly more often observed than those in the right inferior frontal and superior temporal gyri. From an assessment of the laterality index (LI), left-side dominant activation was frequently seen in most of the cerebral regions including sensory and motor speech areas, although right-side and bilateral dominant activations were observed in a few cases. In both groups, activations in regions associated with sensory speech were significantly more often seen than those in regions associated with motor speech. The present predominant activations in regions involved in sensory speech indicate that the optical microphone is useful in f-MRI studies using task repetition. (author)

  13. Implicit structured sequence learning: an fMRI study of the structural mere-exposure effect.

    Science.gov (United States)

    Folia, Vasiliki; Petersson, Karl Magnus

    2014-01-01

    In this event-related fMRI study we investigated the effect of 5 days of implicit acquisition on preference classification by means of an artificial grammar learning (AGL) paradigm based on the structural mere-exposure effect and preference classification using a simple right-linear unification grammar. This allowed us to investigate implicit AGL in a proper learning design by including baseline measurements prior to grammar exposure. After 5 days of implicit acquisition, the fMRI results showed activations in a network of brain regions including the inferior frontal (centered on BA 44/45) and the medial prefrontal regions (centered on BA 8/32). Importantly, and central to this study, the inclusion of a naive preference fMRI baseline measurement allowed us to conclude that these fMRI findings were the intrinsic outcomes of the learning process itself and not a reflection of a preexisting functionality recruited during classification, independent of acquisition. Support for the implicit nature of the knowledge utilized during preference classification on day 5 come from the fact that the basal ganglia, associated with implicit procedural learning, were activated during classification, while the medial temporal lobe system, associated with explicit declarative memory, was consistently deactivated. Thus, preference classification in combination with structural mere-exposure can be used to investigate structural sequence processing (syntax) in unsupervised AGL paradigms with proper learning designs.

  14. Experimental study on quantitative evaluation of slow pulsatile flow of CSF with cine MRI

    International Nuclear Information System (INIS)

    Matsuda, Masao

    1991-01-01

    The present study was designed to evaluate the slow pulsatile flow of cerebrospinal fluid (CSF) quantitatively with cine MRI in phantom experiment for the clinical application. The flow phantom was constructed from a plastic tube with a narrow channel to represent the central aqueduct. The phantom was filled with water to represent the CSF. The second tube filled with stationary water was positioned beside the flow phantom and acted as a control for no-flow signal strength. The ratio of signal intensity in regions of interest for the flow phantom and the control was measured. Not only the actual velocity curve of the flowing water through the phantom but also the temporal profile of signal intensity showed two main peaks with other small peaks in one cycle. This suggested a close relationship between signal intensity of cine MRI and flow velocity. A significant correlation between the signal intensity ratio and the velocity was obtained on cine MRI pulse sequences. Cine MRI was thus found to have the ability to give quantitative information about slow pulsatile flow. The most suitable pulse sequence was fast imaging with steady state free precession pulse sequence at the flip angle between 50 and 90 degrees. This preliminary study suggests that the slow pulsatile flow of CSF passing along the aqueduct can be visualized and measured. Thus, the sequence proposed has a potential for the investigation of normal and disturbed CSF circulation and the mapping of the flow pattern in different pathological conditions. (N.K.)

  15. Contactless Abdominal Fat Reduction With Selective RF™ Evaluated by Magnetic Resonance Imaging (MRI): Case Study.

    Science.gov (United States)

    Downie, Jeanine; Kaspar, Miroslav

    2016-04-01

    Noninvasive body shaping methods seem to be an ascending part of the aesthetics market. As a result, the pressure to develop reliable methods for the collection and presentation of their results has also increased. The most used techniques currently include ultrasound measurements of fat thickness in the treated area, caliper measurements, bioimpedance-based scale measurements or circumferential tape measurements. Although these are the most used techniques, almost all of them have some limitations in reproducibility and/or accuracy. This study shows Magnetic Resonance Imaging (MRI) as the new method for the presentation of results in the body shaping industry. Six subjects were treated by a contactless selective radiofrequency device (BTL Vanquish ME, BTL Industries Inc., Boston, MA). The MRI fat thickness was measured at the baseline and at 4-weeks following the treatment. In addition to MRI images and measurements, digital photographs and anthropometric evaluations such as weight, abdominal circumference, and caliper fat thickness measurements were recorded. Abdominal fat thickness measurements from the MRI were performed from the same slices determined by the same tissue artefacts. The MRI fat thickness difference between the baseline measurement and follow up visit showed an average reduction of 5.36 mm as calculated from the data of 5 subjects. One subject dropped out of study due to non-study related issues. The results were statistically significant based on the Student's T-test evaluation. Magnetic resonance imaging abdominal fat thickness measurements seems to be the best method for the evaluation of fat thickness reduction after non-invasive body shaping treatments. In this study, this method shows average fat thickness reduction of 5.36 mm while the weight of the subjects didn't change significantly. A large spot size measuring 1317 cm(2) (204 square inches) covers the abdomen flank to flank. The average thickness of 5.36 mm of the fat layer reduced

  16. SU-G-JeP2-14: MRI-Based HDR Prostate Brachytherapy: A Phantom Study for Interstitial Catheter Reconstruction with 0.35T MRI Images

    International Nuclear Information System (INIS)

    Park, S; Kamrava, M; Yang, Y

    2016-01-01

    Purpose: To evaluate the accuracy of interstitial catheter reconstruction with 0.35T MRI images for MRI-based HDR prostate brachytherapy. Methods: Recently, a real-time MRI-guided radiotherapy system combining a 0.35T MRI system and three cobalt 60 heads (MRIdian System, ViewRay, Cleveland, OH, USA) was installed in our department. A TrueFISP sequence for MRI acquisition at lower field on Viewray was chosen due to its fast speed and high signal-to-noise efficiency. Interstitial FlexiGuide needles were implanted into a tissue equivalent ultrasound prostate phantom (CIRS, Norfolk, Virginia, USA). After an initial 15s pilot MRI to confirm the location of the phantom, planning MRI was acquired with a 172s TrueFISP sequence. The pulse sequence parameters included: flip angle = 60 degree, echo time (TE) =1.45 ms, repetition time (TR) = 3.37 ms, slice thickness = 1.5 mm, field of view (FOV) =500 × 450mm. For a reference image, a CT scan was followed. The CT and MR scans were then fused with the MIM Maestro (MIM software Inc., Cleveland, OH, USA) and sent to the Oncentra Brachy planning system (Elekta, Veenendaal, Netherlands). Automatic catheter reconstruction using CT and MR image intensities followed by manual reconstruction was used to digitize catheters. The accuracy of catheter reconstruction was evaluated from the catheter tip location. Results: The average difference between the catheter tip locations reconstructed from the CT and MR in the transverse, anteroposterior, and craniocaudal directions was −0.1 ± 0.1 mm (left), 0.2 ± 0.2 mm (anterior), and −2.3 ± 0.5 mm (cranio). The average distance in 3D was 2.3 mm ± 0.5 mm. Conclusion: This feasibility study proved that interstitial catheters can be reconstructed with 0.35T MRI images. For more accurate catheter reconstruction which can affect final dose distribution, a systematic shift should be applied to the MR based catheter reconstruction in HDR prostate brachytherapy.

  17. Relational complexity modulates activity in the prefrontal cortex during numerical inductive reasoning: an fMRI study.

    Science.gov (United States)

    Feng, Xiao; Peng, Li; Chang-Quan, Long; Yi, Lei; Hong, Li

    2014-09-01

    Most previous studies investigating relational reasoning have used visuo-spatial materials. This fMRI study aimed to determine how relational complexity affects brain activity during inductive reasoning, using numerical materials. Three numerical relational levels of the number series completion task were adopted for use: 0-relational (e.g., "23 23 23"), 1-relational ("32 30 28") and 2-relational ("12 13 15") problems. The fMRI results revealed that the bilateral dorsolateral prefrontal cortex (DLPFC) showed enhanced activity associated with relational complexity. Bilateral inferior parietal lobule (IPL) activity was greater during the 1- and 2-relational level problems than during the 0-relational level problems. In addition, the left fronto-polar cortex (FPC) showed selective activity during the 2-relational level problems. The bilateral DLPFC may be involved in the process of hypothesis generation, whereas the bilateral IPL may be sensitive to calculation demands. Moreover, the sensitivity of the left FPC to the multiple relational problems may be related to the integration of numerical relations. The present study extends our knowledge of the prefrontal activity pattern underlying numerical relational processing. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Value and reliability of findings from previous epidemiologic studies in the assessment of radiation-related cancer risks. Pt. 3

    International Nuclear Information System (INIS)

    Frasch, G.; Martignoni, K.

    1990-01-01

    The theories put forward here are predominantly based on pooled data from previous studies in a number of cohorts made up by mostly non-average individuals. These studies were carried out by various researchers and differed in procedures and aims. Factors of major importance to the validity and reliability of the conclusions drawn from this study are pointed out. In one chapter some light is thrown on factors known to bear a relation to the incidence of radiation-induced cancer of the breast, even though at present this can only very vaguely be described on a quantitative basis. These factors include fractionated dose regimens, pregnancies and parturitions, menarche, menopause, synergisms as well as secondary cancer of the breast. The available body of evidence suggests that exposure of each of 1 million women to a dose of 10 mGy (rad) can be linked with approx. 3 additional cases of mammary cancer reported on an average per year after the latency period. The fact that there is some statistical scatter around this value is chiefly attributable to age-related causes at the beginning of exposure. Differences in ethnic and cultural characteristics between the populations investigated appeared to be less important here. (orig./MG) [de

  19. Barriers to postpartum screening for type 2 diabetes: a qualitative study of women with previous gestational diabetes.

    Science.gov (United States)

    Rafii, Forough; Rahimparvar, Seyedeh Fatemeh Vasegh; Mehrdad, Neda; Keramat, Afsaneh

    2017-01-01

    Risk of developing type 2 diabetes is increased in women with previous gestational diabetes mellitus (GDM). Postpartum glycemic screening is recommended in women with recent GDM. But this screening rate is low and the reasons are unclear. The aim of this study was to explore the experiences of Iranian women with recent GDM on barriers of postpartum screening for diabetes. This qualitative study was conducted in Tehran, Iran in 2016. Semi-structured interview was used for data collection. 22 women with recent GDM were interviewed. These women gave birth in Tehran hospitals at a minimum of 6 months before interview. The missed screening defined as not attending to laboratory for Fasting Blood Sugar and/or Oral Glucose Tolerance Test, 6 week to 6 month after their child birthing. The data was analyzed by content analysis method. Themes and sub-themes that illustrated the barriers to postpartum diabetes screening were: inadequate education (about developing diabetes in the future, implementation of the screening, and glucometer validity in diagnosis of diabetes), perceiving the screening as difficult (feeling comfortable with the glucometer, poor laboratory conditions, issues related to the baby/babies, and financial problems), improper attitudes toward the screening (unwilling to get diagnosed, not giving priority to oneself, having false beliefs) and procrastination (gap to intention and action, self-deception and self-regulation failure). Women with recent GDM reported several barriers for postpartum diabetes screening. This study help to develop the evidence-based interventions for improving this screening rate.

  20. A Flexible-Dose Study of Paliperidone ER in Patients With Nonacute Schizophrenia Previously Treated Unsuccessfully With Oral Olanzapine.

    Science.gov (United States)

    Kotler, Moshe; Dilbaz, Nesrin; Rosa, Fernanda; Paterakis, Periklis; Milanova, Vihra; Smulevich, Anatoly B; Lahaye, Marjolein; Schreiner, Andreas

    2016-01-01

    The goal of this study was to explore the tolerability, safety, and treatment response of switching from oral olanzapine to paliperidone extended release (ER). Adult patients with nonacute schizophrenia who had been treated unsuccessfully with oral olanzapine were switched to flexible doses of paliperidone ER (3 to 12 mg/d). The primary efficacy outcome was a ≥ 20% improvement in Positive and Negative Syndrome Scale (PANSS) total scores from baseline to endpoint for patients who switched medications because of lack of efficacy with olanzapine and noninferiority versus previous olanzapine treatment (mean endpoint change in PANSS total scores vs. baseline of ≤ 5 points) for patients who switched for reasons other than lack of efficacy. Safety and tolerability were assessed by monitoring adverse events, extrapyramidal symptoms, and weight change. Of 396 patients, 65.2% were men, mean age was 40.0 ± 12.0 years, and 75.5% had paranoid schizophrenia. Among the patients whose main reason for switching was lack of efficacy, an improvement in the PANSS total score of ≥ 20% occurred in 57.4% of patients. Noninferiority was confirmed for each subgroup of patients whose main reason for switching was something other than lack of efficacy. Paliperidone ER was generally well tolerated. Extrapyramidal symptoms as measured by total Extrapyramidal Symptom Rating Scale scores showed statistically significant and clinically relevant improvements at endpoint, the average weight decreased by 0.8 ± 5.2 kg at endpoint, and a clinically relevant weight gain of ≥ 7% occurred in 8.0% of patients. Paliperidone ER flexibly-dosed over 6 months was well tolerated and associated with a meaningful clinical response in patients with nonacute schizophrenia who had previously been unsuccessfully treated with oral olanzapine.

  1. Functional MRI in pre-surgical planning: Case study and cautionary notes

    Directory of Open Access Journals (Sweden)

    Bruce S Spottiswoode

    2012-09-01

    Full Text Available Background. Since its inception almost 20 years ago, functional magnetic resonance imaging (fMRI has greatly advanced our knowledge of human brain function. Although the clinical applications of fMRI are still limited, there have recently been encouraging advances for its use in pre-operative functional cortical mapping to identify potentially eloquent areas prior to neurosurgery. Objectives. We explore the potential use of this emerging technique by presenting a neurosurgical case study, as performed at the Cape Universities Brain Imaging Centre (CUBIC, Tygerberg, Cape Town. We conclude with a brief summary of the potential pitfalls of this technique, as well as cautionary guidelines based on our experience. Methods and results. A 22-year-old male patient from Tygerberg Hospital underwent the successful resection of an anaplastic astrocytoma after fMRI presurgical planning at our facility. The subject was able to leave the ward unassisted. Conclusion. If consideration is given to the many limitations of this emerging technique, fMRI can be useful in aiding the neurosurgeon in pre-operative planning of his surgical approach.

  2. MRI-guided percutaneous retrograde drilling of osteochondritis dissecans of the talus: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Kerimaa, Pekka; Ojala, Risto; Markkanen, Paula; Tervonen, Osmo; Blanco Sequeiros, Roberto [Oulu University Hospital, Department of Radiology, Oulu (Finland); Sinikumpu, Juha-Jaakko; Korhonen, Jussi [Oulu University Hospital, Department of Paediatric Surgery, Oulu (Finland); Hyvoenen, Pekka [Oulu University Hospital, Department of Surgery, Oulu (Finland)

    2014-07-15

    The purpose of this study was to evaluate the feasibility of MRI guidance for percutaneous retrograde drilling in the treatment of osteochondritis dissecans of the talus (OCDT). Four patients, one juvenile and three adults, with one OCDT lesion each and persisting ankle pain after conservative treatment, were treated with MRI-guided retrograde drilling. All lesions were stable and located in the middle or posterior medial third of the talar dome. Pain relief and the ability to return to normal activities were assessed during clinical follow-up. MRI and plain film radiographs were used for imaging follow-up. Technical success was 100 % with no complications and with no damage to the overlying cartilage. All patients experienced some clinical benefit, although only one had complete resolution of pain and one had a relapse leading to surgical treatment. Changes in the pathological imaging findings were mostly very slight during the follow-up period. MRI guidance seems accurate, safe and technically feasible for retrograde drilling of OCDT. Larger series are needed to reliably assess its clinical value. (orig.)

  3. Merosin-deficient congenital muscular dystrophy (CMD): a study of 25 Brazilian patients using MRI

    International Nuclear Information System (INIS)

    Leite, Claudia C.; Lucato, Leandro T.; Martin, Maria G.M.; Ferreira, Lucio G.; Resende, Maria B.D.; Carvalho, Mary S.; Marie, Suely K.N.; Reed, Umbertina C.; Jinkins, J.Randy

    2005-01-01

    Merosin-deficient congenital muscular dystrophy (CMD) is characterized clinically by hypotonia and muscular weakness and, on imaging studies, by white matter (WM) abnormality. To evaluate MRI findings in Brazilian patients with merosin-deficient CMD. Twenty-five patients were evaluated using MRI. Three patients presented with partial merosin deficiency and 22 with total merosin deficiency. Follow-up examinations were done in 7 cases. T1- and T2-weighted images were performed in all examinations, and fluid-attenuated inversion recovery (FLAIR) was performed in 15. Enhanced images were done in 11 cases. The WM involvement was classified according to location and severity. From 1991 to 2004, 32 MRI examinations were performed. Severe involvement was found in 23 patients in the frontal and temporal lobes, in 18 patients in the parietal lobes, and in 7 patients in the occipital lobes. The brain stem (n=5), cerebellum (n=6), internal capsules (n=1), and external capsules (n=5) were also affected. One patient had occipital pachygyria, and one had cerebellar vermian hypoplasia. No gadolinium enhancement was noted. Follow-up MRI showed no interval change (n=4), progression (n=1), or improvement of the findings (n=2). (orig.)

  4. Fundamental Tongue Motions for Trumpet Playing: A Study Using Cine Magnetic Resonance Imaging (Cine MRI).

    Science.gov (United States)

    Furuhashi, Hiroko; Chikui, Toru; Inadomi, Daisuke; Shiraishi, Tomoko; Yoshiura, Kazunori

    2017-12-01

    Though the motions of structures outside the mouth in trumpet performance have been reported, the dynamics of intraoral structures remain unelucidated. This study explored the tongue's movement in trumpet playing using cine magnetic resonance imaging (cine MRI) and demonstrated the effects of intraoral anatomical structures on changes in pitch and dynamics. Cine MRI was applied to 18 trumpet players, who were divided into two groups (7 beginner, 11 advanced) based on their ability to play a certain high note. They were instructed to play a custom-made MRI-compatible simulated trumpet. Pitch-change tasks and dynamics-change tasks were assigned. The positions of the anatomical points and intraoral areas were identified on outlined images, and the changes associated with each task were evaluated. A forward and upward projection of the tongue was observed in the production of higher pitches, and there were no significant differences in all areas. In louder dynamics, a backward and downward bending of the tongue occurred, the tongue area became smaller (pcine MRI that certain tongue movements were associated with each task. Tongue protrusion in the production of higher pitch and bending in louder dynamics can be rationalized using acoustics theory and the movements of anatomical structures. These findings seem to be consistent regardless of the player's proficiency.

  5. Motor function deficits in schizophrenia: an fMRI and VBM study

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Sadhana; Modi, Shilpi; Kumar, Pawan; Singh, Namita; Khushu, Subash [Institute of Nuclear Medicine and Allied Sciences (INMAS), NMR Research Center, Delhi (India); Goyal, Satnam; Bhatia, Triptish; Deshpande, Smita N. [RML Hospital, PGIMER, New Delhi (India)

    2014-05-15

    To investigate whether the motor functional alterations in schizophrenia (SZ) are also associated with structural changes in the related brain areas using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). A sample of 14 right-handed SZ patients and 14 right-handed healthy control subjects matched for age, sex, and education were examined with structural high-resolution T1-weighted MRI; fMRI images were obtained during right index finger-tapping task in the same session. fMRI results showed reduced functional activation in the motor areas (contralateral precentral and postcentral gyrus) and ipsilateral cerebellum in SZ subjects as compared to healthy controls (n = 14). VBM analysis also revealed reduced grey matter in motor areas and white matter reduction in cerebellum of SZ subjects as compared to controls. The present study provides an evidence for a possible association between structural alterations in the motor cortex and disturbed functional activation in the motor areas in persons affected with SZ during a simple finger-tapping task. (orig.)

  6. Motor function deficits in schizophrenia: an fMRI and VBM study

    International Nuclear Information System (INIS)

    Singh, Sadhana; Modi, Shilpi; Kumar, Pawan; Singh, Namita; Khushu, Subash; Goyal, Satnam; Bhatia, Triptish; Deshpande, Smita N.

    2014-01-01

    To investigate whether the motor functional alterations in schizophrenia (SZ) are also associated with structural changes in the related brain areas using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). A sample of 14 right-handed SZ patients and 14 right-handed healthy control subjects matched for age, sex, and education were examined with structural high-resolution T1-weighted MRI; fMRI images were obtained during right index finger-tapping task in the same session. fMRI results showed reduced functional activation in the motor areas (contralateral precentral and postcentral gyrus) and ipsilateral cerebellum in SZ subjects as compared to healthy controls (n = 14). VBM analysis also revealed reduced grey matter in motor areas and white matter reduction in cerebellum of SZ subjects as compared to controls. The present study provides an evidence for a possible association between structural alterations in the motor cortex and disturbed functional activation in the motor areas in persons affected with SZ during a simple finger-tapping task. (orig.)

  7. MRI-guided percutaneous retrograde drilling of osteochondritis dissecans of the talus: a feasibility study

    International Nuclear Information System (INIS)

    Kerimaa, Pekka; Ojala, Risto; Markkanen, Paula; Tervonen, Osmo; Blanco Sequeiros, Roberto; Sinikumpu, Juha-Jaakko; Korhonen, Jussi; Hyvoenen, Pekka

    2014-01-01

    The purpose of this study was to evaluate the feasibility of MRI guidance for percutaneous retrograde drilling in the treatment of osteochondritis dissecans of the talus (OCDT). Four patients, one juvenile and three adults, with one OCDT lesion each and persisting ankle pain after conservative treatment, were treated with MRI-guided retrograde drilling. All lesions were stable and located in the middle or posterior medial third of the talar dome. Pain relief and the ability to return to normal activities were assessed during clinical follow-up. MRI and plain film radiographs were used for imaging follow-up. Technical success was 100 % with no complications and with no damage to the overlying cartilage. All patients experienced some clinical benefit, although only one had complete resolution of pain and one had a relapse leading to surgical treatment. Changes in the pathological imaging findings were mostly very slight during the follow-up period. MRI guidance seems accurate, safe and technically feasible for retrograde drilling of OCDT. Larger series are needed to reliably assess its clinical value. (orig.)

  8. Regional homogeneity changes in prelingually deafened patients: a resting-state fMRI study

    Science.gov (United States)

    Li, Wenjing; He, Huiguang; Xian, Junfang; Lv, Bin; Li, Meng; Li, Yong; Liu, Zhaohui; Wang, Zhenchang

    2010-03-01

    Resting-state functional magnetic resonance imaging (fMRI) is a technique that measures the intrinsic function of brain and has some advantages over task-induced fMRI. Regional homogeneity (ReHo) assesses the similarity of the time series of a given voxel with its nearest neighbors on a voxel-by-voxel basis, which reflects the temporal homogeneity of the regional BOLD signal. In the present study, we used the resting state fMRI data to investigate the ReHo changes of the whole brain in the prelingually deafened patients relative to normal controls. 18 deaf patients and 22 healthy subjects were scanned. Kendall's coefficient of concordance (KCC) was calculated to measure the degree of regional coherence of fMRI time courses. We found that regional coherence significantly decreased in the left frontal lobe, bilateral temporal lobes and right thalamus, and increased in the postcentral gyrus, cingulate gyrus, left temporal lobe, left thalamus and cerebellum in deaf patients compared with controls. These results show that the prelingually deafened patients have higher degree of regional coherence in the paleocortex, and lower degree in neocortex. Since neocortex plays an important role in the development of auditory, these evidences may suggest that the deaf persons reorganize the paleocortex to offset the loss of auditory.

  9. Morel-Lavallée Lesions of the Knee: MRI Findings Compared With Cadaveric Study Findings.

    Science.gov (United States)

    Vassalou, Evangelia E; Zibis, Aristeidis H; Raoulis, Vasileios A; Tsifountoudis, Ioannis P; Karantanas, Apostolos H

    2018-05-01

    The purpose of this study is to describe the MRI findings and treatment decisions and outcome for Morel-Lavallée lesions (MLLs) of the knee and to investigate whether evidence exists to support an increased frequency of such lesions on the medial or lateral side by performing a cadaveric experiment. In a 4-year period, 24 MRI studies of 24 consecutive patients (16 male patients and eight female patients) with knee MLLs were retrospectively reviewed. Patient demographic characteristics, treatment decisions and outcome, and associated injuries were recorded. The location of the MLL was categorized as medial, lateral, or global. Lesions were categorized according to an established MRI classification. During the cadaveric experiment, the compartmental pressures of the medial or lateral aspect of the knee were monitored in 20 cadaveric knees. The chi-square test, t test, and Pearson correlation were used for statistical analysis. MLLs were located medially in 16 patients, laterally in two patients, and globally in six patients. The medial location was significantly more common than a lateral or global location (p < 0.05). MLLs were classified as type I in 14 patients, type II in eight patients, and type III in two patients. MRI type was correlated with the chronicity of injury (r 2 = 0.614; p = 0.0014). Fractures were the most common associated injuries, occurring in seven of 24 patients. In 17 patients, all of whom had conservatively treated type I or type II lesions, complete resolution of the MLL occurred. The maximum compartmental pressures were significantly higher on the lateral side than on the medial side (p < 0.0001). Knee MLLs have a predilection for the medial side, which may be attributed to the lower resistance in this location, and they have variable patterns on MRI, which correlate with chronicity. Conservative treatment of type I and II lesions seems effective.

  10. Impact of magnetic field strength and receiver coil in ocular MRI: a phantom and patient study.

    Science.gov (United States)

    Erb-Eigner, K; Warmuth, C; Taupitz, M; Willerding, G; Bertelmann, E; Asbach, P

    2013-09-01

    Generally, high-resolution MRI of the eye is performed with small loop surface coils. The purpose of this phantom and patient study was to investigate the influence of magnetic field strength and receiver coils on image quality in ocular MRI. The eyeball and the complex geometry of the facial bone were simulated by a skull phantom with swine eyes. MR images were acquired with two small loop surface coils with diameters of 4 cm and 7 cm and with a multi-channel head coil at 1.5 and 3 Tesla, respectively. Furthermore, MRI of the eye was performed prospectively in 20 patients at 1.5 Tesla (7 cm loop surface coil) and 3 Tesla (head coil). These images were analysed qualitatively and quantitatively and statistical significance was tested using the Wilcoxon-signed-rank test (a p-value of less than 0.05 was considered to indicate statistical significance). The analysis of the phantom images yielded the highest mean signal-to-noise ratio (SNR) at 3 Tesla with the use of the 4 cm loop surface coil. In the phantom experiment as well as in the patient studies the SNR was higher at 1.5 Tesla by applying the 7 cm surface coil than at 3 Tesla by applying the head coil. Concerning the delineation of anatomic structures no statistically significant differences were found. Our results show that the influence of small loop surface coils on image quality (expressed in SNR) in ocular MRI is higher than the influence of the magnetic field strength. The similar visibility of detailed anatomy leads to the conclusion that the image quality of ocular MRI at 3 Tesla remains acceptable by applying the head coil as a receiver coil. © Georg Thieme Verlag KG Stuttgart · New York.

  11. Population-based imaging and radiomics. Rational and perspective of the German National Cohort MRI study

    International Nuclear Information System (INIS)

    Schlett, C.L.; Weckbach, S.; Hendel, T.

    2016-01-01

    The MRI study within the German National Cohort, a large-scale, population-based, longitudinal study in Germany, comprises comprehensive characterization and phenotyping of a total of 30 000 participants using 3-Tesla whole-body MR imaging. A multi-centric study design was established together with dedicated core facilities for e.g. managing incidental findings or providing quality assurance. As such, the study represents a unique opportunity to substantially impact imaging-based risk stratification leading to personalized and precision medicine. Supported by the developments in the field of computational science, the newly developing scientific field of radiomics has large potential for the future. In the present article we provide an overview on population-based imaging and Radiomics and conceptualize the rationale and design of the MRI study within the German National Cohort.

  12. Specificity of aesthetic experience for artworks: an fMRI study

    Directory of Open Access Journals (Sweden)

    Cinzia eDi Dio

    2011-11-01

    Full Text Available In a previous study aimed at investigating the neural correlates of aesthetic experience in the beholder we found that observation of canonical sculptures, relative to sculptures whose proportions had been modified, produced the activation of a specific brain network. This network included various cortical areas and, most interestingly, the right anterior insula. We interpreted this latter activation as the neural signature underpinning emotion-related responses during aesthetic experience. In the present fMRI study, we investigated whether aesthetic experience for Classical sculptures has a quality of its own, distinct from that underpinning observation of real human bodies. Sculpture images and pictures of young athletes, matched to sculptures for body postures and proportions, were used as stimuli. Participants were students naïve to art criticism. Results showed a similar activation pattern for the two stimulus-categories. Direct comparisons between stimulus-categories highlighted, however, some relevant differences. Observation of sculptures, relative to real human body images, determined a greater activation of some visual areas, including fusiform gyrus, plus the right anterior insula. The opposite contrast showed a stronger activation of the superior temporal sulcus. Moreover, canonical proportion in sculpture, but not in human body images, produced a stronger activation of the right anterior insula with respect to proportion-modified images. These data show that, during observation of sculpture images, attention is more attracted by specific visual aspects of the stimulus, whereas observation of real human body images activates areas encoding biological movement. Most interestingly, sculptures elicited activations in right anterior insula, which we suggested to be crucial in hallmarking emotional responses during aesthetic experience. This pattern was poorly expressed during observation of human bodies, suggesting poverty of true

  13. Study of diffusion weighted MRI as a predictive biomarker of response during radiotherapy for high and intermediate risk squamous cell cancer of the oropharynx: The MeRInO study

    Directory of Open Access Journals (Sweden)

    C Paterson

    2017-02-01

    Discussion: The use of DW-MRI as a predictive biomarker during RT for SCC H&N is in its infancy but studies to date have found that response to treatment may indeed be predicted by comparison of DW-MRI carried out before and during treatment. However, previous studies have included all sub-sites and biological sub-types. Establishing ADC thresholds that predict for local failure is an essential step towards using DW-MRI to improve the therapeutic ratio in treating SCC H&N. This would be done most robustly in a specific H&N sub-site and in sub-types with similar biological behaviour. The MeRInO study will help establish these thresholds in OPSCC.

  14. The effects of background noise on dichotic listening to consonant-vowel syllables: An fMRI study.

    Science.gov (United States)

    Dos Santos Sequeira, Sarah; Specht, Karsten; Moosmann, Matthias; Westerhausen, Rene; Hugdahl, Kenneth

    2010-11-01

    The present fMRI study attempts to identify brain areas that may underlie the effect of different background noises on functional brain asymmetry in a dichotic listening task. Previous studies have shown that the prominent right ear advantage in dichotic listening to consonant-vowel syllables is affected by background noise. To explore the underlying neuronal processes, haemodynamic brain responses using fMRI were recorded while participants performed the dichotic listening task in two different noisy backgrounds (conversational "babble" and traffic noise). The behavioural results showed a reduction of the right ear advantage in the background noise conditions, especially in the traffic noise condition. The behavioural results are discussed in terms of alertness-attentional mechanisms. The effects of background noise on brain activation involved significant activations in a speech-processing network. Specifically the changes in activations in the peri-Sylvian region of the superior temporal gyrus and in the temporo-parietal junction part in the left hemisphere, as well as in the superior temporal gyrus/sulcus area in the right hemisphere may mirror the effects of noise on behavioural performance. The effects of noise on brain activation are discussed with regard to pre-activation mechanisms.

  15. Degenerative joint disease on MRI and physical activity: a clinical study of the knee joint in 320 patients

    International Nuclear Information System (INIS)

    Bachmann, G.F.; Rauber, K.; Damian, M.S.; Rau, W.S.; Basad, E.

    1999-01-01

    We examined 320 patients with MRI and arthroscopy after an acute trauma to evaluate MRI in diagnosis of degenerative joint disease of the knee in relation to sports activity and clinical data. Lesions of cartilage and menisci on MRI were registered by two radiologists in consensus without knowledge of arthroscopy. Arthroscopy demonstrated grade-1 to grade-4 lesions of cartilage on 729 of 1920 joint surfaces of 320 knees, and MRI diagnosed 14 % of grade-1, 32 % of grade-2, 94 % of grade-3, and 100 % of grade-4 lesions. Arthroscopy explored 1280 meniscal areas and showed degenerations in 10 %, tears in 11.4 %, and complex lesions in 9.2 %. Magnetic resonance imaging was in agreement with arthroscopy in 81 % showing more degenerations but less tears of menisci than arthroscopy. Using a global system for grading the total damage of the knee joint into none, mild, moderate, or severe changes, agreement between arthroscopy and MRI was found in 82 %. Magnetic resonance imaging and arthroscopy showed coherently that degree of degenerative joint changes was significantly correlated to patient age or previous knee trauma. Patients over 40 years had moderate to severe changes on MRI in 45 % and patients under 30 years in only 22 %. Knee joints with a history of trauma without complete structural or functional reconstitution showed marked changes on MRI in 57 %, whereas stable joints without such alterations had degenerative changes in only 26 %. There was no correlation of degenerative disease to gender, weight, type, frequency, and intensity of sports activity. Therefore, MRI is an effective non-invasive imaging method for exact localization and quantification of chronic joint changes of cartilage and menisci that recommends MRI for monitoring in sports medicine. (orig.) (orig.)

  16. EKG-based detection of deep brain stimulation in fMRI studies.

    Science.gov (United States)

    Fiveland, Eric; Madhavan, Radhika; Prusik, Julia; Linton, Renee; Dimarzio, Marisa; Ashe, Jeffrey; Pilitsis, Julie; Hancu, Ileana

    2018-04-01

    To assess the impact of synchronization errors between the assumed functional MRI paradigm timing and the deep brain stimulation (DBS) on/off cycling using a custom electrocardiogram-based triggering system METHODS: A detector for measuring and predicting the on/off state of cycling deep brain stimulation was developed and tested in six patients in office visits. Three-electrode electrocardiogram measurements, amplified by a commercial bio-amplifier, were used as input for a custom electronics box (e-box). The e-box transformed the deep brain stimulation waveforms into transistor-transistor logic pulses, recorded their timing, and propagated it in time. The e-box was used to trigger task-based deep brain stimulation functional MRI scans in 5 additional subjects; the impact of timing accuracy on t-test values was investigated in a simulation study using the functional MRI data. Following locking to each patient's individual waveform, the e-box was shown to predict stimulation onset with an average absolute error of 112 ± 148 ms, 30 min after disconnecting from the patients. The subsecond accuracy of the e-box in predicting timing onset is more than adequate for our slow varying, 30-/30-s on/off stimulation paradigm. Conversely, the experimental deep brain stimulation onset prediction accuracy in the absence of the e-box, which could be off by as much as 4 to 6 s, could significantly decrease activation strength. Using this detector, stimulation can be accurately synchronized to functional MRI acquisitions, without adding any additional hardware in the MRI environment. Magn Reson Med 79:2432-2439, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  17. How Does Your Brain See “Living” Circles: A Study of Animacy and Intention Using fMRI

    Directory of Open Access Journals (Sweden)

    P McAleer

    2011-04-01

    Full Text Available It is widely reported that the perception of animacy can occur from simple displays of moving shapes with participants attributing such qualities as goals, beliefs, and intentions. Furthermore, via neuroimaging studies, a network of brain areas, including regions of the temporal and frontal lobes, has been shown to process the percept. However, problems exist that prevent the bridging of fMRI studies on the perception of animacy and intention in shapes to the same percept of human movement. First, the issue of prior displays being poorly controlled in terms of low-level visual cues blurs the actual root of the effect. Second, the general use of synthetically generated displays and their relationship to actual human movement: a problem previously addressed in behavioural studies via a systematic reduction of live visual footage of human actors. Therefore, we propose experiments that incorporate both synthetically generated animacy stimuli and displays derived from human motion. Following the classic Tremoulet and Feldman displays, stimuli are created that allow for manipulation of animacy and intent whilst controlling low-level visual cues. These displays are then used in a whole-brain fMRI study to locate neural regions sensitive to the perception of animacy and intention. Finally, within these regions, a region-of-interest analysis is performed to examine the change in brain activation from viewing animacy displays derived from human movement with varying intent (eg, chasing or following. This study develops the relationship between previous animacy literature and the real-world perception of intent.

  18. Amplitude of low-frequency fluctuation (ALFF) and fractional ALFF in migraine patients: a resting-state functional MRI study

    International Nuclear Information System (INIS)

    Wang, J.-J.; Chen, X.; Sah, S.K.; Zeng, C.; Li, Y.-M.; Li, N.; Liu, M.-Q.; Du, S.-I.

    2016-01-01

    Aim: To evaluate the amplitude of low-frequency oscillations (LFOs) of the brain in migraine patients using amplitude of low-frequency fluctuation (ALFF) and fractional ALFF in the interictal period, in comparison to healthy controls (HCs). Materials and methods: A total of 54 subjects, including 30 migraineurs and 24 gender- and age-matched HCs completed the fMRI. All the data and ALFF, fALFF analyses were preprocessed with the Data Processing Assistant for Resting-State fMRI (DPARSF). All of the statistical analyses were performed using the REST software to explore the differences in ALFF and fALFF between migraine patients and HCs. Results: In contrast to HCs, migraine patients showed significant ALFF increase in the left medulla and pons, the bilateral cerebellum posterior lobe and right insula. The regions showing decreased ALFF in migraine patients included the bilateral cerebellum posterior lobe, left cerebellum anterior lobe, bilateral orbital cortex, right middle frontal gyrus, bilateral occipital lobe, right fusiform gyrus, and bilateral postcentral gyrus. The fALFFs in migraine patients were significantly increased in the bilateral insular and left orbital cortex, but were decreased in the left occipital lobe and bilateral cerebellum posterior lobe. Conclusion: These ALFF and fALFF alterations in the brain regions of migraineurs are in keeping with the domains associated with pain and cognition. Such brain functional alteration may contribute to further understanding of migraine-related network imbalances demonstrated in previous studies. - Highlights: • Migraine is a common, paroxysmal, highly disabling primary headache disorder. • Resting-state fMRI offers a novel approach to measure spontaneous brain activity in migraine patients • The ALFF and fALFF alterations in migraineurs' brain regions are in keeping with the domains associated with pain and cognition.

  19. Pilot Study of an Individualised Early Postpartum Intervention to Increase Physical Activity in Women with Previous Gestational Diabetes

    Directory of Open Access Journals (Sweden)

    Harold David McIntyre

    2012-01-01

    Full Text Available Optimal strategies to prevent progression towards overt diabetes in women with recent gestational diabetes remain ill defined. We report a pilot study of a convenient, home based exercise program with telephone support, suited to the early post-partum period. Twenty eight women with recent gestational diabetes were enrolled at six weeks post-partum into a 12 week randomised controlled trial of Usual Care (n=13 versus Supported Care (individualised exercise program with regular telephone support; n=15. Baseline characteristics (Mean ± SD were: Age  33±4  years; Weight 80 ± 20 kg and Body Mass Index (BMI 30.0±9.7 kg/m2. The primary outcome, planned physical activity {Median (Range}, increased by 60 (0–540 mins/week in the SC group versus 0 (0–580 mins/week in the UC group (P=0.234. Walking was the predominant physical activity. Body weight, BMI, waist circumference, % body fat, fasting glucose and insulin did not change significantly over time in either group. This intervention designed to increase physical activity in post-partum women with previous gestational diabetes proved feasible. However, no measurable improvement in metabolic or biometric parameters was observed over a three month period.

  20. Patterns and Determinants of Treatment Seeking among Previously Untreated Psychotic Patients in Aceh Province, Indonesia: A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Marthoenis Marthoenis

    2016-01-01

    Full Text Available Immediate treatment of first-episode psychosis is essential in order to achieve a positive outcome. However, Indonesian psychiatric patients often delay accessing health services, the reason for which is not yet fully understood. The current study aimed to understand patterns of treatment seeking and to reveal determinants of the delay in accessing psychiatric care among first-time user psychotic patients. Qualitative interviews were conducted with sixteen family members who accompanied the patients to a psychiatric hospital. Many families expressed beliefs that mental illness appertains to village sickness and not hospital sickness; therefore, they usually take the patients to traditional or religious healers before taking them to a health professional. They also identified various factors that potentially delay accessing psychiatric treatment: low literacy and beliefs about the cause of the illness, stigmatisation, the role of extended family, financial problems, and long distance to the psychiatric hospital. On the other hand, the family mentioned various factors related to timely help seeking, including being a well-educated family, living closer to health facilities, previous experience of successful psychotic therapy, and having more positive symptoms of psychosis. The findings call for mental health awareness campaigns in the community.

  1. Cerebral blood flow and intracranial pulsatility studied with MRI: measurement, physiological and pathophysiological aspects

    Energy Technology Data Exchange (ETDEWEB)

    Waahlin, Anders

    2012-07-01

    During each cardiac cycle pulsatile arterial blood inflates the vascular bed of the brain, forcing cerebrospinal fluid (CSF) and venous blood out of the cranium. Excessive arterial pulsatility may be part of a harmful mechanism causing cognitive decline among elderly. Additionally, restricted venous flow from the brain is suggested as the cause of multiple sclerosis. Addressing hypotheses derived from these observations requires accurate and reliable investigational methods. This work focused on assessing the pulsatile waveform of cerebral arterial, venous and CSF flows. The overall aim of this dissertation was to explore cerebral blood flow and intracranial pulsatility using MRI, with respect to measurement, physiological and pathophysiological aspects.Two-dimensional phase contrast magnetic resonance imaging (2D PCMRI) was used to assess the pulsatile waveforms of cerebral arterial, venous and CSF flow. The repeatability was assessed in healthy young subjects. The 2D PCMRI measurements of cerebral arterial, venous and CSF pulsatility were generally repeatable but the pulsatility decreased systematically during the investigation. A method combining 2D PCMRI measurements with invasive CSF infusion tests to determine the magnitude and distribution of compliance within the craniospinal system was developed and applied in a group of healthy elderly. The intracranial space contained approximately two thirds of the total craniospinal compliance. The magnitude of craniospinal compliance was less than suggested in previous studies. The vascular hypothesis for multiple sclerosis was tested. Venous drainage in the internal jugular veins was compared between healthy controls and multiple sclerosis patients using 2D PCMRI. For both groups, a great variability in the internal jugular flow was observed but no pattern specific to multiple sclerosis could be found. Relationships between regional brain volumes and potential biomarkers of intracranial cardiac-related pulsatile

  2. Cerebral blood flow and intracranial pulsatility studied with MRI: measurement, physiological and pathophysiological aspects

    International Nuclear Information System (INIS)

    Waahlin, Anders

    2012-01-01

    During each cardiac cycle pulsatile arterial blood inflates the vascular bed of the brain, forcing cerebrospinal fluid (CSF) and venous blood out of the cranium. Excessive arterial pulsatility may be part of a harmful mechanism causing cognitive decline among elderly. Additionally, restricted venous flow from the brain is suggested as the cause of multiple sclerosis. Addressing hypotheses derived from these observations requires accurate and reliable investigational methods. This work focused on assessing the pulsatile waveform of cerebral arterial, venous and CSF flows. The overall aim of this dissertation was to explore cerebral blood flow and intracranial pulsatility using MRI, with respect to measurement, physiological and pathophysiological aspects.Two-dimensional phase contrast magnetic resonance imaging (2D PCMRI) was used to assess the pulsatile waveforms of cerebral arterial, venous and CSF flow. The repeatability was assessed in healthy young subjects. The 2D PCMRI measurements of cerebral arterial, venous and CSF pulsatility were generally repeatable but the pulsatility decreased systematically during the investigation. A method combining 2D PCMRI measurements with invasive CSF infusion tests to determine the magnitude and distribution of compliance within the craniospinal system was developed and applied in a group of healthy elderly. The intracranial space contained approximately two thirds of the total craniospinal compliance. The magnitude of craniospinal compliance was less than suggested in previous studies. The vascular hypothesis for multiple sclerosis was tested. Venous drainage in the internal jugular veins was compared between healthy controls and multiple sclerosis patients using 2D PCMRI. For both groups, a great variability in the internal jugular flow was observed but no pattern specific to multiple sclerosis could be found. Relationships between regional brain volumes and potential biomarkers of intracranial cardiac-related pulsatile

  3. Adaptive changes in early and late blind: a fMRI study of Braille reading.

    Science.gov (United States)

    Burton, H; Snyder, A Z; Conturo, T E; Akbudak, E; Ollinger, J M; Raichle, M E

    2002-01-01

    Braille reading depends on remarkable adaptations that connect the somatosensory system to language. We hypothesized that the pattern of cortical activations in blind individuals reading Braille would reflect these adaptations. Activations in visual (occipital-temporal), frontal-language, and somatosensory cortex in blind individuals reading Braille were examined for evidence of differences relative to previously reported studies of sighted subjects reading print or receiving tactile stimulation. Nine congenitally blind and seven late-onset blind subjects were studied with fMRI as they covertly performed verb generation in response to reading Braille embossed nouns. The control task was reading the nonlexical Braille string "######". This study emphasized image analysis in individual subjects rather than pooled data. Group differences were examined by comparing magnitudes and spatial extent of activated regions first determined to be significant using the general linear model. The major adaptive change was robust activation of visual cortex despite the complete absence of vision in all subjects. This included foci in peri-calcarine, lingual, cuneus and fusiform cortex, and in the lateral and superior occipital gyri encompassing primary (V1), secondary (V2), and higher tier (VP, V4v, LO and possibly V3A) visual areas previously identified in sighted subjects. Subjects who never had vision differed from late blind subjects in showing even greater activity in occipital-temporal cortex, provisionally corresponding to V5/MT and V8. In addition, the early blind had stronger activation of occipital cortex located contralateral to the hand used for reading Braille. Responses in frontal and parietal cortex were nearly identical in both subject groups. There was no evidence of modifications in frontal cortex language areas (inferior frontal gyrus and dorsolateral prefrontal cortex). Surprisingly, there was also no evidence of an adaptive expansion of the somatosensory or

  4. Monitoring the early signs of cognitive decline in elderly by computer games: an MRI study.

    Directory of Open Access Journals (Sweden)

    Enikő Sirály

    Full Text Available It is anticipated that current and future preventive therapies will likely be more effective in the early stages of dementia, when everyday functioning is not affected. Accordingly the early identification of people at risk is particularly important. In most cases, when subjects visit an expert and are examined using neuropsychological tests, the disease has already been developed. Contrary to this cognitive games are played by healthy, well functioning elderly people, subjects who should be monitored for early signs. Further advantages of cognitive games are their accessibility and their cost-effectiveness.The aim of the investigation was to show that computer games can help to identify those who are at risk. In order to validate games analysis was completed which measured the correlations between results of the 'Find the Pairs' memory game and the volumes of the temporal brain regions previously found to be good predictors of later cognitive decline.34 healthy elderly subjects were enrolled in the study. The volume of the cerebral structures was measured by MRI. Cortical reconstruction and volumetric segmentation were performed by Freesurfer.There was a correlation between the number of attempts and the time required to complete the memory game and the volume of the entorhinal cortex, the temporal pole, and the hippocampus. There was also a correlation between the results of the Paired Associates Learning (PAL test and the memory game.The results gathered support the initial hypothesis that healthy elderly subjects achieving lower scores in the memory game have increased level of atrophy in the temporal brain structures and showed a decreased performance in the PAL test. Based on these results it can be concluded that memory games may be useful in early screening for cognitive decline.

  5. High prevalence of brain pathology in violent prisoners: a qualitative CT and MRI scan study.

    Science.gov (United States)

    Schiltz, Kolja; Witzel, Joachim G; Bausch-Hölterhoff, Josef; Bogerts, Bernhard

    2013-10-01

    The aim of this study was to determine the frequency and extent of brain anomalies in a large sample of incarcerated violent offenders not previously considered neuropsychiatrically ill, in comparison with non-violent offenders and non-offending controls. MRI and CT brain scans from 287 male prison inmates (162 violent and 125 non-violent) not diagnosed as mentally ill before that were obtained due to headache, vertigo or psychological complaints during imprisonment were assessed and compared to 52 non-criminal controls. Brain scans were rated qualitatively with respect to evidence of structural brain damage. Each case received a semiquantitative rating of "normal" (=0), "questionably abnormal" (=1) or "definitely abnormal" (=2) for the lateral ventricles, frontal/parietal cortex and medial temporal structures bilaterally as well as third ventricle. Overall, offenders displayed a significantly higher rate of morphological abnormality, with the violent offenders scoring significantly higher than non-violent offenders and controls. This difference was statistically detectable for frontal/parietal cortex, medial temporal structures, third ventricle and the left but not the right lateral ventricle. The remarkable prevalence of brain pathology in convicted violent prisoners detectable by neuroradiological routine assessment not only highlights the importance of frontal and temporal structures in the control of social, and specifically of violent behaviour, but also raises questions on the legal culpability of violent offenders with brain abnormalities. The high proportion of undetected presence of structural brain damage emphasizes the need that in violent criminals, the comprehensive routine neuropsychiatric assessment usually performed in routine forensic psychiatric expertises should be complemented with brain imaging.

  6. Monitoring the early signs of cognitive decline in elderly by computer games: an MRI study.

    Science.gov (United States)

    Sirály, Enikő; Szabó, Ádám; Szita, Bernadett; Kovács, Vivienne; Fodor, Zsuzsanna; Marosi, Csilla; Salacz, Pál; Hidasi, Zoltán; Maros, Viktor; Hanák, Péter; Csibri, Éva; Csukly, Gábor

    2015-01-01

    It is anticipated that current and future preventive therapies will likely be more effective in the early stages of dementia, when everyday functioning is not affected. Accordingly the early identification of people at risk is particularly important. In most cases, when subjects visit an expert and are examined using neuropsychological tests, the disease has already been developed. Contrary to this cognitive games are played by healthy, well functioning elderly people, subjects who should be monitored for early signs. Further advantages of cognitive games are their accessibility and their cost-effectiveness. The aim of the investigation was to show that computer games can help to identify those who are at risk. In order to validate games analysis was completed which measured the correlations between results of the 'Find the Pairs' memory game and the volumes of the temporal brain regions previously found to be good predictors of later cognitive decline. 34 healthy elderly subjects were enrolled in the study. The volume of the cerebral structures was measured by MRI. Cortical reconstruction and volumetric segmentation were performed by Freesurfer. There was a correlation between the number of attempts and the time required to complete the memory game and the volume of the entorhinal cortex, the temporal pole, and the hippocampus. There was also a correlation between the results of the Paired Associates Learning (PAL) test and the memory game. The results gathered support the initial hypothesis that healthy elderly subjects achieving lower scores in the memory game have increased level of atrophy in the temporal brain structures and showed a decreased performance in the PAL test. Based on these results it can be concluded that memory games may be useful in early screening for cognitive decline.

  7. A functional MRI study of happy and sad emotions in music with and without lyrics

    Directory of Open Access Journals (Sweden)

    Elvira eBrattico

    2011-12-01

    Full Text Available Musical emotions, such as happiness and sadness, have been investigated using instrumental music devoid of linguistic content. However, pop and rock, the most common musical genres, utilize lyrics for conveying emotions. Using participants’ self-selected musical excerpts, we studied their behavior and brain responses to elucidate how lyrics interact with musical emotion processing, as reflected by emotion recognition and activation of limbic areas involved in affective experience. We extracted samples from subjects’ selections of sad and happy pieces and sorted them according to the presence of lyrics. Acoustic feature analysis showed that music with lyrics differed from music without lyrics in spectral centroid, a feature related to perceptual brightness, whereas sad music with lyrics did not diverge from happy music without lyrics, indicating the role of other factors in emotion classification. Behavioral ratings revealed that happy music without lyrics induced stronger positive emotions than happy music with lyrics. We also acquired functional magnetic resonance imaging (fMRI data while subjects performed affective tasks regarding the music. First, using ecological and acoustically variable stimuli, we broadened previous findings about the brain processing of musical emotions and of songs versus instrumental music. Additionally, contrasts between sad music with versus without lyrics recruited the parahippocampal gyrus, the amygdala, the claustrum, the putamen, the precentral gyrus, the medial and inferior frontal gyri (including Broca’s area, and the auditory cortex, while the reverse contrast produced no activations. Happy music without lyrics activated structures of the limbic system and the right pars opercularis of the inferior frontal gyrus, whereas auditory regions alone responded to happy music with lyrics. These findings point to the role of acoustic cues for the experience of happiness in music and to the importance of lyrics

  8. A Questionnaire Study on the Attitudes and Previous Experience of Croatian Family Physicians toward their Preparedness for Disaster Management.

    Science.gov (United States)

    Pekez-Pavliško, Tanja; Račić, Maja; Jurišić, Dinka

    2018-04-01

    To explore family physicians' attitudes, previous experience and self-assessed preparedness to respond or to assist in mass casualty incidents in Croatia. The cross-sectional survey was carried out during January 2017. Study participants were recruited through a Facebook group that brings together family physicians from Croatia. They were asked to complete the questionnaire, which was distributed via google.docs. Knowledge and attitudes toward disaster preparedness were evaluated by 18 questions. Analysis of variance, Student t test and Kruskal-Wallis test t were used for statistical analysis. Risk awareness of disasters was high among respondents (M = 4.89, SD=0.450). Only 16.4 of respondents have participated in the management of disaster at the scene. The majority (73.8%) of physicians have not been participating in any educational activity dealing with disaster over the past two years. Family physicians believed they are not well prepared to participate in national (M = 3.02, SD=0.856) and local community emergency response system for disaster (M = 3.16, SD=1.119). Male physicians scored higher preparedness to participate in national emergency response system for disaster ( p =0.012), to carry out accepted triage principles used in the disaster situation ( p =0.003) and recognize differences in health assessments indicating potential exposure to specific agents ( p =0,001) compared to their female colleagues. Croatian primary healthcare system attracts many young physicians, who can be an important part of disaster and emergency management. However, the lack of experience despite a high motivation indicates a need for inclusion of disaster medicine training during undergraduate studies and annual educational activities.

  9. Previous injuries and some training characteristics predict running-related injuries in recreational runners: a prospective cohort study.

    Science.gov (United States)

    Hespanhol Junior, Luiz Carlos; Pena Costa, Leonardo Oliveira; Lopes, Alexandre Dias

    2013-12-01

    What is the incidence of running-related injuries (RRIs) in recreational runners? Which personal and training characteristics predict RRIs in recreational runners? Prospective cohort study. A total of 200 recreational runners answered a fortnightly online survey containing questions about their running routine, races, and presence of RRI. These runners were followed-up for a period of 12 weeks. The primary outcome of this study was running-related injury. The incidence of injuries was calculated taking into account the exposure to running and was expressed by RRI/1000 hours. The association between potential predictive factors and RRIs was estimated using generalised estimating equation models. A total of 84 RRIs were registered in 60 (31%) of the 191 recreational runners who completed all follow-up surveys. Of the injured runners 30% (n=18/60) developed two or more RRIs, with 5/18 (28%) being recurrences. The incidence of RRI was 10 RRI/1000 hours of running exposure. The main type of RRI observed was muscle injuries (30%, n=25/84). The knee was the most commonly affected anatomical region (19%, n=16/84). The variables associated with RRI were: previous RRI (OR 1.88, 95% CI 1.01 to 3.51), duration of training although the effect was very small (OR 1.01, 95% CI 1.00 to 1.02), speed training (OR 1.46, 95% CI 1.02 to 2.10), and interval training (OR 0.61, 95% CI 0.43 to 0.88). Physiotherapists should be aware and advise runners that past RRI and speed training are associated with increased risk of further RRI, while interval training is associated with lower risk, although these associations may not be causative. Copyright © 2013 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.

  10. A study on utility of magnetic resonance imaging for female pelvic cavity using enteral MRI contrast media

    International Nuclear Information System (INIS)

    Kim, Ham Gyum

    1997-01-01

    For radiological test in soft tissue or neighboring part with same signal intensity, proper test method and equipment shall be selected as needed. In case of female pelvic cavity, ultrasonography or computed tomography alternatively used, but MRI can be more usefully applied to design treatment method or operation plan by improving the diagnostic accuracy and careful observation of lesion characteristics. Magnetic Resonance Imaging using recently developed Enteral MRI contrast media can acquire more diagnostic information than using only intravenous contrast media. Thus this study attempted to examine the utility of anatomic structure and diagnostic acquisition by imaging the female pelvic cavity using Enteral MRI contrast media. As a result of analyzing magnetic resonance imaging after administering Enteral MRI contrast media to pelvic cavity suspect patients, more diagnostic information media could be acquired than only using intravenous contrast. Especially, in the diagnosis of lesion position, shape, distinction from neighboring tissues it is thought that external Enteral MRI contrast media should be used

  11. Interventional MRI

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Junta; Dohi, Michiko; Yoshihiro, Akiko; Mogami, Takuji; Kuwada, Tomoko; Nakata, Norio [Jikei Univ., Chiba (Japan). Kashiwa Hospital

    2000-06-01

    Open type MR system and fast sequence is now available and MRI becomes a new modality for interventional Radiology, including biopsy, drainage operation, and monitoring for minimally invasive therapy. Experimental studies of temperature monitoring were performed under hot and cold status. Signal changes of porcine disc and meat under microwave and laser ablation were observed as low signal area by signal intensity method. Using proton chemical shift method, signal change by laser ablation was displaced color imaging and correlated with thermometric temperature measurement. The very T2 relaxation time of ice affords excellent contrast between ice and surrounding gelatin tissue allowing acute depiction of the extent of the iceball under MRI. (author)

  12. Pain empathy in schizophrenia: an fMRI study

    OpenAIRE

    Horan, William P.; Jimenez, Amy M.; Lee, Junghee; Wynn, Jonathan K.; Eisenberger, Naomi I.; Green, Michael F.

    2016-01-01

    Although it has been proposed that schizophrenia is characterized by impaired empathy, several recent studies found intact neural responses on tasks measuring the affective subdomain of empathy. This study further examined affective empathy in 21 schizophrenia outpatients and 21 healthy controls using a validated pain empathy paradigm with two components: (i) observing videos of people described as medical patients who were receiving a painful sound stimulation treatment; (ii) listening to th...

  13. Modafinil alters intrinsic functional connectivity of the right posterior insula: a pharmacological resting state fMRI study.

    Directory of Open Access Journals (Sweden)

    Nicoletta Cera

    Full Text Available Modafinil is employed for the treatment of narcolepsy and has also been, off-label, used to treat cognitive dysfunction in neuropsychiatric disorders. In a previous study, we have reported that single dose administration of modafinil in healthy young subjects enhances fluid reasoning and affects resting state activity in the Fronto Parietal Control (FPC and Dorsal Attention (DAN networks. No changes were found in the Salience Network (SN, a surprising result as the network is involved in the modulation of emotional and fluid reasoning. The insula is crucial hub of the SN and functionally divided in anterior and posterior subregions.Using a seed-based approach, we have now analyzed effects of modafinil on the functional connectivity (FC of insular subregions.Analysis of FC with resting state fMRI (rs-FMRI revealed increased FC between the right posterior insula and the putamen, the superior frontal gyrus and the anterior cingulate cortex in the modafinil-treated group.Modafinil is considered a putative cognitive enhancer. The rs-fMRI modifications that we have found are consistent with the drug cognitive enhancing properties and indicate subregional targets of action.ClinicalTrials.gov NCT01684306.

  14. Functional connectivity associated with social networks in older adults: A resting-state fMRI study.

    Science.gov (United States)

    Pillemer, Sarah; Holtzer, Roee; Blumen, Helena M

    2017-06-01

    Poor social networks and decreased levels of social support are associated with worse mood, health, and cognition in younger and older adults. Yet, we know very little about the brain substrates associated with social networks and social support, particularly in older adults. This study examined functional brain substrates associated with social networks using the Social Network Index (SNI) and resting-state functional magnetic resonance imaging (fMRI). Resting-state fMRI data from 28 non-demented older adults were analyzed with independent components analyses. As expected, four established resting-state networks-previously linked to motor, vision, speech, and other language functions-correlated with the quality (SNI-1: total number of high-contact roles of a respondent) and quantity (SNI-2: total number of individuals in a respondent's social network) of social networks: a sensorimotor, a visual, a vestibular/insular, and a left frontoparietal network. Moreover, SNI-1 was associated with greater functional connectivity in the lateral prefrontal regions of the left frontoparietal network, while SNI-2 was associated with greater functional connectivity in the medial prefrontal regions of this network. Thus, lateral prefrontal regions may be particularly linked to the quality of social networks while medial prefrontal regions may be particularly linked to the quantity of social networks.

  15. Role of MRI in differentiating benign from malignant breast lesions ...

    African Journals Online (AJOL)

    Mohamed Ahmed Youssef

    2017-02-15

    Feb 15, 2017 ... renal dysfunction or previous reactions to contrast agents and will relieve the cost of examination.4,5. The aim of the study was to evaluate the role of the magnetic resonance imaging in differentiation of benign from malignant breast lesions using dynamic contrast enhanced MRI (DCE-MRI) and diffusion ...

  16. MRI EVALUATION OF PAINFUL KNEE: A STUDY AT KATURI TERTIARY REFERRAL CENTER

    Directory of Open Access Journals (Sweden)

    Bhimeswarao Pasupuleti

    2015-02-01

    Full Text Available INTRODUCTION: Normal knee joint functional activity is essential for day to day life . The number of patients with complaints of painful knee joint is quite significant and therefore magnetic resonance imaging (MRI of the knee is of great value in understanding and to diagnose the varied pathologies causing painful knee joint. The information obtained from conventional radiographs of the knee is limited, and by CT scans is limited to bone pathog l y with limited information about ligaments and synovium. AIMS AND OBJECTIVES : a To describe the MRI features in various types of traumatic and non - traumatic knee pain . b To identify the common lesions seen in the knee joint . METHODOLOGY : The study population included 100 patients who underwent MR imaging of the knee who presented with knee pain to the DEPARTMENT OF RADIOLOGY, KATURI MEDICALCOLLEGE referred by the clinician. STUDY PERIOD: Nov 2010 to Oct 2012 . STUDY DESIGN : Descriptive study . All the MRI scans of the knee in this study were performed using GE Signa Profile EXCITE MR machine with a 0.2 tesla field strength magnet in a closely coupled extremity coil. RESULTS AND DISCUSSION : The pathology of knee joint is broadly classified as traumatic and non - traumatic. Traumatic pathol o gy mainly included the ligament injuries and non - traumatic included arthritis, cysts and neoplastic lesions

  17. SU-E-J-257: Image Artifacts Caused by Implanted Calypso Beacons in MRI Studies

    International Nuclear Information System (INIS)

    Amro, H; Chetty, I; Gordon, J; Wen, N

    2014-01-01

    Purpose: The presence of Calypso Beacon-transponders in patients can cause artifacts during MRI imaging studies. This could be a problem for post-treatment follow up of cancer patients using MRI studies to evaluate metastasis and for functional imaging studies.This work assesses (1) the volume immediately surrounding the transponders that will not be visualized by the MRI due to the beacons, and (2) the dependence of the non-visualized volume on beacon orientation, and scanning techniques. Methods: Two phantoms were used in this study (1) water filled box, (2) and a 2300 cc block of pork meat. Calypso beacons were implanted in the phantoms both in parallel and perpendicular orientations with respect to the MR scanner magnetic field. MR image series of the phantom were obtained with on a 1.0T high field open MR-SIM with multiple pulse sequences, for example, T1-weighted fast field echo and T2-weighted turbo spin echo. Results: On average, a no-signal region with 2 cm radius and 3 cm length was measured. Image artifacts are more significant when beacons are placed parallel to scanner magnetic field; the no-signal area around the beacon was about 0.5 cm larger in orthogonal orientation. The no-signal region surrounding the beacons slightly varies in dimension for the different pulse sequences. Conclusion: The use of Calypso beacons can prohibit the use of MRI studies in post-treatment assessments, especially in the immediate region surrounding the implanted beacon. A characterization of the MR scanner by identifying the no-signal regions due to implanted beacons is essential. This may render the use of Calypso beacons useful for some cases and give the treating physician a chance to identify those patients prior to beacon implantation

  18. Neural plasticity in functional and anatomical MRI studies of children with Tourette syndrome.

    Science.gov (United States)

    Eichele, Heike; Plessen, Kerstin J

    2013-01-01

    Tourette syndrome (TS) is a neuropsychiatric disorder with childhood onset characterized by chronic motor and vocal tics. The typical clinical course of an attenuation of symptoms during adolescence in parallel with the emerging self-regulatory control during development suggests that plastic processes may play an important role in the development of tic symptoms. We conducted a systematic search to identify existing imaging studies (both anatomical and functional magnetic resonance imaging [fMRI]) in young persons under the age of 19 years with TS. The final search resulted in 13 original studies, which were reviewed with a focus on findings suggesting adaptive processes (using fMRI) and plasticity (using anatomical MRI). Differences in brain activation compared to healthy controls during tasks that require overriding of prepotent responses help to understand compensatory pathways in children with TS. Along with alterations in regions putatively representing the origin of tics, deviations in several other regions most likely represent an activity-dependent neural plasticity that help to modulate tic severity, such as the prefrontal cortex, but also in the corpus callosum and the limbic system. Factors that potentially influence the development of adaptive changes in the brain of children with TS are age, comorbidity with other developmental disorders, medication use, IQ along with study-design or MRI techniques for acquisition, and analysis of data. The most prominent limitation of all studies is their cross-sectional design. Longitudinal studies extending to younger age groups and to children at risk for developing TS hopefully will confirm findings of neural plasticity in future investigations.

  19. SU-E-J-257: Image Artifacts Caused by Implanted Calypso Beacons in MRI Studies

    Energy Technology Data Exchange (ETDEWEB)

    Amro, H; Chetty, I; Gordon, J; Wen, N [Henry Ford Health System, Detroit, MI (United States)

    2014-06-01

    Purpose: The presence of Calypso Beacon-transponders in patients can cause artifacts during MRI imaging studies. This could be a problem for post-treatment follow up of cancer patients using MRI studies to evaluate metastasis and for functional imaging studies.This work assesses (1) the volume immediately surrounding the transponders that will not be visualized by the MRI due to the beacons, and (2) the dependence of the non-visualized volume on beacon orientation, and scanning techniques. Methods: Two phantoms were used in this study (1) water filled box, (2) and a 2300 cc block of pork meat. Calypso beacons were implanted in the phantoms both in parallel and perpendicular orientations with respect to the MR scanner magnetic field. MR image series of the phantom were obtained with on a 1.0T high field open MR-SIM with multiple pulse sequences, for example, T1-weighted fast field echo and T2-weighted turbo spin echo. Results: On average, a no-signal region with 2 cm radius and 3 cm length was measured. Image artifacts are more significant when beacons are placed parallel to scanner magnetic field; the no-signal area around the beacon was about 0.5 cm larger in orthogonal orientation. The no-signal region surrounding the beacons slightly varies in dimension for the different pulse sequences. Conclusion: The use of Calypso beacons can prohibit the use of MRI studies in post-treatment assessments, especially in the immediate region surrounding the implanted beacon. A characterization of the MR scanner by identifying the no-signal regions due to implanted beacons is essential. This may render the use of Calypso beacons useful for some cases and give the treating physician a chance to identify those patients prior to beacon implantation.

  20. Five cases of a Joseph disease family with non-REM sleep apnea and MRI study

    International Nuclear Information System (INIS)

    Kitamura, Junichi; Tsuruta, Kazuhito; Yamamura, Yoshinori; Kurihara, Teruyuki; Matsukura, Shigeru

    1987-01-01

    Four male and one female patients of a new Joseph disease family in southern Kyushu are presented. This disorder is inherited by autosomal dominant trait. The clinical symptoms are characterized by bulging eyes, ophthalmoplegia, dysarthria, rigospasticity of the lower limbs, marked dystonia and bradykinesia. In our cases, extrapyramidal symptoms were improved by amantadine and L-Dopa therapy. CSF homovanilic acid (HVA) was markedly reduced. Muscle biopsy and electromyographic studies revealed neurogenic changes. MRI revealed mild atrophy of frontal lobe and cerebellum, and marked atrophy of brain stem. These findings were consistent with the clinical manifestations. Our case had central type sleep apnea by sleep EEG and polygraphic studies. This is the first report about sleep apnea and MRI of Joseph disease. (author)

  1. Five cases of a Joseph disease family with non-REM sleep apnea and MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Kitamura, Junichi; Tsuruta, Kazuhito; Yamamura, Yoshinori; Kurihara, Teruyuki; Matsukura, Shigeru

    1987-09-01

    Four male and one female patients of a new Joseph disease family in southern Kyushu are presented. This disorder is inherited by autosomal dominant trait. The clinical symptoms are characterized by bulging eyes, ophthalmoplegia, dysarthria, rigospasticity of the lower limbs, marked dystonia and bradykinesia. In our cases, extrapyramidal symptoms were improved by amantadine and L-dopa therapy. CSF homovanilic acid (HVA) was markedly reduced. Muscle biopsy and electromyographic studies revealed neurogenic changes. MRI revealed mild atrophy of frontal lobe and cerebellum, and marked atrophy of brain stem. These findings were consistent with the clinical manifestations. Our case had central type sleep apnea by sleep EEG and polygraphic studies. This is the first report about sleep apnea and MRI of Joseph disease.

  2. The insula is not specifically involved in disgust processing: an fMRI study.

    Science.gov (United States)

    Schienle, A; Stark, R; Walter, B; Blecker, C; Ott, U; Kirsch, P; Sammer, G; Vaitl, D

    2002-11-15

    fMRI studies have shown that the perception of facial disgust expressions specifically activates the insula. The present fMRI study investigated whether this structure is also involved in the processing of visual stimuli depicting non-mimic disgust elicitors compared to fear-inducing and neutral scenes. Twelve female subjects were scanned while viewing alternating blocks of 40 disgust-inducing, 40 fear-inducing and 40 affectively neutral pictures, shown for 1.5 s each. Afterwards, affective ratings were assessed. The disgust pictures, rated as highly repulsive, induced activation in the insula, the amygdala, the orbitofrontal and occipito-temporal cortex. Since during the fear condition the insula was also involved, our findings do not fit the idea of the insula as a specific disgust processor.

  3. Comparison of Ct and MRI in the study of the pituitary gland

    International Nuclear Information System (INIS)

    Juliani, G.; Avataneo, T.; Potenzoni, F.; Sorrentino, T

    1989-01-01

    Normal CT and MR anatomy was studied in two series (53 and 25 cases respectively) of young volunteers of both sexes, asymptomatic and certainly without lesions of the pituitary gland. 115 other pathological cases (73 hyperprolactinemias, 8 acromegalies, 15 Cushing syndromes, 2 hyperthyroidisms, 17 non-secreting adenomas) were examined using both CT and MRI. Both an accurate review of the relative literature and the results of our own series prove that MR is superior to CT in diagnosing pituitary microadenomas (3.2% not diagnosed with MRI and 25.8% not diagnosed with CT), in the follow-up of prolactinomas subjected to medical therapy and in the study of extrasellar involvement of pituitery adenomas, particularly with regard to the demonstration of compression of the optic chiasma

  4. Blood donations from previously transfused or pregnant donors: a multicenter study to determine the frequency of alloexposure.

    Science.gov (United States)

    Rios, Jorge A; Schlumpf, Karen S; Kakaiya, Ram M; Triulzi, Darrell J; Roback, John D; Kleinman, Steve H; Murphy, Edward L; Gottschall, Jerome L; Carey, Patricia M

    2011-06-01

    Transfusion-related acute lung injury (TRALI) mitigation strategies include the deferral of female donors from apheresis platelet (PLT) donations and the distribution of plasma for transfusion from male donors only. We studied the implications of these policies in terms of component loss at six blood centers in the United States. We collected data from allogeneic blood donors making whole blood and blood component donations during calendar years 2006 through 2008. We analyzed the distribution of donations in terms of the sex, transfusion and pregnancy histories, and blood type. A TRALI mitigation policy that would not allow plasma from female whole blood donors to be prepared into transfusable plasma components would result in nearly a 50% reduction in the units of whole blood available for plasma manufacturing and would decrease the number of type AB plasma units that could be made from whole blood donations by the same amount. Deferral of all female apheresis PLT donors, all female apheresis PLT donors with histories of prior pregnancies, or all female apheresis PLT donors with histories of prior pregnancies and positive screening test results for antibodies to human leukocyte antigens (HLAs) will result in a loss of 37.1, 22.5, and 5.4% of all apheresis PLT donations, respectively. A TRALI mitigation policy that only defers female apheresis PLT donors with previous pregnancies and HLAs would result in an approximately 5% decrease in the inventory of apheresis PLTs, but would eliminate a large proportion of components that are associated with TRALI. © 2010 American Association of Blood Banks.

  5. PCNL - a comparative study in nonoperated and in previously operated (open nephrolithotomy/pyelolithotomy patients - a single-surgeon experience

    Directory of Open Access Journals (Sweden)

    Rahul Gupta

    2011-12-01

    Full Text Available PURPOSE: Re-procedure in patients with history of open stone surgery is usually challenging due to the alteration in the retroperitoneal anatomy. The aim of this study was to determine the possible impact of open renal surgery on the efficacy and morbidity of subsequent percutaneous nephrolithotomy (PCNL. MATERIALS AND METHODS: From March 2009 until September 2010, 120 patients underwent PCNL. Of these, 20 patients were excluded (tubeless or bilateral simultaneous PCNL. Of the remaining 100, 55 primary patients were categorized as Group 1 and the remaining (previous open nephrolithotomy as Group 2. Standard preoperative evaluation was carried out prior to intervention, Statistical analysis was performed using SPSS v. 11 with the chi-square test, independent samples t-test, and Mann-Whitney U test. A p-value < 0.05 was taken as statistically significant. RESULTS: Both groups were similar in demographic profile and stone burden. Attempts to access the PCS was less in Group 1 compared to Group 2 (1.2 + 1 2 vs 3 + 1.3 respectively and this was statistically significant (p < 0.04. However, the mean operative time between the two groups was not statistically significant (p = 0.44. Blood transfusion rate was comparable in the two groups (p = 0.24. One patient in Group 2 developed hemothorax following a supra-11th puncture. Remaining complications were comparable in both groups. CONCLUSION: Patients with past history of renal stone surgery may need more attempts to access the pelvicaliceal system and have difficulty in tract dilation secondary to retroperitoneal scarring. But overall morbidity and efficacy is same in both groups.

  6. MRI study of hydrophilic xanthan tablets with incorporated model drug

    OpenAIRE

    Mikac, Urša; Baumgartner, Saša; Sepe, Ana; Kristl, Julijana

    2015-01-01

    Magnetic resonance imaging was used to study swelling dynamics and hydrogel formation of xanthan tablets with or without Pentoxifylline drug in water and HCl pH 1.2 media at two different ionic strengths. Significant changes were observed only in the erosion front positions leading to different hydrogel thicknesses. The impact of the drug on the hydrogel thickness was found to be dependent on the medium conditions at high enough drug amount. The drug does not change the hydrogel thickness ...

  7. Mystery of alar ligament rupture: Value of MRI in whiplash injuries - biomechanical, anatomical and clinical studies

    International Nuclear Information System (INIS)

    Bitterling, H.; Brueckmann, H.; Staebler, A.

    2007-01-01

    Purpose: Whiplash injury of the cervical spine is a frequent issue in medical expertise and causes enormous consequential costs for motor insurance companies. Some authors accuse posttraumatic changes of alar ligaments to be causative for consequential disturbances. Materials and methods: Review of recent studies on biomechanics, anatomical and clinical MR imaging. Results: Biomechanical experiments can not induce according injuries of alar ligaments. Although MRI provides excellent visualization of alar ligaments, the range of normal variants is high. (orig.)

  8. Altered resting-state functional connectivity in post-traumatic stress disorder: a perfusion MRI study

    Science.gov (United States)

    Li, Baojuan; Liu, Jian; Liu, Yang; Lu, Hong-Bing; Yin, Hong

    2013-03-01

    The majority of studies on posttraumatic stress disorder (PTSD) so far have focused on delineating patterns of activations during cognitive processes. Recently, more and more researches have started to investigate functional connectivity in PTSD subjects using BOLD-fMRI. Functional connectivity analysis has been demonstrated as a powerful approach to identify biomarkers of different brain diseases. This study aimed to detect resting-state functional connectivity abnormities in patients with PTSD using arterial spin labeling (ASL) fMRI. As a completely non-invasive technique, ASL allows quantitative estimates of cerebral blood flow (CBF). Compared with BOLD-fMRI, ASL fMRI has many advantages, including less low-frequency signal drifts, superior functional localization, etc. In the current study, ASL images were collected from 10 survivors in mining disaster with recent onset PTSD and 10 survivors without PTSD. Decreased regional CBF in the right middle temporal gyrus, lingual gyrus, and postcentral gyrus was detected in the PTSD patients. Seed-based resting-state functional connectivity analysis was performed using an area in the right middle temporal gyrus as region of interest. Compared with the non-PTSD group, the PTSD subjects demonstrated increased functional connectivity between the right middle temporal gyrus and the right superior temporal gyrus, the left middle temporal gyrus. Meanwhile, decreased functional connectivity between the right middle temporal gyrus and the right postcentral gyrus, the right superior parietal lobule was also found in the PTSD patients. This is the first study which investigated resting-state functional connectivity in PTSD using ASL images. The results may provide new insight into the neural substrates of PTSD.

  9. Middle and Inferior Temporal Gyrus Gray Matter Volume Abnormalities in Chronic Schizophrenia: An MRI Study

    OpenAIRE

    Onitsuka, Toshiaki; Shenton, Martha E.; Salisbury, Dean F.; Dickey, Chandlee C.; Kasai, Kiyoto; Toner, Sarah K.; Frumin, Melissa; Kikinis, Ron; Jolesz, Ferenc A.; McCarley, Robert W.

    2004-01-01

    Objective: The middle temporal gyrus and inferior temporal gyrus subserve language and semantic memory processing, visual perception, and multimodal sensory integration. Functional deficits in these cognitive processes have been well documented in patients with schizophrenia. However, there have been few in vivo structural magnetic resonance imaging (MRI) studies of the middle temporal gyrus and inferior temporal gyrus in schizophrenia. Method: Middle temporal gyrus and inferior temporal gyru...

  10. Differentiating between bipolar and unipolar depression in functional and structural MRI studies.

    Science.gov (United States)

    Han, Kyu-Man; De Berardis, Domenico; Fornaro, Michele; Kim, Yong-Ku

    2018-03-28

    Distinguishing depression in bipolar disorder (BD) from unipolar depression (UD) solely based on clinical clues is difficult, which has led to the exploration of promising neural markers in neuroimaging measures for discriminating between BD depression and UD. In this article, we review structural and functional magnetic resonance imaging (MRI) studies that directly compare UD and BD depression based on neuroimaging modalities including functional MRI studies on regional brain activation or functional connectivity, structural MRI on gray or white matter morphology, and pattern classification analyses using a machine learning approach. Numerous studies have reported distinct functional and structural alterations in emotion- or reward-processing neural circuits between BD depression and UD. Different activation patterns in neural networks including the amygdala, anterior cingulate cortex (ACC), prefrontal cortex (PFC), and striatum during emotion-, reward-, or cognition-related tasks have been reported between BD and UD. A stronger functional connectivity pattern in BD was pronounced in default mode and in frontoparietal networks and brain regions including the PFC, ACC, parietal and temporal regions, and thalamus compared to UD. Gray matter volume differences in the ACC, hippocampus, amygdala, and dorsolateral prefrontal cortex (DLPFC) have been reported between BD and UD, along with a thinner DLPFC in BD compared to UD. BD showed reduced integrity in the anterior part of the corpus callosum and posterior cingulum compared to UD. Several studies performed pattern classification analysis using structural and functional MRI data to distinguish between UD and BD depression using a supervised machine learning approach, which yielded a moderate level of accuracy in classification. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Sunburn and sun-protective behaviors among adults with and without previous nonmelanoma skin cancer: a population-based study

    Science.gov (United States)

    Fischer, Alexander H.; Wang, Timothy S.; Yenokyan, Gayane; Kang, Sewon; Chien, Anna L.

    2016-01-01

    Background Individuals with previous nonmelanoma skin cancer (NMSC) are at increased risk for subsequent skin cancer, and should therefore limit UV exposure. Objective To determine whether individuals with previous NMSC engage in better sun protection than those with no skin cancer history. Methods We pooled self-reported data (2005 and 2010 National Health Interview Surveys) from US non-Hispanic white adults (758 with and 34,161 without previous NMSC). We calculated adjusted prevalence odds ratios (aPOR) and 95% confidence intervals (95% CI), taking into account the complex survey design. Results Individuals with previous NMSC versus no history of NMSC had higher rates of frequent use of shade (44.3% versus 27.0%; aPOR=1.41; 1.16–1.71), long sleeves (20.5% versus 7.7%; aPOR=1.55; 1.21–1.98), a wide-brimmed hat (26.1% versus 10.5%; aPOR=1.52; 1.24–1.87), and sunscreen (53.7% versus 33.1%; aPOR=2.11; 95% CI=1.73–2.59), but did not have significantly lower odds of recent sunburn (29.7% versus 40.7%; aPOR=0.95; 0.77–1.17). Among subjects with previous NMSC, recent sunburn was inversely associated with age, sun avoidance, and shade but not sunscreen. Limitations Self-reported cross-sectional data and unavailable information quantifying regular sun exposure. Conclusion Physicians should emphasize sunburn prevention when counseling patients with previous NMSC, especially younger adults, focusing on shade and sun avoidance over sunscreen. PMID:27198078

  12. Association between trochlear morphology and chondromalacia patella: an MRI study.

    Science.gov (United States)

    Duran, Semra; Cavusoglu, Mehtap; Kocadal, Onur; Sakman, Bulent

    This study aimed to compare trochlear morphology seen in magnetic resonance imaging between patients with chondromalacia patella and age-matched control patients without cartilage lesion. Trochlear morphology was evaluated using the lateral trochlear inclination, medial trochlear inclination, sulcus angle and trochlear angle on the axial magnetic resonance images. Consequently, an association between abnormal trochlear morphology and chondromalacia patella was identified in women. In particular, women with flattened lateral trochlea are at an increased risk of patellar cartilage structural damage. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Preclinical study of diagnostic performances of contrast-enhanced spectral mammography versus MRI for breast diseases in China.

    Science.gov (United States)

    Wang, Qingguo; Li, Kangan; Wang, Lihui; Zhang, Jianbing; Zhou, Zhiguo; Feng, Yan

    2016-01-01

    To evaluate diagnostic performances of CESM for breast diseases with comparison to breast MRI in China. Sixty-eight patients with 77 breast lesions underwent MR and CESM. Two radiologists interpreted either MRI or CESM images, separately and independently. BI-RADS 1-3 and BI-RADS 4-5 were classified into the suspicious benign and suspicious malignant groups. Diagnostic accuracy parameters were calculated. Receiver operating characteristic (ROC) curves were constructed for the two modalities. The agreement and correlation between maximum lesion diameter based on CESM and MRI, or CESM and pathology were analyzed. Diagnostic accuracy parameters for CESM were sensitivity 95.8 %, specificity 65.5 %, PPV 82.1 %, NPV 90.5 % and accuracy 84.4 %. The diagnostic accuracy parameters for breast MRI were sensitivity 93.8 %, specificity 82.8 %, PPV 88.2 %, NPV 92.3 %and accuracy 89.6 %. Area under the curve (AUC) of ROC was 0.96 for breast MRI and 0.88 for CESM. The Bland-Altman plots showed a mean difference of 0.7 mm with 95 % limits of agreement of 11.4 mm in tumor diameter measured using CESM and breast MRI. The differences of size measurement between CESM and breast MRI were significant, whereas no difference was observed between CESM and pathology as well as between breast MRI and pathology. The better correlation with pathological results was found in CESM than breast MRI. Our study demonstrates that CESM possesses better diagnostic performances than breast MRI in terms of diagnostic sensitivity and lesion size assessment. And CESM is a good alternative method of screening breast cancer in high-risk people.

  14. Pain empathy in schizophrenia: an fMRI study.

    Science.gov (United States)

    Horan, William P; Jimenez, Amy M; Lee, Junghee; Wynn, Jonathan K; Eisenberger, Naomi I; Green, Michael F

    2016-05-01

    Although it has been proposed that schizophrenia is characterized by impaired empathy, several recent studies found intact neural responses on tasks measuring the affective subdomain of empathy. This study further examined affective empathy in 21 schizophrenia outpatients and 21 healthy controls using a validated pain empathy paradigm with two components: (i) observing videos of people described as medical patients who were receiving a painful sound stimulation treatment; (ii) listening to the painful sounds (to create regions of interest). The observing videos component incorporated experimental manipulations of perspective taking (instructions to imagine 'Self' vs 'Other' experiencing pain) and cognitive appraisal (information about whether treatment was 'Effective' vs 'Not Effective'). When considering activation across experimental conditions, both groups showed similar dorsal anterior cingulate cortex (dACC) and anterior insula (AI) activation while merely observing others in pain. However, there were group differences associated with perspective taking: controls showed relatively greater dACC and AI activation for the Self vs Other contrast whereas patients showed relatively greater activation in these and additional regions for the Other vs Self contrast. Although patients demonstrated grossly intact neural activity while observing others in pain, they showed more subtle abnormalities when required to toggle between imagining themselves vs others experiencing pain. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  15. The approach to developmental dyslexia. The use of functional MRI studies

    International Nuclear Information System (INIS)

    Seki, Ayumi; Koeda, Tatsuya; Okada, Tomohisa; Sadato, Norihiro

    2004-01-01

    Developmental dyslexia is defined as a specific and significant impairment in reading ability that cannot be accounted for by any deficit in general intelligence or sensory acuity. It has been known that dyslexic children exhibit deficits for phonological awareness tasks, which require the ability to manipulate abstract phonological representations. A lower prevalence of dyslexia in Japanese suggests that the Japanese language may be more easily learned and manipulated by people with dyslexia. There are two supposable approaches to studying the mechanism of dyslexia using the functional MRI (fMRI). One is the study in healthy Japanese to investigate advantageous properties of Japanese related to less prevalence of dyslexia and the other is the comparative study in children to investigate the different cortical activity of dyslexia and normal readers. First, fMRI was used to investigate the neural substrates underlying phonological manipulation of the Japanese language. The posterior parts of the superior temporal sulcus (STS) were active during the auditory tasks, suggesting that phonological representations are manipulated in this area. In contrast, the intraparietal sulci (IPS), which have been implicated in visuospatial tasks, were active during the visual tasks, indicating that phonemic manipulation of kana'' letters is visuospatial. We suggest that because of the phonological and orthographical simplicities of the Japanese language, dyslexic children more easily learn the correspondence between letters and sounds. (author)

  16. Probing the Interoceptive Network by Listening to Heartbeats: An fMRI Study.

    Directory of Open Access Journals (Sweden)

    Nina I Kleint

    Full Text Available Exposure to cues of homeostatic relevance (i.e. heartbeats is supposed to increase the allocation of attentional resources towards the cue, due to its importance for self-regulatory, interoceptive processes. This functional magnetic resonance imaging (fMRI study aimed at determining whether listening to heartbeats is accompanied by activation in brain areas associated with interoception, particularly the insular cortex. Brain activity was measured with fMRI during cue-exposure in 36 subjects while listening to heartbeats vs. sinus tones. Autonomic markers (skin conductance and subjective measures of state and trait anxiety were assessed. Stimulation with heartbeat sounds triggered activation in brain areas commonly associated with the processing of interoceptive information, including bilateral insular cortices, the inferior frontal operculum, and the middle frontal gyrus. A psychophysiological interaction analysis indicated a functional connectivity between the middle frontal gyrus (seed region and bilateral insular cortices, the left amygdala and the supplementary motor area. The magnitude of neural activation in the right anterior insular cortex was positively associated with autonomic arousal. The present findings indicate that listening to heartbeats induced activity in areas of the interoception network as well as changes in psychophysiological arousal and subjective emotional experience. As this approach constitutes a promising method for studying interoception in the fMRI environment, a clinical application in anxiety prone populations should be addressed by future studies.

  17. Functional Laterality of Task-Evoked Activation in Sensorimotor Cortex of Preterm Infants: An Optimized 3 T fMRI Study Employing a Customized Neonatal Head Coil.

    Science.gov (United States)

    Scheef, Lukas; Nordmeyer-Massner, Jurek A; Smith-Collins, Adam Pr; Müller, Nicole; Stegmann-Woessner, Gaby; Jankowski, Jacob; Gieseke, Jürgen; Born, Mark; Seitz, Hermann; Bartmann, Peter; Schild, Hans H; Pruessmann, Klaas P; Heep, Axel; Boecker, Henning

    2017-01-01

    Functional magnetic resonance imaging (fMRI) in neonates has been introduced as a non-invasive method for studying sensorimotor processing in the developing brain. However, previous neonatal studies have delivered conflicting results regarding localization, lateralization, and directionality of blood oxygenation level dependent (BOLD) responses in sensorimotor cortex (SMC). Amongst the confounding factors in interpreting neonatal fMRI studies include the use of standard adult MR-coils providing insufficient signal to noise, and liberal statistical thresholds, compromising clinical interpretation at the single subject level. Here, we employed a custom-designed neonatal MR-coil adapted and optimized to the head size of a newborn in order to improve robustness, reliability and validity of neonatal sensorimotor fMRI. Thirteen preterm infants with a median gestational age of 26 weeks were scanned at term-corrected age using a prototype 8-channel neonatal head coil at 3T (Achieva, Philips, Best, NL). Sensorimotor stimulation was elicited by passive extension/flexion of the elbow at 1 Hz in a block design. Analysis of temporal signal to noise ratio (tSNR) was performed on the whole brain and the SMC, and was compared to data acquired with an 'adult' 8 channel head coil published previously. Task-evoked activation was determined by single-subject SPM8 analyses, thresholded at p lateralization of SMC activation, as found in children and adults, is already present in the newborn period.

  18. Is the Number of Different MRI Findings More Strongly Associated with Low Back Pain Than Single MRI Findings?

    DEFF Research Database (Denmark)

    Hancock, Mark J; Kjaer, Per; Kent, Peter

    2017-01-01

    STUDY DESIGN: A cross-sectional and longitudinal analysis using 2 different data sets OBJECTIVE.: To investigate if the number of different MRI findings present is more strongly associated with low back pain (LBP) than single MRI findings. SUMMARY OF BACKGROUND DATA: Most previous studies have....... The outcome for the cross-sectional study was presence of LBP during the last year. The outcome for the longitudinal study was days to recurrence of activity limiting LBP. In both data sets we created an aggregate score of the number of different MRI findings present in each individual and assessed...... investigated the associations between single MRI findings and back pain rather than investigating combinations of MRI findings. If different individuals have different pathoanatomic sources contributing to their pain, then combinations of MRI findings may be more strongly associated with LBP. METHODS...

  19. Conflict anticipation in alcohol dependence - A model-based fMRI study of stop signal task.

    Science.gov (United States)

    Hu, Sien; Ide, Jaime S; Zhang, Sheng; Sinha, Rajita; Li, Chiang-Shan R

    2015-01-01

    Our previous work characterized altered cerebral activations during cognitive control in individuals with alcohol dependence (AD). A hallmark of cognitive control is the ability to anticipate changes and adjust behavior accordingly. Here, we employed a Bayesian model to describe trial-by-trial anticipation of the stop signal and modeled fMRI signals of conflict anticipation in a stop signal task. Our goal is to characterize the neural correlates of conflict anticipation and its relationship to response inhibition and alcohol consumption in AD. Twenty-four AD and 70 age and gender matched healthy control individuals (HC) participated in the study. fMRI data were pre-processed and modeled with SPM8. We modeled fMRI signals at trial onset with individual events parametrically modulated by estimated probability of the stop signal, p(Stop), and compared regional responses to conflict anticipation between AD and HC. To address the link to response inhibition, we regressed whole-brain responses to conflict anticipation against the stop signal reaction time (SSRT). Compared to HC (54/70), fewer AD (11/24) showed a significant sequential effect - a correlation between p(Stop) and RT during go trials - and the magnitude of sequential effect is diminished, suggesting a deficit in proactive control. Parametric analyses showed decreased learning rate and over-estimated prior mean of the stop signal in AD. In fMRI, both HC and AD responded to p(Stop) in bilateral inferior parietal cortex and anterior pre-supplementary motor area, although the magnitude of response increased in AD. In contrast, HC but not AD showed deactivation of the perigenual anterior cingulate cortex (pgACC). Furthermore, deactivation of the pgACC to increasing p(Stop) is positively correlated with the SSRT in HC but not AD. Recent alcohol consumption is correlated with increased activation of the thalamus and cerebellum in AD during conflict anticipation. The current results highlight altered proactive

  20. Lung MRI at 1.5 and 3 Tesla: observer preference study and lesion contrast using five different pulse sequences.

    Science.gov (United States)

    Fink, Christian; Puderbach, Michael; Biederer, Juergen; Fabel, Michael; Dietrich, Olaf; Kauczor, Hans-Ulrich; Reiser, Maximilian F; Schönberg, Stefan O

    2007-06-01

    To compare the image quality and lesion contrast of lung MRI using 5 different pulse sequences at 1.5 T and 3 T. Lung MRI was performed at 1.5 T and 3 T using 5 pulse sequences which have been previously proposed for lung MRI: 3D volumetric interpolated breath-hold examination (VIBE), true fast imaging with steady-state precession (TrueFISP), half-Fourier single-shot turbo spin-echo (HASTE), short tau inversion recovery (STIR), T2-weighted turbo spin-echo (TSE). In addition to 4 healthy volunteers, 5 porcine lungs were examined in a dedicated chest phantom. Lung pathology (nodules and infiltrates) was simulated in the phantom by intrapulmonary and intrabronchial injections of agarose. CT was performed in the phantom for correlation. Image quality of the sequences was ranked in a side-by-side comparison by 3 blinded radiologists regarding the delineation of pulmonary and mediastinal anatomy, conspicuity of pulmonary nodules and infiltrates, and presence of artifacts. The contrast of nodules and infiltrates (CNODULES and CINFILTRATES) defined by the ratio of the signal intensities of the lesion and adjacent normal lung parenchyma was determined. There were no relevant differences regarding the preference for the individual sequences between both field strengths. TSE was the preferred sequence for the visualization of the mediastinum at both field strengths. For the visualization of lung parenchyma the observers preferred TrueFISP in volunteers and TSE in the phantom studies. At both field strengths VIBE achieved the best rating for the depiction of nodules, whereas HASTE was rated best for the delineation of infiltrates. TrueFISP had the fewest artifacts in volunteers, whereas STIR showed the fewest artifacts in the phantom. For all but the TrueFISP sequence the lesion contrast increased from 1.5 T to 3 T. At both field strengths VIBE showed the highest CNODULES (6.6 and 7.1) and HASTE the highest CINFILTRATES (6.1 and 6.3). The imaging characteristics of different

  1. ROCKETSHIP: a flexible and modular software tool for the planning, processing and analysis of dynamic MRI studies

    International Nuclear Information System (INIS)

    Barnes, Samuel R.; Ng, Thomas S. C.; Santa-Maria, Naomi; Montagne, Axel; Zlokovic, Berislav V.; Jacobs, Russell E.

    2015-01-01

    Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a promising technique to characterize pathology and evaluate treatment response. However, analysis of DCE-MRI data is complex and benefits from concurrent analysis of multiple kinetic models and parameters. Few software tools are currently available that specifically focuses on DCE-MRI analysis with multiple kinetic models. Here, we developed ROCKETSHIP, an open-source, flexible and modular software for DCE-MRI analysis. ROCKETSHIP incorporates analyses with multiple kinetic models, including data-driven nested model analysis. ROCKETSHIP was implemented using the MATLAB programming language. Robustness of the software to provide reliable fits using multiple kinetic models is demonstrated using simulated data. Simulations also demonstrate the utility of the data-driven nested model analysis. Applicability of ROCKETSHIP for both preclinical and clinical studies is shown using DCE-MRI studies of the human brain and a murine tumor model. A DCE-MRI software suite was implemented and tested using simulations. Its applicability to both preclinical and clinical datasets is shown. ROCKETSHIP was designed to be easily accessible for the beginner, but flexible enough for changes or additions to be made by the advanced user as well. The availability of a flexible analysis tool will aid future studies using DCE-MRI. A public release of ROCKETSHIP is available at (https://github.com/petmri/ROCKETSHIP)

  2. Collective Correlations of Brodmann Areas fMRI Study with RMT-Denoising

    Science.gov (United States)

    Burda, Z.; Kornelsen, J.; Nowak, M. A.; Porebski, B.; Sboto-Frankenstein, U.; Tomanek, B.; Tyburczyk, J.

    We study collective behavior of Brodmann regions of human cerebral cortex using functional Magnetic Resonance Imaging (fMRI) and Random Matrix Theory (RMT). The raw fMRI data is mapped onto the cortex regions corresponding to the Brodmann areas with the aid of the Talairach coordinates. Principal Component Analysis (PCA) of the Pearson correlation matrix for 41 different Brodmann regions is carried out to determine their collective activity in the idle state and in the active state stimulated by tapping. The collective brain activity is identified through the statistical analysis of the eigenvectors to the largest eigenvalues of the Pearson correlation matrix. The leading eigenvectors have a large participation ratio. This indicates that several Broadmann regions collectively give rise to the brain activity associated with these eigenvectors. We apply random matrix theory to interpret the underlying multivariate data.

  3. Unilateral occlusion of duplicated uterus with ipsilateral renal anomaly in young girls: a study with MRI

    International Nuclear Information System (INIS)

    Li, Y.W.; Shieh, C.P.; Chen, W.J.

    1995-01-01

    Twenty-four young girls (mean age 13.0 years) with unilateral occlusion of a duplicated uterus and ipsilateral renal agenesis, dysplasia or hypoplasia were studied with magnetic resonance imaging (MRI) following ultrasound examination. Hydrocolpos (n=4), hydrometrocolpos (n=2), hematocolpos (n=11), hematometrocolpos (n=5), hematocolpometra, hematosalpinx (n=3) and hematometra, hematosalpinx (n=1) were noted (two of these patients had presented with hydrocolpos and hematocolpos before and after the menarche). Twenty-two of these girls presented with ipsilateral renal agenesis (right 11, left 11) with ectopic ureters to Gartner's dust cysts (GDC) in two, in one renal hypoplasia and in one renal dysplasia with ectopic ureters to GDC. MRI offered specific images of the genital tract, showing the exact type of muellerian duct anomaly and providing high diagnostic accuracy. Such preoperative identification of a uterine anomaly, complemented with appropriate surgical intervention, can assist young girls in achieving normal fertility in the future. (orig.)

  4. A functional MRI study of language networks in left medial temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Yu Aihong; Wang Xiaoyi; Xu Guoqing; Li Yongjie; Qin Wen; Li Kuncheng; Wang, Yuping

    2011-01-01

    Purpose: The purpose of this study was to investigate the abnormality of language networks in left medial temporal lobe epilepsy (MTLE) using fMRI. Materials and methods: Eight patients with left MTLE and 15 healthy subjects were evaluated. An auditory semantic judgment (AJ) paradigm was used. The fMRI data were collected on a 3T MR system and analyzed by AFNI (analysis of functional neuroimages) to generate the activation map. Results: Behavioral data showed that the reaction time of the left MTLE patients was significantly longer than that of controls on the AJ task (t = -3.396, P < 0.05). The left MTLE patients also exhibited diffusively decreased activation in the AJ task. Right hemisphere dominance of Broca's and Wernicke's areas was demonstrated in left MTLE patients. Conclusions: Long-term activation of spikes in left MTLE patients results in language impairment, which is associated with an abnormality of the brain neural network.

  5. Preclinical animal acute toxicity studies of new developed MRI contrast agent based on gadolinium

    Science.gov (United States)

    Nam, I. F.; Zhuk, V. V.

    2015-04-01

    Acute toxicity test of new developed MRI contrast agent based on disodium salt of gadopentetic acid complex were carried out on Mus musculus and Sprague Dawley rats according to guidelines of preclinical studies [1]. Groups of six animals each were selected for experiment. Death and clinical symptoms of animals were recorded during 14 days. As a result the maximum tolerated dose (MTD) for female mice is 2.8 mM/kg of body weight, male mice - 1.4 mM/kg, female rats - 2.8 mM/kg, male rats - 5.6 mM/kg of body weight. No Observed Adverse Effect Dose (NOAEL) for female mice is 1.4 mM/kg, male mice - 0.7 mM/kg, male and female rats - 0.7 mM/kg. According to experimental data new developed MRI contrast agent based on Gd-DTPA complex is low-toxic.

  6. Positive Emotion Facilitates Cognitive Flexibility: An fMRI Study

    Directory of Open Access Journals (Sweden)

    Yanmei Wang

    2017-10-01

    Full Text Available Cognitive flexibility is the ability to switch rapidly between multiple goals. By using a task-switching paradigm, the present study investigated how positive emotion affected cognitive flexibility and the underlying neural mechanisms. After viewing pictures of different emotional valence (positive, negative, or neutral, participants discriminated whether a target digit in a specific color was odd or even. After a series of trials, the color of target stimuli was changed, i.e., the switch condition. Switch costs were measured by the increase of reaction times (RTs in the switch trials compared to those in the repeat trials. Behavior results indicated that switch costs significantly decreased in the positive emotional condition, and increased in the negative emotional condition, compared with those in the neutral condition. Imaging data revealed enhanced activation in the dorsal anterior cingulate cortex (dACC in switch trials than those in repeat trials. Moreover, the interaction between emotion (positive, negative, neutral and trial type (repeat vs. switch was significant. For switch trials, the activation of dACC decreased significantly in the positive condition, while increased significantly in the negative condition compared to neutral condition. By contrast, for repeat trials, no significant difference was observed for the activation of dACC among three emotional conditions. Our results showed that positive emotions could increase the cognitive flexibility and reduce the conflict by decreasing the activation of dACC.

  7. Laparoscopy After Previous Laparotomy

    Directory of Open Access Journals (Sweden)

    Zulfo Godinjak

    2006-11-01

    Full Text Available Following the abdominal surgery, extensive adhesions often occur and they can cause difficulties during laparoscopic operations. However, previous laparotomy is not considered to be a contraindication for laparoscopy. The aim of this study is to present that an insertion of Veres needle in the region of umbilicus is a safe method for creating a pneumoperitoneum for laparoscopic operations after previous laparotomy. In the last three years, we have performed 144 laparoscopic operations in patients that previously underwent one or two laparotomies. Pathology of digestive system, genital organs, Cesarean Section or abdominal war injuries were the most common causes of previouslaparotomy. During those operations or during entering into abdominal cavity we have not experienced any complications, while in 7 patients we performed conversion to laparotomy following the diagnostic laparoscopy. In all patients an insertion of Veres needle and trocar insertion in the umbilical region was performed, namely a technique of closed laparoscopy. Not even in one patient adhesions in the region of umbilicus were found, and no abdominal organs were injured.

  8. An MRI volumetric study for leg muscles in congenital clubfoot.

    Science.gov (United States)

    Ippolito, Ernesto; Dragoni, Massimiliano; Antonicoli, Marco; Farsetti, Pasquale; Simonetti, Giovanni; Masala, Salvatore

    2012-10-01

    To investigate both volume and length of the three muscle compartments of the normal and the affected leg in unilateral congenital clubfoot. Volumetric magnetic resonance imaging (VMRI) of the anterior, lateral and postero-medial muscular compartments of both the normal and the clubfoot leg was obtained in three groups of seven patients each, whose mean age was, respectively, 4.8 months, 11.1 months and 4.7 years. At diagnosis, all the unilateral congenital clubfeet had a Pirani score ranging from 4.5 to 5.5 points, and all of them had been treated according to a strict Ponseti protocol. All the feet had percutaneous lengthening of the Achilles tendon. A mean difference in both volume and length was found between the three muscular compartments of the leg, with the muscles of the clubfoot side being thinner and shorter than those of the normal side. The distal tendon of the tibialis anterior, peroneus longus and triceps surae (Achilles tendon) were longer than normal on the clubfoot side. Our study shows that the three muscle compartments of the clubfoot leg are thinner and shorter than normal in the patients of the three groups. The difference in the musculature volume of the postero-medial compartment between the normal and the affected side increased nine-fold from age group 2 to 3, while the difference in length increased by 20 %, thus, showing that the muscles of the postero-medial compartment tend to grow in both thickness and length much less than the muscles of the other leg compartments.

  9. Processes in arithmetic strategy selection: a fMRI study.

    Science.gov (United States)

    Taillan, Julien; Ardiale, Eléonore; Anton, Jean-Luc; Nazarian, Bruno; Félician, Olivier; Lemaire, Patrick

    2015-01-01

    This neuroimaging (functional magnetic resonance imaging) study investigated neural correlates of strategy selection. Young adults performed an arithmetic task in two different conditions. In both conditions, participants had to provide estimates of two-digit multiplication problems like 54 × 78. In the choice condition, participants had to select the better of two available rounding strategies, rounding-up (RU) strategy (i.e., doing 60 × 80 = 4,800) or rounding-down (RD) strategy (i.e., doing 50 × 70 = 3,500 to estimate product of 54 × 78). In the no-choice condition, participants did not have to select strategy on each problem but were told which strategy to use; they executed RU and RD strategies each on a series of problems. Participants also had a control task (i.e., providing correct products of multiplication problems like 40 × 50). Brain activations and performance were analyzed as a function of these conditions. Participants were able to frequently choose the better strategy in the choice condition; they were also slower when they executed the difficult RU than the easier RD. Neuroimaging data showed greater brain activations in right anterior cingulate cortex (ACC), dorso-lateral prefrontal cortex (DLPFC), and angular gyrus (ANG), when selecting (relative to executing) the better strategy on each problem. Moreover, RU was associated with more parietal cortex activation than RD. These results suggest an important role of fronto-parietal network in strategy selection and have important implications for our further understanding and modeling cognitive processes underlying strategy selection.

  10. Memory Deficits in Schizophrenia: A Selective Review of Functional Magnetic Resonance Imaging (fMRI Studies

    Directory of Open Access Journals (Sweden)

    Adrienne C. Lahti

    2013-06-01

    Full Text Available Schizophrenia is a complex chronic mental illness that is characterized by positive, negative and cognitive symptoms. Cognitive deficits are most predictive of long-term outcomes, with abnormalities in memory being the most robust finding. The advent of functional magnetic resonance imaging (fMRI has allowed exploring neural correlates of memory deficits in vivo. In this article, we will give a selective review of fMRI studies probing brain regions and functional networks that are thought to be related to abnormal memory performance in two memory systems prominently affected in schizophrenia; working memory and episodic memory. We revisit the classic “hypofrontality” hypothesis of working memory deficits and explore evidence for frontotemporal dysconnectivity underlying episodic memory abnormalities. We conclude that fMRI studies of memory deficits in schizophrenia are far from universal. However, the current literature does suggest that alterations are not isolated to a few brain regions, but are characterized by abnormalities within large-scale brain networks.

  11. Serial MRI and MRS studies with unusual findings in Rasmussen's encephalitis

    International Nuclear Information System (INIS)

    Tuerkdogan-Soezueer, D.; Oezek, M.M.; Pamir, M.N.; Sav, A.; Dincer, A.

    2000-01-01

    Rasmussen's syndrome is characterized by intractable seizures and progressive neuropsychiatric deterioration secondary to unilateral cortical inflammation and tissue destruction. Diagnosis of Rasmussen's syndrome in the early phase depends mainly on the clinical features. Neuroimaging and histopathologic examinations may not be specific during this period. We report a case of Rasmussen's syndrome followed by serial MRI and magnetic resonance spectroscopy (MRS) studies over a 3- to 16-month period. A healthy 6-year-old boy presented with focal motor seizures. An MRI study demonstrated prominent enlargement and T2 hyperintensity of the left mesial temporal lobe and perisylvian region. This early finding evolved to volume loss and later progressive atrophy of the ipsilateral hemisphere when epilepsia partialis continua occurred. Being aware of those early MRI features in a patient with increasing frequency of focal motor seizures should suggest Rasmussen's syndrome. In addition, we found prominently increased myoinositol concentration in atrophic cortex which might reflect increased gliosis in the late period of the disease. (orig.)

  12. Serial MRI and MRS studies with unusual findings in Rasmussen's encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Tuerkdogan-Soezueer, D. [Department of Pediatric Neurology, Institute of Neurological Sciences, Marmara University, Istanbul (Turkey); Oezek, M.M.; Pamir, M.N. [Department of Neurosurgery, Institute of Neurological Sciences, Marmara University, Istanbul (Turkey); Sav, A. [Department of Pathology, Institute of Neurological Sciences, Marmara University, Istanbul (Turkey); Dincer, A. [Radyomar MR Center, Istanbul (Turkey)

    2000-06-01

    Rasmussen's syndrome is characterized by intractable seizures and progressive neuropsychiatric deterioration secondary to unilateral cortical inflammation and tissue destruction. Diagnosis of Rasmussen's syndrome in the early phase depends mainly on the clinical features. Neuroimaging and histopathologic examinations may not be specific during this period. We report a case of Rasmussen's syndrome followed by serial MRI and magnetic resonance spectroscopy (MRS) studies over a 3- to 16-month period. A healthy 6-year-old boy presented with focal motor seizures. An MRI study demonstrated prominent enlargement and T2 hyperintensity of the left mesial temporal lobe and perisylvian region. This early finding evolved to volume loss and later progressive atrophy of the ipsilateral hemisphere when epilepsia partialis continua occurred. Being aware of those early MRI features in a patient with increasing frequency of focal motor seizures should suggest Rasmussen's syndrome. In addition, we found prominently increased myoinositol concentration in atrophic cortex which might reflect increased gliosis in the late period of the disease. (orig.)

  13. Study of cysticercosis in the fourth ventricle by CSF cinema MRI

    International Nuclear Information System (INIS)

    Wang Lianqing; Liu Lianxiang; Wu Jie; Wu Jing; Zhang Renshu; Wu Yujin

    1997-01-01

    Purpose: To evaluate the diagnostic value of cysticercosis in the fourth ventricle by CSF cinema MRI. Materials and methods: Nine patients with intraventricular cysticercosis in the fourth ventricle were studied. The diagnosis was confirmed by surgery in all cases. All of these patients were examined systematically before the operation and studied with CSF cinema MRI in mid sagittal section and finger-gated scan technique. Results: (1) The path of CSF flow was directly displayed. All cysticercosis presented as a filling defect, and a cyst with a smooth wall. (2) The ventricular compliance was normal in cysticercosis. (3) The cysticercosis in active stage was free in the fourth ventricle and could be rolled over, its shape might change slightly within a cardiac cycle. In the degenerative stage, its wall could adhere to the ependyma and obstruct the CSF flow. Conclusion: CSF cinema MRI can demonstrate the degree of obstruction and pattern of CSF flow in cysticercosis of the fourth ventricle, thereby providing useful information for proper management

  14. Studies on MRI diagnostic accuracy of invasion to body muscular layer and cervix of endometrial cancer

    International Nuclear Information System (INIS)

    Takemoto, Yumi; Fujiyoshi, Keizou; Takemoto, Shuji; Kawano, Kouichirou; Ohta, Shunichirou; Murakami, Fumihiro; Komai, Kan; Ushijima, Kimio; Kamura, Toshiharu

    2008-01-01

    This study was conducted to know usefulness of preoperative MRI to detect invasions of endometrial cancer to uterine body muscular layer and cervix. Subjects were 132 patients (median age of 57 y, pre- and post-menopause, 11.2 and 78.8%, respectively) with the cancer at stage I (66 cases) and >II in authors' facility, who had undergone the preoperative MRI with 1.5T Siemens machine by imaging with T1 and T2 weighted, Gd-enhanced T1 weighted, dynamic study and STIR. Imaging findings were compared with histopathological ones to assess the accuracy of imaging diagnosis. Positive predictive accuracy for muscular invasion was found to be as high as 95.5% and negative one, as low as 29.5%: especially, in pre-menopause group, tendency of underestimation for the invasion was thought notable. In contrast, negative accuracy was found low for cervical invasion and positive one, high: overestimation was possibly occurring. Thus, MRI diagnosis of those invasions should be seriously judged with careful consideration of menopause state. (R.T.)

  15. Resting-state fMRI study of patients with fragile X syndrome

    Science.gov (United States)

    Isanova, E.; Petrovskiy, E.; Savelov, A.; Yudkin, D.; Tulupov, A.

    2017-08-01

    The study aimed to assess the neural activity of different brain regions in patients with fragile X syndrome (FXS) and the healthy volunteers by resting-state functional magnetic resonance imaging (fMRI) on a 1.5 T MRI Achieva scanner (Philips). Results: The fMRI study showed a DMN of brain function in patients with FXS, as well as in the healthy volunteers. Furthermore, it was found that a default mode network of the brain in patients with FXS and healthy volunteers does not have statistically significant differences (p>0.05), which may indicate that the basal activity of neurons in patients with FXS is not reduced. In addition, we have found a significant (pright inferior parietal and right angular gyrus in the resting state in patients with FXS. Conclusion: New data of functional status of the brain in patients with FXS were received. The significant increase in the resting state functional connectivity within the right inferior parietal and right angular gyrus (p<0.001) in patients with FXS was found.

  16. Altered Structural and Functional Connectivity of Juvenile Myoclonic Epilepsy: An fMRI Study

    Directory of Open Access Journals (Sweden)

    Chengqing Zhong

    2018-01-01

    Full Text Available The aim of this study was to investigate the structural and functional connectivity (FC of juvenile myoclonic epilepsy (JME using resting state functional magnetic resonance imaging (rs-fMRI. High-resolution T1-weighted magnetic resonance imaging (MRI and rs-fMRI data were collected in 25 patients with JME and in 24 control subjects. A FC analysis was subsequently performed, with seeding at the regions that demonstrated between-group differences in gray matter volume (GMV. Then, the observed structural and FCs were associated with the clinical manifestations. The decreased GMV regions were found in the bilateral anterior cerebellum, the right orbital superior frontal gyrus, the left middle temporal gyrus, the left putamen, the right hippocampus, the bilateral caudate, and the right thalamus. The changed FCs were mainly observed in the motor-related areas and the cognitive-related areas. The significant findings of this study revealed an important role for the cerebellum in motor control and cognitive regulation in JME patients, which also have an effect on the activity of the occipital lobe. In addition, the changed FCs were related to the clinical features of JME patients. The current observations may contribute to the understanding of the pathogenesis of JME.

  17. Sensitivity and specificity of a new MRI method evaluating temporo-mandibular joint disc-condyle relationships: an in vivo study.

    Science.gov (United States)

    Benbelaïd, R; Fleiter, B

    2006-03-01

    The aim of this study was to evaluate sensitivity and specificity of a new method to locate temporo-mandibular joint (TMJ) disc using magnetic resonance imaging (MRI) and analyze disc-condyle relationships, in asymptomatic subjects and patients with disc displacement. Twenty-nine sagittal MRI of 16 subjects, 8 asymptomatic volunteers and 8 subjects with anterior disc displacement, were carried out during controlled opening from intercuspal position up to a 25 mm opening. Selected sections were analyzed with a graphic computerized system of coordinates. The total surface area (TS) of disc section was separated into anterior surface area (AS) and posterior surface area. Areas were determined by computer. Two trained examiners drew images at random. The reliability of AS/TS ratio index was evaluated in a previous study. AS/TS ratio sensitivity (Se) and specificity (Sp) were calculated closed mouth, 5 mm open and 25 mm open mouth. Best sensitivity (Se=0.63) and specificity (Sp=0.81) were obtained when MRI was realized with closed mouth and 25 mm open mouth. Lower sensitivity was observed when MRI was performed either with closed mouth (Se=0.54) or 25 mm open mouth (Se=0.18). Lower specificity was observed with 5 mm open mouth (Sp=0.68). In conclusion, it was confirmed as well that MRI of anterior disc displacement should be performed with closed mouth and opened mouth. Thus, further studies are required to assess disc displacement and mechanical alterations and to evaluate the risk of direct damage on TMJ tissues.

  18. Abnormal regional homogeneity in Parkinson's disease: a resting state fMRI study

    International Nuclear Information System (INIS)

    Li, Y.; Liang, P.; Jia, X.; Li, K.

    2016-01-01

    Aim: To examine the functional brain alterations in Parkinson's disease (PD) by measuring blood oxygenation level dependent (BOLD) functional MRI (fMRI) signals at rest while controlling for the structural atrophy. Materials and methods: Twenty-three PD patients and 20 age, gender, and education level matched normal controls (NC) were included in this study. Resting state fMRI and structural MRI data were acquired. The resting state brain activity was measured by the regional homogeneity (ReHo) method and the grey matter (GM) volume was attained by the voxel-based morphology (VBM) analysis. Two-sample t-test was then performed to detect the group differences with structural atrophy as a covariate. Results: VBM analysis showed GM volume reductions in the left superior frontal gyrus, left paracentral lobule, and left middle frontal gyrus in PD patients as compared to NC. There were widespread ReHo differences between NC and PD patients. Compared to NC, PD patients showed significant alterations in the motor network, including decreased ReHo in the right primary sensory cortex (S1), while increased ReHo in the left premotor area (PMA) and left dorsolateral prefrontal cortex (DLPFC). In addition, a cluster in the left superior occipital gyrus (SOG) also showed increased ReHo in PD patients. Conclusion: The current findings indicate that significant changes of ReHo in the motor and non-motor cortices have been detected in PD patients, independent of age, gender, education level, and structural atrophy. The present study thus suggests ReHo abnormalities as a potential biomarker for the diagnosis of PD and further provides insights into the biological mechanism of the disease. - Highlights: • Functional changes were found in PD patients independent of structural atrophy. • Both increased and decreased ReHo were observed in motor network regions in PD. • Increased ReHo was detected in visual association cortex for PD patients.

  19. Comparison of two brain tumor-localizing MRI agent. GD-BOPTA and GD-DTPA. MRI and ICP study of rat brain tumor model

    International Nuclear Information System (INIS)

    Zhang, T.; Matsumura, A.; Yamamoto, T.; Yoshida, F.; Nose, T.

    2000-01-01

    In this study, we compared the behavior of Gd-BOPTA as a brain tumor selective contrast agent with Gd-DTPA in a common dose of 0.1 mmol/kg. We performed a MRI study using those two agent as contrast material, and we measured tissue Gd-concentrations by ICP-AES. As a result, Gd-BOPTA showed a better MRI enhancement in brain tumor. ICP showed significantly greater uptake of Gd-BOPTA in tumor samples, at all time course peaked at 5 minutes after administration, Gd being retained for a longer time in brain tumor till 2 hours, without rapid elimination as Gd-DTPA. We conclude that Gd-BOPTA is a new useful contrast material for MR imaging in brain tumor and an effective absorption agent for neutron capture therapy for further research. (author)

  20. Comparison of {sup 18}F-FDG PET/MRI and MRI alone for whole-body staging and potential impact on therapeutic management of women with suspected recurrent pelvic cancer. A follow-up study

    Energy Technology Data Exchange (ETDEWEB)

    Sawicki, Lino M.; Kirchner, Julian; Schaarschmidt, Benedikt M.; Antoch, Gerald [University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf (Germany); Grueneisen, Johannes; Forsting, Michael; Umutlu, Lale [University Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Ruhlmann, Verena; Herrmann, Ken [University Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, Essen (Germany); Aktas, Bahriye [University Duisburg-Essen, Medical Faculty, Department of Obstetrics and Gynecology, Essen (Germany)

    2018-04-15

    To evaluate the diagnostic performance of {sup 18}F-FDG PET/MRI for whole-body staging and potential changes in therapeutic management of women with suspected recurrent pelvic cancer in comparison with MRI alone. Seventy-one consecutive women (54 ± 13 years, range: 25-80 years) with suspected recurrence of cervical (32), ovarian (26), endometrial (7), vulvar (4), and vaginal (2) cancer underwent PET/MRI including a diagnostic contrast-enhanced MRI protocol. PET/MRI and MRI datasets were separately evaluated regarding lesion count, localization, categorization (benign/malignant), and diagnostic confidence (3-point scale; 1-3) by two physicians. The reference standard was based on histopathology results and follow-up imaging. Diagnostic accuracy and proportions of malignant and benign lesions rated correctly were retrospectively compared using McNemar's chi{sup 2} test. Differences in diagnostic confidence were assessed by Wilcoxon test. Fifty-five patients showed cancer recurrence. PET/MRI correctly identified more patients with cancer recurrence than MRI alone (100% vs. 83.6%, p < 0.01). In contrast to PET/MRI, MRI alone missed 4/15 patients with pelvic recurrence and miscategorized 8/40 patients with distant metastases as having local recurrence only. Based on the reference standard, 241 lesions were detected in the study cohort (181 malignant, 60 benign). While PET/MRI provided correct identification of 181/181 (100%) malignant lesions, MRI alone correctly identified 135/181 (74.6%) malignant lesions, which was significantly less compared to PET/MRI (p < 0.001). PET/MRI offered superior diagnostic accuracy (99.2% vs. 79.3%, p < 0.001) and diagnostic confidence in the categorization of malignant lesions compared with MRI alone (2.7 ± 0.5 vs. 2.4 ± 0.7, p < 0.001). PET/MRI demonstrates excellent diagnostic performance and outperforms MRI alone for whole-body staging of women with suspected recurrent pelvic cancer, indicating potential changes in therapy

  1. MRI in psychiatry

    International Nuclear Information System (INIS)

    Mulert, Christoph; Shenton, Martha E.

    2014-01-01

    This is the first comprehensive textbook on the use of MRI in psychiatry covering imaging techniques, brain systems and a review of findings in different psychiatric disorders. The book is divided into three sections, the first of which covers in detail all the major MRI-based methodological approaches available today, including fMRI, EEG-fMRI, DTI, and MR spectroscopy. In addition, the role of MRI in imaging genetics and combined brain stimulation and imaging is carefully explained. The second section provides an overview of the different brain systems that are relevant for psychiatric disorders, including the systems for perception, emotion, cognition, and reward. The final part of the book presents the MRI findings that are obtained in all the major psychiatric disorders using the previously discussed techniques. Numerous carefully chosen images support the informative text, making this an ideal reference work for all practitioners and trainees with an interest in this flourishing field.

  2. MRI in psychiatry

    Energy Technology Data Exchange (ETDEWEB)

    Mulert, Christoph [UKE, Hamburg (Germany). Psychiatry Neuroimaging Branch; Shenton, Martha E. (ed.) [Harvard Medical School, Boston, MA (United States). Dept. of Psychiatry and Radiology

    2014-07-01

    This is the first comprehensive textbook on the use of MRI in psychiatry covering imaging techniques, brain systems and a review of findings in different psychiatric disorders. The book is divided into three sections, the first of which covers in detail all the major MRI-based methodological approaches available today, including fMRI, EEG-fMRI, DTI, and MR spectroscopy. In addition, the role of MRI in imaging genetics and combined brain stimulation and imaging is carefully explained. The second section provides an overview of the different brain systems that are relevant for psychiatric disorders, including the systems for perception, emotion, cognition, and reward. The final part of the book presents the MRI findings that are obtained in all the major psychiatric disorders using the previously discussed techniques. Numerous carefully chosen images support the informative text, making this an ideal reference work for all practitioners and trainees with an interest in this flourishing field.

  3. Neural evidence for the use of digit-image mnemonic in a superior memorist: An fMRI study

    Directory of Open Access Journals (Sweden)

    Li-Jun eYin

    2015-03-01

    Full Text Available Some superior memorists demonstrated exceptional memory for reciting a large body of information. The underlying neural correlates, however, are seldom addressed. C.L., the current holder of Guinness World Record for reciting 67,890 digits in π, participated in this functional magnetic resonance imaging (fMRI study. Thirteen participants without any mnemonics training were included as controls. Our previous studies suggested that C.L. used a digit-image mnemonic in studying and recalling lists of digits, namely associating 2-digit groups of ‘00’ to ‘99’ with images and generating vivid stories out of them (Hu, Ericsson, Yang & Lu, 2009. Thus, 2-digit condition was included, with 1-digit numbers and letters as control conditions. We hypothesized that 2-digit condition in C.L. should elicit the strongest activity in the brain regions which are associated with his mnemonic. Functional MRI results revealed that bilateral frontal poles (FPs, BA10, left superior parietal lobule (SPL, left premotor cortex (PMC, and left dorsolateral prefrontal cortex (DLPFC, were more engaged in both the study and recall phase of 2-digit condition for C.L. relative to controls. Moreover, the left middle/inferior frontal gyri (M/IFG and intraparietal sulci (IPS were less engaged in the study phase of 2-digit condition for C.L. (vs. controls. These results suggested that C.L. relied more on brain regions that are associated with episodic memory other than verbal rehearsal while he used his mnemonic strategies. This study supported theoretical accounts of restructured cognitive mechanisms for the acquisition of superior memory performance.

  4. [fMRI study of the dominant hemisphere for language in patients with brain tumor].

    Science.gov (United States)

    Buklina, S B; Podoprigora, A E; Pronin, I N; Shishkina, L V; Boldyreva, G N; Bondarenko, A A; Fadeeva, L M; Kornienko, V N; Zhukov, V Iu

    2013-01-01

    Paper describes a study of language lateralization of patients with brain tumors, measured by preoperative functional magnetic resonance imaging (fMRI) and comparison results with tumor histology and profile of functional asymmetry. During the study 21 patient underwent fMRI scan. 15 patients had a tumor in the left and 6 in the right hemisphere. Tumors were localized mainly in the frontal, temporal and fronto-temporal regions. Histological diagnosis in 8 cases was malignant Grade IV, in 13 cases--Grade I-III. fMRI study was perfomed on scanner "Signa Exite" with a field strength of 1.5 As speech test reciting the months of the year in reverse order was used. fMRI scan results were compared with the profile of functional asymmetry, which was received with the results of questionnaire Annette and dichotic listening test. Broca's area was found in 7 cases in the left hemisphere, 6 had a tumor Grade I-III. And one patient with glioblastoma had a tumor of the right hemisphere. Broca's area in the right hemisphere was found in 3 patients (2 patients with left sided tumor, and one with right-sided tumor). One patient with left-sided tumor had mild motor aphasia. Bilateral activation in both hemispheres of the brain was observed in 6 patients. All of them had tumor Grade II-III of the left hemisphere. Signs of left-handedness were revealed only in half of these patients. Broca's area was not found in 4 cases. All of them had large malignant tumors Grade IV. One patient couldn't handle program of the research. Results of fMRI scans, questionnaire Annette and dichotic listening test frequently were not the same, which is significant. Bilateral activation in speech-loads may be a reflection of brain plasticity in cases of long-growing tumors. Thus it's important to consider the full range of clinical data in studying the problem of the dominant hemisphere for language.

  5. Establishment of atherosclerotic model and USPIO enhanced MRI techniques study in rabbits

    International Nuclear Information System (INIS)

    Li Yonggang; Zhu Mo; Dai Yinyu; Chen Jianhua; Guo Liang; Ni Jiankun

    2010-01-01

    Objective: To explore the methods of establishment of atherosclerotic model and USPIO enhanced MRI techniques in rabbits. Methods: Thirty New Zealand male rabbits were divided randomly into two groups: 20 animals in the experiment group, 10 animals in the control group. Animal model of atherosclerosis was induced with aortic balloon endothelial injury and high-fat diet feeding. There was no intervention with the rabbits in control group. MRI examination included plan scan, USPIO enhanced black-blood sequences and white-blood sequence. The features of the plaques was analyzed in the experimental group and the effection on the image quality of different coils, sequences and parameters and a statistical study was also analyzed. Results: Animal model of atherosclerosis was successfully made in 12 rabbits and most plaques located in the abdomen aorta. There were 86 plaques within the scanning scope among which 67 plaques were positive to the Prussian blue staining. The image quality of knee joint coil was better than that of other coils. Although there was no difference in the detection of numbers of AS plaques between USPIO enhanced black-blood sequences and white-blood sequence (P > 0.05), blackblood sequences was superior to white-blood sequence in the demonstration of the components of plaque. Conclusion: The method of aortic balloon endothelial injury and high-fat diet feeding can easily establish the AS model in rabbits with a shorter period and it may be used for controlling the location of the plaques. USPIO enhanced MRI sequences has high sensitivity in the detection of the AS plauqes and can reveal the component of AS plaques. The optimization of MRI techniques is very important in the improvement of the image quality and the detection of the plaques. (authors)

  6. Manual and computerized measurement of coronal vertebral inclination on MRI images: A pilot study

    International Nuclear Information System (INIS)

    Vrtovec, T.; Likar, B.; Pernuš, F.

    2013-01-01

    Aim: A pilot study that presents a systematic approach for evaluating the variability of manual and computerized measurements of coronal vertebral inclination (CVI) on images acquired by magnetic resonance imaging (MRI). Materials and methods: Three observers identified the vertebral body corners of 28 vertebrae on two occasions on two-dimensional (2D) coronal MRI cross-sections, which served to evaluate CVI using six manual measurements (superior and inferior tangents, left and right tangents, mid-endplate and mid-wall lines). Computerized measurements were performed by evaluating CVI from the symmetry of vertebral anatomical structures of the same 28 vertebrae in 2D coronal MRI cross-sections and in three-dimensional (3D) MRI images. Results: In terms of standard deviation (SD), the mid-endplate lines proved to be the manual measurements with the lowest intra- (1.0° SD) and interobserver (1.4° SD) variability. The computerized measurements in 3D yielded even lower intra- (0.8° SD) and interobserver (1.3° SD) variability. The strongest inter-method agreement (1.2° SD) was found among lines parallel to vertebral endplates (superior tangents, inferior tangents, mid-endplate lines). The computerized measurements in 3D were most in agreement with the mid-endplate lines (1.9° SD). The estimated intra- and interobserver variabilities of standard Cobb angle measurements were equal to 1.6° SD and 2.5° SD, respectively, for manual measurements, and to 1.1° SD and 1.8° SD, respectively, for computerized measurements. Conclusion: The mid-endplate lines proved to be the most reproducible and reliable manual CVI measurements. Computerized CVI measurements based on the evaluation of the symmetry of vertebral anatomical structures in 3D were more reproducible and reliable than manual measurements

  7. Body growth and brain development in premature babies: an MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Tzarouchi, Loukia C.; Zikou, Anastasia; Kosta, Paraskevi; Argyropoulou, Maria I. [University of Ioannina, Department of Radiology, Medical School, Ioannina (Greece); Drougia, Aikaterini; Andronikou, Styliani [University of Ioannina, Intensive Care Unit, Child Health Department, Medical School, Ioannina (Greece); Astrakas, Loukas G. [University of Ioannina, Department of Medical Physics, Medical School, Ioannina (Greece)

    2014-03-15

    Prematurity and intrauterine growth restriction are associated with neurodevelopmental disabilities. To assess the relationship between growth status and regional brain volume (rBV) and white matter microstructure in premature babies at around term-equivalent age. Premature infants (n= 27) of gestational age (GA): 29.8 ± 2.1 weeks, with normal brain MRI scans were studied at corrected age: 41.2 ± 1.4 weeks. The infants were divided into three groups: 1) appropriate for GA at birth and at the time of MRI (AGA), 2) small for GA at birth with catch-up growth at the time of MRI (SGA{sub a}) and 3) small for GA at birth with failure of catch-up growth at the time of MRI (SGA{sub b}). The T1-weighted images were segmented into 90 rBVs using the SPM8/IBASPM and differences among groups were assessed. Fractional anisotropy (FA) was measured bilaterally in 15 fiber tracts and its relationship to GA and somatometric measurements was explored. Lower rBV was observed in SGA{sub b} in superior and anterior brain areas. A positive correlation was demonstrated between FA and head circumference and body weight. Body weight was the only significant predictor for FA (P< 0.05). In premature babies, catch-up growth is associated with regional brain volume catch-up at around term-equivalent age, starting from the brain areas maturing first. Body weight seems to be a strong predictor associated with WM microstructure in brain areas related to attention, language, cognition, memory and executing functioning. (orig.)

  8. Blood-brain barrier permeability and monocyte infiltration in experimental allergic encephalomyelitis: a quantitative MRI study.

    Science.gov (United States)

    Floris, S; Blezer, E L A; Schreibelt, G; Döpp, E; van der Pol, S M A; Schadee-Eestermans, I L; Nicolay, K; Dijkstra, C D; de Vries, H E

    2004-03-01

    be monitored on-line with MRI using USPIOs and Gd-DTPA as contrast agents. These studies also implicate that USPIOs are a valuable tool to visualize monocyte infiltration in vivo and quantitatively assess the efficacy of new therapeutics like lovastatin.

  9. Body growth and brain development in premature babies: an MRI study

    International Nuclear Information System (INIS)

    Tzarouchi, Loukia C.; Zikou, Anastasia; Kosta, Paraskevi; Argyropoulou, Maria I.; Drougia, Aikaterini; Andronikou, Styliani; Astrakas, Loukas G.

    2014-01-01

    Prematurity and intrauterine growth restriction are associated with neurodevelopmental disabilities. To assess the relationship between growth status and regional brain volume (rBV) and white matter microstructure in premature babies at around term-equivalent age. Premature infants (n= 27) of gestational age (GA): 29.8 ± 2.1 weeks, with normal brain MRI scans were studied at corrected age: 41.2 ± 1.4 weeks. The infants were divided into three groups: 1) appropriate for GA at birth and at the time of MRI (AGA), 2) small for GA at birth with catch-up growth at the time of MRI (SGA a ) and 3) small for GA at birth with failure of catch-up growth at the time of MRI (SGA b ). The T1-weighted images were segmented into 90 rBVs using the SPM8/IBASPM and differences among groups were assessed. Fractional anisotropy (FA) was measured bilaterally in 15 fiber tracts and its relationship to GA and somatometric measurements was explored. Lower rBV was observed in SGA b in superior and anterior brain areas. A positive correlation was demonstrated between FA and head circumference and body weight. Body weight was the only significant predictor for FA (P< 0.05). In premature babies, catch-up growth is associated with regional brain volume catch-up at around term-equivalent age, starting from the brain areas maturing first. Body weight seems to be a strong predictor associated with WM microstructure in brain areas related to attention, language, cognition, memory and executing functioning. (orig.)

  10. Brain Abnormalities in Congenital Fibrosis of the Extraocular Muscles Type 1: A Multimodal MRI Imaging Study.

    Directory of Open Access Journals (Sweden)

    Wen Miao

    Full Text Available To explore the possible brain structural and functional alterations in congenital fibrosis of extraocular muscles type 1 (CFEOM1 patients using multimodal MRI imaging.T1-weighted, diffusion tensor images and functional MRI data were obtained from 9 KIF21A positive patients and 19 age- and gender-matched healthy controls. Voxel based morphometry and tract based spatial statistics were applied to the T1-weighted and diffusion tensor images, respectively. Amplitude of low frequency fluctuations and regional homogeneity were used to process the functional MRI data. We then compared these multimodal characteristics between CFEOM1 patients and healthy controls.Compared with healthy controls, CFEOM1 patients demonstrated increased grey matter volume in bilateral frontal orbital cortex and in the right temporal pole. No diffusion indices changes were detected, indicating unaffected white matter microstructure. In addition, from resting state functional MRI data, trend of amplitude of low-frequency fluctuations increases were noted in the right inferior parietal lobe and in the right frontal cortex, and a trend of ReHo increase (p<0.001 uncorrected in the left precentral gyrus, left orbital frontal cortex, temporal pole and cingulate gyrus.CFEOM1 patients had structural and functional changes in grey matter, but the white matter was unaffected. These alterations in the brain may be due to the abnormality of extraocular muscles and their innervating nerves. Future studies should consider the possible correlations between brain morphological/functional findings and clinical data, especially pertaining to eye movements, to obtain more precise answers about the role of brain area changes and their functional consequence in CFEOM1.

  11. Brain Abnormalities in Congenital Fibrosis of the Extraocular Muscles Type 1: A Multimodal MRI Imaging Study.

    Science.gov (United States)

    Miao, Wen; Man, Fengyuan; Wu, Shaoqin; Lv, Bin; Wang, Zhenchang; Xian, Junfang; Sabel, Bernhard A; He, Huiguang; Jiao, Yonghong

    2015-01-01

    To explore the possible brain structural and functional alterations in congenital fibrosis of extraocular muscles type 1 (CFEOM1) patients using multimodal MRI imaging. T1-weighted, diffusion tensor images and functional MRI data were obtained from 9 KIF21A positive patients and 19 age- and gender-matched healthy controls. Voxel based morphometry and tract based spatial statistics were applied to the T1-weighted and diffusion tensor images, respectively. Amplitude of low frequency fluctuations and regional homogeneity were used to process the functional MRI data. We then compared these multimodal characteristics between CFEOM1 patients and healthy controls. Compared with healthy controls, CFEOM1 patients demonstrated increased grey matter volume in bilateral frontal orbital cortex and in the right temporal pole. No diffusion indices changes were detected, indicating unaffected white matter microstructure. In addition, from resting state functional MRI data, trend of amplitude of low-frequency fluctuations increases were noted in the right inferior parietal lobe and in the right frontal cortex, and a trend of ReHo increase (pleft precentral gyrus, left orbital frontal cortex, temporal pole and cingulate gyrus. CFEOM1 patients had structural and functional changes in grey matter, but the white matter was unaffected. These alterations in the brain may be due to the abnormality of extraocular muscles and their innervating nerves. Future studies should consider the possible correlations between brain morphological/functional findings and clinical data, especially pertaining to eye movements, to obtain more precise answers about the role of brain area changes and their functional consequence in CFEOM1.

  12. Brain Abnormalities in Congenital Fibrosis of the Extraocular Muscles Type 1: A Multimodal MRI Imaging Study

    Science.gov (United States)

    Wu, Shaoqin; Lv, Bin; Wang, Zhenchang; Xian, Junfang; Sabel, Bernhard A.; He, Huiguang; Jiao, Yonghong

    2015-01-01

    Purpose To explore the possible brain structural and functional alterations in congenital fibrosis of extraocular muscles type 1 (CFEOM1) patients using multimodal MRI imaging. Methods T1-weighted, diffusion tensor images and functional MRI data were obtained from 9 KIF21A positive patients and 19 age- and gender- matched healthy controls. Voxel based morphometry and tract based spatial statistics were applied to the T1-weighted and diffusion tensor images, respectively. Amplitude of low frequency fluctuations and regional homogeneity were used to process the functional MRI data. We then compared these multimodal characteristics between CFEOM1 patients and healthy controls. Results Compared with healthy controls, CFEOM1 patients demonstrated increased grey matter volume in bilateral frontal orbital cortex and in the right temporal pole. No diffusion indices changes were detected, indicating unaffected white matter microstructure. In addition, from resting state functional MRI data, trend of amplitude of low-frequency fluctuations increases were noted in the right inferior parietal lobe and in the right frontal cortex, and a trend of ReHo increase (pleft precentral gyrus, left orbital frontal cortex, temporal pole and cingulate gyrus. Conclusions CFEOM1 patients had structural and functional changes in grey matter, but the white matter was unaffected. These alterations in the brain may be due to the abnormality of extraocular muscles and their innervating nerves. Future studies should consider the possible correlations between brain morphological/functional findings and clinical data, especially pertaining to eye movements, to obtain more precise answers about the role of brain area changes and their functional consequence in CFEOM1. PMID:26186732

  13. Study of physiology of visual cortex activated by rotating grating with functional MRI

    International Nuclear Information System (INIS)

    Liang Ping; Shao Qing; Zhang Zhiqiang; Lu Guangming

    2004-01-01

    Objective: To research the physiology of visual cortex activated by rotating grating with functional-MRI (fMRI), and to identify the components of the activation. Methods: Functional MRI was performed in 9 healthy volunteers by using GRE-EPI sequences on a 1.5 T MR scanner. In the block designing, rotating grating, static grating, and luminance were plotted as task states, while static grating, luminance, and darkness were set as control states. The stimuli tasks included six steps. Imaging processing and statistical analysis was carried out off-line using SPM99 in single-subject method. Results: Some respective areas of visual cortex were activated by the various stimuli information supplied by rotating grating. The strong activation in the middle of occipital lobe located at primary vision area was related to the stimuli of white luminance. Its average maximum points were at 13, -98, -2 and 11, -100, -41 The bilateral activations of Brodmann 19th area located at MT area were related to visual motion perception. Its average maximum points were at 46, -72, -2 and -44, -74, 0. The mild activation in the middle of occipital lobe was related to form perception. Its average maximum points were at -12, -98, -6 and -16, -96, -6. Conclusion: The plotting of control state is important in bock design. The effective visual information of rotating grating includes components of luminance, visual motion perception, and form perception. FMRI has potential as a tool for studying the basic physiology of visual cortex. (authors)

  14. The Use of Functional MRI to Study Appetite Control in the CNS

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    Akila De Silva

    2012-01-01

    Full Text Available Functional magnetic resonance imaging (fMRI has provided the opportunity to safely investigate the workings of the human brain. This paper focuses on its use in the field of human appetitive behaviour and its impact in obesity research. In the present absence of any safe or effective centrally acting appetite suppressants, a better understanding of how appetite is controlled is vital for the development of new antiobesity pharmacotherapies. Early functional imaging techniques revealed an attenuation of brain reward area activity in response to visual food stimuli when humans are fed—in other words, the physiological state of hunger somehow increases the appeal value of food. Later studies have investigated the action of appetite modulating hormones on the fMRI signal, showing how the attenuation of brain reward region activity that follows feeding can be recreated in the fasted state by the administration of anorectic gut hormones. Furthermore, differences in brain activity between obese and lean individuals have provided clues about the possible aetiology of overeating. The hypothalamus acts as a central gateway modulating homeostatic and nonhomeostatic drives to eat. As fMRI techniques constantly improve, functional data regarding the role of this small but hugely important structure in appetite control is emerging.

  15. Functional versus Nonfunctional Rehabilitation in Chronic Ischemic Stroke: Evidences from a Randomized Functional MRI Study

    Directory of Open Access Journals (Sweden)

    Maristela C. X. Pelicioni

    2016-01-01

    Full Text Available Motor rehabilitation of stroke survivors may include functional and/or nonfunctional strategy. The present study aimed to compare the effect of these two rehabilitation strategies by means of clinical scales and functional Magnetic Resonance Imaging (fMRI. Twelve hemiparetic chronic stroke patients were selected. Patients were randomly assigned a nonfunctional (NFS or functional (FS rehabilitation scheme. Clinical scales (Fugl-Meyer, ARA test, and modified Barthel and fMRI were applied at four moments: before rehabilitation (P1 and immediately after (P2, 1 month after (P3, and three months after (P4 the end of rehabilitation. The NFS group improved significantly and exclusively their Fugl-Meyer scores at P2, P3, and P4, when compared to P1. On the other hand, the FS group increased significantly in Fugl-Meyer at P2, when compared to P1, and also in their ARA and Barthel scores. fMRI inspection at the individual level revealed that both rehabilitation schemes most often led to decreased activation sparseness, decreased activity of contralesional M1, increased asymmetry of M1 activity to the ipsilesional side, decreased perilesional activity, and decreased SMA activity. Increased M1 asymmetry with rehabilitation was also confirmed by Lateralization Indexes. Our clinical analysis revealed subtle differences between FS and NFS.

  16. Integration of fMRI, NIROT and ERP for studies of human brain function.

    Science.gov (United States)

    Gore, John C; Horovitz, Silvina G; Cannistraci, Christopher J; Skudlarski, Pavel

    2006-05-01

    Different methods of assessing human brain function possess specific advantages and disadvantages compared to others, but it is believed that combining different approaches will provide greater information than can be obtained from each alone. For example, functional magnetic resonance imaging (fMRI) has good spatial resolution but poor temporal resolution, whereas the converse is true for electrophysiological recordings (event-related potentials or ERPs). In this review of recent work, we highlight a novel approach to combining these modalities in a manner designed to increase information on the origins and locations of the generators of specific ERPs and the relationship between fMRI and ERP signals. Near infrared imaging techniques have also been studied as alternatives to fMRI and can be readily integrated with simultaneous electrophysiological recordings. Each of these modalities may in principle be also used in so-called steady-state acquisitions in which the correlational structure of signals from the brain may be analyzed to provide new insights into brain function.

  17. Brain Activities Associated with Graphic Emoticons: An fMRI Study

    Science.gov (United States)

    Yuasa, Masahide; Saito, Keiichi; Mukawa, Naoki

    In this paper, we describe the brain activities that are associated with graphic emoticons by using functional MRI (fMRI). We use various types of faces from abstract to photorealistic in computer network applications. A graphics emoticon is an abstract face in communication over computer network. In this research, we created various graphic emoticons for the fMRI study and the graphic emoticons were classified according to friendliness and level of arousal. We investigated the brain activities of participants who were required to evaluate the emotional valence of the graphic emoticons (happy or sad). The experimental results showed that not only the right inferior frontal gyrus and the cingulate gyrus, but also the inferior and middle temporal gyrus and the fusiform gyrus, were found to be activated during the experiment. Forthermore, it is possible that the activation of the right inferior frontal gyrus and the cingulate gyrus is related to the type of abstract face. Since the inferior and middle temporal gyrus were activated, even though the graphic emoticons are static, we may perceive graphic emoticons as dynamic and living agents. Moreover, it is believed that text and graphics emoticons play an important role in enriching communication among users.

  18. A comparative study of single and multiple hand tasks using functional MRI

    International Nuclear Information System (INIS)

    Shin, Byung Suck; Lee, Ho Kyu; Park, Sung Tae; Kim, Dong Eun; Lee, Myung Jun; Choi, Choong Gon; Kim, Jae Kyun; Suh, Dae Chul; Lim, Tae Hwan

    1998-01-01

    The purpose of this study is to assess, using functional MRI and by comparing activated motor sensory areas, the independence of brain activation during single and alternative multiple hand tasks. The subjects were six healthy volunteers. Using at 1.5T Siemens system and single shot FID-EPI sequencing (T2 weighted image; TR/TE 0.96 msec/ 61msec, flip angle 90 deg, matrix size 96 x 128, slice thickness/gap 5 mm/0.8 mm, FOV 200 mm) and T1-weighted anatomic images, functional MRI was performed. The paradigm of motor tasks consisted of appositional finger movements; the first involved the separate use of the right, left, and both hands in sequence. Using cross-correlation method (threshold : 0.6) and fMRI analysis software (stimulate 5.0), functional images were obtained. The activated area of brain cortex, the number of pixel, the average percentage change in signal intensity, and correlation of the time-signal intensity curve in the activated motor area were analysed and compared between the two task groups. Statistical analysis involved the use of Wilcoxon signed-rank test. Brain activation did not differ according to whether the motor task was single or alternative. We therefore suggest that during multiple stimuli, the relevant functional area and neuronal column are activated independently. (author). 19 refs., 2 tabs., 3 figs

  19. Radioimmunotherapy with Y-90-epratuzumab in patients with previously treated B-cell lymphoma. A fractionated dose-escalation study

    International Nuclear Information System (INIS)

    Linden, O.; Cavallin-Stahl, E.; Tennvall, J.; Hindorf, C.; Olsson, T.; Strand, S.E.; Stenberg, L.; Wingardh, K.

    2002-01-01

    Aim: Fractionated RIT may improve outcome by decreasing heterogeneity in absorbed dose and by increasing therapeutic window. The humanised anti-CD22 antibody, Epratuzumab, (Immunomedics, Inc., Morris Plains, NJ) can be given repeatedly with minimal risk of neutralising Ab (HAHA), making fractionated treatment with 90 Y-labelled epratuzumab possible. Materials and Methods: Patients with previously treated B-cell lymphoma received increasing number (2-4) of weekly infusions of 90 Y-epratuzumab. Patients received either 185 MBq/m 2 per infusion (group A), or, if they had a history of high-dose chemotherapy with stem-cell rescue, 92.5 MBq/m 2 per infusion (group B). The first infusion included 150 MBq of 111 Indium for scintigraphic verification of tumour targeting and dosimetry. 1.5 mg/kg epratuzumab was administered with each infusion. The treatment could be repeated once after 3 m. Results: Of 23 patients, 16 in group A and 6 in group B were evaluable for response. The RR in group A was 62% objective response (OR) and 25% CR/CRu. One patient in group B showed OR. OR was seen in aggressive and indolent lymphoma. Response was also long-lasting and event-free survival of patients showing CR/CRu was 14 to 25+ months. In group A all seven patient, receiving three infusions, showed less than grade 3 platelet and neutrophil toxicity, except for two patients suffering grade 3 neutropenia. Of five patients with 4 weekly infusions there were two patients with dose-limiting haematological toxicity (DLT), both recently treated with high dose cytosar before RIT. With criteria used the maximal tolerated dose was three infusions 185 MBq/m 2 . In group B no patient suffered DLT and one patient exhibited OR. Seven patients were retreated after 3 months with minor toxicity, but improvement in OR in two cases. No patient has developed HAHA. CD22 expression on tumour cells, as assessed by flow cytometry, is available in 18 of 22 patients. In group A, seven of eight patients with

  20. The diagnostic value of 18F-FDG-PET/CT and MRI in suspected vertebral osteomyelitis - a prospective study.

    Science.gov (United States)

    Kouijzer, Ilse J E; Scheper, Henk; de Rooy, Jacky W J; Bloem, Johan L; Janssen, Marcel J R; van den Hoven, Leon; Hosman, Allard J F; Visser, Leo G; Oyen, Wim J G; Bleeker-Rovers, Chantal P; de Geus-Oei, Lioe-Fee

    2018-05-01

    The aim of this study was to determine the diagnostic value of 18 F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) and magnetic resonance imaging (MRI) in diagnosing vertebral osteomyelitis. From November 2015 until December 2016, 32 patients with suspected vertebral osteomyelitis were prospectively included. All patients underwent both 18 F-FDG-PET/CT and MRI within 48 h. All images were independently reevaluated by two radiologists and two nuclear medicine physicians who were blinded to each others' image interpretation. 18 F-FDG-PET/CT and MRI were compared to the clinical diagnosis according to international guidelines. For 18 F-FDG-PET/CT, sensitivity, specificity, PPV, and NPV in diagnosing vertebral osteomyelitis were 100%, 83.3%, 90.9%, and 100%, respectively. For MRI, sensitivity, specificity, PPV, and NPV were 100%, 91.7%, 95.2%, and 100%, respectively. MRI detected more epidural/spinal abscesses. An important advantage of 18 F-FDG-PET/CT is the detection of metastatic infection (16 patients, 50.0%). 18 F-FDG-PET/CT and MRI are both necessary techniques in diagnosing vertebral osteomyelitis. An important advantage of 18 F-FDG-PET/CT is the visualization of metastatic infection, especially in patients with bacteremia. MRI is more sensitive in detection of small epidural abscesses.

  1. Dynamic contrast-enhanced MRI examination of atherosclerotic plaques: an animal study using rabbit model

    International Nuclear Information System (INIS)

    Li Mingli; Sun Jie; Chang Xiaoyan; Jin Zhengyu

    2011-01-01

    Objective: The enhanced patterns of atherosclerotic plaque on dynamic contrast- enhanced MRI have not been well studied. The aim of this study was to explore the patterns of plaque enhancement and their underlying mechanism by using dynamic contrast-enhanced MRI (DCE-MRI). Methods: Atherosclerotic plaques were induced in the aorta of 12 New Zealand White rabbits by a combination of endothelial denudation and high-cholesterol diet. Ten to sixteen weeks after surgery, DCE- MRI was performed with a fast spin echo T 1 weighted sequence. Thirty-five phases of images were obtained at 71-second intervals. Gd-DTPA was injected coincident with the third scan via marginal ear vein. Specimens were harvested within 12 hours after imaging for HE staining and CD31 immunohistochemical staining which was used to highlight neo-vessels. Plaque enhancement patterns were studied and compared with histological findings. Signal intensity of each plaque section was normalized to pre-contrast signal intensity of psoas muscle, after which signal intensity versus time curve was drawn. Pearson correlation coefficient was used to reveal association between histological neo-vessel count and descriptive parameters derived from signal intensity versus time curve. Results: Plaques were significantly enhanced by Gd-DTPA. Enhancement patterns could be described as 'fast-in and slow-out'. Differences in patterns of enhancement were observed between tissues, with fibrous tissue enhanced more than lipid aggregation and leukocyte foci. Peak enhancement (1.05±0.30), initial slope (0.82±0.28) and area under the curve at early phase (4.97± 1.67) derived from signal intensity-time curve had significant correlations with neo-vessel count (117.7± 93.3) (r=0.553, 0.468, 0.554 respectively, P<0.05). Conclusions: The enhanced patterns of atherosclerotic plaque by Gd-DTPA were 'fast- in and slow-out'. Neovascularization, increased endothelial permeability and extracellular matrix may be the reasons for

  2. Variability of ischiofemoral space dimensions with changes in hip flexion: an MRI study

    International Nuclear Information System (INIS)

    Johnson, Adam C.; Howe, Benjamin M.; Hollman, John H.; Finnoff, Jonathan T.

    2017-01-01

    The primary aim of this study was to determine if ischiofemoral space (IFS) dimensions vary with changes in hip flexion as a result of placing a bolster behind the knees during magnetic resonance imaging (MRI). A secondary aim was to determine if IFS dimensions vary between supine and prone hip neutral positions. The study employed a prospective design. Sports medicine center within a tertiary care institution. Five male and five female adult subjects (age mean = 29.2, range = 23-35; body mass index [BMI] mean = 23.5, range = 19.5-26.6) were recruited to participate in the study. An axial, T1-weighted MRI sequence of the pelvis was obtained of each subject in a supine position with their hips in neutral and flexed positions, and in a prone position with their hips in neutral position. Supine hip flexion was induced by placing a standard, 9-cm-diameter MRI knee bolster under the subject's knees. The order of image acquisition (supine hip neutral, supine hip flexed, prone hip neutral) was randomized. The IFS dimensions were then measured on a separate workstation. The investigator performing the IFS measurements was blinded to the subject position for each image. The main outcome measurements were the IFS dimensions acquired with MRI. The mean IFS dimensions in the prone position were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). In the supine hip neutral position, the IFS dimensions were 25.1 (SD 5.6) mm. The mean difference between the two positions of 3.15 (3.6) mm was statistically significant (95 % CI of the difference = 1.4 to 4.8 mm, t_1_9 = 3.911, p =.001). The mean IFS dimensions in the hip flexed position were 36.9 (SD 5.7) mm. The mean difference between the two supine positions of 11.8 (4.1) mm was statistically significant (95 % CI of the difference = 9.9 to 13.7 mm, t_1_9 = 12.716, p <.001). Our findings demonstrate that the IFS measurements obtained with MRI are dependent upon patient positioning with respect to hip flexion and supine versus

  3. Variability of ischiofemoral space dimensions with changes in hip flexion: an MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Adam C.; Howe, Benjamin M. [Mayo Clinic College of Medicine, Department of Radiology, Rochester, MN (United States); Hollman, John H.; Finnoff, Jonathan T. [Mayo Clinic College of Medicine, Department of Physical Medicine and Rehabilitation, Rochester, MN (United States)

    2017-01-15

    The primary aim of this study was to determine if ischiofemoral space (IFS) dimensions vary with changes in hip flexion as a result of placing a bolster behind the knees during magnetic resonance imaging (MRI). A secondary aim was to determine if IFS dimensions vary between supine and prone hip neutral positions. The study employed a prospective design. Sports medicine center within a tertiary care institution. Five male and five female adult subjects (age mean = 29.2, range = 23-35; body mass index [BMI] mean = 23.5, range = 19.5-26.6) were recruited to participate in the study. An axial, T1-weighted MRI sequence of the pelvis was obtained of each subject in a supine position with their hips in neutral and flexed positions, and in a prone position with their hips in neutral position. Supine hip flexion was induced by placing a standard, 9-cm-diameter MRI knee bolster under the subject's knees. The order of image acquisition (supine hip neutral, supine hip flexed, prone hip neutral) was randomized. The IFS dimensions were then measured on a separate workstation. The investigator performing the IFS measurements was blinded to the subject position for each image. The main outcome measurements were the IFS dimensions acquired with MRI. The mean IFS dimensions in the prone position were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). In the supine hip neutral position, the IFS dimensions were 25.1 (SD 5.6) mm. The mean difference between the two positions of 3.15 (3.6) mm was statistically significant (95 % CI of the difference = 1.4 to 4.8 mm, t{sub 19} = 3.911, p =.001). The mean IFS dimensions in the hip flexed position were 36.9 (SD 5.7) mm. The mean difference between the two supine positions of 11.8 (4.1) mm was statistically significant (95 % CI of the difference = 9.9 to 13.7 mm, t{sub 19} = 12.716, p <.001). Our findings demonstrate that the IFS measurements obtained with MRI are dependent upon patient positioning with respect to hip flexion and

  4. Quantitative Study of Longitudinal Relaxation (T 1) Contrast Mechanisms in Brain MRI

    Science.gov (United States)

    Jiang, Xu

    Longitudinal relaxation (T1) contrast in MRI is important for studying brain morphology and is widely used in clinical applications. Although MRI only detects signals from water hydrogen ( 1H) protons (WPs), T1 contrast is known to be influenced by other species of 1H protons, including those in macromolecules (MPs), such as lipids and proteins, through magnetization transfer (MT) between WPs and MPs. This complicates the use and quantification of T1 contrast for studying the underlying tissue composition and the physiology of the brain. MT contributes to T1 contrast to an extent that is generally dependent on MT kinetics, as well as the concentration and NMR spectral properties of MPs. However, the MP spectral properties and MT kinetics are both difficult to measure directly, as the signal from MPs is generally invisible to MRI. Therefore, to investigate MT kinetics and further quantify T1 contrast, we first developed a reliable way to indirectly measure the MP fraction and their exchange rate with WPs, with minimal dependence on the spectral properties of MPs. For this purpose, we used brief, highpower radiofrequency (RF) NMR excitation pulses to almost completely saturate the magnetization of MPs. Based on this, both MT kinetics and the contribution of MPs to T1 contrast through MT were studied. The thus obtained knowledge allowed us to subsequently infer the spectral properties of MPs by applying low-power, frequencyselective off-resonance RF pulses and measuring the offset-frequency dependent effect of MPs on the WP MRI signal. A two-pool exchange model was used in both cases to account for direct effects of the RF pulse on WP magnetization. Consistent with earlier works using MRI at low-field and post-mortem analysis of brain tissue, our novel measurement approach found that MPs constitute an up to 27% fraction of the total 1H protons in human brain white matter, and their spectrum follows a super-Lorentzian line with a T2 of 9.6+/-0.6 mus and a resonance

  5. MRI compatibility study of an integrated PET/RF-coil prototype system at 3 T

    Science.gov (United States)

    Akram, Md Shahadat Hossain; Obata, Takayuki; Suga, Mikio; Nishikido, Fumihiko; Yoshida, Eiji; Saito, Kazuyuki; Yamaya, Taiga

    2017-10-01

    We have been working on the development of a PET insert for existing magnetic resonance imaging (MRI) systems for simultaneous PET/MR imaging, which integrates radiofrequency (RF)-shielded PET detector modules with an RF head coil. In order to avoid interferences between the PET detector circuits and the different MRI-generated electromagnetic fields, PET detector circuits were installed inside eight Cu-shielded fiber-reinforced plastic boxes, and these eight shielded PET modules were integrated in between the eight elements of a 270-mm-diameter and 280-mm-axial-length cylindrical birdcage RF coil, which was designed to be used with a 3-T clinical MRI system. The diameter of the PET scintillators with a 12-mm axial field-of-view became 255 mm, which was very close to the imaging region. In this study, we have investigated the effects of this PET/RF-coil integrated system on the performance of MRI, which include the evaluation of static field (Bo) inhomogeneity, RF field (B1) distribution, local specific absorption rate (SAR) distribution, average SAR, and signal-to-noise ratio (SNR). For the central 170-mm-diameter and 80-mm-axial-length of a homogenous cylindrical phantom (with the total diameter of 200 mm and axial-length of 100 mm), an increase of about a maximum of 3 μT in the Bo inhomogeneity was found, both in the central and 40-mm off-centered transverse planes, and a 5 percentage point increase of B1 field inhomogeneity was observed in the central transverse plane (from 84% without PET to 79% with PET), while B1 homogeneity along the coronal plane was almost unchanged (77%) following the integration of PET with the RF head coil. The average SAR and maximum local SAR were increased by 1.21 and 1.62 times, respectively. However, the SNR study for both spin-echo and gradient-echo sequences showed a reduction of about 70% and 60%, respectively, because of the shielded PET modules. The overall results prove the feasibility of this integrated PET/RF-coil system

  6. The establishment of a multiple sclerosis model for clinical MRI study

    International Nuclear Information System (INIS)

    Zhang Haiqin; Li Kuncheng; Yu Chunshui; Ma Jia; Qin Wen; Ji Zhijuan; Piao Yueshan

    2009-01-01

    Objective: To establish a rat model of multiple sclerosis (MS) for clinical MRI study. Methods: The Lewis (LEW) rats were immunized by myelin oligodendrocyte glycoprotein peptide 35-55 (MOG 35-55 ) emulsified with complete Freunds adjuvant/incomplete Freunds adjuvant. Twenty LEW rats were selected. Group A rats were 5, group B rats were 10 and control group rats were 5. MRI and histopathology analysis were observed on group A and control group, and clinical course were observed on group B. The clinical course was observed and the brain and spinal cord of EAE rats were scanned on 3.0 T MR system with quadrature wrist joint coil on the third day of the acute stage of disease. The T 2 /T 1 weighted images and Gadolinium enhanced T 1 weighted images in 3D volume were obtained respectively. The magnetization transfer ratio (MTR) images were calculated with special software in workstation. Rats were sacrificed within 24 h after MRI, and the histopathological changes of central nervous system were observed. Results: Twice immunization of MOG 35-55 was used and a rat model of MS was successfully induced with all the rats. The model had varied clinical symptoms. The lesions of central nervous system at acute stage on group A (5 rats) were depicted on MRI. The lesions located in the brain and the spinal cord with main manifestation of hyperintensity on T 2 weighed images and hypointensity on T 1 weighted images. Some lesions had Gd-DTPA enhancement, and the value of MTR decreased. The infiltration of mononuclear cells around blood vessels and the extensive distribution of lesions of demyelination in brain and spinal cord were verified by histological examination. Conclusions: Twice immunization of MOG 35-55 could produce a rat model which mimics MS. The model is stable with higher incidence, and the antigen is cheap and obtained easily. The intravital monitoring of brain and spinal cord lesions in MOG 35-55 induced rat model is possible on 3.0 T clinical whole- body MR

  7. Simultaneous whole-body 18F-FDG PET-MRI in primary staging of breast cancer: A pilot study

    International Nuclear Information System (INIS)

    Taneja, Sangeeta; Jena, Amarnath; Goel, Reema; Sarin, Ramesh; Kaul, Sumaid

    2014-01-01

    Highlights: • Initial staging of breast cancer important in treatment planning and prognostication. • We assessed role of simultaneous 18 F-FDG PET-MRI in initial staging of breast cancer. • Primary, nodes and metastases on PET, MRI and PET-MRI for count and diagnostic confidence. • High diagnostic accuracy and confidence in detecting index and satellite lesions. • Comprehensive nodal and distant metastases staging with altered management (12 cases). - Abstract: Purpose: Accurate initial staging in breast carcinoma is important for treatment planning and for establishing the likely prognosis. The purpose of this study was to assess the utility of whole body simultaneous 18 F-FDG PET-MRI in initial staging of breast carcinoma. Methods: 36 patients with histologically confirmed invasive ductal carcinoma underwent simultaneous whole body 18 F-FDG PET-MRI on integrated 3 T PET-MR scanner (Siemens Biograph mMR) for primary staging. Primary lesion, nodes and metastases were evaluated on PET, MRI and PET-MRI for lesion count and diagnostic confidence (DC). Kappa co relation analysis was done to assess agreement between the satellite, nodal and metastatic lesions detected by PET and MRI. Histopathology, clinical/imaging follow-up served as the reference standard. Results: 36 patients with 37 histopathologically proven index breast cancer were retrospectively studied. Of 36 patients, 25 patients underwent surgery and 11 patients received systemic therapy. All index cancers were seen on PET and MR. Fused PET-MRI showed highest diagnostic confidence score of 5 as compared to PET (median 4; range 3–5) and MRI (median 4; range 4–5) alone. 2/36 (5.5%) patients were detected to have unsuspected contralateral synchronous cancer. 47 satellite lesions were detected on DCE MRI of which 23 were FDG avid with multifocality and multicentricity in 21 (58%) patients. Kappa co relation analysis revealed fair agreement for satellite lesion detection by the two modalities (κ

  8. Prevalence of abnormalities in knees detected by MRI in adults without knee osteoarthritis: population based observational study (Framingham Osteoarthritis Study).

    Science.gov (United States)

    Guermazi, Ali; Niu, Jingbo; Hayashi, Daichi; Roemer, Frank W; Englund, Martin; Neogi, Tuhina; Aliabadi, Piran; McLennan, Christine E; Felson, David T

    2012-08-29

    To examine use of magnetic resonance imaging (MRI) of knees with no radiographic evidence of osteoarthritis to determine the prevalence of structural lesions associated with osteoarthritis and their relation to age, sex, and obesity. Population based observational study. Community cohort in Framingham, MA, United States (Framingham osteoarthritis study). 710 people aged >50 who had no radiographic evidence of knee osteoarthritis (Kellgren-Lawrence grade 0) and who underwent MRI of the knee. Prevalence of MRI findings that are suggestive of knee osteoarthritis (osteophytes, cartilage damage, bone marrow lesions, subchondral cysts, meniscal lesions, synovitis, attrition, and ligamentous lesions) in all participants and after stratification by age, sex, body mass index (BMI), and the presence or absence of knee pain. Pain was assessed by three different questions and also by WOMAC questionnaire. Of the 710 participants, 393 (55%) were women, 660 (93%) were white, and 206 (29%) had knee pain in the past month. The mean age was 62.3 years and mean BMI was 27.9. Prevalence of "any abnormality" was 89% (631/710) overall. Osteophytes were the most common abnormality among all participants (74%, 524/710), followed by cartilage damage (69%, 492/710) and bone marrow lesions (52%, 371/710). The higher the age, the higher the prevalence of all types of abnormalities detectable by MRI. There were no significant differences in the prevalence of any of the features between BMI groups. The prevalence of at least one type of pathology ("any abnormality") was high in both painful (90-97%, depending on pain definition) and painless (86-88%) knees. MRI shows lesions in the tibiofemoral joint in most middle aged and elderly people in whom knee radiographs do not show any features of osteoarthritis, regardless of pain.

  9. Altered fractional amplitude of low frequency fluctuation in premenstrual syndrome: A resting state fMRI study.

    Science.gov (United States)

    Liao, Hai; Duan, Gaoxiong; Liu, Peng; Liu, Yanfei; Pang, Yong; Liu, Huimei; Tang, Lijun; Tao, Jien; Wen, Danhong; Li, Shasha; Liang, Lingyan; Deng, Demao

    2017-08-15

    Premenstrual syndrome (PMS) is becoming highly prevalent among female and is characterized by emotional, physical and behavior symptoms. Previous evidence suggested functional dysregulation of female brain was expected to be involved in the etiology of PMS. The aim of present study was to evaluate the alterations of spontaneous brain activity in PMS patients based on functional magnetic resonance imaging (fMRI). 20 PMS patients and 21 healthy controls underwent resting-state fMRI scanning during luteal phase. All participants were asked to complete a prospective daily record of severity of problems (DRSP) questionnaire. Compared with healthy controls, the results showed that PMS patients had increased fALFF in bilateral precuneus, left hippocampus and left inferior temporal cortex, and decreased fALFF in bilateral anterior cingulate cortex (ACC) and cerebellum at luteal phase. Moreover, the DRSP scores of PMS patients were negatively correlated with the mean fALFF in ACC and positively correlated with the fALFF in precuneus. (1) the study did not investigate whether or not abnormal brain activity differences between groups in mid-follicular phase, and within-group changes. between phases.(2) it was relatively limited sample size and the participants were young; (3) fALFF could not provide us with more holistic information of brain network;(4) the comparisons of PMS and premenstrual dysphoric disorder (PMDD) were not involved in the study. The present study shows abnormal spontaneous brain activity in PMS patients revealed by fALFF, which could provide neuroimaging evidence to further improve our understanding of the underlying neural mechanism of PMS. Copyright © 2017. Published by Elsevier B.V.

  10. “Awake” intraoperative functional MRI (ai-fMRI) for mapping the eloquent cortex: Is it possible in awake craniotomy?☆

    Science.gov (United States)

    Lu, Jun-Feng; Zhang, Han; Wu, Jin-Song; Yao, Cheng-Jun; Zhuang, Dong-Xiao; Qiu, Tian-Ming; Jia, Wen-Bin; Mao, Ying; Zhou, Liang-Fu

    2012-01-01

    As a promising noninvasive imaging technique, functional MRI (fMRI) has been extensively adopted as a functional localization procedure for surgical planning. However, the information provided by preoperative fMRI (pre-fMRI) is hampered by the brain deformation that is secondary to surgical procedures. Therefore, intraoperative fMRI (i-fMRI) becomes a potential alternative that can compensate for brain shifts by updating the functional localization information during craniotomy. However, previous i-fMRI studies required that patients be under general anesthesia, preventing the wider application of such a technique as the patients cannot perform tasks unless they are awake. In this study, we propose a new technique that combines awake surgery and i-fMRI, named “awake” i-fMRI (ai-fMRI). We introduced ai-fMRI to the real-time localization of sensorimotor areas during awake craniotomy in seven patients. The results showed that ai-fMRI could successfully detect activations in the bilateral primary sensorimotor areas and supplementary motor areas for all patients, indicating the feasibility of this technique in eloquent area localization. The reliability of ai-fMRI was further validated using intraoperative stimulation mapping (ISM) in two of the seven patients. Comparisons between the pre-fMRI-derived localization result and the ai-fMRI derived result showed that the former was subject to a heavy brain shift and led to incorrect localization, while the latter solved that problem. Additionally, the approaches for the acquisition and processing of the ai-fMRI data were fully illustrated and described. Some practical issues on employing ai-fMRI in awake craniotomy were systemically discussed, and guidelines were provided. PMID:24179766

  11. Hearing loss associated with repeated MRI acquisition procedure-related acoustic noise exposure: an occupational cohort study.

    Science.gov (United States)

    Bongers, Suzan; Slottje, Pauline; Kromhout, Hans

    2017-11-01

    To study the effects of repeated exposure to MRI-related acoustic noise during image acquisition procedures (scans) on hearing. A retrospective occupational cohort study was performed among workers of an MRI manufacturing facility (n=474). Longitudinal audiometry data from the facility's medical surveillance scheme collected from 1973 to 2010 were analysed by studying the association of cumulative exposure to MRI-related acoustic noise from voluntary (multiple) MRI scans and the hearing threshold of the volunteer. Repeated acoustic noise exposure during volunteer MRI scans was found to be associated with a small exposure-dependent increased rate change of hearing threshold level (dB/year), but the association was only found related to the number of voluntary MRI scans and not to modelled cumulative noise exposure (dB*hour) based on MRI-system type. The increased rate change of hearing threshold level was found to be statistically significant for the frequencies 500, 1000, 2000, 3000 and 4000 Hz in the right ear. From our longitudinal cohort study, it appeared that exposure to noise from voluntarily MRI scans may have resulted in a slight amount of hearing loss. Mandatory use of hearing protection might have prevented more severe hearing loss. Lack of consistency in findings between the left and right ears and between the two exposure measures prohibits definitive conclusions. Further research that addresses the study's methodological limitations is warranted to corroborate our findings. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  12. Neural correlates of social motivation: an fMRI study on power versus affiliation.

    Science.gov (United States)

    Quirin, Markus; Meyer, Frank; Heise, Nils; Kuhl, Julius; Küstermann, Ekkehard; Strüber, Daniel; Cacioppo, John T

    2013-06-01

    Power versus affiliation motivations refer to two different strivings relevant in the context of social relationships. We used functional magnetic resonance imaging (fMRI) to determine neural structures involved in power versus affiliation motivation based on an individual differences approach. Seventeen participants provided self-reports of power and affiliation motives and were presented with love, power-related, and control movie clips. The power motive predicted activity in four clusters within the left prefrontal cortex (PFC), while participants viewed power-related film clips. The affiliation motive predicted activity in the right putamen/pallidum while participants viewed love stories. The present findings extend previous research on social motivations to the level of neural functioning and suggest differential networks for power-related versus affiliation-related social motivations. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition

    Science.gov (United States)

    Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John

    2013-01-01

    BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition. PMID:24961428

  14. Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition

    Directory of Open Access Journals (Sweden)

    John Wright

    2013-05-01

    Full Text Available BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1 already proficient in at least two languages; or (2 are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1 longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2 statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition.

  15. Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition.

    Science.gov (United States)

    Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John

    2013-05-28

    BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition.

  16. A study on clinical findings about vertebral disease diagnosed with MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ham-Gyum [Ansan College, Seoul (Korea, Republic of)

    2006-09-15

    In order to analyze clinical characteristics like sex-and age-based onset frequency and onset region from vertebral disease cases, this study investigated total 1,291 cases of vertebral disease that were diagnosed via magnetic resonance imaging (MRI) from January to December 2004 at B University Hospital in metropolitan area. For higher diagnostic accuracy in cases of spinal disorder diagnosed, this study analyzed findings from data reading conducted by veteran specialists in diagnostic radiology. But this study excluded uncertain lesion cases, the cases requiring differential diagnosis from other disorders and so on from subjects under analysis. This study employed superconductive 1.5 Tesla SIGNA MR/i for MRI test and basically received resulting images via FSE (fast spin echo). In particular, this study obtained T1 and T2 myelogram with regard to regional characteristics (such as cervical vertebrae, thoracic vertebrae and lumbar vertebra) and imaging characteristics for sagittal and transverse section. As a result, this study came to the following conclusions: 1. In terms of general characteristics of subjects under analysis, male group comprised 53.5% and female 46.5% out of total 1,291 subjects. 2. The regional onset frequency of spinal disorders was converged primarily on lumbar vertebra (65.5%), which was followed by cervical vertebrae (27.3%) and thoracic vertebrae (7.0%) respectively. 3. Top 10 cases with high onset frequency of spinal disorders can be listed as follows: 1) posterior bulging disc 65.8% 2) narrowing of neural foramen 23.8% 3) herniated intervertebral disc (HIVD) 22.4% 4) spinal stenosis 16.7% 5) osteochondrosis 6.4% 6) compression fracture 6.4% 7) facet joint arthropathy 6.2% 8) spondylolisthesis 6.0% 9) spinal cord tumor 3.5% 10) inter body fusion 2.6%.

  17. A study on clinical findings about vertebral disease diagnosed with MRI

    International Nuclear Information System (INIS)

    Kim, Ham-Gyum

    2006-01-01

    In order to analyze clinical characteristics like sex-and age-based onset frequency and onset region from vertebral disease cases, this study investigated total 1,291 cases of vertebral disease that were diagnosed via magnetic resonance imaging (MRI) from January to December 2004 at B University Hospital in metropolitan area. For higher diagnostic accuracy in cases of spinal disorder diagnosed, this study analyzed findings from data reading conducted by veteran specialists in diagnostic radiology. But this study excluded uncertain lesion cases, the cases requiring differential diagnosis from other disorders and so on from subjects under analysis. This study employed superconductive 1.5 Tesla SIGNA MR/i for MRI test and basically received resulting images via FSE (fast spin echo). In particular, this study obtained T1 and T2 myelogram with regard to regional characteristics (such as cervical vertebrae, thoracic vertebrae and lumbar vertebra) and imaging characteristics for sagittal and transverse section. As a result, this study came to the following conclusions: 1. In terms of general characteristics of subjects under analysis, male group comprised 53.5% and female 46.5% out of total 1,291 subjects. 2. The regional onset frequency of spinal disorders was converged primarily on lumbar vertebra (65.5%), which was followed by cervical vertebrae (27.3%) and thoracic vertebrae (7.0%) respectively. 3. Top 10 cases with high onset frequency of spinal disorders can be listed as follows: 1) posterior bulging disc 65.8% 2) narrowing of neural foramen 23.8% 3) herniated intervertebral disc (HIVD) 22.4% 4) spinal stenosis 16.7% 5) osteochondrosis 6.4% 6) compression fracture 6.4% 7) facet joint arthropathy 6.2% 8) spondylolisthesis 6.0% 9) spinal cord tumor 3.5% 10) inter body fusion 2.6%

  18. SU-E-J-222: Feasibility Study of MRI-Only Proton Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Spadea, M [ImagEngLab, Magna Graecia University, Catanzaro (Italy); Izquierdo, D; Catana, C [Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA (United States); Collins-Fekete, C; Bortfeld, T; Seco, J [Massachusetts General Hospital, Harvard Medical, Boston, MA (United States)

    2015-06-15

    Purpose: To assess the dosimetric equivalence of MRI based proton planning vs. single energy x-ray CT. Methods: 8 glioblastoma patients were imaged with CT and MRI after surgical resection. T1-weighted 3DMPRAGE was used to delineate the GTV, which was subsequently rigidly registered to the CT volume. A pseudoCT was generated from the aligned MRI by combining segmentation and atlas-based approaches. The spatial resolution both for pseudo- and real CT was 0.6×0.6×2.5mm. Three orthogonal proton beams were simulated on the pseudoCT. Two co-planar beams were set on the axial plane. The third one was planned parallel to the cranio-caudal (CC) direction. Each beam was set to cover the GTV at 98% of the nominal dose (18Gy). The proton plan was copied and transferred to the real CT, including aperture/compensator geometry. Dose comparison between pseudoCT and CT plan was performed beam-by-beam by quantifying the range shift of dose profile on each slice of the GTV. The GTV’s V{sub 98} was computed for the CT. Results: For beams in axial plane the median absolute value of the range shift was 0.3mm, with 0.9mm and 1.4mm as 95th percentile and maximum, respectively. Worst scenarios were found for the CC beam, where we measured 1.1mm (median), 2.7mm (95thpercentile) and 5mm (maximum). Regardless the direction, beams passing through the surgical site, where metal (Titanium MRI-compatible) staples were present, were mostly affected by range shift. GTV’s V{sub 98} for CT was not lower than 99.3%. Conclusion: The study showed the clinical feasibility of an MRI-alone proton plan. Advantages include the possibility to rely on better soft tissue contrast for target and organs at risk delineation without the need of further CT scan and image registration. Additional investigation is required in presence of metal implants along the beam path and to account for partial volume effects due to slice thickness.

  19. SU-E-J-222: Feasibility Study of MRI-Only Proton Therapy Planning

    International Nuclear Information System (INIS)

    Spadea, M; Izquierdo, D; Catana, C; Collins-Fekete, C; Bortfeld, T; Seco, J

    2015-01-01

    Purpose: To assess the dosimetric equivalence of MRI based proton planning vs. single energy x-ray CT. Methods: 8 glioblastoma patients were imaged with CT and MRI after surgical resection. T1-weighted 3DMPRAGE was used to delineate the GTV, which was subsequently rigidly registered to the CT volume. A pseudoCT was generated from the aligned MRI by combining segmentation and atlas-based approaches. The spatial resolution both for pseudo- and real CT was 0.6×0.6×2.5mm. Three orthogonal proton beams were simulated on the pseudoCT. Two co-planar beams were set on the axial plane. The third one was planned parallel to the cranio-caudal (CC) direction. Each beam was set to cover the GTV at 98% of the nominal dose (18Gy). The proton plan was copied and transferred to the real CT, including aperture/compensator geometry. Dose comparison between pseudoCT and CT plan was performed beam-by-beam by quantifying the range shift of dose profile on each slice of the GTV. The GTV’s V 98 was computed for the CT. Results: For beams in axial plane the median absolute value of the range shift was 0.3mm, with 0.9mm and 1.4mm as 95th percentile and maximum, respectively. Worst scenarios were found for the CC beam, where we measured 1.1mm (median), 2.7mm (95thpercentile) and 5mm (maximum). Regardless the direction, beams passing through the surgical site, where metal (Titanium MRI-compatible) staples were present, were mostly affected by range shift. GTV’s V 98 for CT was not lower than 99.3%. Conclusion: The study showed the clinical feasibility of an MRI-alone proton plan. Advantages include the possibility to rely on better soft tissue contrast for target and organs at risk delineation without the need of further CT scan and image registration. Additional investigation is required in presence of metal implants along the beam path and to account for partial volume effects due to slice thickness

  20. Is external rotation the correct immobilisation for acute shoulder dislocation? An MRI study.

    Science.gov (United States)

    Siegler, J; Proust, J; Marcheix, P S M; Charissoux, J L; Mabit, C; Arnaud, J P

    2010-06-01

    Anterior dislocation of the shoulder is frequent, with high rates of recurrence. Immobilization in external rotation (ER) seems to improve results, although few studies have actually demonstrated this. The present MRI study examined the impact of ER on labral and capsular ligamentous complex lesions after primary dislocation. A prospective study was started up on January 1st, 2007. Inclusion criteria were: acute initial anteromedial dislocation of the shoulder, without past history of shoulder trauma. There were 23 such patients, with a mean age of 37 years. Early MRI scan used the following protocol: one acquisition in internal rotation followed by one in ER. Study criteria were: hemarthrosis, ER amplitude, rotator cuff status, bone lesion, and labral lesion stage (Habermeyer's classification) and displacement (Itoi criteria). There were 12 right and 11 left shoulders. Mean time to MRI was 3.7 days. There were three rotator cuff tears, no glenal lesions, and 14 humeral notches. Hemarthrosis was almost systematically present, with its distribution modified by ER in 75% of cases; three patients showed no posterior hemarthrosis, in whatever rotation. Mean ER was 37 degrees. On Habermeyer's classification, there were 12 stage-1 lesions, and 10 stage-2; one patient had no labral lesion. All separated labra were reduced in ER, five (21%) totally. In six cases, labral displacement changed according to rotation. All ant