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Sample records for mri comparative study

  1. 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...

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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.)

  7. 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

  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. 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)

  10. 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)

  11. 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.)

  12. 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.)

  13. 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

  14. 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

  15. Comparative study between MRI and echocardiography in noncompaction of ventricular myocardium

    International Nuclear Information System (INIS)

    Sun Ziyan; Xia Liming; Wang Chengyuan; Rao Jingjing; Shenyu Weihui

    2007-01-01

    Objective: To investigate the MRI and echocardiography manifestations of noncompaction of ventricular myocardium(NVM) and assess the role of MR1 in the diagnosis of NVM by comparing it with echocardiography. Methods: Fourteen cases of NVM diagnosed by echocardiography were examined with MRI, including scanning of black-blood sequences, double inversion recovery fast spin echo (DIBFSE) and triple inversion recovery fast spin echo (TIRFSE), and white blood sequence: fast imaging employ steady state acquisition (FIESTA). Scanning plane includes short axis view, four-chamber view and long axis view. Results: Both MRI and echocardiography displayed involvement of left ventricles in thirteen cases and involvement of double ventricles in one case. Apexes of heart and the intermedius are commonly affected. MRI showed 54 segments and echocardiography showed 53 segments affected, and there is no significant difference between the capability of MRI and echocardiography (P=1,000). The affected myocardium consisted of two layers: subendocardial noncompacted myocardium and epicardial compacted myocardium, and the ratio measurement of N/C by MRI was 3.37±0.89 and it was 3.19±0.82 by echocardiography. Noncompacted myocardium was characterized by prominent and excessive myocardial trabeculations and deep intratrabecular recesses, in which the blood flow was communicated with the ventricle. One case was complicated with ventricular aneurysm, and coronary arteriography was performed with unremarkable findings. One case underwent heart transplantation because of progressive heart failure, Gross findings demonstrated prominent muscular' trabeculations with deep intratrabecular recesses, which coincided well with MRI findings. Conclusion: The MRI manifestation of NVM is characteristic, and MRI with multiple series and planes is helpful in the diagnose of NVM. Compared with echocardiography, MRI could display the pathological cardiac muscle more clearly, because of its high soft

  16. A comparative study of symptoms in multiple lacunar state and MRI findings

    International Nuclear Information System (INIS)

    Shibata, Youichi

    1993-01-01

    A multiple lacunar state is considered to cause gait disturbance, pseudobulbar palsy, or silent stroke. In the present study, these symptoms is multiple lacunar state and the incidences of abnormal findings on magnetic resonance imaging (MRI) were investigated comparatively. Thirty-eight patients (23 males and 15 females; average age 73.6 y.o.) with ischemic cerebral lesions on T 2 weighted images of MRI were studied. In the group with gait disturbance only, the incidences of widening of the ventricular system and periventricular hyperintensity (PVH) around the frontal horn were significantly high compared with the group with silent stroke (p<0.01, p<0.005; respectively), and hyperintensity area of the semioval center were demonstrated prominently in the regions perfused by anterior cerebral artery. In the group with pseudobulbar palsy only, the incidences of PVH around the posterior part of the lateral ventricle and hyperintensity area of the basal ganglion region were significantly high as compared with the group with silent stroke (p<0.01, p<0.05; respectively), and hyperintensity area of the semioval center were demonstrated prominently in the regions perfused by middle cerebral artery. (author)

  17. A comparative study of symptoms in multiple lacunar state and MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Youichi (Saint Marianna Univ., Kawasaki (Japan). School of Medicine)

    1993-10-01

    A multiple lacunar state is considered to cause gait disturbance, pseudobulbar palsy, or silent stroke. In the present study, these symptoms is multiple lacunar state and the incidences of abnormal findings on magnetic resonance imaging (MRI) were investigated comparatively. Thirty-eight patients (23 males and 15 females; average age 73.6 y.o.) with ischemic cerebral lesions on T[sub 2] weighted images of MRI were studied. In the group with gait disturbance only, the incidences of widening of the ventricular system and periventricular hyperintensity (PVH) around the frontal horn were significantly high compared with the group with silent stroke (p<0.01, p<0.005; respectively), and hyperintensity area of the semioval center were demonstrated prominently in the regions perfused by anterior cerebral artery. In the group with pseudobulbar palsy only, the incidences of PVH around the posterior part of the lateral ventricle and hyperintensity area of the basal ganglion region were significantly high as compared with the group with silent stroke (p<0.01, p<0.05; respectively), and hyperintensity area of the semioval center were demonstrated prominently in the regions perfused by middle cerebral artery. (author).

  18. MRI features of three paediatric intra-articular synovial lesions: a comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Kan, J.H. [Monroe Carell Jr. Children' s Hospital at Vanderbilt, Nashville, TN (United States)], E-mail: herman.kan@vanderbilt.edu; Hernanz-Schulman, M. [Monroe Carell Jr. Children' s Hospital at Vanderbilt, Nashville, TN (United States); Damon, B.M.; Yu, Chang [Vanderbilt University, Nashville, TN (United States); Connolly, S.A. [Boston Children' s Hospital, Boston, IL (United States)

    2008-07-15

    Aim: To determine reliable magnetic resonance imaging (MRI) features differentiating three paediatric intra-articular congenital or neoplastic synovial lesions that contain blood products, from post-traumatic or haemorrhagic inflammatory processes. Materials and methods: This was a retrospective review of MRI findings of 22 paediatric intra-articular congenital or neoplastic synovial lesions, including venous malformation (VM) (n = 12), pigmented villonodular synovitis (PVNS; n = 8), and synovial sarcoma (SS; n = 2). These MRI features were compared with 22 paediatric post-traumatic or inflammatory intra-articular processes containing blood products and producing mass effect. The following imaging features were assessed: presence of a discrete mass, extension, extra-articular oedema, susceptibility, joint effusion, and size. Fisher's exact test was used and results were considered statistically significant when p < 0.05. Results: The three intra-articular synovial lesions, compared with controls, were more likely to directly invade osseous structures when a discrete mass was present (13/16, 81.3% versus 1/9, 11.1%; p < 0.002) and extend into extra-articular soft tissues (13/21, 61.9% versus 2/17, 11.8%; p < 0.003), but were less likely to show extra-articular oedema (3/22, 13.6% versus 13/22, 59.1%; p < 0.004), a joint effusion (10/22,45.5% versus 19/22, 86.4%, p < 0.01), susceptibility within a joint effusion (0/22, 0% versus 11/22, 40.9%; p = 0.00), osseous oedema (3/16, 18.8% versus 7/9, 77.8%; p < 0.009), and synovial enhancement (8/21, 38.1% versus 14/16, 87.5%; p < 0.003). VMs had characteristic tubular vessels with internal fluid-fluid levels (11/12) that extended into bone (10/12) and extracapsular soft tissues (11/12). Conclusion: Our study indicates that, despite the overlapping presence of haemorrhagic products, intra-articular VM, PVNS, and SS show MRI features that permit distinction from acquired post-traumatic and haemorrhagic inflammatory

  19. The cranial MRI in severe cerebral palsy; A comparative study with clinical data

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Kazutaka; Itoh, Masahiro; Fueki, Noboru; Hirasawa, Kyoko; Suzuki, Noriko; Kurata, Kiyoko (Metropolitan Medical Center of the Severely Handicapped, Tokyo (Japan)); Sato, Junichi; Morimatsu, Yoshio; Yagishita, Akira

    1993-09-01

    The magnetic resonance examination was performed in 38 patients with severe cerebral palsy (CP; 15 males and 23 females) who had both motor delay (unable to move anywhere) and mental retardation (I.Q. or D.Q. below 30). Neuroimaging findings were compared with the CP type, etiology, and grade of understanding of language. Cranial magnetic resonance imagings (MRI) in CP were divided into five types. In type 1, nine predominantly showed cyst-liked ventricles and periventricular hyperintensity on T[sub 2]-weighted imaging (PVH) and only scarred basal ganglia and thalamus were visible. All suffered from neonatal asphyxia and the clinical type was rigospastic tetraplegia (RST). In type 2, eleven predominantly showed PVH and hyperintensity on T[sub 2]-weighted (HT2) in basal ganglia and thalamus. All suffered from neonatal asphyxia and the clinical type was RST or rigospastic diplegia. In type 3, five showed PVH and three had cortical atrophy. All suffered from neonatal asphyxia and the clinical type was spastic diplegia. In type 4, four predominantly showed HT2 in putamen and thalamus. Three had cortical atrophy. All suffered from neonatal asphyxia. The clinical type was athetotic CP (ATH). In type 5, nine predominantly showed HT2 in globus pallidus. Four had cortical atrophy and two had hippocampal atrophy. All suffered from neonatal jaundice and the clinical type was ATH. All patients who suffered from neonatal asphyxia and spastic CP had MRI in PVH. All patients who suffered from neonatal asphyxia and ATH showed HT2 in putamen and thalamus. Almost patients who suffered from neonatal jaundice and ATH showed HT2 in globus pallidus. With athetotic CP, cases with atrophy of the cerebral cortex and/or hippocampus were lower grade of understanding of language than no atrophy of both. The results of studies of MRI are in agreement with neuropathological findings. (author).

  20. Processing of vocalizations in humans and monkeys: A comparative fMRI study

    International Nuclear Information System (INIS)

    Joly, Olivier; Orban, Guy A.; Pallier, Christophe; Ramus, Franck; Pressnitzer, Daniel; Vanduffel, Wim

    2012-01-01

    Humans and many other animals use acoustical signals to mediate social interactions with con-specifics. The evolution of sound-based communication is still poorly understood and its neural correlates have only recently begun to be investigated. In the present study, we applied functional MRI to humans and macaque monkeys listening to identical stimuli in order to compare the cortical networks involved in the processing of vocalizations. At the first stages of auditory processing, both species showed similar fMRI activity maps within and around the lateral sulcus (the Sylvian fissure in humans). Monkeys showed remarkably similar responses to monkey calls and to human vocal sounds (speech or otherwise), mainly in the lateral sulcus and the adjacent superior temporal gyrus (STG). In contrast, a preference for human vocalizations and especially for speech was observed in the human STG and superior temporal sulcus (STS). The STS and Broca's region were especially responsive to intelligible utterances. The evolution of the language faculty in humans appears to have recruited most of the STS. It may be that in monkeys, a much simpler repertoire of vocalizations requires less involvement of this temporal territory. (authors)

  1. MRI findings of pancreatic lymphoma and autoimmune pancreatitis: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Ishigami, Kousei, E-mail: Ishigamikousei@aol.co [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582 (Japan); Tajima, Tsuyoshi; Nishie, Akihiro; Ushijima, Yasuhiro [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582 (Japan); Fujita, Nobuhiro [Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University (Japan); Asayama, Yoshiki; Kakihara, Daisuke; Irie, Hiroyuki [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582 (Japan); Ito, Tetsuhide; Igarashi, Hisato [Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University (Japan); Nakamura, Masafumi [Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University (Japan); Honda, Hiroshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582 (Japan)

    2010-06-15

    Purpose: To clarify whether there are differences in MRI findings between pancreatic lymphomas and autoimmune pancreatitis (AIP). Materials and methods: MRI of 8 patients with pancreatic lymphomas and 21 patients with AIP were retrospectively reviewed. For multifocal pancreatic lymphomas (n = 2) and AIP (n = 4), the largest 2 lesions were evaluated. Ten pancreatic lymphomas and 25 AIP were compared on three bases: the signal intensity on T2-weighted images, internal homogeneity, and presence or absence of capsule-like rim. In 8 lymphomas and 19 AIP, the enhancement pattern on dynamic MRI was compared, as well. Results: On T2-weighted images, pancreatic lymphomas comprised 5, 5 and 4 lesions with low (iso), slightly high, and moderately high intensity, respectively, while the numbers for AIP were 14, 10, and 1 (P < 0.01). Nine of 10 (90%) lymphomas appeared homogenous, and 11 of 25 (44%) AIP were homogenous (P < 0.05). A capsule-like rim was present in 9 of 25 (36%) AIP, but was not seen in lymphomas (P < 0.05). On dynamic MRI, 18 of 19 (94.7%) AIP showed persistent (n = 5) or delayed enhancement (n = 13), and 6 of 8 (75%) lymphomas showed low intensity without delayed enhancement (P < 0.001). Conclusion: MRI findings for pancreatic lymphomas and AIP were significantly different, which may be helpful for the differential diagnosis of these two diseases.

  2. Longitudinal study comparing sonographic and MRI assessments of acute and healing hamstring injuries

    NARCIS (Netherlands)

    Connell, David A.; Schneider-Kolsky, Michal E.; Hoving, Jan Lucas; Malara, Frank; Buchbinder, Rachelle; Koulouris, George; Burke, Frank; Bass, Cheryl

    2004-01-01

    OBJECTIVE: We compared sonography and MRI for assessing hamstring injuries in professional football players (Australian football) 3 days, 2 weeks, and 6 weeks after an injury and identified imaging characteristics at baseline that may be useful in predicting the time needed for return to

  3. 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.)

  4. 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.)

  5. A Comparative Study of Pituitary Volume Variations in MRI in Acute Onset of Psychiatric Conditions.

    Science.gov (United States)

    Soni, Brijesh Kumar; Joish, Upendra Kumar; Sahni, Hirdesh; George, Raju A; Sivasankar, Rajeev; Aggarwal, Rohit

    2017-02-01

    The growing belief that endocrine abnormalities may underlie many mental conditions has led to increased use of imaging and hormonal assays in patients attending to psychiatric OPDs. People who are in an acute phase of a psychiatric disorder show Hypothalamic Pituitary Adrenal (HPA) axis hyperactivity, but the precise underlying central mechanisms are unclear. To assess the pituitary gland volume variations in patients presenting with new onset acute psychiatric illness in comparison with age and gender matched controls by using MRI. The study included 50 patients, with symptoms of acute psychiatric illness presenting within one month of onset of illness and 50 age and gender matched healthy controls. Both patients and controls were made to undergo MRI of the Brain. A 0.9 mm slices of entire brain were obtained by 3 dimensional T1 weighted sequence. Pituitary gland was traced in all sagittal slices. Anterior pituitary and posterior pituitary bright spot were measured separately in each slice. Volume of the pituitary (in cubic centimetre- cm 3 ) was calculated by summing areas. Significance of variations in pituitary gland volumes was compared between the cases and controls using Analysis of Covariance (ANOVA). There were significantly larger pituitary gland volumes in the cases than the controls, irrespective of psychiatric diagnosis (ANOVA, f=15.56; p=0.0002). Pituitary volumes in cases were 15.36% (0.73 cm 3 ) higher than in controls. There is a strong likelihood of HPA axis overactivity during initial phase of all mental disorders along with increased pituitary gland volumes. Further studies including hormonal assays and correlation with imaging are likely to provide further insight into neuroanatomical and pathological basis of psychiatric disorders.

  6. Facial Expression Enhances Emotion Perception Compared to Vocal Prosody: Behavioral and fMRI Studies.

    Science.gov (United States)

    Zhang, Heming; Chen, Xuhai; Chen, Shengdong; Li, Yansong; Chen, Changming; Long, Quanshan; Yuan, Jiajin

    2018-05-09

    Facial and vocal expressions are essential modalities mediating the perception of emotion and social communication. Nonetheless, currently little is known about how emotion perception and its neural substrates differ across facial expression and vocal prosody. To clarify this issue, functional MRI scans were acquired in Study 1, in which participants were asked to discriminate the valence of emotional expression (angry, happy or neutral) from facial, vocal, or bimodal stimuli. In Study 2, we used an affective priming task (unimodal materials as primers and bimodal materials as target) and participants were asked to rate the intensity, valence, and arousal of the targets. Study 1 showed higher accuracy and shorter response latencies in the facial than in the vocal modality for a happy expression. Whole-brain analysis showed enhanced activation during facial compared to vocal emotions in the inferior temporal-occipital regions. Region of interest analysis showed a higher percentage signal change for facial than for vocal anger in the superior temporal sulcus. Study 2 showed that facial relative to vocal priming of anger had a greater influence on perceived emotion for bimodal targets, irrespective of the target valence. These findings suggest that facial expression is associated with enhanced emotion perception compared to equivalent vocal prosodies.

  7. The comparative study of lumbar disc disruption with MRI and CT discography

    International Nuclear Information System (INIS)

    Chen Xingcan; Liu Naifang; Li Xiaohong; Xu Wengen; Zou Qing; Yang Yonghong

    2005-01-01

    Objective: To compare MRI with CT discography (CTD) for diagnostic assessment of lumbar disc disruption. Methods: Paired comparative examination in 16 patients with chronic lower back pain without radicular pain and no disc herniation was conducted using CT or MRI. The standard of CTD classification and positive disc was formulated and the correlation between the induced lower back pain and dosage used in CTD was observed. Results: For a total of 21 discs in the 16 patients, CTD showed the disc as type 2 in 12 discs and type 5 in 1 disc with 13 positive discs, while MRI only showed the high-intensity zone of posterior annulus in 6 discs as the indirect sign of disc disruption and disc degeneration in 7 discs. Conclusion: CTD was the only method for showing the direct sign of disc disruption. The induced lower back pain was related with the type of disc disruption. MRI can show some of the indirect signs of disc disruption and CTD can show the direct sign of disc disruption. (authors)

  8. Comparative study of radiography, CT and MRI in the identification of hip involvement in patients with ankylosing spondylitis

    International Nuclear Information System (INIS)

    Huang Zhenguo; Zhang Xuezhe; Hu Libin; Wang Guochun; Zhou Huiqiong; Lu Xin; Wang Wu

    2012-01-01

    Objective: To study the imaging findings of hip involvement and to compare the sensitivity of radiography, CT, and MRI in the identification of hip involvement in patients with ankylosing spondylitis (AS). Methods: Anteroposterior radiography of the pelvis and MRI of hip were performed in 55 patients with AS. CT scan of hip was performed in 29 of 55 patients. T 1 -weighted, T 2 -weighted, short tau inversion recovery (STIR) and three dimensional balanced turbo field echo with water selective excitation (3D-BTFE-WATS) coronal sequences of hips were obtained in all patients, of which fat-saturated contrast-enhanced T 1 -weighted sequence was performed in 24 patients. The imaging data of 55 patients were analyzed. The chi-square test was used to analyze the sensitivity in the identification of hip involvement among radiography, CT, and MRI. Results: Among 110 hips in all 55 patients, abnormal changes were detected in 13 hips by radiography, 85 hips by MRI. The findings of radiography included bone erosions in 13 hips, joint space narrowing in 4 hips,syndesmophytes in 5 hips. MRI revealed bone erosive destruction in 31 hips, joint space narrowing in 4 hips, joint effusion in 80 hips, subchondral bone marrow edema in 32 hips, fat accumulation of bone marrow in 28 hips, enthesitis in 21 hips. Bilateral synovial enhancement was showed in 19 of 24 patients who underwent fat-saturated contrast-enhanced T 1 -weighted sequence. Of the 58 hip joints in 29 patients who underwent CT examination, not only did CT show all bone erosions detected by radiography and MRI, but CT revealed bone erosive destruction that were not identified by radiography in 10 hips and by MRI in 1 hip as well. Abnormal changes were detected in 10.3% (6/58)by radiography, 27.6% (16/58) by CT, and 77.6% (45/58) by MRI. The sensitivity of MRI in the identification of hip involvement is higher than that of radiography and CT (χ 2 =53.22 and 29.08, P<0.05). In addition to chronic bone structural changes, MRI

  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. A comparative study of radionuclide bone scan, X-ray and MRI on early femoral head necrosis in adults

    International Nuclear Information System (INIS)

    Liu Jihua; Ji Qinglian; Xu Aide; Zuo Shuyao; Gao Zhenhua

    2004-01-01

    Objective: To summarize radionuclide bone scan signs in the early femoral head necrosis (FHN) in adults, to compare them with MRI and X-ray findings and to discuss the pathological basis of radionuclide bone scan findings from the view of MRI. Methods: Forty cases (63 hips) with early FHN in adult patients proved by follow-up studies or pathology were analyzed. All patients underwent radionuclide bone scan, MRI and X-ray examination within a period of less than 7 d separately. Results: 1) Radionuclide bone scan manifestations of the early FHN corresponding to different MRI signs included: focally decreased uptake of radioisotope, focally increased uptake, atypical or typical doughnut sign, mildly increased uptake in the superior part of femoral head with band-like region of obviously increased uptake in inferior part of femoral head or femoral neck, and diffused increase of uptake in the whole head. 2) In 40 cases (63 hips), there was statistical difference in diagnosis early FHN in adults not only between radionuclide bone scan and X-ray but also between MRI and X-ray in sensitivity (P 0.05). Conclusions: 1) The atypical or typical doughnut sign and mildly increased uptake in the superior part of femoral head with band-like region of obviously increased uptake in inferior part of femoral head or neck are specific signs for diagnosing early FHN. 2) For sensitivity, radionuclide bone scan and MRI are equally superior to X-ray. (authors)

  11. Classification of fMRI resting-state maps using machine learning techniques: A comparative study

    Science.gov (United States)

    Gallos, Ioannis; Siettos, Constantinos

    2017-11-01

    We compare the efficiency of Principal Component Analysis (PCA) and nonlinear learning manifold algorithms (ISOMAP and Diffusion maps) for classifying brain maps between groups of schizophrenia patients and healthy from fMRI scans during a resting-state experiment. After a standard pre-processing pipeline, we applied spatial Independent component analysis (ICA) to reduce (a) noise and (b) spatial-temporal dimensionality of fMRI maps. On the cross-correlation matrix of the ICA components, we applied PCA, ISOMAP and Diffusion Maps to find an embedded low-dimensional space. Finally, support-vector-machines (SVM) and k-NN algorithms were used to evaluate the performance of the algorithms in classifying between the two groups.

  12. MRI, PET/CT and ultrasound in the preoperative staging of endometrial cancer - A multicenter prospective comparative study

    DEFF Research Database (Denmark)

    Antonsen, Sofie Leisby; Jensen, Lisa Neerup; Loft, Annika

    2012-01-01

    OBJECTIVES: The aim of this prospective multicenter study was to evaluate and compare the diagnostic performance of PET/CT, MRI and transvaginal two-dimensional ultrasound (2DUS) in the preoperative assessment of endometrial cancer (EC). METHODS: 318 consecutive women with EC were included when...

  13. Tumour auto-contouring on 2d cine MRI for locally advanced lung cancer: A comparative study.

    Science.gov (United States)

    Fast, Martin F; Eiben, Björn; Menten, Martin J; Wetscherek, Andreas; Hawkes, David J; McClelland, Jamie R; Oelfke, Uwe

    2017-12-01

    Radiotherapy guidance based on magnetic resonance imaging (MRI) is currently becoming a clinical reality. Fast 2d cine MRI sequences are expected to increase the precision of radiation delivery by facilitating tumour delineation during treatment. This study compares four auto-contouring algorithms for the task of delineating the primary tumour in six locally advanced (LA) lung cancer patients. Twenty-two cine MRI sequences were acquired using either a balanced steady-state free precession or a spoiled gradient echo imaging technique. Contours derived by the auto-contouring algorithms were compared against manual reference contours. A selection of eight image data sets was also used to assess the inter-observer delineation uncertainty. Algorithmically derived contours agreed well with the manual reference contours (median Dice similarity index: ⩾0.91). Multi-template matching and deformable image registration performed significantly better than feature-driven registration and the pulse-coupled neural network (PCNN). Neither MRI sequence nor image orientation was a conclusive predictor for algorithmic performance. Motion significantly degraded the performance of the PCNN. The inter-observer variability was of the same order of magnitude as the algorithmic performance. Auto-contouring of tumours on cine MRI is feasible in LA lung cancer patients. Despite large variations in implementation complexity, the different algorithms all have relatively similar performance. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  14. Cavernous hemangioma of liver: a comparative study of MRI and color Doppler ultrasound (with 58 case report)

    International Nuclear Information System (INIS)

    Luan Zhiyong; Xu Weidong; Wang Jiazhong

    2006-01-01

    Objective: To evaluate MRI and the color Doppler ultrasound in the diagnosis of cavernous hemangioma of liver. Methods: In total 58 patients with hemangioma of liver underwent dynamic enhanced MRI and the color Doppler ultrasound examination. The imaging manifestations obtained by both modalities were comparatively studied. Result: Highly echoic lesions were revealed in 36 cases out of 58; low echoic lesions were noted in 8; and in 14 cases the tumors were of mixed echoic. On T 1 WI the lesions were hypo- or slightly hypo-intense; while on T 2 WI they were hyper- or slightly hyper-intense. The nidi were hyper-intense on T 2 WI of CRE array. On enhanced scan the lesions were quickly fully enhanced in 25 cases out of 58. Peripheral nodular enhancement was seen in 19 cases, and centered spreading enhancement was demon- strated in 14 cases. On delayed scan remarkable homogenous enhancement was observed in all cases. Conclusion: The bigger size has the hemangioma, the smaller highly echoic proportion and bigger mixed echoic or poorly echoic proportion will be found within the lesions. More peripheral nodular enhancement will be revealed on enhanced MRI scan when the tumor size is getting larger, in which the proportion of quickly fully enhancement will decrease gradually. Ultrasound is better than MRI in the evaluation of the liver hemangioma smaller than 3 cm in diameter. MRI is superior to color Doppler ultrasound in diagnosing the lesion larger' than 3 cm in diameter. (authors)

  15. Tuberculosis versus lymphoma in the abdominal lymph nodes: A comparative study using contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Shao, Heng; Yang, Zhi-gang; Deng, Wen; Chen, Jing; Tang, Si-shi; Wen, Ling-yi

    2012-01-01

    Purpose: The purpose of this study was to determine the differential characteristics on MRI between tuberculosis and lymphoma in abdominal lymph nodes. Materials and methods: We conducted a retrospective analysis for the counter, size, signal intensity, enhancement patterns, and anatomic distribution of lymph nodes in 57 consecutive patients with documented tuberculosis (28 patients; 49.1%) and newly diagnosed, untreated lymphoma (29 patients; 50.9%). Results: Twenty-four cases (85.7%) in the tuberculosis group were hyperintense on T2-weighted images and either hypointense or isointense on T1-weighted images with respect to the abdominal wall muscle. All cases in the lymphoma group were hyperintense on T2-weighted images and isointense on T1-weighted images with respect to the abdominal wall muscle. Concerning the main anatomic distribution of lymph nodes, the lymph nodes in the lower paraaortic region were more frequently involved in the lymphoma group (48.3%) than in tuberculosis (17.9%, p < 0.05). Moreover, mesenteric lymph nodes were more often involved in tuberculosis (32.1%) than in lymphoma (6.9%, p < 0.05). Tuberculous lymphadenopathy showed predominantly peripheral enhancement, frequently with a multilocular appearance; whereas lymphomatous adenopathy often demonstrated uniform homogeneous enhancement (all p < 0.001). Conclusion: Contrast-enhanced MRI can be useful in differentiation between these two entities

  16. Perfusion MRI of brain tumours: a comparative study of pseudo-continuous arterial spin labelling and dynamic susceptibility contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Jaernum, Hanna; Steffensen, Elena G.; Simonsen, Carsten Wiberg; Jensen, Finn Taagehoej [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); Knutsson, Linda [Lund University, Department of Medical Radiation Physics, Lund (Sweden); Fruend, Ernst-Torben [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); GE Healthcare - Applied Science Lab Europe, Aalborg (Denmark); Lundbye-Christensen, Soeren [Aalborg Hospital/Aarhus University Hospital, Department of Cardiology, Center for Cardiovascular Research, Aalborg (Denmark); Shankaranarayanan, Ajit [Global Applied Science Lab, GE Healthcare, Menlo Park, CA (United States); Alsop, David C. [Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA (United States); Larsson, Elna-Marie [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); Uppsala University Hospital, Department of Radiology, Uppsala (Sweden)

    2010-04-15

    The purpose of this study was to compare the non-invasive 3D pseudo-continuous arterial spin labelling (PC ASL) technique with the clinically established dynamic susceptibility contrast perfusion magnetic resonance imaging (DSC-MRI) for evaluation of brain tumours. A prospective study of 28 patients with contrast-enhancing brain tumours was performed at 3 T using DSC-MRI and PC ASL with whole-brain coverage. The visual qualitative evaluation of signal enhancement in tumour was scored from 0 to 3 (0 = no signal enhancement compared with white matter, 3 = pronounced signal enhancement with equal or higher signal intensity than in grey matter/basal ganglia). The extent of susceptibility artefacts in the tumour was scored from 0 to 2 (0 = no susceptibility artefacts and 2 = extensive susceptibility artefacts (maximum diameter > 2 cm)). A quantitative analysis was performed with normalised tumour blood flow values (ASL nTBF, DSC nTBF): mean value for region of interest (ROI) in an area with maximum signal enhancement/the mean value for ROIs in cerebellum. There was no difference in total visual score for signal enhancement between PC ASL and DSC relative cerebral blood flow (p = 0.12). ASL had a lower susceptibility-artefact score than DSC-MRI (p = 0.03). There was good correlation between DSC nTBF and ASL nTBF values with a correlation coefficient of 0.82. PC ASL is an alternative to DSC-MRI for the evaluation of perfusion in brain tumours. The method has fewer susceptibility artefacts than DSC-MRI and can be used in patients with renal failure because no contrast injection is needed. (orig.)

  17. 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.

  18. Safety of meglumine gadoterate (Gd-DOTA)-enhanced MRI compared to unenhanced MRI in patients with chronic kidney disease (RESCUE study)

    Energy Technology Data Exchange (ETDEWEB)

    Deray, Gilbert [Pitie Salpetriere Hospital, Department of Nephrology, Paris cedex 13 (France); Rouviere, Olivier [Hopital E. Herriot, Universite de Lyon, Hospices Civils de Lyon, Department of Urinary and Vascular Imaging, Lyon (France); Universite Lyon 1, faculte de medecine Lyon Est, Lyon (France); Bacigalupo, Lorenzo [E.O. Ospedali Galliera, Radiology Department, Genova (Italy); Maes, Bart [Heilig Hartziekenhuis Roeselare, Department of Nephrology, Roeselare (Belgium); Hannedouche, Thierry [University Hospitals, Department of Nephrology, Strasbourg (France); Vrtovsnik, Francois [Bichat Hospital, Department of Nephrology, Paris (France); Rigothier, Claire [Pellegrin Hospital, Department of Nephrology Transplantation Dialysis, Bordeaux (France); Billiouw, Jean-Marie [Onze Lieve Vrouw Ziekenhuis, Department of Nephrology, Aalst (Belgium); Campioni, Paolo [Azienda Ospedaliero-Universitaria Sant' Anna, Ferrara (Italy); Ferreiros, Joaquin [Hospital Clinico de San Carlos, Servicio de Radiodiagnostico, Madrid (Spain); Devos, Daniel [Gent University Hospital, Department of Radiology, Gent (Belgium); Alison, Daniel [Trousseau Hospital, Department of Radiology, Tours (France); Glowacki, Francois [University Hospitals, Department of Nephrology, Lille (France); Boffa, Jean-Jacques [Tenon Hospital, Department of Nephrology and Dialysis, Paris (France); Marti-Bonmati, Luis [University of Valencia, Department of Radiology, Valencia (Spain)

    2013-05-15

    To prospectively compare the renal safety of meglumine gadoterate (Gd-DOTA)-enhanced magnetic resonance imaging (MRI) to a control group (unenhanced MRI) in high-risk patients. Patients with chronic kidney disease (CKD) scheduled for MRI procedures were screened. The primary endpoint was the percentage of patients with an elevation of serum creatinine levels, measured 72 {+-} 24 h after the MRI procedure, by at least 25 % or 44.2 {mu}mol/l (0.5 mg/dl) from baseline. A non-inferiority margin of the between-group difference was set at -15 % for statistical analysis of the primary endpoint. Main secondary endpoints were the variation in serum creatinine and eGFR values between baseline and 72 {+-} 24 h after MRI and the percentage of patients with a decrease in eGFR of at least 25 % from baseline. Patients were screened for signs of nephrogenic systemic fibrosis (NSF) at 3-month follow-up. Among the 114 evaluable patients, one (1.4 %) in the Gd-DOTA-MRI group and none in the control group met the criteria of the primary endpoint [{Delta} = -1.4 %, 95%CI = (-7.9 %; 6.7 %)]. Non-inferiority was therefore demonstrated (P = 0.001). No clinically significant differences were observed between groups for the secondary endpoints. No serious safety events (including NSF) were noted. Meglumine gadoterate did not affect renal function and was a safe contrast agent in patients with CKD. (orig.)

  19. Safety of meglumine gadoterate (Gd-DOTA)-enhanced MRI compared to unenhanced MRI in patients with chronic kidney disease (RESCUE study)

    International Nuclear Information System (INIS)

    Deray, Gilbert; Rouviere, Olivier; Bacigalupo, Lorenzo; Maes, Bart; Hannedouche, Thierry; Vrtovsnik, Francois; Rigothier, Claire; Billiouw, Jean-Marie; Campioni, Paolo; Ferreiros, Joaquin; Devos, Daniel; Alison, Daniel; Glowacki, Francois; Boffa, Jean-Jacques; Marti-Bonmati, Luis

    2013-01-01

    To prospectively compare the renal safety of meglumine gadoterate (Gd-DOTA)-enhanced magnetic resonance imaging (MRI) to a control group (unenhanced MRI) in high-risk patients. Patients with chronic kidney disease (CKD) scheduled for MRI procedures were screened. The primary endpoint was the percentage of patients with an elevation of serum creatinine levels, measured 72 ± 24 h after the MRI procedure, by at least 25 % or 44.2 μmol/l (0.5 mg/dl) from baseline. A non-inferiority margin of the between-group difference was set at -15 % for statistical analysis of the primary endpoint. Main secondary endpoints were the variation in serum creatinine and eGFR values between baseline and 72 ± 24 h after MRI and the percentage of patients with a decrease in eGFR of at least 25 % from baseline. Patients were screened for signs of nephrogenic systemic fibrosis (NSF) at 3-month follow-up. Among the 114 evaluable patients, one (1.4 %) in the Gd-DOTA-MRI group and none in the control group met the criteria of the primary endpoint [Δ = -1.4 %, 95%CI = (-7.9 %; 6.7 %)]. Non-inferiority was therefore demonstrated (P = 0.001). No clinically significant differences were observed between groups for the secondary endpoints. No serious safety events (including NSF) were noted. Meglumine gadoterate did not affect renal function and was a safe contrast agent in patients with CKD. (orig.)

  20. Achilles tendon (TA) size and power Doppler ultrasound (PD) changes compared to MRI: A preliminary observational study

    International Nuclear Information System (INIS)

    Richards, P.J.; Dheer, A.K.; McCall, I.M.

    2001-01-01

    AIM: To assess whether abnormal Achilles tendon (TA) magnetic resonance imaging (MRI) and spectral ultrasound (US) features have associated development of microvascular power Doppler (PD) flow. MATERIALS AND METHODS: In a prospective, controlled and blinded study six patients with TA symptoms were compared to five with other ankle abnormalities. Two radiologists independently measured the mean maximal anteroposterior diameter on MRI and conventional US (categorized as normal 1.6 cm), assessed morphology and studied the vessels using power Doppler. They formed a consensus over discrepancies. Sonography of the contralateral side within 24 h was used as a control. RESULTS: Twenty-one tendons in six women and five men, aged 45-77 years (mean 57.6 years), were examined, 12 tendons were of normal US morphology and size ( 0.74). Of the 12 tendons studied by MRI five were normal, seven tendons were enlarged, five of which had a proportionate increase in PD flow at the margin on the deep surface and four also had vessels in the centre of the tendon. All five of these tendons had high signal on T2-weighting (T2W). Of the two mildly enlarged tendons of intermediate signal on T1 and T2W, one showed PD flow and the other did not. CONCLUSIONS: In patients with TA disease power Doppler ultrasound shows proliferation of vessels in enlarged, abnormal tendons demonstrated on MRI and standard ultrasound, in the absence of definite tears. Richards, P.J. Dheer, A.K. and McCall, I.M. (2001)

  1. The comparative study of radiograph, MRI and pathology in degeneration of lumbar intervertebral disc

    International Nuclear Information System (INIS)

    Shang Tiesong; Wang Yunzhao

    2002-01-01

    Objective: To investigate the pathology, and MRI features of the degeneration of lumbar intervertebral discs (IVD). Methods: Thirteen human lumbar spine segments with 31 IVDs were harvested from fresh cadavers. High quality radiographs were taken for all specimens. Five segments with 20 IVD underwent MRl. Then, the radiographic and MRI findings were correlated with corresponding 87 pathologic sections. Results: Variant degeneration was observed in pathologic sections in all 31 IVDs. With MRI T 2 WI images, 20 IVDs showed linear and spotty high signal in the annular fibers, or most of the IVD showed high signal. On pathologic cuts, 22 of 31 IVDs showed infolding of annular fibers, 18 of 31 showed outfolding of annular fibers. On MRI T 1 WI and T 2 WI images, infolding and outfolding of annular fibers were seen as low signal. 20 of 31 IVDs had necrotic debris of cells in the nucleus pulposus. 14 of 20 demonstrated spotty low signal areas on MRI T 2 WI images. 7 Schmorl nodules were found. On pathologic sections Schmorl nodules were seen as IVD tissue protruding into vertebral endplates, they were seen as high signal on T 2 WI images. Two large fissures found on sections were seen as low signal on T 2 WI. Degenerative fibrosis seen on 6 IVD, which showed intermediate signal on T 2 WI images. However, radiographs only demonstrated osteophytes on 3 vertebrae, 7 Schmorl's nodules. Sclerotic, concave and irregular endplates were seen in 11 IVDs, the tatter is the indication of cartilaginous endplate disruption, Conclusion: MRI is very useful in demonstrating the degeneration of IVD, radiograph is able to indirectly show the disappearance of cartilaginous endplate

  2. Acute sciatic nerve crush injuries in rabbits: MRI and pathological comparative study

    International Nuclear Information System (INIS)

    Li Xinchun; Chen Jianyu; Wang Xinlu; Shen Jun; Liu Qingyu; Liang Biling

    2004-01-01

    Objective: Simulating injury mechanism in human peripheral nerve, acute sciatic nerve crush injuries model was produced in rabbits to investigate the relationship between the manifestations of MRI and pathology in order to provide the information for clinical therapy and operative plan. Methods: Thirty-two adult rabbits were randomly divided into two groups: group A (n=16) and B (n=16). In group A, the left sciatic nerves were crushed with a stress of 3.61 kg; In group B, with a stress of 10.50 kg. 4 time intervals in each group were observed in 1, 2, 4, and 8 weeks, respectively, and each time interval contained 4 rabbits. Left sciatic nerves were served as injured sides, right sciatic nerves were regarded as control sides. MRI was performed at different time interval after crush injury. Then the nerves were examined pathologically. Results: There were no obvious changes on T 1 WI in injured sides, but the injured distal segment of sciatic nerve thickened and twisted, showing high signal intensity on 3D T 2 WI, T 2 WI/SPIR, B-FFE, and T 2 WI/STIR. MRI could show abnormality of 30 sciatic nerves, the correct diagnostic rate was 93.75% and false negative rate was 6.25%. The distal sciatic nerve/muscle signal intensity ratio (SIR) of the injured sides was significantly higher than that of the control sides (P 0.05). SIR in injured side increased at 1 week, reached the peak at 2 weeks, at this time, nerve axons disappeared and lots of myelin degenerated, abduction function disappeared. SIR decreased during 4-8 weeks, the myelin sheath breakdown and Schwann cell proliferated obviously, and abduction functions were observed. The control sciatic nerves showed no abnormality in MRI and pathology. Conclusion: MRI can make the diagnosis of crush injury of sciatic nerve, and dynamic SIR measurement of nerve injury correlates well with the pathological and functional recovery process. MRI is an effective method to monitor degeneration, regeneration, and prognosis after

  3. COMPARATIVE STUDY BETWEEN THE PUBIS OF ASYMPTOMATIC ATHLETES AND NON-ATHLETES WITH MRI.

    Science.gov (United States)

    Branco, Rodrigo Castelo; da Costa Fontenelle, César Rubens; Miranda, Leandro Marques; Junior, Yonder Archanjo Ching San; Vianna, Evandro Miguelote

    2010-01-01

    To compare the magnetic resonance imaging findings from the pubis of professional soccer players without any history or clinical findings of groin pain, and from sedentary individuals, also without symptoms, and to determine the prevalence of changes compatible with pubic overload. Nineteen professional soccer players without complaints of groin pain and seventeen sedentary individuals, also asymptomatic, underwent magnetic resonance imaging of the pubis. The results from the examinations were analyzed regarding the presence of degenerative changes, boned medullary edema and tendinopathy, and the two study groups were compared. High prevalence of bone edema, tendinopathy and degenerative findings in the pubic symphysis was seen in the athletes, with statistically significant higher odds ratios and relative risk in the population studied. Professional soccer players are at a higher risk of developing changes in the pubic region, shown in magnetic resonance images, compared with sedentary individuals. These findings are not necessarily caused by groin pain, and are probably related to intense exertion.

  4. MRI comparative study of the progressive supranuclear palsy, striatonigral degeneration and Parkinson disease

    International Nuclear Information System (INIS)

    Wu Wulin; Lou Mingwu; Wang Xiaoyi; Liao Weihua

    2009-01-01

    Objective: To provide a reliable differential diagnosis among the progressive supranuclear palsy (PSP), striatonigral degeneration (SND) and Parkinson disease (PD). Methods: Conventional MRI data in clinically proved PSP (8 cases), SND (9 cases), PD (12 cases) and 12 normal controls were retrospectively analyzed. Midbrain area, pons area, pons diameter and middle cerebellar peduncles width were measured. The ratio of pons area over midbrain area (pons area / midbrain area) was calculated in all patients and normal controls. Then one way ANOVA and a Kruskal-Wallis H test were used for statistical analysis. Results: Midbrain area of the PSP group [(85.8 ± 12.0 mm 2 ] was the smallest, and there was statistically significant difference (P 2 ], PD group [(133.5 ± 10.8)mm 2 ] and the control group [(135.9 ± 7.5) mm 2 ]. There was no overlapping in the distribution of midbrain area between the PSP group (66.0-98.2 mm 2 ) and SND, PD and normal groups (116.2-142.1, 110.8-146.2 and 121.7-145.8 mm 2 ). The pons area-midbrain area ratio (P/M) of the PSP group (5.9 ± 0.8) was the largest in four groups, and there was statistically significant difference (P 2 , (18.6 ± 2.0) mm and (12.9 ± 2.4) mm] in all groups, and significant difference (P 2 , (22.7 ± 1.7) mm and (16.3 ± 1.1) mm], PD group [3.8 ± 0.3, (500.2 ± 25.8) mm 2 , (23.7 ± 1.0) mm and (16.8 ± 1.1) mm] and the control group [3.8 ± 0.3, (508.8 ± 20.6) mm 2 , (23.2 ± 1.2) mm and (16.4 ± 0.9) mm]. But the PD group and control group had no statistically significant difference in the midbrain area, pons area, pons diameter, P/M and middle cerebellar peduncles width (P > 0.05). Conclusion: MRI measurements helps in the differential diagnosis among PSP, SND and PD. (authors)

  5. MRI pattern of arthritis in systemic lupus erythematosus: a comparative study with rheumatoid arthritis and healthy subjects

    Energy Technology Data Exchange (ETDEWEB)

    Tani, Chiara; Possemato, Niccolo; Delle Sedie, Andrea; Bombardieri, Stefano; Mosca, Marta [University of Pisa, Rheumatology Unit, Department of Clinical and Experimental Medicine, Pisa (Italy); D' aniello, Dario; Caramella, Davide [Radiology Unit, University of Pisa, Pisa (Italy)

    2014-10-24

    In this study we aimed to describe the magnetic resonance imaging (MRI) pattern of the distribution of bone marrow edema (BME) and joint erosion in hands and wrists of patients with systemic lupus erythematosus (SLE) with arthritis in comparison with rheumatoid arthritis (RA) and healthy subjects (H). SLE patients with arthritis (n = 50), patients with RA (n = 22), and H (n = 48) were enrolled. Every patient underwent a non-dominant hand (2nd-5th metacarpophalangeal joints) and wrist MRI without contrast injection with a low-field extremity dedicated 0.2-Tesla instrument. BME was observed in two SLE patients in the hand (4 %) and in 15 in the wrist (13 %) versus three (30 %), and 14 (63 %) RA patients. No BME was found in H. Erosions were observed in the hand in 24 SLE patients (48 %), 15 RA patients (68 %), and 9 H (18 %); in the wrist, in 41 (82 %) SLE, all RA and 47 (97 %) H. The cumulative erosive burden in SLE was significantly higher than in H (c = 0.002) but similar to RA patients. Joint involvement of the wrist in SLE is similar to RA and is not as rare as expected, as shown by the comparison with healthy subjects. On the contrary, the involvement of the hand in SLE is significantly lower compared to RA. (orig.)

  6. MRI pattern of arthritis in systemic lupus erythematosus: a comparative study with rheumatoid arthritis and healthy subjects

    International Nuclear Information System (INIS)

    Tani, Chiara; Possemato, Niccolo; Delle Sedie, Andrea; Bombardieri, Stefano; Mosca, Marta; D'aniello, Dario; Caramella, Davide

    2015-01-01

    In this study we aimed to describe the magnetic resonance imaging (MRI) pattern of the distribution of bone marrow edema (BME) and joint erosion in hands and wrists of patients with systemic lupus erythematosus (SLE) with arthritis in comparison with rheumatoid arthritis (RA) and healthy subjects (H). SLE patients with arthritis (n = 50), patients with RA (n = 22), and H (n = 48) were enrolled. Every patient underwent a non-dominant hand (2nd-5th metacarpophalangeal joints) and wrist MRI without contrast injection with a low-field extremity dedicated 0.2-Tesla instrument. BME was observed in two SLE patients in the hand (4 %) and in 15 in the wrist (13 %) versus three (30 %), and 14 (63 %) RA patients. No BME was found in H. Erosions were observed in the hand in 24 SLE patients (48 %), 15 RA patients (68 %), and 9 H (18 %); in the wrist, in 41 (82 %) SLE, all RA and 47 (97 %) H. The cumulative erosive burden in SLE was significantly higher than in H (c = 0.002) but similar to RA patients. Joint involvement of the wrist in SLE is similar to RA and is not as rare as expected, as shown by the comparison with healthy subjects. On the contrary, the involvement of the hand in SLE is significantly lower compared to RA. (orig.)

  7. Comparative imaging study in ultrasound, MRI, CT, and DSA using a multimodality renal artery phantom

    Energy Technology Data Exchange (ETDEWEB)

    King, Deirdre M.; Fagan, Andrew J.; Moran, Carmel M.; Browne, Jacinta E. [Medical Ultrasound Physics and Technology Group, School of Physics, Dublin Institute of Technology, Dublin 8 (Ireland); Centre for Advanced Medical Imaging (CAMI), St James' s Hospital, Dublin 8 (Ireland); Department of Medical Physics, University of Edinburgh, Edinburgh EH16 4TJ (United Kingdom); Medical Ultrasound Physics and Technology Group, School of Physics, Dublin Institute of Technology, Dublin 8 (Ireland)

    2011-02-15

    to allow for quantitative measurements of the degree of stenosis in each phantom. Such multimodality phantoms may prove useful in evaluating current and emerging US, MRI, CT, and DSA technology.

  8. Comparative imaging study in ultrasound, MRI, CT, and DSA using a multimodality renal artery phantom

    International Nuclear Information System (INIS)

    King, Deirdre M.; Fagan, Andrew J.; Moran, Carmel M.; Browne, Jacinta E.

    2011-01-01

    for quantitative measurements of the degree of stenosis in each phantom. Such multimodality phantoms may prove useful in evaluating current and emerging US, MRI, CT, and DSA technology.

  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. Is the body-coil at 3 Tesla feasible for the MRI evaluation of the painful knee? A comparative study

    International Nuclear Information System (INIS)

    Lutterbey, G.; Behrends, K.; Falkenhausen, M.V.; Wattjes, M.P.; Morakkabati, N.; Schild, H.; Gieseke, J.

    2007-01-01

    The purpose of this study was to compare the in-built body coil of the 3.0-Tesla (T) scanner with a dedicated surface coil of a 1.5 T system regarding knee imaging. We performed an intraindividual prospective clinical trial on 17 patients with knee pain using magnetic resonance imaging (MRI) at 1.5 and 3.0 T systems equipped with identical gradient systems. Proton-density-weighted turbo spin echo sequences with the same spatial resolution and comparable contrast parameters were used. A quantitative measurement of signal to noise ratio (SNR), relative contrast (RC) and contrast to noise ratio (CNR) between muscle and bone marrow was performed, followed by a qualitative assessment of anatomic/pathologic structures and the extent of artefacts. At 3.0 T, 30 lesions (91%) compared to 33 lesions at 1.5 T were detected. The SNR/CNR/RC were moderately reduced at 3.0 T versus 1.5 T (muscle 42 vs 47 and bone 83 vs 112/46 vs 69/0.33 vs 0.43). Motion artefacts from the pulsating popliteal artery were significantly increased at 3.0 T. A visible and measurable signal loss occurred at 3.0 T using the built-in body coil compared with the dedicated 1.5 T knee coil, but nearly all clinically important information could be obtained. (orig.)

  11. Is the body-coil at 3 Tesla feasible for the MRI evaluation of the painful knee? A comparative study.

    Science.gov (United States)

    Lutterbey, G; Behrends, K; Falkenhausen, M V; Wattjes, M P; Morakkabati, N; Gieseke, J; Schild, H

    2007-02-01

    The purpose of this study was to compare the in-built body coil of the 3.0-Tesla (T) scanner with a dedicated surface coil of a 1.5 T system regarding knee imaging. We performed an intraindividual prospective clinical trial on 17 patients with knee pain using magnetic resonance imaging (MRI) at 1.5 and 3.0 T systems equipped with identical gradient systems. Proton-density-weighted turbo spin echo sequences with the same spatial resolution and comparable contrast parameters were used. A quantitative measurement of signal to noise ratio (SNR), relative contrast (RC) and contrast to noise ratio (CNR) between muscle and bone marrow was performed, followed by a qualitative assessment of anatomic/pathologic structures and the extent of artefacts. At 3.0 T, 30 lesions (91%) compared to 33 lesions at 1.5 T were detected. The SNR/CNR/RC were moderately reduced at 3.0 T versus 1.5 T (muscle 42 vs 47 and bone 83 vs 112/46 vs 69/0.33 vs 0.43). Motion artefacts from the pulsating popliteal artery were significantly increased at 3.0 T. A visible and measurable signal loss occurred at 3.0 T using the built-in body coil compared with the dedicated 1.5 T knee coil, but nearly all clinically important information could be obtained.

  12. Comparing TMS perturbations to occipital and parietal cortices in concurrent TMS-fMRI studies-Methodological considerations

    DEFF Research Database (Denmark)

    Leitao, Joana; Thielscher, Axel; Tuennerhoff, Johannes

    2017-01-01

    the effect of transient perturbations on functional brain organization. This concurrent TMS-fMRI study applied TMS perturbation to occipital and parietal cortices with the aim to 'mimick' neglect and hemianopia. Based on the challenges and interpretational limitations of our own study we aim to provide...

  13. Comparative study of diffusion weighted imaging and dynamic contrast enhanced MRI for the detection of small breast cancers

    International Nuclear Information System (INIS)

    Tang Jianhua; Yan Fuhua; Zhou Meiling; Ye Fang; Xu Pengju

    2008-01-01

    Objective: To compare the sensitivity of diffusion weighted imaging (DWI) with dynamic contrast enhanced (DCE) MRI for the detection of small breast cancers and to evaluate the clinical value of DWI. Methods: Forty-eight patients with benign (n=25) and malignant (n=45) small breast lesions (≤2 cm) proved by pathology underwent DWI and DCE MRI. The DCE MRI was performed using FLASH sequence and the time-signal intensity curve was drawn. The DWI was performed using GRAPPA- EPI sequence with different b values (800, 1000 s/mm 2 ) and the ADC values of lesions were measured. The sensitivity and specificity of DWI for the detection of small breast cancers were compared with DCE MRI. Results: Forty of 45 small breast cancers and 19 of 25 small benign breast lesions were correctly diagnosed using DCE MRI. The sensitivity and positive predictive value of TIC were 88.9% (40/45) and 87.0% (40/46). With b values of 800 s/mm 2 and 1000 s/mm 2 , the average ADC values of small breast cancers were (1.153±0.192) x 10 -3 and (1.079±0.186) x 10 -3 mm 2 /s, while those of benign ones were (1.473±0.252) x 10 -3 and (1.419 ± 0.255) x 10 -3 mm 2 /s, respectively. There was no significant difference for the ADC values with different b values in the same group (P>0.05), while there was a significant difference between the malignant and the benign lesions (P 2 . Both the sensitivity and positive predictive value of diagnosis were 86.7% (39/45). The abilities of DWI and DCE MRI for the diagnosis of small breast cancers were the same. The sensitivity (93.3%) and positive predictive value (91.3%) were improved with the combination of DCE MRI and DWI. Conclusion: DWI has a high sensitivity for the detection of small breast cancers, the ADC value can provide valuable information in the differential diagnosis. (authors)

  14. 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

  15. Usefulness of breast-specific gamma imaging as an adjunct modality in breast cancer patients with dense breast. A comparative study with MRI

    International Nuclear Information System (INIS)

    Kim, Bom Sahn

    2012-01-01

    The aim of this study was to evaluate the adjunctive benefits of breast-specific gamma imaging (BSGI) versus magnetic resonance imaging (MRI) in breast cancer patients with dense breasts. This study included a total of 66 patients (44.1±8.2 years) with dense breasts (breast density >50%) and already biopsy-confirmed breast cancer. All of the patients underwent BSGI and MRI as part of an adjunct modality before the initial therapy. Of 66 patients, the 97 undetermined breast lesions were newly detected and correlated with the biopsy results. Twenty-six of the 97 breast lesions proved to be malignant tumors (invasive ductal cancer, n=16; ductal carcinoma in situ, n=6; mixed or other malignancies, n=4); the remaining 71 lesions were diagnosed as benign tumors. The sensitivity and specificity of BSGI were 88.8% (confidence interval (CI), 69.8-97.6%) and 90.1% (CI, 80.7-95.9%), respectively, while the sensitivity and specificity of MRI were 92.3% (CI, 74.9-99.1%) and 39.4% (CI, 28.0-51.7%), respectively (p<0.0001). MRI detected 43 false-positive breast lesions, 37 (86.0%) of which were correctly diagnosed as benign lesions using BSGI. In 12 malignant lesions <1 cm, the sensitivities of BSGI and MR imaging were 83.3% (CI, 51.6-97.9%) and 91.7% (CI, 61.5-99.8%), respectively. BSGI showed an equivocal sensitivity and a high specificity compared to MRI in the diagnosis of breast lesions. In addition, BSGI had a good sensitivity in discriminating breast cancers ≤1 cm. The results of this study suggest that BSGI could play a crucial role as an adjunctive imaging modality which can be used to evaluate breast cancer patients with dense breasts. (author)

  16. Alterations of the transverse ligament: an MRI study comparing patients with acute whiplash and matched control subjects.

    Science.gov (United States)

    Ulbrich, Erika Jasmin; Eigenheer, Sandra; Boesch, Chris; Hodler, Juerg; Busato, André; Schraner, Christian; Anderson, Suzanne E; Bonel, Harald; Zimmermann, Heinz; Sturzenegger, Matthias

    2011-10-01

    The objective of our study was to evaluate whether there is injury to the transverse ligament of the atlas in patients with acute whiplash. Ninety patients with an acute (transverse ligament was measured on midsagittal T1 volumetric interpolated breath-hold examination (VIBE) images and transverse reformatted VIBE images. The signal intensity of the transverse ligament was measured on transverse STIR images and on transverse reformatted T1 VIBE images before and after IV administration of gadoterate. Contrast between the transverse ligament and CSF and alterations of contrast after gadoterate injection were calculated. Patients had a minimally thicker transverse ligament (posttraumatic swelling) than control subjects, and the difference in thickness was significant in men only (p = 0.03). In patients, a significant signal alteration of the transverse ligament (p = 0.03) was seen on STIR (posttraumatic edema) and native VIBE sequences. The contrast between the transverse ligament and the CSF on VIBE images was significantly (p = 0.005) lower in patients than in control subjects. With the application of a contrast agent, the contrast difference between the transverse ligament and CSF in patients and control subjects was less pronounced (p = 0.038). There was no abnormal uptake of contrast agent by the transverse ligament or CSF. The results of our study indicate possible involvement of the transverse ligament in whiplash injury. Although MRI may be helpful to study injury-related changes of anatomic structures in cohorts, it is not suited for individual diagnosis because the alterations are too small.

  17. Visual search for feature conjunctions: an fMRI study comparing alcohol-related neurodevelopmental disorder (ARND) to ADHD.

    Science.gov (United States)

    O'Conaill, Carrie R; Malisza, Krisztina L; Buss, Joan L; Bolster, R Bruce; Clancy, Christine; de Gervai, Patricia Dreessen; Chudley, Albert E; Longstaffe, Sally

    2015-01-01

    Alcohol-related neurodevelopmental disorder (ARND) falls under the umbrella of fetal alcohol spectrum disorder (FASD). Diagnosis of ARND is difficult because individuals do not demonstrate the characteristic facial features associated with fetal alcohol syndrome (FAS). While attentional problems in ARND are similar to those found in attention-deficit/hyperactivity disorder (ADHD), the underlying impairment in attention pathways may be different. Functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) was conducted at 3 T. Sixty-three children aged 10 to 14 years diagnosed with ARND, ADHD, and typically developing (TD) controls performed a single-feature and a feature-conjunction visual search task. Dorsal and ventral attention pathways were activated during both attention tasks in all groups. Significantly greater activation was observed in ARND subjects during a single-feature search as compared to TD and ADHD groups, suggesting ARND subjects require greater neural recruitment to perform this simple task. ARND subjects appear unable to effectively use the very efficient automatic perceptual 'pop-out' mechanism employed by TD and ADHD groups during presentation of the disjunction array. By comparison, activation was lower in ARND compared to TD and ADHD subjects during the more difficult conjunction search task as compared to the single-feature search. Analysis of DTI data using tract-based spatial statistics (TBSS) showed areas of significantly lower fractional anisotropy (FA) and higher mean diffusivity (MD) in the right inferior longitudinal fasciculus (ILF) in ARND compared to TD subjects. Damage to the white matter of the ILF may compromise the ventral attention pathway and may require subjects to use the dorsal attention pathway, which is associated with effortful top-down processing, for tasks that should be automatic. Decreased functional activity in the right temporoparietal junction (TPJ) of ARND subjects may be due to a

  18. Experimental study of sector and linear array ultrasound accuracy and the influence of navigated 3D-reconstruction as compared to MRI in a brain tumor model.

    Science.gov (United States)

    Siekmann, Max; Lothes, Thomas; König, Ralph; Wirtz, Christian Rainer; Coburger, Jan

    2018-03-01

    Currently, intraoperative ultrasound in brain tumor surgery is a rapidly propagating option in imaging technology. We examined the accuracy and resolution limits of different ultrasound probes and the influence of 3D-reconstruction in a phantom and compared these results to MRI in an intraoperative setting (iMRI). An agarose gel phantom with predefined gel targets was examined with iMRI, a sector (SUS) and a linear (LUS) array probe with two-dimensional images. Additionally, 3D-reconstructed sweeps in perpendicular directions were made of every target with both probes, resulting in 392 measurements. Statistical calculations were performed, and comparative boxplots were generated. Every measurement of iMRI and LUS was more precise than SUS, while there was no apparent difference in height of iMRI and 3D-reconstructed LUS. Measurements with 3D-reconstructed LUS were always more accurate than in 2D-LUS, while 3D-reconstruction of SUS showed nearly no differences to 2D-SUS in some measurements. We found correlations of 3D-reconstructed SUS and LUS length and width measurements with 2D results in the same image orientation. LUS provides an accuracy and resolution comparable to iMRI, while SUS is less exact than LUS and iMRI. 3D-reconstruction showed the potential to distinctly improve accuracy and resolution of ultrasound images, although there is a strong correlation with the sweep direction during data acquisition.

  19. Juvenile spondylolysis: a comparative analysis of CT, SPECT and MRI

    International Nuclear Information System (INIS)

    Campbell, R.S.D.; Grainger, A.J.; Hide, I.G.; Papastefanou, S.; Greenough, C.G.

    2005-01-01

    To evaluate whether MRI correlates with CT and SPECT imaging for the diagnosis of juvenile spondylolysis, and to determine whether MRI can be used as an exclusive image modality. Juveniles and young adults with a history of extension low back pain were evaluated by MRI, CT and SPECT imaging. All images were reviewed blindly. Correlative analyses included CT vs MRI for morphological grading and SPECT vs MRI for functional grading. Finally, an overall grading system compared MRI vs CT and SPECT combined. Statistical analysis was performed using the kappa statistic. Seventy-two patients (mean age 16 years) were recruited. Forty pars defects were identified in 22 patients (31%), of which 25 were chronic non-union, five acute complete defects and ten acute incomplete fractures. Kappa scores demonstrated a high level of agreement for all comparative analyses. MRI vs SPECT (kappa: 0.794), MRI vs CT (kappa: 0.829) and MRI vs CT/SPECT (kappa: 0.786). The main causes of discrepancy were between MRI and SPECT for the diagnosis of stress reaction in the absence of overt fracture, and distinguishing incomplete fractures from intact pars or complete defects. MRI can be used as an effective and reliable first-line image modality for diagnosis of juvenile spondylolysis. However, localised CT is recommended as a supplementary examination in selected cases as a baseline for assessment of healing and for evaluation of indeterminate cases. (orig.)

  20. Juvenile spondylolysis: a comparative analysis of CT, SPECT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, R.S.D. [Royal Liverpool University Hospital, Department of Radiology, Liverpool (United Kingdom); Grainger, A.J. [Leeds General Infirmary, Department of Radiology, Leeds (United Kingdom); Hide, I.G. [Freeman Hospital, Department of Radiology, Newcastle upon Tyne (United Kingdom); Papastefanou, S. [James Cook University Hospital, Department Radiology, Middlesbrough (United Kingdom); Greenough, C.G. [James Cook University Hospital, Department of Trauma and Orthopaedics, Middlesbrough (United Kingdom)

    2005-02-01

    To evaluate whether MRI correlates with CT and SPECT imaging for the diagnosis of juvenile spondylolysis, and to determine whether MRI can be used as an exclusive image modality. Juveniles and young adults with a history of extension low back pain were evaluated by MRI, CT and SPECT imaging. All images were reviewed blindly. Correlative analyses included CT vs MRI for morphological grading and SPECT vs MRI for functional grading. Finally, an overall grading system compared MRI vs CT and SPECT combined. Statistical analysis was performed using the kappa statistic. Seventy-two patients (mean age 16 years) were recruited. Forty pars defects were identified in 22 patients (31%), of which 25 were chronic non-union, five acute complete defects and ten acute incomplete fractures. Kappa scores demonstrated a high level of agreement for all comparative analyses. MRI vs SPECT (kappa: 0.794), MRI vs CT (kappa: 0.829) and MRI vs CT/SPECT (kappa: 0.786). The main causes of discrepancy were between MRI and SPECT for the diagnosis of stress reaction in the absence of overt fracture, and distinguishing incomplete fractures from intact pars or complete defects. MRI can be used as an effective and reliable first-line image modality for diagnosis of juvenile spondylolysis. However, localised CT is recommended as a supplementary examination in selected cases as a baseline for assessment of healing and for evaluation of indeterminate cases. (orig.)

  1. Comparative study of image quality between axial T2-weighted BLADE and turbo spin-echo MRI of the upper abdomen on 3.0 T.

    Science.gov (United States)

    Zhang, Lin; Tian, ChunMei; Wang, PeiYuan; Chen, Liang; Mao, XiJin; Wang, ShanShan; Wang, Xu; Dong, JingMin; Wang, Bin

    2015-09-01

    To compare image quality of turbo spin-echo (TSE) with BLADE [which is also named periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER)] on magnetic resonance imaging (MRI) for upper abdomen. This study involved the retrospective evaluation of 103 patients (63 males, 40 females; age range 19-76 years; median age 53.8 years) who underwent 3.0 T MRI with both conventional TSE T2-weighted imaging (T2WI) and BLADE TSE T2WI. Two radiologists assessed respiratory motion, gastrointestinal peristalsis, and vascular pulsation artifacts, as well as the sharpness of the liver and pancreas edges. Scores for all magnetic resonance (MR) images were recorded. Wilcoxon's rank test was used to compare hierarchical data. Cohen's kappa coefficient was adopted to analyze interobserver consistency. Compared to TSE T2WI, BLADE TSE T2WI reduced all of the examined motion artifacts and increased the sharpness of the liver and pancreas edges (all P image quality.

  2. Lateral cephalometric analysis for treatment planning in orthodontics based on MRI compared with radiographs: A feasibility study in children and adolescents.

    Science.gov (United States)

    Heil, Alexander; Lazo Gonzalez, Eduardo; Hilgenfeld, Tim; Kickingereder, Philipp; Bendszus, Martin; Heiland, Sabine; Ozga, Ann-Kathrin; Sommer, Andreas; Lux, Christopher J; Zingler, Sebastian

    2017-01-01

    The objective of this prospective study was to evaluate whether magnetic resonance imaging (MRI) is equivalent to lateral cephalometric radiographs (LCR, "gold standard") in cephalometric analysis. The applied MRI technique was optimized for short scanning time, high resolution, high contrast and geometric accuracy. Prior to orthodontic treatment, 20 patients (mean age ± SD, 13.95 years ± 5.34) received MRI and LCR. MRI datasets were postprocessed into lateral cephalograms. Cephalometric analysis was performed twice by two independent observers for both modalities with an interval of 4 weeks. Eight bilateral and 10 midsagittal landmarks were identified, and 24 widely used measurements (14 angles, 10 distances) were calculated. Statistical analysis was performed by using intraclass correlation coefficient (ICC), Bland-Altman analysis and two one-sided tests (TOST) within the predefined equivalence margin of ± 2°/mm. Geometric accuracy of the MRI technique was confirmed by phantom measurements. Mean intraobserver ICC were 0.977/0.975 for MRI and 0.975/0.961 for LCR. Average interobserver ICC were 0.980 for MRI and 0.929 for LCR. Bland-Altman analysis showed high levels of agreement between the two modalities, bias range (mean ± SD) was -0.66 to 0.61 mm (0.06 ± 0.44) for distances and -1.33 to 1.14° (0.06 ± 0.71) for angles. Except for the interincisal angle (p = 0.17) all measurements were statistically equivalent (p feasibility of orthodontic treatment planning without radiation exposure based on MRI. High-resolution isotropic MRI datasets can be transformed into lateral cephalograms allowing reliable measurements as applied in orthodontic routine with high concordance to the corresponding measurements on LCR.

  3. Coronary artery size and origin imaging in children: a comparative study of MRI and trans-thoracic echocardiography

    International Nuclear Information System (INIS)

    Hussain, Tarique; Mathur, Sujeev; Peel, Sarah A.; Valverde, Israel; Bilska, Karolina; Henningsson, Markus; Botnar, Rene M.; Simpson, John; Greil, Gerald F.

    2015-01-01

    The purpose of this study was to see how coronary magnetic resonance angiography (CMRA) compared to echocardiography for the detection of coronary artery origins and to compare CMRA measurements for coronary dimensions in children with published echocardiographic reference values. Enrolled patients underwent dual cardiac phase CMRA and echocardiography under the same anesthetic. Echocardiographic measurements of the right coronary artery (RCA), left anterior descending (LAD) and left main (LM) were made. CMRA dimensions were assessed manually at the same points as the echocardiographic measurements. The number of proximal LAD branches imaged was also recorded in order to give an estimate of distal coronary tree visualization. Fifty patients (24 boys, mean age 4.0 years (range 18 days to 18 years)) underwent dual-phase CMRA. Coronary origins were identified in 47/50 cases for CMRA (remaining 3 were infants aged 3, 9 and 11 months). In comparison, origins were identified in 41/50 cases for echo (remaining were all older children). CMRA performed better than echocardiography in terms of distal visualization of the coronary tree (median 1 LAD branch vs. median 0; p = 0.001). Bland-Altman plots show poor agreement between echocardiography and CMRA for coronary measurements. CMRA measurements did vary according to cardiac phase (systolic mean 1.90, s.d. 0.05 mm vs. diastolic mean 1.84, s.d. 0.05 mm; p = 0.002). Dual-phase CMRA has an excellent (94 %) success rate for the detection of coronary origins in children. Newborn infants remain challenging and echocardiography remains the accepted imaging modality for this age group. Echocardiographic reference ranges are not applicable to CMRA measurements as agreement was poor between modalities. Future coronary reference values, using any imaging modality, should quote the phase in which it was measured

  4. Osteitis: a retrospective feasibility study comparing single-source dual-energy CT to MRI in selected patients with suspected acute gout

    Energy Technology Data Exchange (ETDEWEB)

    Diekhoff, Torsten [Humboldt-Universitaet zu Berlin, Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Berlin (Germany); Charite - Universitaetsmedizin Berlin, Department of Radiology (CCM), Berlin (Germany); Scheel, Michael; Hamm, Bernd; Hermann, Kay-Geert A. [Humboldt-Universitaet zu Berlin, Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Berlin (Germany); Hermann, Sandra [Charite - Universitaetsmedizin Berlin Campus Mitte, Department of Rheumatology and Clinical Immunology, Berlin (Germany); Mews, Juergen [Toshiba Medical Systems Europe, BV, Zoetermeer (Netherlands)

    2017-02-15

    Dual-energy computed tomography detects tophi in patients with chronic gout. However, other information that can be obtained from the same scan is not the focus of the current research, e.g., the detection of bone marrow edema (BME) using virtual bone marrow imaging (VBMI). The aim of this study was to evaluate if BME in patients with acute arthritis can be detected with VBMI using magnetic resonance imaging (MRI) as the standard of reference. This retrospective study included 11 patients who underwent both MRI and dual-energy computed tomography (mean interval of 40 days). BME in MRI (standard of reference) and VBMI was judged independently by two different blinded readers. φ-correlation coefficient and Cohen's κ were performed for statistical analysis. Approval was waived by the IRB. Two patients with a final diagnosis of RA and one with septic arthritis showed osteitis on MRI and VBMI. However, in each case, there were individual bones identified with osteitis on MRI but not VBMI. Three additional patients with the final diagnosis of RA were identified correctly as negative for BME. There was a good correlation between both modalities (φ = 0.8; κ = 0.8). Inter-rater reliability was excellent for both modalities (κ = 0.9). We have shown that detecting osteitis using VBMI is feasible in patients with inflammatory arthritis. Further studies are needed on larger, more-targeted populations to better define the indications, accuracy, and added value of this technique. (orig.)

  5. Osteitis: a retrospective feasibility study comparing single-source dual-energy CT to MRI in selected patients with suspected acute gout

    International Nuclear Information System (INIS)

    Diekhoff, Torsten; Scheel, Michael; Hamm, Bernd; Hermann, Kay-Geert A.; Hermann, Sandra; Mews, Juergen

    2017-01-01

    Dual-energy computed tomography detects tophi in patients with chronic gout. However, other information that can be obtained from the same scan is not the focus of the current research, e.g., the detection of bone marrow edema (BME) using virtual bone marrow imaging (VBMI). The aim of this study was to evaluate if BME in patients with acute arthritis can be detected with VBMI using magnetic resonance imaging (MRI) as the standard of reference. This retrospective study included 11 patients who underwent both MRI and dual-energy computed tomography (mean interval of 40 days). BME in MRI (standard of reference) and VBMI was judged independently by two different blinded readers. φ-correlation coefficient and Cohen's κ were performed for statistical analysis. Approval was waived by the IRB. Two patients with a final diagnosis of RA and one with septic arthritis showed osteitis on MRI and VBMI. However, in each case, there were individual bones identified with osteitis on MRI but not VBMI. Three additional patients with the final diagnosis of RA were identified correctly as negative for BME. There was a good correlation between both modalities (φ = 0.8; κ = 0.8). Inter-rater reliability was excellent for both modalities (κ = 0.9). We have shown that detecting osteitis using VBMI is feasible in patients with inflammatory arthritis. Further studies are needed on larger, more-targeted populations to better define the indications, accuracy, and added value of this technique. (orig.)

  6. 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)

  7. Normalized wall index specific and MRI-based stress analysis of atherosclerotic carotid plaques. A study comparing acutely symptomatic and asymptomatic patients

    International Nuclear Information System (INIS)

    Zhu, C.; Teng, Z.; Sadat, U.; Young, V.E.; Graves, M.J.; Gillard, J.H.; Li Zhiyong

    2010-01-01

    Biomechanical stresses play an important role in determining plaque stability. Quantification of these simulated stresses can be potentially used to assess plaque vulnerability and differentiate different patient groups. 54 asymptomatic and 45 acutely symptomatic patients underwent in vivo multicontrast magnetic resonance imaging (MRI) of the carotid arteries. Plaque geometry used for finite element analysis was derived from in vivo MRI at the sites of maximum and minimum plaque burden. In total, 198 slices were used for the computational simulations. A pre-shrink technique was used to refine the simulation. Maximum principle stress at the vulnerable plaque sites (id est (ie), critical stress) was extracted for the selected slices and a comparison was performed between the 2 groups. Critical stress in the slice with maximum plaque burden is significantly higher in acutely symptomatic patients as compared to asymptomatic patients (median, inter quartile range: 198.0 kPa (119.8-359.0 kPa) vs 138.4 kPa (83.8-242.6 kPa), P=0.04). No significant difference was found in the slice with minimum plaque burden between the 2 groups (196.7 kPa (133.3-282.7 kPa) vs 182.4 kPa (117.2-310.6 kPa), P=0.82). Acutely symptomatic carotid plaques have significantly high biomechanical stresses than asymptomatic plaques. This might be potentially useful for establishing a biomechanical risk stratification criteria based on plaque burden in future studies. (author)

  8. Neural reactivity to visual food stimuli is reduced in some areas of the brain during evening hours compared to morning hours: an fMRI study in women.

    Science.gov (United States)

    Masterson, Travis D; Kirwan, C Brock; Davidson, Lance E; LeCheminant, James D

    2016-03-01

    The extent that neural responsiveness to visual food stimuli is influenced by time of day is not well examined. Using a crossover design, 15 healthy women were scanned using fMRI while presented with low- and high-energy pictures of food, once in the morning (6:30-8:30 am) and once in the evening (5:00-7:00 pm). Diets were identical on both days of the fMRI scans and were verified using weighed food records. Visual analog scales were used to record subjective perception of hunger and preoccupation with food prior to each fMRI scan. Six areas of the brain showed lower activation in the evening to both high- and low-energy foods, including structures in reward pathways (P foods compared to low-energy foods (P food stimuli tended to produce greater fMRI responses than low-energy food stimuli in specific areas of the brain, regardless of time of day. However, evening scans showed a lower response to both low- and high-energy food pictures in some areas of the brain. Subjectively, participants reported no difference in hunger by time of day (F = 1.84, P = 0.19), but reported they could eat more (F = 4.83, P = 0.04) and were more preoccupied with thoughts of food (F = 5.51, P = 0.03) in the evening compared to the morning. These data underscore the role that time of day may have on neural responses to food stimuli. These results may also have clinical implications for fMRI measurement in order to prevent a time of day bias.

  9. Differences between head CT and MRI for selecting patients for intravenous rt-PA during hyperacute brain infarction. Comparative study of intracranial bleeding complications and prognosis

    International Nuclear Information System (INIS)

    Deguchi, Ichiro; Takeda, Hidetaka; Furuya, Daisuke

    2010-01-01

    The objective of this study was to investigate the differences in usefulness between head CT and MRI for selecting patients for intravenous injection of recombinant tissue plasminogen activator (rt-PA) during hyperacute brain infarction. Of a total of 1280 brain infarction patients who were admitted from October 2005 to March 2009, 45 patients (33 men and 12 women with an average age of 69.2±11.6 years) received intravenous rt-PA. Of these, 16 patients in whom only head CT was performed (593 inpatients from October 2005 to March 2007, CT standard group, 11 men and 5 women, average age 67.4±15.4 years) and 29 patients in whom head CT and MRI were performed (687 inpatients from April 2007 to March 2009, MRI standard group, 21 men and 7 women, average age 70.1±9.0 years) were studied. The median National Institutes of Health Stroke Scale (NIHSS) scores immediately before intravenous rt-PA for the CT and MRI standard groups were 19 and 11, respectively; disease severity was lower for the MRI standard group. Three months later, the modified Rankin Scale (mRS) score for the MRI standard group (0-1: 31%, 2-3: 38%, 4-5: 24%, and 6: 12%) was better than for the CT standard group (0-1: 25%, 2-3: 25%, 4-5: 38%, and 6: 12%). The frequency of symptomatic intracranial hemorrhage was lower for the MRI standard group (6.9%) than for the CT standard group (18.8%). However, there was no statistical difference in the prognosis and incidence of intracranial hemorrhage between the 2 groups, due to the small number of cases. When selecting patients for intravenous rt-PA, brain infarction improved more, prognosis was better three months later, and the frequency of symptomatic intracranial hemorrhage was lower among patients selected based on MRI standards than among those selected based on CT standards. (author)

  10. The effects of ageing on mouse muscle microstructure: a comparative study of time-dependent diffusion MRI and histological assessment.

    Science.gov (United States)

    Porcari, Paola; Hall, Matt G; Clark, Chris A; Greally, Elizabeth; Straub, Volker; Blamire, Andrew M

    2018-03-01

    The investigation of age-related changes in muscle microstructure between developmental and healthy adult mice may help us to understand the clinical features of early-onset muscle diseases, such as Duchenne muscular dystrophy. We investigated the evolution of mouse hind-limb muscle microstructure using diffusion imaging of in vivo and in vitro samples from both actively growing and mature mice. Mean apparent diffusion coefficients (ADCs) of the gastrocnemius and tibialis anterior muscles were determined as a function of diffusion time (Δ), age (7.5, 22 and 44 weeks) and diffusion gradient direction, applied parallel or transverse to the principal axis of the muscle fibres. We investigated a wide range of diffusion times with the goal of probing a range of diffusion lengths characteristic of muscle microstructure. We compared the diffusion time-dependent ADC of hind-limb muscles with histology. ADC was found to vary as a function of diffusion time in muscles at all stages of maturation. Muscle water diffusivity was higher in younger (7.5 weeks) than in adult (22 and 44 weeks) mice, whereas no differences were observed between the older ages. In vitro data showed the same diffusivity pattern as in vivo data. The highlighted differences in diffusion properties between young and mature muscles suggested differences in underlying muscle microstructure, which were confirmed by histological assessment. In particular, although diffusion was more restricted in older muscle, muscle fibre size increased significantly from young to adult age. The extracellular space decreased with age by only ~1%. This suggests that the observed diffusivity differences between young and adult muscles may be caused by increased membrane permeability in younger muscle associated with properties of the sarcolemma. Copyright © 2018 John Wiley & Sons, Ltd.

  11. Area-specific modulation of neural activation comparing escitalopram and citalopram revealed by pharmaco-fMRI: a randomized cross-over study.

    Science.gov (United States)

    Windischberger, Christian; Lanzenberger, Rupert; Holik, Alexander; Spindelegger, Christoph; Stein, Patrycja; Moser, Ulrike; Gerstl, Florian; Fink, Martin; Moser, Ewald; Kasper, Siegfried

    2010-01-15

    Area-specific and stimulation-dependent changes of human brain activation by selective serotonin reuptake inhibitors (SSRI) are an important issue for improved understanding of treatment mechanisms, given the frequent prescription of these drugs in depression and anxiety disorders. The aim of this neuroimaging study was to investigate differences in BOLD-signal caused by administration of the SSRIs escitalopram and citalopram using pharmacological functional magnetic resonance imaging (pharmaco-fMRI). Eighteen healthy subjects participated in a placebo-controlled, randomized, double-blind study in cross-over repeated measures design. Each volunteer performed facial emotional discrimination and a sensorimotor control paradigm during three scanning sessions. Citalopram (20 mg/d), escitalopram (10 mg/d) and placebo were administered for 10 days each with a drug-free period of at least 21 days. Significant pharmacological effects on BOLD-signal were found in the amygdala, medial frontal gyrus, parahippocampal, fusiform and middle temporal gyri. Post-hoc t-tests revealed decreased BOLD-signal in the right amygdala and left parahippocampal gyrus in both pharmacological conditions, compared to placebo. Escitalopram, compared to citalopram, induced a decrease of BOLD-signal in the medial frontal gyrus and an increase in the right fusiform and left parahippocampal gyri. Drug effects were concentrated in brain regions with dense serotonergic projections. Both escitalopram and citalopram attenuated BOLD-signal in the amygdala and parahippocampal cortex to emotionally significant stimuli compared to control stimuli. We believe that reduced reactivity in the medial frontal gyrus found for escitalopram compared to citalopram administration might explain the response differences between study drugs as demonstrated in previous clinical trials.

  12. Comparative diagnostic performance of multidetector computed tomography and MRI for characterization of pancreatic cystic lesions

    International Nuclear Information System (INIS)

    Moon, Sung Min; Shin, Sang Soo; Park, Jin Gyoon; Jeong, Yong Yeon

    2015-01-01

    To compare the diagnostic performance of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in characterization of pancreatic cystic lesions. We conducted a retrospective study on 34 patients with histopathologically proven cystic pancreatic lesions who underwent both preoperative MDCT and MRI. CT and MRI were independently evaluated for differentiating mucinous vs. non-mucinous lesions, differentiating aggressive vs. non-aggressive lesion, analyzing morphological features, and evaluating specific leading diagnoses. Sensitivity, specificity, and accuracy were determined. Competency assessment of lesional morphology analysis was performed using the kappa values of the 2 tests. The sensitivity, specificity, and accuracy of MRI for differentiating mucinous vs. non-mucinous lesions were higher than CT (p = 0.03). For differentiating aggressiveness, the sensitivity of MRI was better than CT, but the specificity of CT was better than MRI. In evaluation of morphologic features, MRI showed better performance in characterization of septa and wall. Otherwise, the 2 modalities showed similarly good performance. MRI was better than CT in determining a specific diagnosis (58.8% vs. 47.2%, respectively). CT and MRI are reasonable diagnostic methods for characterization of pancreatic cystic lesions. However, MRI enables more confident assessment than CT in differentiating mucinous vs. non-mucinous lesions and characterization of the septa and wall

  13. Comparative study of resting-state functional MRI and positron emission tomography-CT in the localization of temporal lobe epileptic focus

    International Nuclear Information System (INIS)

    Zhao Chunlei; Chen Ziqian; Wang Zhimin; Qian Gennian; Ni Ping; Tao Chaochao

    2013-01-01

    Objective: To evaluate the efficacy of PET-CT brain imaging and resting-state fMRI in preoperative localization of temporal lobe epileptic (TLE) focus. Methods: PET-CT and resting-state fMRI were performed in 17 patients with refractory TLE, who then underwent surgical treatment. Seventeen healthy volunteers matched with gender and age were recruited as the control group. The resting-state fMRI images were post processed by SPM5 software. Regional homogeneity (ReHo) values of the whole brain and bilateral hippocampus were obtained and analyzed. PET-CT images were analyzed by visual analysis method and asymmetry index method and the standardized uptake value (SUV) of bilateral hippocampus were obtained. The ReHo values and SUV of the bilateral hippocampus were compared by two independent samples t-test, and analyzed by receiver operating characteristic curve (ROC) for optimized diagnostic threshold. Pearson correlation analysis was employed for evaluating the correlation between the SUV and ReHo values of bilateral hippocampus. The consistency between the diagnostic accuracy of PET-CT and resting-state fMRI was assessed by Kappa consistency test. The outcome of the patient group was compared with that of the control group, and with the pathological results, to evaluate the diagnostic value of the two modalities for preoperative localization of temporal lobe epileptic focus. Results: Regional or comprehensive low metabolism of "1"8F-FDG in temporal lobes was presented in all 17 patients, and 11 patients out of 17 showed lateral decreased ReHo value. The diagnostic accuracy of the two examinations was 70.6% (12/17) and 64.7% (11/17) for PET-CT and resting-state fMRI respectively compared with pathological results, and could be increased to 76.5% (13/17) when the two methods were combined for diagnosis. The ReHo values of the TLE group (0.34 ± 0.12) were significantly lower than those of the control group (0.46 ± 0.07) (t = 3.230, P = 0.003). The sensitivity and

  14. Specific cerebral activation due to visual erotic stimuli in male-to-female transsexuals compared with male and female controls: an fMRI study.

    Science.gov (United States)

    Gizewski, Elke R; Krause, Eva; Schlamann, Marc; Happich, Friederike; Ladd, Mark E; Forsting, Michael; Senf, Wolfgang

    2009-02-01

    Transsexuals harbor the strong feeling of having been born to the wrong sex. There is a continuing controversial discussion of whether or not transsexualism has a biological representation. Differences between males and females in terms of functional imaging during erotic stimuli have been previously described, revealing gender-specific results. Therefore, we postulated that male-to-female (MTF) transsexuals may show specific cerebral activation differing from their biological gender. Cerebral activation patterns during viewing of erotic film excerpts in functional magnetic resonance imaging (fMRI). Twelve male and 12 female heterosexual volunteers and 12 MTF transsexuals before any treatment viewed erotic film excerpts during fMRI. Additionally, subjective rating of sexual arousal was assessed. Statistics were performed using the Statistical Parametric Mapping software. Significantly enhanced activation for men compared with women was revealed in brain areas involved in erotic processing, i.e., the thalamus, the amygdala, and the orbitofrontal and insular cortex, whereas no specific activation for women was found. When comparing MTF transsexuals with male volunteers, activation patterns similar to female volunteers being compared with male volunteers were revealed. Sexual arousal was assessed using standard rating scales and did not differ significantly for the three groups. We revealed a cerebral activation pattern in MTF transsexuals compared with male controls similar to female controls compared with male controls during viewing of erotic stimuli, indicating a tendency of female-like cerebral processing in transsexualism.

  15. Imaging children suffering from lymphoma: an evaluation of different 18F-FDG PET/MRI protocols compared to whole-body DW-MRI.

    Science.gov (United States)

    Kirchner, Julian; Deuschl, Cornelius; Schweiger, Bernd; Herrmann, Ken; Forsting, Michael; Buchbender, Christian; Antoch, Gerald; Umutlu, Lale

    2017-09-01

    The objectives of this study were to evaluate and compare the diagnostic potential of different PET/MRI reading protocols, entailing non-enhanced / contrast-enhanced and diffusion-weighted 18 F-FDG PET/MR imaging and whole-body diffusion-weighted MRI for lesion detection and determination of the tumor stage in pediatric lymphoma patients. A total of 28 18 F-FDG PET/MRI datasets were included for analysis of four different reading protocols: (1) PET/MRI utilizing sole unenhanced T2w and T1w imaging, (2) PET/MRI utilizing additional contrast enhanced sequences, (3) PET/MR imaging utilizing unenhanced, contrast enhanced and DW imaging or (4) WB-DW-MRI. Statistical analyses were performed on a per-patient and a per-lesion basis. Follow-up and prior examinations as well as histopathology served as reference standards. PET/MRI correctly identified all 17 examinations with active lymphoma disease, while WB-DW-MRI correctly identified 15/17 examinations. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were 96%, 96.5%, 97%, 95%, and 96% for PET/MRI 1 ; 97%, 96.5%, 97%, 96.5%, and 97% for PET/MRI 2 ; 97%, 96.5%, 97%, 96.5%, and 97% for PET/MRI 3 and 77%, 96%, 96%, 78.5% and 86% for MRI-DWI. 18 F-FDG PET/MRI is superior to WB-DW-MRI in staging pediatric lymphoma patients. Neither application of contrast media nor DWI leads to a noticeable improvement of the diagnostic accuracy of PET/MRI. Thus, unenhanced PET/MRI may play a crucial role for the diagnostic work-up of pediatric lymphoma patients in the future.

  16. Imaging children suffering from lymphoma: an evaluation of different {sup 18}F-FDG PET/MRI protocols compared to whole-body DW-MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kirchner, Julian; Buchbender, Christian; Antoch, Gerald [University Dusseldorf, Department of Diagnostic and Interventional Radiology, Medical Faculty, Dusseldorf (Germany); Deuschl, Cornelius; Schweiger, Bernd; Forsting, Michael; Umutlu, Lale [University Hospital Essen, University of Duisburg-Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Herrmann, Ken [University Hospital Essen, University of Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany)

    2017-09-15

    The objectives of this study were to evaluate and compare the diagnostic potential of different PET/MRI reading protocols, entailing non-enhanced / contrast-enhanced and diffusion-weighted {sup 18}F-FDG PET/MR imaging and whole-body diffusion-weighted MRI for lesion detection and determination of the tumor stage in pediatric lymphoma patients. A total of 28 {sup 18}F-FDG PET/MRI datasets were included for analysis of four different reading protocols: (1) PET/MRI utilizing sole unenhanced T2w and T1w imaging, (2) PET/MRI utilizing additional contrast enhanced sequences, (3) PET/MR imaging utilizing unenhanced, contrast enhanced and DW imaging or (4) WB-DW-MRI. Statistical analyses were performed on a per-patient and a per-lesion basis. Follow-up and prior examinations as well as histopathology served as reference standards. PET/MRI correctly identified all 17 examinations with active lymphoma disease, while WB-DW-MRI correctly identified 15/17 examinations. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were 96%, 96.5%, 97%, 95%, and 96% for PET/MRI{sub 1}; 97%, 96.5%, 97%, 96.5%, and 97% for PET/MRI{sub 2}; 97%, 96.5%, 97%, 96.5%, and 97% for PET/MRI{sub 3} and 77%, 96%, 96%, 78.5% and 86% for MRI-DWI. {sup 18}F-FDG PET/MRI is superior to WB-DW-MRI in staging pediatric lymphoma patients. Neither application of contrast media nor DWI leads to a noticeable improvement of the diagnostic accuracy of PET/MRI. Thus, unenhanced PET/MRI may play a crucial role for the diagnostic work-up of pediatric lymphoma patients in the future. (orig.)

  17. A Pilot Comparative Study of Quantitative Ultrasound, Conventional Ultrasound, and MRI for Predicting Histology-Determined Steatosis Grade in Adult Nonalcoholic Fatty Liver Disease.

    Science.gov (United States)

    Paige, Jeremy S; Bernstein, Gregory S; Heba, Elhamy; Costa, Eduardo A C; Fereirra, Marilia; Wolfson, Tanya; Gamst, Anthony C; Valasek, Mark A; Lin, Grace Y; Han, Aiguo; Erdman, John W; O'Brien, William D; Andre, Michael P; Loomba, Rohit; Sirlin, Claude B

    2017-05-01

    The purpose of this study is to explore the diagnostic performance of two investigational quantitative ultrasound (QUS) parameters, attenuation coefficient and backscatter coefficient, in comparison with conventional ultrasound (CUS) and MRI-estimated proton density fat fraction (PDFF) for predicting histology-confirmed steatosis grade in adults with nonalcoholic fatty liver disease (NAFLD). In this prospectively designed pilot study, 61 adults with histology-confirmed NAFLD were enrolled from September 2012 to February 2014. Subjects underwent QUS, CUS, and MRI examinations within 100 days of clinical-care liver biopsy. QUS parameters (attenuation coefficient and backscatter coefficient) were estimated using a reference phantom technique by two analysts independently. Three-point ordinal CUS scores intended to predict steatosis grade (1, 2, or 3) were generated independently by two radiologists on the basis of QUS features. PDFF was estimated using an advanced chemical shift-based MRI technique. Using histologic examination as the reference standard, ROC analysis was performed. Optimal attenuation coefficient, backscatter coefficient, and PDFF cutoff thresholds were identified, and the accuracy of attenuation coefficient, backscatter coefficient, PDFF, and CUS to predict steatosis grade was determined. Interobserver agreement for attenuation coefficient, backscatter coefficient, and CUS was analyzed. CUS had 51.7% grading accuracy. The raw and cross-validated steatosis grading accuracies were 61.7% and 55.0%, respectively, for attenuation coefficient, 68.3% and 68.3% for backscatter coefficient, and 76.7% and 71.3% for MRI-estimated PDFF. Interobserver agreements were 53.3% for CUS (κ = 0.61), 90.0% for attenuation coefficient (κ = 0.87), and 71.7% for backscatter coefficient (κ = 0.82) (p hepatic steatosis grade in patients with NAFLD.

  18. The effects of breathing motion on DCE-MRI images: Phantom studies simulating respiratory motion to compare CAIPARINHA-VIBE, radial VIBE, and conventional VIBE

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Kyung; Seo, Nieun; Kim, Bohyun; Huh, Jimi; Kim, Jeong Kon; Lee, Seung Soo; KIm, Kyung Won [Dept. of Radiology, and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Kim, In Seong [Siemens Healthcare Korea, Seoul (Korea, Republic of); Nickel, Dominik [MR Application Predevelopment, Siemens Healthcare, Erlangen (Germany)

    2017-04-15

    To compare the breathing effects on dynamic contrast-enhanced (DCE)-MRI between controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA)-volumetric interpolated breath-hold examination (VIBE), radial VIBE with k-space-weighted image contrast view-sharing (radial-VIBE), and conventional VIBE (c-VIBE) sequences using a dedicated phantom experiment. We developed a moving platform to simulate breathing motion. We conducted dynamic scanning on a 3T machine (MAGNETOM Skyra, Siemens Healthcare) using CAIPIRINHA-VIBE, radial-VIBE, and c-VIBE for six minutes per sequence. We acquired MRI images of the phantom in both static and moving modes, and we also obtained motion-corrected images for the motion mode. We compared the signal stability and signal-to-noise ratio (SNR) of each sequence according to motion state and used the coefficients of variation (CoV) to determine the degree of signal stability. With motion, CAIPIRINHA-VIBE showed the best image quality, and the motion correction aligned the images very well. The CoV (%) of CAIPIRINHA-VIBE in the moving mode (18.65) decreased significantly after the motion correction (2.56) (p < 0.001). In contrast, c-VIBE showed severe breathing motion artifacts that did not improve after motion correction. For radial-VIBE, the position of the phantom in the images did not change during motion, but streak artifacts significantly degraded image quality, also after motion correction. In addition, SNR increased in both CAIPIRINHA-VIBE (from 3.37 to 9.41, p < 0.001) and radial-VIBE (from 4.3 to 4.96, p < 0.001) after motion correction. CAIPIRINHA-VIBE performed best for free-breathing DCE-MRI after motion correction, with excellent image quality.

  19. Brain MRI and single photon emission computed tomography in severe athetotic cerebral palsy. A comparative study with mental and motor disorders

    International Nuclear Information System (INIS)

    Yamada, Kazutaka; Tsuzura, Shigenobu; Matsuda, Hiroshi.

    1995-01-01

    Single photon emission computed tomography (SPECT) using N-isopropyl-p-[ 123 I]-iodoamphetamine ( 123 I-IMP) was performed in twelve patients with severe athetotic cerebral palsy (Ath; 5 males and 7 females) who had both motor delay (unable to move) and mental retardation (I.Q, or D.Q, below 30). The neuroimaging findings of those patients were compared with those of patients mental and motor disorders. In five caes suffering from neonatal asphyxia, SPECT demonstrated a decreased regional cerebral blood flow (rCBF) in corpus striatum, thalamus, orbitofrontal areas, pericentral gyrus areas, prefrontal areas and medial temporal areas. In seven cases suffering from neonatal jaundice, SPECT demonstrated a decreased rCBF in orbito-frontal areas, prefrontal areas and medial temporal areas. SPECT showed hypoperfusion of peri-central gyrus areas in cases with complications of spastic palsy. The decreased rCBF in medial temporal areas mostly corresponded to an alteration in hippocampal formation as assessed by magnetic resonance imaging (MRI). Cases with hypoperfusion of bilateral medial temporal areas showed a lower score of language understanding than those with the unilateral damage. In cases with hypofusion of bilateral prefrontal areas and bilateral medial temporal areas, the grade of understanding of language was almost below 12 months. In cases with hypoperfusion of orbitofrontal areas, psychomotor hypersensitivity had been observed. Those results suggest that IMP-SPECT and MRI of the brain is useful tool for neurological assessment in handicapped patients with athetotic cerebral palsy. (author)

  20. Brain MRI and single photon emission computed tomography in severe athetotic cerebral palsy. A comparative study with mental and motor disorders

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Kazutaka; Tsuzura, Shigenobu [Metropolitan Medical Center of the Severely Handicapped, Fuchu, Tokyo (Japan); Matsuda, Hiroshi

    1995-07-01

    Single photon emission computed tomography (SPECT) using N-isopropyl-p-[{sup 123}I]-iodoamphetamine ({sup 123}I-IMP) was performed in twelve patients with severe athetotic cerebral palsy (Ath; 5 males and 7 females) who had both motor delay (unable to move) and mental retardation (I.Q, or D.Q, below 30). The neuroimaging findings of those patients were compared with those of patients mental and motor disorders. In five caes suffering from neonatal asphyxia, SPECT demonstrated a decreased regional cerebral blood flow (rCBF) in corpus striatum, thalamus, orbitofrontal areas, pericentral gyrus areas, prefrontal areas and medial temporal areas. In seven cases suffering from neonatal jaundice, SPECT demonstrated a decreased rCBF in orbito-frontal areas, prefrontal areas and medial temporal areas. SPECT showed hypoperfusion of peri-central gyrus areas in cases with complications of spastic palsy. The decreased rCBF in medial temporal areas mostly corresponded to an alteration in hippocampal formation as assessed by magnetic resonance imaging (MRI). Cases with hypoperfusion of bilateral medial temporal areas showed a lower score of language understanding than those with the unilateral damage. In cases with hypofusion of bilateral prefrontal areas and bilateral medial temporal areas, the grade of understanding of language was almost below 12 months. In cases with hypoperfusion of orbitofrontal areas, psychomotor hypersensitivity had been observed. Those results suggest that IMP-SPECT and MRI of the brain is useful tool for neurological assessment in handicapped patients with athetotic cerebral palsy. (author).

  1. Degeneration and height of cervical discs classified from MRI compared with precise height measurements from radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Kolstad, Frode [National Centre of Spinal Disorders, Norwegian University of Science and Technology, University Hospital of Trondheim, 7006 Trondheim (Norway)]. E-mail: frode.kolstad@medisin.ntnu.no; Myhr, Gunnar [Department of Radiology, University Hospital of Trondheim, 7006 Trondheim (Norway); Kvistad, Kjell Arne [Department of Radiology, University Hospital of Trondheim, 7006 Trondheim (Norway); Nygaard, Oystein P. [National Centre of Spinal Disorders, Norwegian University of Science and Technology, University Hospital of Trondheim, 7006 Trondheim (Norway); Leivseth, Gunnar [Department of Neuromedicine, Faculty of Medicine, Norwegian University of Science and Technology, University Hospital of Trondheim, 7006 Trondheim (Norway)

    2005-09-01

    Study design: Descriptive study comparing MRI classifications with measurements from radiographs. Objectives: 1.Define the relationship between MRI classified cervical disc degeneration and objectively measured disc height. 2.Assess the level of inter- and intra-observer errors using MRI in defining cervical disc degeneration. Summary of background data: Cervical spine degeneration has been defined radiologically by loss of disc height, decreased disc and bone marrow signal intensity and disc protrusion/herniation on MRI. The intra- and inter-observer error using MRI in defining cervical degeneration influences data interpretation. Few previous studies have addressed this source of error. The relation and time sequence between cervical disc degeneration classified by MRI and cervical disc height decrease measured from radiographs is unclear. Methods: The MRI classification of degeneration was based on nucleus signal, prolaps identification and bone marrow signal. Two neuro-radiologists evaluated the MR-images independently in a blinded fashion. The radiographic disc height measurements were done by a new computer-assisted method compensating for image distortion and permitting comparison with normal level-, age- and gender-appropriate disc height. Results/conclusions: 1.Progressing disc degeneration classified from MRI is on average significantly associated with a decrease of disc height as measured from radiographs. Within each MRI defined category of degeneration measured disc heights, however, scatter in a wide range. 2.The inter-observer agreement between two neuro-radiologists in both defining degeneration and disc height by MRI was only moderate. Studies addressing questions related to cervical disc degeneration should take this into consideration.

  2. Degeneration and height of cervical discs classified from MRI compared with precise height measurements from radiographs

    International Nuclear Information System (INIS)

    Kolstad, Frode; Myhr, Gunnar; Kvistad, Kjell Arne; Nygaard, Oystein P.; Leivseth, Gunnar

    2005-01-01

    Study design: Descriptive study comparing MRI classifications with measurements from radiographs. Objectives: 1.Define the relationship between MRI classified cervical disc degeneration and objectively measured disc height. 2.Assess the level of inter- and intra-observer errors using MRI in defining cervical disc degeneration. Summary of background data: Cervical spine degeneration has been defined radiologically by loss of disc height, decreased disc and bone marrow signal intensity and disc protrusion/herniation on MRI. The intra- and inter-observer error using MRI in defining cervical degeneration influences data interpretation. Few previous studies have addressed this source of error. The relation and time sequence between cervical disc degeneration classified by MRI and cervical disc height decrease measured from radiographs is unclear. Methods: The MRI classification of degeneration was based on nucleus signal, prolaps identification and bone marrow signal. Two neuro-radiologists evaluated the MR-images independently in a blinded fashion. The radiographic disc height measurements were done by a new computer-assisted method compensating for image distortion and permitting comparison with normal level-, age- and gender-appropriate disc height. Results/conclusions: 1.Progressing disc degeneration classified from MRI is on average significantly associated with a decrease of disc height as measured from radiographs. Within each MRI defined category of degeneration measured disc heights, however, scatter in a wide range. 2.The inter-observer agreement between two neuro-radiologists in both defining degeneration and disc height by MRI was only moderate. Studies addressing questions related to cervical disc degeneration should take this into consideration

  3. 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.

  4. 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.

  5. Evidence of a modality-dependent role of the cerebellum in working memory? An fMRI study comparing verbal and abstract n-back tasks.

    Science.gov (United States)

    Hautzel, Hubertus; Mottaghy, Felix M; Specht, Karsten; Müller, Hans-Wilhelm; Krause, Bernd J

    2009-10-01

    In working memory (WM), functional imaging studies demonstrate cerebellar involvement indicating a cognitive role of the cerebellum. These cognitive contributions were predominantly interpreted as part of the phonological loop within the Baddeley model of WM. However, those underlying investigations were performed in the context of visual verbal WM which could pose a bias when interpreting the results. The aim of this fMRI study was to address the question of whether the cerebellum supports additional aspects of WM in the context of higher cognitive functions. Furthermore, laterality effects were investigated to further disentangle the cerebellar role in the context of the phonological loop and the visuospatial sketchpad. A direct comparison of verbal and abstract visual WM was performed in 17 young volunteers by applying a 2-back paradigm and extracting the % change in BOLD signal from the fMRI data. To minimize potential verbal strategies, Attneave and Arnoult shapes of non-nameable objects were chosen for the abstract condition. The analyses revealed no significant differences in verbal vs. abstract WM. Moreover, no laterality effects were demonstrated in both verbal and abstract WM. These results provide further evidence of a broader cognitive involvement of the cerebellum in WM that is not only confined to the phonological loop but also supports central executive subfunctions. The fact that no lateralization effects are found might be attributed to the characteristics of the n-back paradigm which emphasizes central executive subfunctions over the subsidiary slave systems.

  6. 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 ...

  7. Right ventricular volume estimation with cine MRI; A comparative study between Simpson's rule and a new modified area-length method

    Energy Technology Data Exchange (ETDEWEB)

    Sawachika, Takashi (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1993-04-01

    To quantitate right ventricular (RV) volumes easily using cine MRI, we developed a new method called 'modified area-length method (MOAL method)'. To validate this method, we compared it to the conventional Simpson's rule. Magnetom H15 (Siemens) was used and 6 normal volunteers and 21 patients with various RV sizes were imaged with ECG triggered gradient echo method (FISP, TR 50 ms, TE 12 ms, slice thickness 9 mm). For Simpson's rule transverse images of 12 sequential views which cover whole heart were acquired. For the MOAL method, two orthogonal views were imaged. One was the sagittal view which includes RV outflow tract and the other was the coronal view defined from the sagittal image to cover the whole RV. From these images the area (As, Ac) of RV and the longest distance between RV apex and pulmonary valve (Lmax) were determined. By correlating RV volumes measured by Simpson's rule to As*Ac/Lmax the RV volume could be estimated as follows: V=0.85*As*Ac/Lmax+4.55. Thus the MOAL method demonstrated excellent accuracy to quantitate RV volume and the acquisition time abbreviated to one fifth compared with Simpson's rule. This should be a highly promising method for routine clinical application. (author).

  8. Comparative Lateralizing Ability of Multimodality MRI in Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Karabekir Ercan

    2016-01-01

    Full Text Available Purpose. The objective is to compare lateralizing ability of three quantitative MR (qMRI modalities to depict changes of hippocampal architecture with clinical entities in temporal lobe epilepsy. Methods. We evaluated 14 patients with clinical and EEG proven diagnosis of unilateral TLE and 15 healthy volunteers. T1-weighted 3D dataset for volumetry, single-voxel 1H MR spectroscopy (MRS, and diffusion tensor imaging (DTI were performed for bilateral hippocampi of all subjects. Results. Individual volumetric measurements provided accurate lateralization in 85% of the patients, spectroscopy in 57%, and DTI in 57%. Higher lateralization ratios were acquired combining volumetry-spectroscopy (85%, spectroscopy-DTI (85%, and volumetry-DTI (100%. Significantly decreased NAA/(Cho+Cr ratios (p=0.002 and increased FA (p=0.001 values were obtained in ipsilateral to epileptogenic hippocampus. Duration of epilepsy and FA values showed a significant negative correlation (p=0.016, r=-0.847. The history of febrile convulsion associated with ipsilateral increased ADC values (p=0.015, r=0.851 and reduced NAA/(Cho+Cr ratios (p=0.047, r=-761. Conclusion. Volumetry, MRS, and DTI studies provide complementary information of hippocampal pathology. For lateralization of epileptogenic focus and preoperative examination, volumetry-DTI combination may be indicative of diagnostic accuracy.

  9. Comparing brain white matter on sequential cranial ultrasound and MRI in very preterm infants

    Energy Technology Data Exchange (ETDEWEB)

    Leijser, Lara M.; Veen, Sylvia; Boer, Inge P. de; Walther, Frans J.; Wezel-Meijler, Gerda van [Leiden University Medical Center, Department of Pediatrics, Division of Neonatology, Albinusdreef 2, P.O. Box 9600, Leiden (Netherlands); Liauw, Lishya [Leiden University Medical Center, Department of Radiology, Division of Neuroradiology, Albinusdreef 2, P.O. Box 9600, Leiden (Netherlands)

    2008-09-15

    Periventricular white matter (WM) echodensities, frequently seen in preterm infants, can be associated with suboptimal neurodevelopment. Major WM injury is well detected on cranial ultrasound (cUS). cUS seems less sensitive for diffuse or more subtle WM injury. Our aim was to assess the value of cUS and magnetic resonance imaging (MRI) for evaluating WM changes and the predictive value of cUS and/or MRI findings for neurodevelopmental outcome in very preterm infants with normal to severely abnormal WM on sequential high-quality cUS. Very preterm infants (<32 weeks) who had sequential cUS and one MRI within the first three postnatal months were included. Periventricular WM on cUS and MRI was compared and correlated with neurodevelopmental outcome at 2 years corrected age. Forty preterm infants were studied; outcome data were available in 32. WM changes on sequential cUS were predictive of WM changes on MRI. Severely abnormal WM on cUS/MRI was predictive of adverse outcome, and normal-mildly abnormal WM of favorable outcome. Moderately abnormal WM on cUS/MRI was associated with variable outcome. Additional MRI slightly increased the predictive value of cUS in severe WM changes. Sequential cUS in preterm infants is reliable for detecting WM changes and predicting favorable and severely abnormal outcome. Conventional and diffusion-weighted MRI sequences before term equivalent age in very preterm infants, suggested on cUS to have mild to moderately abnormal WM, do not seem to be warranted. (orig.)

  10. Comparing brain white matter on sequential cranial ultrasound and MRI in very preterm infants

    International Nuclear Information System (INIS)

    Leijser, Lara M.; Veen, Sylvia; Boer, Inge P. de; Walther, Frans J.; Wezel-Meijler, Gerda van; Liauw, Lishya

    2008-01-01

    Periventricular white matter (WM) echodensities, frequently seen in preterm infants, can be associated with suboptimal neurodevelopment. Major WM injury is well detected on cranial ultrasound (cUS). cUS seems less sensitive for diffuse or more subtle WM injury. Our aim was to assess the value of cUS and magnetic resonance imaging (MRI) for evaluating WM changes and the predictive value of cUS and/or MRI findings for neurodevelopmental outcome in very preterm infants with normal to severely abnormal WM on sequential high-quality cUS. Very preterm infants (<32 weeks) who had sequential cUS and one MRI within the first three postnatal months were included. Periventricular WM on cUS and MRI was compared and correlated with neurodevelopmental outcome at 2 years corrected age. Forty preterm infants were studied; outcome data were available in 32. WM changes on sequential cUS were predictive of WM changes on MRI. Severely abnormal WM on cUS/MRI was predictive of adverse outcome, and normal-mildly abnormal WM of favorable outcome. Moderately abnormal WM on cUS/MRI was associated with variable outcome. Additional MRI slightly increased the predictive value of cUS in severe WM changes. Sequential cUS in preterm infants is reliable for detecting WM changes and predicting favorable and severely abnormal outcome. Conventional and diffusion-weighted MRI sequences before term equivalent age in very preterm infants, suggested on cUS to have mild to moderately abnormal WM, do not seem to be warranted. (orig.)

  11. Comparative study on occurrence characteristics of matrix water in static and gas double-dynamic solid-state fermentations using low-field NMR and MRI.

    Science.gov (United States)

    He, Qin; Chen, Hong-zhang

    2015-12-01

    The water in a solid substrate is generally divided into three forms: hygroscopic, capillary, and free. However, there are few methods available for detecting the contents of different states of water in substrates. In this paper, low-field NMR and MRI were used to analyze the water occurrence characteristics of steam-exploded corn straw in solid-state fermentation (SSF). A significant linear relationship was found between the total NMR peak areas and the total water contents with a correlation coefficient of 0.993. It was further proved to be successful in comparing the contents and distributions of different states of water in static SSF and gas double-dynamic SSF (GDD-SSF). The results showed that among the three states of water, capillary water was the main form of water present and lost in substrates during fermentation. Total water and capillary water contents did not significantly differ as a result of different sample treatments, but hygroscopic water and free water contents in static SSF were respectively 0.38 and 2.98 times that in GDD-SSF with a packing height of 3 cm after fermentation. A relatively uniform water distribution and deep-depth region for microbial growth were found in GDD-SSF, suggesting that GDD-SSF was more suitable for industrialization. This technology has great potential for achieving efficient on-line water supply through water loss detection in SSF.

  12. The diagnosis of breast implant rupture: MRI findings compared with findings at explantation

    International Nuclear Information System (INIS)

    Hoelmich, Lisbet R.; Vejborg, Ilse; Conrad, Carsten; Sletting, Susanne; McLaughlin, Joseph K.

    2005-01-01

    Study objective: The aim of this study was to evaluate the accuracy of Magnetic Resonance Imaging (MRI) as performed according to a strict study protocol in diagnosing rupture of silicone breast implants. Material and methods: The study population consisted of 64 women with 118 implants, who had participated in either one or two study MRI examinations, aiming at determining the prevalence and incidence of silent implant rupture, respectively, and who subsequently underwent explantation. Implant rupture status was determined by four independent readers and a consensus diagnosis of either rupture (intracapsular or extracapsular), possible rupture or intact implant was then obtained. Strict predetermined rupture criteria were applied as described in this report and findings at surgery were abstracted in a standardised manner and results compared. Results: At MRI, 66 implants were diagnosed as ruptured, nine as possibly ruptured and 43 as intact. Among the ruptured implants, 27 were categorized as extracapsular. At surgery, on average 297 days after the MRI, 65 of the 66 rupture diagnoses were confirmed, as were 20 of the cases with extracapsular silicone. Eight of the nine possibly ruptured implants were in fact ruptured at surgery. Thirty-four of the 43 intact implants were described as intact at surgery. When categorising possible ruptures as ruptures, there were one false positive and nine false negative rupture diagnoses at MRI yielding an accuracy of 92%, a sensitivity of 89%, and a specificity of 97%. Correspondingly, the predictive value of a positive MRI examination was 99% and the predictive value of a negative MRI examination was 79%. Conclusions: We conclude that MRI is highly accurate for identification of silicone breast implant rupture, with a high sensitivity and specificity when evaluation of images are based on presence of well-defined rupture criteria

  13. Whole-body MRI in children: Would a 3D STIR sequence alone be sufficient for investigating common paediatric conditions? A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Merlini, Laura, E-mail: laura.merlini@hcuge.ch [Department of Radiology, Unit of Pediatric Radiology, University Hospital Rue Willy-Donzé 6, 1205 Geneva (Switzerland); Carpentier, Marc [Department of Epidemiology, University Hospital, Rue Gabrielle-Perret-Gentil 4, 1205 Geneva Switzerland (Switzerland); Ferrey, Solène; Anooshiravani, Mehrak [Department of Radiology, Unit of Pediatric Radiology, University Hospital Rue Willy-Donzé 6, 1205 Geneva (Switzerland); Poletti, Pierre-Alexandre [Department of Radiology, University Hospital, Rue Gabrielle-Perret-Gentil 4, 1205 Geneva (Switzerland); Hanquinet, Sylviane [Department of Radiology, Unit of Pediatric Radiology, University Hospital Rue Willy-Donzé 6, 1205 Geneva (Switzerland)

    2017-03-15

    Objectives: To test the performance of a single 3D IR T2-Weighted sequence compared to a Whole-body MRI protocol including DWI, T1-Weighted and STIR 3D IR (3S) in a pediatric population. Methods: Two radiologists (15 and 30 years of experience),reviewed WBMRIs: first the STIR alone and 2 weeks later the 3S protocol. The indications were variable. Only positive findings were explicitly reported. A third reader compared the results to gold standard (GS) exams specific for the pathology. Agreement between the two readers, sensitivity and positive predictive value of STIR were calculated. Results: fifty-four WBMRIs were included (16 suspected child abuse, 8 chronic recurrent multifocal osteomyelitis (CRMO), 11 lymphomas, 4 osteosarcomas, 9 neuroblastomas, 6 histiocytosis). The mean age was 6 years 10 months, range: 1 month to 15 years. Agreement between readers was of 0.87 [0.82–0.91] for 3D STIR, and 0.89 [0.83–0.93] for the 3S protocol. For reader 1 sensitivity of 3D STIR was 81.6% and of 3S 81.0%. For reader 2 it was 74.1% for 3D STIR and 74.7% for 3S. For both readers and for both protocols, the positive predictive value (PPV) depended on the type of disease (for example 100% histocytosis and osteosarcomas, >90% for child abuse, >85% CRMO but <70% for lymphoma and neuroblastoma). Conclusions: Sensitivities were not different between the 2 protocols, for each reader and were different between the 2 readers for each protocol.

  14. Whole-body MRI in children: Would a 3D STIR sequence alone be sufficient for investigating common paediatric conditions? A comparative study

    International Nuclear Information System (INIS)

    Merlini, Laura; Carpentier, Marc; Ferrey, Solène; Anooshiravani, Mehrak; Poletti, Pierre-Alexandre; Hanquinet, Sylviane

    2017-01-01

    Objectives: To test the performance of a single 3D IR T2-Weighted sequence compared to a Whole-body MRI protocol including DWI, T1-Weighted and STIR 3D IR (3S) in a pediatric population. Methods: Two radiologists (15 and 30 years of experience),reviewed WBMRIs: first the STIR alone and 2 weeks later the 3S protocol. The indications were variable. Only positive findings were explicitly reported. A third reader compared the results to gold standard (GS) exams specific for the pathology. Agreement between the two readers, sensitivity and positive predictive value of STIR were calculated. Results: fifty-four WBMRIs were included (16 suspected child abuse, 8 chronic recurrent multifocal osteomyelitis (CRMO), 11 lymphomas, 4 osteosarcomas, 9 neuroblastomas, 6 histiocytosis). The mean age was 6 years 10 months, range: 1 month to 15 years. Agreement between readers was of 0.87 [0.82–0.91] for 3D STIR, and 0.89 [0.83–0.93] for the 3S protocol. For reader 1 sensitivity of 3D STIR was 81.6% and of 3S 81.0%. For reader 2 it was 74.1% for 3D STIR and 74.7% for 3S. For both readers and for both protocols, the positive predictive value (PPV) depended on the type of disease (for example 100% histocytosis and osteosarcomas, >90% for child abuse, >85% CRMO but <70% for lymphoma and neuroblastoma). Conclusions: Sensitivities were not different between the 2 protocols, for each reader and were different between the 2 readers for each protocol.

  15. An in vitro comparative study of T2 and T2* mappings of human articular cartilage at 3-Tesla MRI using histology as the standard of reference

    International Nuclear Information System (INIS)

    Kim, Taehee; Park, Sunghoon; Min, Byoung-Hyun; Yoon, Seung-Hyun; Kim, Hakil; Lee, Hyun Young; Kwack, Kyu-Sung

    2014-01-01

    The aim of this study was to evaluate the correlations between T2 value, T2* value, and histological grades of degenerated human articular cartilage. T2 mapping and T2* mapping of nine tibial osteochondral specimens were obtained using a 3-T MRI after total knee arthroplasty. A total of 94 ROIs were analyzed. Histological grades were assessed using the David-Vaudey scale. Spearman's rho correlation analysis and Pearson's correlation analysis were performed. The mean relaxation values in T2 map with different histological grades (0, 1, 2) of the cartilage were 51.9 ± 9.2 ms, 55.8 ± 12.8 ms, and 59.6 ± 10.2 ms, respectively. The mean relaxation values in T2* map with different histological grades (0, 1, 2) of the cartilage were 20.3 ± 10.3 ms, 21.1 ± 12.4 ms, and 15.4 ± 8.5 ms, respectively. Spearman's rho correlation analysis confirmed a positive correlation between T2 value and histological grade (ρ = 0.313, p < 0.05). Pearson's correlation analysis revealed a significant negative correlation between T2 and T2* (r = -0.322, p < 0.05). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, this correlation was not statistically significant in this study (ρ = -0.192, p = 0.129). T2 mapping was correlated with histological degeneration, and it may be a good biomarker for osteoarthritis in human articular cartilage. However, the strength of the correlation was weak (ρ = 0.313). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, the correlation was not statistically significant. Therefore, T2 mapping may be more appropriate for the initial diagnosis of articular cartilage degeneration in the knee joint. Further studies on T2* mapping are needed to confirm its reliability and mechanism in cartilage degeneration. (orig.)

  16. Functional and morphological effects of diazepam and midazolam on tumor vasculature in the 9L gliosarcoma brain tumor model using dynamic susceptibility contrast MRI: a comparative study

    Directory of Open Access Journals (Sweden)

    Yan N

    2017-10-01

    Full Text Available Nuo Yan,1 Yuzhen Zheng,2 Cheng Yang1 1Second Department of Anesthesiology, The Affiliated Hospital to Logistics University of PAP, Tianjin, 2Department of Anesthesiology, Tianjin Huanhu Hospital, Tianjin, China Abstract: Antiangiogenic therapy attenuates tumor growth by reducing vascularization. Diazepam (DZP and midazolam (MZL have antiangiogenic properties in human umbilical vein endothelial cells. Thus, we investigated the antiangiogenic activity of DZP and MZL in the rat 9L gliosarcoma brain tumor model. The effect on tumor vasculature was evaluated using dynamic susceptibility contrast magnetic resonance imaging with gradient-echo (GE and spin-echo (SE to assess perfusion parameters, including cerebral blood volume (CBV, cerebral blood flow (CBF, mean transit time (MTT, and mean vessel diameter. The GE-normalized CBF (nCBF in the tumors of untreated controls was significantly lower than that in normal brain tissue, whereas the CBV and MTT were higher. DZP- and MZL-treated rats had higher CBF and lower CBV and MTT values than did untreated controls. The tumor size decreased significantly to 33.5% in DZP-treated rats (P<0.001 and 22.5% in MZL-treated rats (P<0.01 relative to controls. The SE-normalized CBV was lower in DZP-treated (32.9% and MZL-treated (10.6% rats compared with controls. The mean vessel diameter decreased significantly by 32.5% in DPZ-treated and by 24.9% in MZL-treated rats compared with controls (P<0.01. The GE and SE nCBF values were higher in DZP-treated (49.9% and 40.1%, respectively and MZL-treated (41.2% and 32.1%, respectively rats than in controls. The GE- and SE-normalized MTTs were lower in DZP-treated (48.2% and 59.8%, respectively and MZL-treated (40.5% and 51.2%, respectively rats than in controls. Both DZP and MZL had antiangiogenic effects on tumor perfusion and vasculature; however, the antiangiogenic activity of DZP is more promising than that of MZL. Keywords: diazepam, midazolam, 9L gliosarcoma

  17. 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...

  18. An in vitro comparative study of T2 and T2* mappings of human articular cartilage at 3-Tesla MRI using histology as the standard of reference

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Taehee; Park, Sunghoon [Ajou University School of Medicine, Department of Radiology, Suwon (Korea, Republic of); Ajou University Medical Center, Musculoskeletal Imaging Laboratory, Suwon (Korea, Republic of); Min, Byoung-Hyun [Ajou University School of Medicine, Department of Orthopaedic Surgery, Suwon (Korea, Republic of); Ajou University School of Medicine, Cartilage Regeneration Center, Suwon (Korea, Republic of); Yoon, Seung-Hyun [Ajou University School of Medicine, Cartilage Regeneration Center, Suwon (Korea, Republic of); Kim, Hakil [INHA University, School of Information and Communication Engineering, Incheon (Korea, Republic of); Lee, Hyun Young [Ajou University Medical Center, Regional Clinical Trial Center, Suwon (Korea, Republic of); Yonsei University College of Medicine, Department of Biostatistics, Seoul (Korea, Republic of); Kwack, Kyu-Sung [Ajou University School of Medicine, Department of Radiology, Suwon (Korea, Republic of); Ajou University Medical Center, Musculoskeletal Imaging Laboratory, Suwon (Korea, Republic of); Ajou University School of Medicine, Cartilage Regeneration Center, Suwon (Korea, Republic of)

    2014-07-15

    The aim of this study was to evaluate the correlations between T2 value, T2* value, and histological grades of degenerated human articular cartilage. T2 mapping and T2* mapping of nine tibial osteochondral specimens were obtained using a 3-T MRI after total knee arthroplasty. A total of 94 ROIs were analyzed. Histological grades were assessed using the David-Vaudey scale. Spearman's rho correlation analysis and Pearson's correlation analysis were performed. The mean relaxation values in T2 map with different histological grades (0, 1, 2) of the cartilage were 51.9 ± 9.2 ms, 55.8 ± 12.8 ms, and 59.6 ± 10.2 ms, respectively. The mean relaxation values in T2* map with different histological grades (0, 1, 2) of the cartilage were 20.3 ± 10.3 ms, 21.1 ± 12.4 ms, and 15.4 ± 8.5 ms, respectively. Spearman's rho correlation analysis confirmed a positive correlation between T2 value and histological grade (ρ = 0.313, p < 0.05). Pearson's correlation analysis revealed a significant negative correlation between T2 and T2* (r = -0.322, p < 0.05). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, this correlation was not statistically significant in this study (ρ = -0.192, p = 0.129). T2 mapping was correlated with histological degeneration, and it may be a good biomarker for osteoarthritis in human articular cartilage. However, the strength of the correlation was weak (ρ = 0.313). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, the correlation was not statistically significant. Therefore, T2 mapping may be more appropriate for the initial diagnosis of articular cartilage degeneration in the knee joint. Further studies on T2* mapping are needed to confirm its reliability and mechanism in cartilage degeneration. (orig.)

  19. Visual grading of 2D and 3D functional MRI compared with image-based descriptive measures

    Energy Technology Data Exchange (ETDEWEB)

    Ragnehed, Mattias [Linkoeping University, Division of Radiological Sciences, Radiology, IMH, Linkoeping (Sweden); Linkoeping University, Center for Medical Image Science and Visualization, CMIV, Linkoeping (Sweden); Linkoeping University, Department of Medical and Health Sciences, Division of Radiological Sciences/Radiology, Faculty of Health Sciences, Linkoeping (Sweden); Leinhard, Olof Dahlqvist; Pihlsgaard, Johan; Lundberg, Peter [Linkoeping University, Center for Medical Image Science and Visualization, CMIV, Linkoeping (Sweden); Linkoeping University, Division of Radiological Sciences, Radiation Physics, IMH, Linkoeping (Sweden); Wirell, Staffan [Linkoeping University, Division of Radiological Sciences, Radiology, IMH, Linkoeping (Sweden); Linkoeping University Hospital, Department of Radiology, Linkoeping (Sweden); Soekjer, Hannibal; Faegerstam, Patrik [Linkoeping University Hospital, Department of Radiology, Linkoeping (Sweden); Jiang, Bo [Linkoeping University, Center for Medical Image Science and Visualization, CMIV, Linkoeping (Sweden); Smedby, Oerjan; Engstroem, Maria [Linkoeping University, Division of Radiological Sciences, Radiology, IMH, Linkoeping (Sweden); Linkoeping University, Center for Medical Image Science and Visualization, CMIV, Linkoeping (Sweden)

    2010-03-15

    A prerequisite for successful clinical use of functional magnetic resonance imaging (fMRI) is the selection of an appropriate imaging sequence. The aim of this study was to compare 2D and 3D fMRI sequences using different image quality assessment methods. Descriptive image measures, such as activation volume and temporal signal-to-noise ratio (TSNR), were compared with results from visual grading characteristics (VGC) analysis of the fMRI results. Significant differences in activation volume and TSNR were not directly reflected by differences in VGC scores. The results suggest that better performance on descriptive image measures is not always an indicator of improved diagnostic quality of the fMRI results. In addition to descriptive image measures, it is important to include measures of diagnostic quality when comparing different fMRI data acquisition methods. (orig.)

  20. Contrast-enhanced MRI compared with the physical examination in the evaluation of disease activity in juvenile idiopathic arthritis

    International Nuclear Information System (INIS)

    Hemke, Robert; Maas, Mario; Veenendaal, Mira van; Kuijpers, Taco W.; Dolman, Koert M.; Rossum, Marion A.J. van; Berg, J.M. van den

    2014-01-01

    To assess the value of magnetic resonance imaging (MRI) in discriminating between active and inactive juvenile idiopathic arthritis (JIA) patients and to compare physical examination outcomes with MRI outcomes in the assessment of disease status in JIA patients. Consecutive JIA patients with knee involvement were prospectively studied using an open-bore MRI. Imaging findings from 146 JIA patients were analysed (59.6 % female; mean age, 12.9 years). Patients were classified as clinically active or inactive. MRI features were evaluated using the JAMRIS system, comprising validated scores for synovial hypertrophy, bone marrow oedema, cartilage lesions and bone erosions. Inter-reader reliability was good for all MRI features (intra-class correlation coefficient [ICC] = 0.87-0.94). No differences were found between the two groups regarding MRI scores of bone marrow oedema, cartilage lesions or bone erosions. Synovial hypertrophy scores differed significantly between groups (P = 0.016). Nonetheless, synovial hypertrophy was also present in 14 JIA patients (35.9 %) with clinically inactive disease. Of JIA patients considered clinically active, 48.6 % showed no signs of MRI-based synovitis. MRI can discriminate between clinically active and inactive JIA patients. However, physical examination is neither very sensitive nor specific in evaluating JIA disease activity compared with MRI. Subclinical synovitis was present in >35 % of presumed clinically inactive patients. (orig.)

  1. A Prospective Study Comparing 99mTc-Hydroxyethylene-Diphosphonate Planar Bone Scintigraphy and Whole-Body SPECT/CT with 18F-Fluoride PET/CT and 18F-Fluoride PET/MRI for Diagnosing Bone Metastases.

    Science.gov (United States)

    Löfgren, Johan; Mortensen, Jann; Rasmussen, Sine H; Madsen, Claus; Loft, Annika; Hansen, Adam E; Oturai, Peter; Jensen, Karl Erik; Mørk, Mette Louise; Reichkendler, Michala; Højgaard, Liselotte; Fischer, Barbara M

    2017-11-01

    metastases (14%) is likely limited. This conclusion is influenced by the low prevalence of patients with osseous metastases. There may well be significant differences in the sensitivity of SPECT/CT, PET/CT, and PET/MRI compared with pBS, but a larger patient population or a patient population with a higher prevalence of bone metastases would have to be studied to demonstrate this. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

  2. Structural linear measurements in the newborn brain: accuracy of cranial ultrasound compared to MRI

    International Nuclear Information System (INIS)

    Leijser, Lara M.; Srinivasan, Latha; Cowan, Frances M.; Rutherford, Mary A.; Counsell, Serena J.; Allsop, Joanna M.

    2007-01-01

    Structural size in the neonatal brain is of clinical importance. Cranial ultrasonography (cUS) is the primary method used for evaluating the neonatal brain and it is important to know whether linear measurements made using this technique are accurate. To compare linear measurements of different cerebral structures made from neonatal cUS and contemporaneous MRI. Preterm and term infants studies with cUS and MRI on the same day were studied. Linear measurements made using both techniques from many cerebral structures were compared using a paired t-test. A total of 44 sets of scans from 26 preterm and 8 term infants were assessed. Small but significant differences between the cUS and MRI measurements (P<0.05) were found for the ventricular index, the posterior horn depth of the lateral ventricle, the extracerebral space and interhemispheric fissure, and the cortex of the cingulate gyrus. No significant differences were found for any other measurements. Linear measurements from cUS are accurate for most neonatal cerebral structures. Significant differences compared to MRI were found for a few structures, but only for the cortex were the absolute differences marked and possibly of clinical importance. (orig.)

  3. MRI with intraoral orthodontic appliance-a comparative in vitro and in vivo study of image artefacts at 1.5 T.

    Science.gov (United States)

    Zachriat, C; Asbach, P; Blankenstein, K I; Peroz, I; Blankenstein, F H

    2015-01-01

    We investigated artefacts caused from orthodontic appliances at 1.5-T MRI of the head and neck region and whether the image quality can be improved utilizing the artefact-minimizing sequence WARP. In vitro tests were performed by phantom measurements of different orthodontic devices applying different types of MR sequences [echoplanar imaging (EPI), turbo spin echo (TSE) and TSE-WARP, gradient echo (GRE)]. Two independent readers determined after calibration the level of artefacts. Subsequently, the interobserver agreement was calculated. The measurement of artefacts was based on the American Society for Testing Materials Standard F 2119-07. For in vivo imaging, one test person was scanned with an inserted multibracket appliance. The level of artefacts for 27 target regions was evaluated. In vitro: ceramic brackets and ferromagnetic steel brackets produced artefact radii up to 1.12 and 7.40 cm, respectively. WARP reduced these artefacts by an average of 32.7%. The Bland-Altman-Plot indicated that maximum measurement differences of 3 mm have to be expected with two calibrated observers. In vivo: the EPI sequence for brain imaging was not analysable. The TSE sequence of the brain did not demonstrate artefacts except for the nasal cavity. Conversely, the TSE sequence of the cervical spine revealed severe artefacts in the midface region. The GRE sequence appeared to be more susceptible to artefacts than did the TSE sequence. In vitro measurements allow an estimation of the in vivo artefact size. Orthodontic appliances may often remain intraorally when performing MRI. WARP showed a more significant effect in vitro than in vivo.

  4. MRI with intraoral orthodontic appliance—a comparative in vitro and in vivo study of image artefacts at 1.5 T

    Science.gov (United States)

    Zachriat, C; Asbach, P; Blankenstein, K I; Peroz, I

    2015-01-01

    Objectives: We investigated artefacts caused from orthodontic appliances at 1.5-T MRI of the head and neck region and whether the image quality can be improved utilizing the artefact-minimizing sequence WARP. Methods: In vitro tests were performed by phantom measurements of different orthodontic devices applying different types of MR sequences [echoplanar imaging (EPI), turbo spin echo (TSE) and TSE-WARP, gradient echo (GRE)]. Two independent readers determined after calibration the level of artefacts. Subsequently, the interobserver agreement was calculated. The measurement of artefacts was based on the American Society for Testing Materials Standard F 2119-07. For in vivo imaging, one test person was scanned with an inserted multibracket appliance. The level of artefacts for 27 target regions was evaluated. Results: In vitro: ceramic brackets and ferromagnetic steel brackets produced artefact radii up to 1.12 and 7.40 cm, respectively. WARP reduced these artefacts by an average of 32.7%. The Bland–Altman-Plot indicated that maximum measurement differences of 3 mm have to be expected with two calibrated observers. In vivo: the EPI sequence for brain imaging was not analysable. The TSE sequence of the brain did not demonstrate artefacts except for the nasal cavity. Conversely, the TSE sequence of the cervical spine revealed severe artefacts in the midface region. The GRE sequence appeared to be more susceptible to artefacts than did the TSE sequence. Conclusions: In vitro measurements allow an estimation of the in vivo artefact size. Orthodontic appliances may often remain intraorally when performing MRI. WARP showed a more significant effect in vitro than in vivo. PMID:25734243

  5. Assessment of early treatment response to neoadjuvant chemotherapy in breast cancer using non-mono-exponential diffusion models: a feasibility study comparing the baseline and mid-treatment MRI examinations

    Energy Technology Data Exchange (ETDEWEB)

    Bedair, Reem; Manavaki, Roido; Gill, Andrew B.; Abeyakoon, Oshaani; Gilbert, Fiona J. [University of Cambridge, Department of Radiology, School of Clinical Medicine, Cambridge (United Kingdom); Priest, Andrew N.; Patterson, Andrew J. [Cambridge University Hospitals NHS Foundation Trust, Department of Radiology, Addenbrookes Hospital, Cambridge (United Kingdom); McLean, Mary A. [Cambridge University Hospitals NHS Foundation Trust, Department of Radiology, Addenbrookes Hospital, Cambridge (United Kingdom); University of Cambridge, Li Ka Shing Centre, Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Graves, Martin J. [University of Cambridge, Department of Radiology, School of Clinical Medicine, Cambridge (United Kingdom); Cambridge University Hospitals NHS Foundation Trust, Department of Radiology, Addenbrookes Hospital, Cambridge (United Kingdom); Griffiths, John R. [University of Cambridge, Li Ka Shing Centre, Cancer Research UK Cambridge Institute, Cambridge (United Kingdom)

    2017-07-15

    To assess the feasibility of the mono-exponential, bi-exponential and stretched-exponential models in evaluating response of breast tumours to neoadjuvant chemotherapy (NACT) at 3 T. Thirty-six female patients (median age 53, range 32-75 years) with invasive breast cancer undergoing NACT were enrolled for diffusion-weighted MRI (DW-MRI) prior to the start of treatment. For assessment of early response, changes in parameters were evaluated on mid-treatment MRI in 22 patients. DW-MRI was performed using eight b values (0, 30, 60, 90, 120, 300, 600, 900 s/mm{sup 2}). Apparent diffusion coefficient (ADC), tissue diffusion coefficient (D{sub t}), vascular fraction (Florin), distributed diffusion coefficient (DDC) and alpha (α) parameters were derived. Then t tests compared the baseline and changes in parameters between response groups. Repeatability was assessed at inter- and intraobserver levels. All patients underwent baseline MRI whereas 22 lesions were available at mid-treatment. At pretreatment, mean diffusion coefficients demonstrated significant differences between groups (p < 0.05). At mid-treatment, percentage increase in ADC and DDC showed significant differences between responders (49 % and 43 %) and non-responders (21 % and 32 %) (p = 0.03, p = 0.04). Overall, stretched-exponential parameters showed excellent repeatability. DW-MRI is sensitive to baseline and early treatment changes in breast cancer using non-mono-exponential models, and the stretched-exponential model can potentially monitor such changes. (orig.)

  6. Assessment of early treatment response to neoadjuvant chemotherapy in breast cancer using non-mono-exponential diffusion models: a feasibility study comparing the baseline and mid-treatment MRI examinations

    International Nuclear Information System (INIS)

    Bedair, Reem; Manavaki, Roido; Gill, Andrew B.; Abeyakoon, Oshaani; Gilbert, Fiona J.; Priest, Andrew N.; Patterson, Andrew J.; McLean, Mary A.; Graves, Martin J.; Griffiths, John R.

    2017-01-01

    To assess the feasibility of the mono-exponential, bi-exponential and stretched-exponential models in evaluating response of breast tumours to neoadjuvant chemotherapy (NACT) at 3 T. Thirty-six female patients (median age 53, range 32-75 years) with invasive breast cancer undergoing NACT were enrolled for diffusion-weighted MRI (DW-MRI) prior to the start of treatment. For assessment of early response, changes in parameters were evaluated on mid-treatment MRI in 22 patients. DW-MRI was performed using eight b values (0, 30, 60, 90, 120, 300, 600, 900 s/mm"2). Apparent diffusion coefficient (ADC), tissue diffusion coefficient (D_t), vascular fraction (Florin), distributed diffusion coefficient (DDC) and alpha (α) parameters were derived. Then t tests compared the baseline and changes in parameters between response groups. Repeatability was assessed at inter- and intraobserver levels. All patients underwent baseline MRI whereas 22 lesions were available at mid-treatment. At pretreatment, mean diffusion coefficients demonstrated significant differences between groups (p < 0.05). At mid-treatment, percentage increase in ADC and DDC showed significant differences between responders (49 % and 43 %) and non-responders (21 % and 32 %) (p = 0.03, p = 0.04). Overall, stretched-exponential parameters showed excellent repeatability. DW-MRI is sensitive to baseline and early treatment changes in breast cancer using non-mono-exponential models, and the stretched-exponential model can potentially monitor such changes. (orig.)

  7. Patellar dislocations in children, adolescents and adults: A comparative MRI study of medial patellofemoral ligament injury patterns and trochlear groove anatomy

    International Nuclear Information System (INIS)

    Balcarek, Peter; Walde, Tim Alexander; Frosch, Stephan; Schuettrumpf, Jan P.; Wachowski, Martin M.; Stuermer, Klaus M.; Frosch, Karl-Heinz

    2011-01-01

    Purpose: The first aim was to compare medial patellofemoral ligament injury patterns in children and adolescents after first-time lateral patellar dislocations with the injury patterns in adults. The second aim was to evaluate the trochlear groove anatomy at different developmental stages of the growing knee joint. Materials and methods: Knee magnetic resonance (MR) images were collected from 22 patients after first-time patellar dislocations. The patients were aged 14.2 years (a range of 11-15 years). The injury pattern of the medial patellofemoral ligament was analysed, and trochlear dysplasia was evaluated with regard to sulcus angle, trochlear depth and trochlear asymmetry. The control data consisted of MR images from 21 adult patients who were treated for first-time lateral patellar dislocation. Results: After patellar dislocation, injury to the medial patellofemoral ligament was found in 90.2% of the children and in 100% of the adult patients. Injury patterns of the medial patellofemoral ligament were similar between the study group and the control group with regard to injury at the patellar attachment site (Type I), to the midsubstance (Type II) and to injury at the femoral origin (Type III) (all p > 0.05). Combined lesions (Type IV) were significantly less frequently observed in adults when compared to the study group (p = 0.02). The magnitude of trochlear dysplasia was similar in children, adolescents and adults with regard to all three of the measured parameter-values (all p > 0.05). In addition, the articular cartilage had a significant effect on the distal femur geometry in both paediatrics and adults. Conclusion: First, the data from our study indicated that the paediatric medial patellofemoral ligament injury patterns, as seen on MR images, were similar to those in adults. Second, the trochlear groove anatomy and the magnitude of trochlear dysplasia, respectively, did not differ between adults and paediatrics with patellar instability. Thus

  8. Patellar dislocations in children, adolescents and adults: A comparative MRI study of medial patellofemoral ligament injury patterns and trochlear groove anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Balcarek, Peter, E-mail: peter.balcarek@med.uni-goettingen.de [Department of Trauma Surgery, Plastic and Reconstructive Surgery, University Medicine, 37075 Goettingen (Germany); Walde, Tim Alexander; Frosch, Stephan; Schuettrumpf, Jan P.; Wachowski, Martin M.; Stuermer, Klaus M. [Department of Trauma Surgery, Plastic and Reconstructive Surgery, University Medicine, 37075 Goettingen (Germany); Frosch, Karl-Heinz [Department of Trauma and Reconstructive Surgery, Asklepios Clinic St. Georg, Hamburg (Germany)

    2011-09-15

    Purpose: The first aim was to compare medial patellofemoral ligament injury patterns in children and adolescents after first-time lateral patellar dislocations with the injury patterns in adults. The second aim was to evaluate the trochlear groove anatomy at different developmental stages of the growing knee joint. Materials and methods: Knee magnetic resonance (MR) images were collected from 22 patients after first-time patellar dislocations. The patients were aged 14.2 years (a range of 11-15 years). The injury pattern of the medial patellofemoral ligament was analysed, and trochlear dysplasia was evaluated with regard to sulcus angle, trochlear depth and trochlear asymmetry. The control data consisted of MR images from 21 adult patients who were treated for first-time lateral patellar dislocation. Results: After patellar dislocation, injury to the medial patellofemoral ligament was found in 90.2% of the children and in 100% of the adult patients. Injury patterns of the medial patellofemoral ligament were similar between the study group and the control group with regard to injury at the patellar attachment site (Type I), to the midsubstance (Type II) and to injury at the femoral origin (Type III) (all p > 0.05). Combined lesions (Type IV) were significantly less frequently observed in adults when compared to the study group (p = 0.02). The magnitude of trochlear dysplasia was similar in children, adolescents and adults with regard to all three of the measured parameter-values (all p > 0.05). In addition, the articular cartilage had a significant effect on the distal femur geometry in both paediatrics and adults. Conclusion: First, the data from our study indicated that the paediatric medial patellofemoral ligament injury patterns, as seen on MR images, were similar to those in adults. Second, the trochlear groove anatomy and the magnitude of trochlear dysplasia, respectively, did not differ between adults and paediatrics with patellar instability. Thus

  9. 18FFDG PET in evaluating malignancies compared with CT, MRI and pathology in 58 cases

    International Nuclear Information System (INIS)

    Li, L.

    2000-01-01

    This article discussed the practical application of 18 F-FDG PET imaging techniques to depict, state, or define recurrences for five important malignancies: lung cancer, colorectal and head-and-neck cancer, intracranial malignant glioma and primary or secondary hepatic malignant diseases. And comparisons of 18 F-FDG PET with CT, MRI imaging were addressed specifically. We reviewed our initial experience with 48 malignant and ten non-malignant cases. Among malignant group, 36 cases were confirmed by operation or biopsy, Other ten non-malignant diseases, including brain infarction, post-radiotherapy necrosis or scar and lung abscesses were followed with CT or MRI at least 6 months. All patients received intravenous administration of 18 F-FDG 10-15 mCi, followed by a 40 minutes uptake phase, and subsequent imaged using a Siemens ECAT 931 whole-body scanner with resolution of 4 mm FWHM in the center of the field of view. Filtered back projection reconstruction was used to display attenuated or non-attenuated corrected images. The result of 18 F-FDG PET was retrospectively evaluated to assess the degree of uptake of 18 F-FDG PET in the tumor tissues and compared with CT, MRI and pathology. CT and MRI exam were taken before or after PET study in two weeks. 18 F-FDG PET scans showed a significantly increased FDG metabolism in 47 malignant lesions, The tumor / normal tissue FDG uptake rate were 4.16 ±2.11. In 47 cases with neoplasm, 18 F-FDG PET findings were constant with or further confirmed the CT or MRI diagnosis in 35/47 (74.5%) and 12/47 (253%) cases. Another one small intracranial metastasis ( 18 F-FDG PET imaging in oncology has demonstrated powerful advantage in characterizing tumor lesions, differentiating recurrent disease from treatment effects, staging tumors, evaluating the extent of disease, and monitoring therapy. But 18 F-FDG PET still cant replace CT or MRI in malignance diagnosis. It will be used to approach and hopefully answer the difficult diagnosis

  10. Comparative analysis of nonlinear dimensionality reduction techniques for breast MRI segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Akhbardeh, Alireza; Jacobs, Michael A. [Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 (United States); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 (United States) and Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 (United States)

    2012-04-15

    Purpose: Visualization of anatomical structures using radiological imaging methods is an important tool in medicine to differentiate normal from pathological tissue and can generate large amounts of data for a radiologist to read. Integrating these large data sets is difficult and time-consuming. A new approach uses both supervised and unsupervised advanced machine learning techniques to visualize and segment radiological data. This study describes the application of a novel hybrid scheme, based on combining wavelet transform and nonlinear dimensionality reduction (NLDR) methods, to breast magnetic resonance imaging (MRI) data using three well-established NLDR techniques, namely, ISOMAP, local linear embedding (LLE), and diffusion maps (DfM), to perform a comparative performance analysis. Methods: Twenty-five breast lesion subjects were scanned using a 3T scanner. MRI sequences used were T1-weighted, T2-weighted, diffusion-weighted imaging (DWI), and dynamic contrast-enhanced (DCE) imaging. The hybrid scheme consisted of two steps: preprocessing and postprocessing of the data. The preprocessing step was applied for B{sub 1} inhomogeneity correction, image registration, and wavelet-based image compression to match and denoise the data. In the postprocessing step, MRI parameters were considered data dimensions and the NLDR-based hybrid approach was applied to integrate the MRI parameters into a single image, termed the embedded image. This was achieved by mapping all pixel intensities from the higher dimension to a lower dimensional (embedded) space. For validation, the authors compared the hybrid NLDR with linear methods of principal component analysis (PCA) and multidimensional scaling (MDS) using synthetic data. For the clinical application, the authors used breast MRI data, comparison was performed using the postcontrast DCE MRI image and evaluating the congruence of the segmented lesions. Results: The NLDR-based hybrid approach was able to define and segment

  11. Comparative analysis of nonlinear dimensionality reduction techniques for breast MRI segmentation

    International Nuclear Information System (INIS)

    Akhbardeh, Alireza; Jacobs, Michael A.

    2012-01-01

    Purpose: Visualization of anatomical structures using radiological imaging methods is an important tool in medicine to differentiate normal from pathological tissue and can generate large amounts of data for a radiologist to read. Integrating these large data sets is difficult and time-consuming. A new approach uses both supervised and unsupervised advanced machine learning techniques to visualize and segment radiological data. This study describes the application of a novel hybrid scheme, based on combining wavelet transform and nonlinear dimensionality reduction (NLDR) methods, to breast magnetic resonance imaging (MRI) data using three well-established NLDR techniques, namely, ISOMAP, local linear embedding (LLE), and diffusion maps (DfM), to perform a comparative performance analysis. Methods: Twenty-five breast lesion subjects were scanned using a 3T scanner. MRI sequences used were T1-weighted, T2-weighted, diffusion-weighted imaging (DWI), and dynamic contrast-enhanced (DCE) imaging. The hybrid scheme consisted of two steps: preprocessing and postprocessing of the data. The preprocessing step was applied for B 1 inhomogeneity correction, image registration, and wavelet-based image compression to match and denoise the data. In the postprocessing step, MRI parameters were considered data dimensions and the NLDR-based hybrid approach was applied to integrate the MRI parameters into a single image, termed the embedded image. This was achieved by mapping all pixel intensities from the higher dimension to a lower dimensional (embedded) space. For validation, the authors compared the hybrid NLDR with linear methods of principal component analysis (PCA) and multidimensional scaling (MDS) using synthetic data. For the clinical application, the authors used breast MRI data, comparison was performed using the postcontrast DCE MRI image and evaluating the congruence of the segmented lesions. Results: The NLDR-based hybrid approach was able to define and segment both

  12. 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...

  13. Usefulness of MRI compared with CT for diagnosis of mesenteric lymphoma in a dog

    International Nuclear Information System (INIS)

    Yasuda, D.; Fujita, M.; Yasuda, S.; Taniguchi, A.; Miura, H.; Hasegawa, D.; Orima, H.

    2004-01-01

    We evaluated the usefulness of MRI and compared it with CT for diagnosis of mesenceric lymphoma in a dog. The results in the plain CT. dynamic CT and plain MR (TIWI and t2W1) images suggested that the mass was a large single nodular lesion with abundant blood perfusion. On enhanced MRI(T1WI) , the mass was depicted as a tumor with adhesion to the gut wall, Exploratory laparotomy confirmed the mass was consistent with the findings on enhanced MRI. We think that MRI might be a useful imaging tool for diagnosis of canine mesenteric lymphoma

  14. Usefulness of MRI compared with CT for diagnosis of mesenteric lymphoma in a dog.

    Science.gov (United States)

    Yasuda, Daiji; Fujita, Michio; Yasuda, Shuichi; Taniguchi, Akiko; Miura, Harumi; Hasegawa, Daisuke; Orima, Hiromitsu

    2004-11-01

    We evaluated the usefulness of MRI and compared it with CT for diagnosis of mesenteric lymphoma in a dog. The results in the plain CT, dynamic CT and plain MR (T1WI and T2WI) images suggested that the mass was a large single nodular lesion with abundant blood perfusion. On enhanced MRI(T1WI) , the mass was depicted as a tumor with adhesion to the gut wall. Exploratory laparotomy confirmed the mass was consistent with the findings on enhanced MRI. We think that MRI might be a useful imaging tool for diagnosis of canine mesenteric lymphoma.

  15. Semiquantitative assessment of focal cartilage damage at 3 T MRI: A comparative study of dual echo at steady state (DESS) and intermediate-weighted (IW) fat suppressed fast spin echo sequences

    Energy Technology Data Exchange (ETDEWEB)

    Roemer, Frank W., E-mail: froemer@bu.edu [Quantitative Imaging Center (QIC), Department of Radiology, Boston University Medical Center, Boston, MA (United States); Department of Radiology, Klinikum Augsburg, Augsburg (Germany); Kwoh, C. Kent [Division of Rheumatology and Clinical Immunology, University of Pittsburgh School of Medicine (United States); VA Pittsburgh Healthcare System (United States); Hannon, Michael J. [Division of Rheumatology and Clinical Immunology, University of Pittsburgh School of Medicine (United States); Crema, Michel D. [Quantitative Imaging Center (QIC), Department of Radiology, Boston University Medical Center, Boston, MA (United States); Moore, Carolyn E. [Department of Nutrition and Food Sciences, Texas Woman' s University (United States); Jakicic, John M. [Department of Health and Physical Activity, University of Pittsburgh (United States); Green, Stephanie M. [Division of Rheumatology and Clinical Immunology, University of Pittsburgh School of Medicine (United States); Guermazi, Ali [Quantitative Imaging Center (QIC), Department of Radiology, Boston University Medical Center, Boston, MA (United States)

    2011-11-15

    Purpose: The aim of the study was to compare semiquantitative assessment of focal cartilage damage using the dual echo at steady state (DESS)- and intermediate-weighted (IW) fat suppressed (fs) sequences at 3 T MRI. Methods: Included were 201 subjects aged 35-65 with frequent knee pain. MRI was performed with the same sequence protocol as in the Osteoarthritis Initiative (OAI): sagittal IW fs, triplanar DESS and coronal IW sequences. Cartilage status was scored according to the WORMS system using all five sequences. A total of 243 focal defects were detected. In an additional consensus reading, the lesions were evaluated side-by-side using only the sagittal DESS and IW fs sequences. Lesion conspicuity was graded from 0 to 3, intrachondral signal changes adjacent to the defect were recorded and the sequence that depicted the lesion with larger diameter was noted. Wilcoxon signed-rank tests, controlled for clustering by person, were used to examine differences between the sequences. Results: 37 (17.5%) of the scorable lesions were located in the medial tibio-femoral (TF), 48 (22.7%) in the lateral TF and 126 (59.7%) in the patello-femoral compartment. 82.5% were superficial and 17.5% full-thickness defects. Conspicuity was superior for the IW sequence (p < 0.001). The DESS sequence showed more associated intrachondral signal changes (p < 0.001). In 103 (48.8%) cases, the IW fs sequence depicted the lesions as being larger (p < 0.001). Conclusions: The IW fs sequence detected more and larger focal cartilage defects than the DESS. More intrachondral signal changes were observed with the DESS.

  16. Comparing the effects of tofacitinib, methotrexate and the combination, on bone marrow oedema, synovitis and bone erosion in methotrexate-naive, early active rheumatoid arthritis: results of an exploratory randomised MRI study incorporating semiquantitative and quantitative techniques

    DEFF Research Database (Denmark)

    Conaghan, Philip G.; Ostergaard, Mikkel; Bowes, Michael A.

    2016-01-01

    OBJECTIVES: To explore the effects of tofacitinib-an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA)-with or without methotrexate (MTX), on MRI endpoints in MTX-naive adult patients with early active RA and synovitis in an index wrist or hand. METHODS: In this exploratory......, phase 2, randomised, double-blind, parallel-group study, patients received tofacitinib 10 mg twice daily + MTX, tofacitinib 10 mg twice daily + placebo (tofacitinib monotherapy), or MTX + placebo (MTX monotherapy), for 1 year. MRI endpoints (Outcome Measures in Rheumatology Clinical Trials RA MRI score...... differences in RAMRIS bone marrow oedema (BME) at month 6 were -1.55 (90% CI -2.52 to -0.58) for tofacitinib + MTX and -1.74 (-2.72 to -0.76) for tofacitinib monotherapy (both ptofacitinib + MTX...

  17. Screening for skeletal metastases of the spine and pelvis: gradient echo opposed-phase MRI compared with bone scintigraphy

    International Nuclear Information System (INIS)

    Neumann, K.; Hosten, N.; Venz, S.

    1995-01-01

    Opposed-phase gradient echo (GRE) MRI at 0.5 T was compared with T1-weighted GRE MRI and bone scintigraphy regarding the detection of malignant bone marrow infiltrates of the spine and pelvis. Seventeen control patients and 41 patients with suspected skeletal metastases were studied with plain and gadolinium-enhanced MRI. In the control group only a vertebral haemangioma showed contrast enhancement, while all metastases (confirmed histologically or by follow-up) were enhancing. Opposed-phase surface coil MRI showed a significantly higher contrast-to-noise ratio of 56 metastases than T1-weighted images. In 28 patients body coil opposed-phase MRI detected more metastatic foci of the spine and pelvis than did bone scintigraphy (84 vs 56). No scintigraphically visualised lesion was missed by MRI. In conclusion, body coil gadolinium-enhanced opposed-phase GRE MRI may be applied as a screening method for skeletal metastases of the spine and pelvis at intermediate field strengths. (orig.)

  18. Screening for skeletal metastases of the spine and pelvis: gradient echo opposed-phase MRI compared with bone scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, K. [Zentralinstitut fuer Roentgendiagnostik, Universitaetsklinikum Essen, Gesamthochschule Essen (Germany); Hosten, N. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Venz, S. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

    1995-11-01

    Opposed-phase gradient echo (GRE) MRI at 0.5 T was compared with T1-weighted GRE MRI and bone scintigraphy regarding the detection of malignant bone marrow infiltrates of the spine and pelvis. Seventeen control patients and 41 patients with suspected skeletal metastases were studied with plain and gadolinium-enhanced MRI. In the control group only a vertebral haemangioma showed contrast enhancement, while all metastases (confirmed histologically or by follow-up) were enhancing. Opposed-phase surface coil MRI showed a significantly higher contrast-to-noise ratio of 56 metastases than T1-weighted images. In 28 patients body coil opposed-phase MRI detected more metastatic foci of the spine and pelvis than did bone scintigraphy (84 vs 56). No scintigraphically visualised lesion was missed by MRI. In conclusion, body coil gadolinium-enhanced opposed-phase GRE MRI may be applied as a screening method for skeletal metastases of the spine and pelvis at intermediate field strengths. (orig.)

  19. 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.

  20. Recruitment of Anterior and Posterior Structures in Lexical-Semantic Processing: An fMRI Study Comparing Implicit and Explicit Tasks

    Science.gov (United States)

    Ruff, Ilana; Blumstein, Sheila E.; Myers, Emily B.; Hutchison, Emmette

    2008-01-01

    Previous studies examining explicit semantic processing have consistently shown activation of the left inferior frontal gyrus (IFG). In contrast, implicit semantic processing tasks have shown activation in posterior areas including the superior temporal gyrus (STG) and the middle temporal gyrus (MTG) with less consistent activation in the IFG.…

  1. 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

  2. Comparing the effects of tofacitinib, methotrexate and the combination, on bone marrow oedema, synovitis and bone erosion in methotrexate-naive, early active rheumatoid arthritis: results of an exploratory randomised MRI study incorporating semiquantitative and quantitative techniques.

    Science.gov (United States)

    Conaghan, Philip G; Østergaard, Mikkel; Bowes, Michael A; Wu, Chunying; Fuerst, Thomas; van der Heijde, Désirée; Irazoque-Palazuelos, Fedra; Soto-Raices, Oscar; Hrycaj, Pawel; Xie, Zhiyong; Zhang, Richard; Wyman, Bradley T; Bradley, John D; Soma, Koshika; Wilkinson, Bethanie

    2016-06-01

    To explore the effects of tofacitinib-an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA)-with or without methotrexate (MTX), on MRI endpoints in MTX-naive adult patients with early active RA and synovitis in an index wrist or hand. In this exploratory, phase 2, randomised, double-blind, parallel-group study, patients received tofacitinib 10 mg twice daily + MTX, tofacitinib 10 mg twice daily + placebo (tofacitinib monotherapy), or MTX + placebo (MTX monotherapy), for 1 year. MRI endpoints (Outcome Measures in Rheumatology Clinical Trials RA MRI score (RAMRIS), quantitative RAMRIS (RAMRIQ) and dynamic contrast-enhanced (DCE) MRI) were assessed using a mixed-effect model for repeated measures. Treatment differences with ptofacitinib + MTX and -1.74 (-2.72 to -0.76) for tofacitinib monotherapy (both ptofacitinib + MTX and -0.52 (-1.46 to 0.41) for tofacitinib monotherapy (both p>0.05 vs MTX monotherapy). Treatment differences in RAMRIQ synovitis were statistically significant at month 3, consistent with DCE MRI findings. Less deterioration of RAMRIS and RAMRIQ erosive damage was seen at months 6 and 12 in both tofacitinib groups versus MTX monotherapy. These results provide consistent evidence using three different MRI technologies that tofacitinib treatment leads to early reduction of inflammation and inhibits progression of structural damage. NCT01164579. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  3. 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.

  4. Ⅲ~Ⅴ对脑神经生物塑化薄片断层解剖与MRI对照研究%A comparative study on sectional anatomy of the cranial nerves between MRI and plastination

    Institute of Scientific and Technical Information of China (English)

    张伟国; 张绍祥; 巫北海; 陈金华; 谭立文

    2001-01-01

    目的:对动眼神经、滑车神经、三叉神经进行塑化切片与MRI对照研究,获得正常影像和断层解剖资料。方法:采用生物塑化技术制作脑神经横断位8例、矢状位和冠状位各1例薄层切片,同时采用FLASH-3D序列完成头颅标本及30例正常人脑干MR扫描,以MPR技术完整显示动眼神经和三叉神经的脑池段全程。结果:塑化薄片断层、标本和活体MR扫描,脑神经行程、解剖形态均有良好的对应关系,滑车神经仅在塑化切片上显示。结论:生物塑化薄层切片能够对脑神经进行准确显示,是脑神经影像学研究的重要对比方法。%Objective: To obtain the normal image and sectional anatomical data of the oculomotor nerve, the trochlear nerve and the trigeminal nerve through the comparative study between MRI and plastination.Methods: The plastination slices of the nerves were made in 10 individuals (8 transversal, 1 sagittal and 1 coronal).Meanwhile, thirty volunteers and ten cadaveric specimens containing the brain-stem were scanned with FLASH-3D sequence, the whole intracisternal segment of the the oculomotor nerve and the trigeminal nerve were reconstructed with MPR.Results: Sectional plastination and MRI images of the nerves revealed the similar result, but the trochlear nerve was only defined on the plastination section. Conclusion: Plastination can demonstrate the cranial nerves accurately, so it is an important comparative studying method of the cranial nerves.

  5. Confidence in Assessment of Lumbar Spondylolysis Using Three-Dimensional Volumetric T2-Weighted MRI Compared With Limited Field of View, Decreased-Dose CT.

    Science.gov (United States)

    Delavan, Joshua Adam; Stence, Nicholas V; Mirsky, David M; Gralla, Jane; Fadell, Michael F

    2016-07-01

    Limited z-axis-coverage computed tomography (CT) to evaluate for pediatric lumbar spondylolysis, altering the technique such that the dose to the patient is comparable or lower than radiographs, is currently used at our institution. The objective of the study was to determine whether volumetric 3-dimensional fast spin echo magnetic resonance imaging (3D MRI) can provide equal or greater diagnostic accuracy compared with limited CT in the diagnosis of pediatric lumbar spondylolysis without ionizing radiation. Volumetric 3D MRI can provide equal or greater diagnostic accuracy compared with low-dose CT for pediatric lumbar spondylolysis without ionizing radiation. Clinical review. Level 2. Three pediatric neuroradiologists evaluated 2-dimensional (2D) MRI, 2D + 3D MRI, and limited CT examinations in 42 pediatric patients who obtained imaging for low back pain and suspected spondylolysis. As there is no gold standard for the diagnosis of spondylolysis besides surgery, interobserver agreement and degree of confidence were compared to determine which modality is preferable. Decreased-dose CT provided a greater level of agreement than 2D MRI and 2D + 3D MRI. The kappa for rater agreement with 2D MRI, 2D + 3D MRI, and CT was 0.19, 0.32, and 1.0, respectively. All raters agreed in 31%, 40%, and 100% of cases with 2D MRI, 2D + 3D MRI, and CT. Lack of confidence was significantly lower with CT (0%) than with 2D MRI (30%) and 2D + 3D MRI (25%). For diagnosing spondylolysis, radiologist agreement and confidence trended toward improvement with the addition of a volumetric 3D MRI sequence to standard 2D MRI sequences compared with 2D MRI alone; however, agreement and confidence remain significantly greater using decreased-dose CT when compared with either MRI acquisition. Decreased-dose CT of the lumbar spine remains the optimal examination to confirm a high suspicion of spondylolysis, with dose essentially equivalent to radiographs. If clinical symptoms are not classic for

  6. Contrast-Enhanced Spectral Mammography is Comparable to MRI in the Assessment of Residual Breast Cancer Following Neoadjuvant Systemic Therapy.

    Science.gov (United States)

    Patel, Bhavika K; Hilal, Talal; Covington, Matthew; Zhang, Nan; Kosiorek, Heidi E; Lobbes, Marc; Northfelt, Donald W; Pockaj, Barbara A

    2018-05-01

    To evaluate the performance of contrast-enhanced spectral mammography (CESM) compared to MRI in the assessment of tumor response in breast cancer patients undergoing neoadjuvant systemic therapy (NST). The institutional review board approved this study. From September 2014 to June 2017, we identified patients with pathologically confirmed invasive breast cancer who underwent NST. All patients had both CESM and MRI performed pre- and post-NST with pathological assessment after surgical management. Size of residual malignancy on post-NST CESM and MRI was compared with surgical pathology. Lin concordance and Pearson correlation coefficient were used to assess agreement. Bland-Altman plots were used to visualize the differences between tumor size on imaging and pathology. Sixty-five patients were identified. Mean age was 52.7 (range 30-76) years. Type of NST included chemotherapy in 53 (82%) and endocrine therapy in 12 (18%). Mean tumor size after NST was 14.6 (range 0-105) mm for CESM and 14.2 mm (range 0-75 mm) for MRI compared with 19.6 (range 0-100) mm on final surgical pathology. Equivalence tests demonstrated that mean tumor size measured by CESM (p = 0.009) or by MRI (p = 0.01) was equivalent to the mean tumor size measured by pathology within - 1 and 1-cm range. Comparing CESM versus MRI for assessment of complete response, the sensitivity was 95% versus 95%, specificity 66.7% versus 68.9%, positive predictive value 55.9% versus 57.6%, and negative predictive value 96.7% versus 96.9% respectively. CESM was comparable to MRI in assessing residual malignancy after completion of NST.

  7. 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...

  8. 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.

  9. 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.

  10. 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.

  11. 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 ...

  12. The diagnostic value of MRI and gadolinium-DTPA compared with CT for the diagnosis of bladder tumours

    International Nuclear Information System (INIS)

    Nicolas, V.; Spielmann, R.; Maas, R.; Buecheler, E.; Wagner, B.; Bressel, M.; Porst, H.

    1990-01-01

    In a prospective study, 58 patients with carcinomas of the bladder were examined by CT and MRI; in 48, gadolinium-DTPA was administered intravenously. MRI provided exact staging in 89%, compared with 80% with CT. There was 13% over-staging with CT and 11% with MRI. MRI, unlike CT did not result in any under-staging. In 36 patients a quotient could be calculated from the signal intensity of the tumour and surrounding soft tissues both before and after the intravenous contrast medium and the increased quotient after contrast administration could be estimated. There was a significant increase in the tumour/muscle quotient with a mean of 72±22% (minimum 43%, maximum 153%), corresponding to a marked increase of the signal form the tumour when compared with the precontrast images. This had the following advantages compared with CT: Accurate differentiation between superficial and intramural spread. MRI was better than CT at demonstrating tumours in the roof of the bladder and at the trigone. (orig.) [de

  13. Integrated 18F-FDG PET/MRI compared to MRI alone for identification of local recurrences of soft tissue sarcomas: a comparison trial

    Energy Technology Data Exchange (ETDEWEB)

    Erfanian, Youssef; Grueneisen, Johannes; Wetter, Axel; Forsting, Michael; Umutlu, Lale [University Hospital Essen, University of Duisburg-Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Kirchner, Julian [University Hospital Dusseldorf, University of Dusseldorf, Department of Diagnostic and Interventional Radiology, Dusseldorf (Germany); Podleska, Lars Erik [University Hospital Essen, University of Duisburg-Essen, Sarcoma Surgery Division, Department of General-, Visceral- and Transplantation Surgery, Essen (Germany); Bauer, Sebastian [University Hospital Essen, University of Duisburg-Essen, Division of Solid Tumor Translational Oncology, Department of Medical Oncology, West German Cancer Center, Essen (Germany); Poeppel, Thorsten; Herrmann, Ken [University Hospital Essen, University of Duisburg-Essen, Clinic for Nuclear Medicine, Essen (Germany)

    2017-10-15

    To assess and compare the diagnostic accuracy of PET/MRI and MRI alone for the detection of local recurrences of soft tissue sarcomas (STS) after initial surgical resection of the primary tumors. A total of 41 patients with clinically suspected tumor relapse of STS underwent an {sup 18}F-FDG-PET/MRI examination for assessment of local recurrence. Two experienced physicians interpreted the MRI data and subsequently the PET/MRI datasets in two separate reading sessions and were instructed to identify potential local tumor recurrences. Additionally, the diagnostic confidence in each reading for the identification of malignant lesions was determined. A McNemar test was applied to test for differences of both ratings and a Wilcoxon signed-rank test was used to identify differences of the confidence levels. Histopathological verification and follow-up imaging were applied for standard of reference. Tumor relapse was present in 27/41 patients. Calculated sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for the detection of local tumor recurrence was 82%, 86%, 92%, 71% and 83% for MRI, and 96%, 79%, 90%, 92% and 90% for PET/MRI (p > 0.05). Furthermore, PET/MRI showed significantly higher confidence levels (p < 0.05) for the determination of malignant lesions. Our results endorse {sup 18}F-FDG PET/MRI to be an excellent imaging method in the evaluation of recurrent STS after surgical excision, yielding superior tumor detection when compared to MRI alone. (orig.)

  14. 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.

  15. MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography

    International Nuclear Information System (INIS)

    Weiss, F.; Habermann, C.R.; Sievers, J.; Weil, J.; Adam, G.; Lilje, C.; Razek, W.

    2003-01-01

    Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T 1 -weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness was measured for non-compacted and compacted myocardium and the non-compacted to compacted (N/C) ratio calculated. Results: MRI diagnosed 6 of 8 patients of having NCVM. Myocardial thickness as measured by echocardiography and MRI showed a good correlation in compacted myocardium (r = 0.82) and no correlation in non-compacted myocardium (r = 0.4). In 2 cases, non-compacted myocardium was detected, but echocardiography did not reach the N/C ratio > 2 as required to diagnose NCVM in accordance with the criteria found in the literature. Both patients were also misdiagnosed by MRI performed with Cine-GRE. MRI reached a N/C ratio > 2 in only three patients. Newer TruFisp sequences showed no definite advantages. Extent of non-compaction could be visualized correctly with MRI. (orig.) [de

  16. Diagnostics of Sacroiliitis According to ASAS Criteria: A Comparative Evaluation of Conventional Radiographs and MRI in Patients with a Clinical Suspicion of Spondyloarthropathy. Preliminary Results

    International Nuclear Information System (INIS)

    Sudoł-Szopińska, Iwona; Kwiatkowska, Brygida; Włodkowska-Korytkowska, Monika; Matuszewska, Genowefa; Grochowska, Elżbieta

    2015-01-01

    The objective of this study was a comparative evaluation of radiography and MRI in the diagnostics of sacroiliitis in patients with a clinical diagnosis of spondyloartropathy, according to the current ASAS criteria. Sacroiliac joints radiograms and MRI were conducted in 101 consecutive patients, aged 19–71 yrs (mean age: 40.6 yrs). The patients were referred by a senior rheumatologist, with symptoms of the chronic back pain. The sacroiliac joints were assessed on AP radiograms of the pelvis according to the modified New York criteria for ankylosing spondylitis. MRI was performed to look for active and chronic inflammatory lesions. Of 14 patients with radiographic sacroiliitis according to modified New York criteria, only 50% had sacroiliitis on MRI. The sensitivity and specificity of conventional radiography were 22% and 94% and of MRI were 71% and 90%. Cohen’s kappa coefficient was κ=0.0187, agreement of radiograms and MRI was 58%. Among 86 patients displaying no sacroiliitis on radiograms, MRI showed sacroiliitis in 34 patients (39.5%). Positive predictive value was 0.429, negative predictive value was 0.605. MRI allowed to diagnose sacroiliitis in 39,5 % of patients in preradiographic stage. MRI ruled out the presence of active inflammatory lesions in 60.4% of patients with sacroiliitis on radiograms according to modified New York criteria

  17. 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.)

  18. 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.

  19. 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)

  20. 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).

  1. Rotator cuff tears noncontrast MRI compared to MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Hyun; Yoon, Young Cheol [Sungkyunkwan University, School of Medicine, Department of Radiology, Samsung Medical Center, Gangnam-gu, Seoul (Korea, Republic of); Jung, Jee Young [Chungang University School of Medicine, Department of Radiology, Chungang University Hospital, Seoul (Korea, Republic of); Yoo, Jae Chul [Sungkyunkwan University, School of Medicine, Department of Orthopedic Surgery, Samsung Medical Center, Seoul (Korea, Republic of)

    2015-12-15

    To compare the accuracy of indirect magnetic resonance arthrography and noncontrast magnetic resonance imaging for diagnosing rotator cuff tears. In total, 333 patients who underwent noncontrast magnetic resonance imaging or indirect magnetic resonance arthrography were included retrospectively. Two musculoskeletal radiologists evaluated the images for the presence of supraspinatus-infraspinatus and subscapularis tendon tears. The overall diagnostic performance was calculated using the arthroscopic findings as the reference standard. Statistical differences between the diagnostic performances of the two methods were analyzed. Ninety-six and 237 patients who underwent noncontrast magnetic resonance imaging and indirect magnetic resonance arthrography were assigned into groups A and B, respectively. Sensitivity for diagnosing articular-surface partial-thickness supraspinatus-infraspinatus tendon tear was slightly higher in group B than in group A. Statistical significance was confirmed by multivariate analysis using the generalized estimating equation (p = 0.046). The specificity for diagnosing subscapularis tendon tear (85 % vs. 68 %, p = 0.012) and grading accuracy (57 % vs. 40 %, p = 0.005) was higher in group B than in group A; the differences were statistically significant for one out of two readers. Univariate analysis using the generalized estimating equation showed that the accuracy for diagnosing subscapularis tendon tear in group B was higher than in group A (p = 0.042). There were no statistically significant differences between the diagnostic performances of both methods for any other parameters. Indirect magnetic resonance arthrography may facilitate more accurate diagnosis and grading of subscapularis tendon tears compared with noncontrast magnetic resonance imaging. (orig.)

  2. Rotator cuff tears noncontrast MRI compared to MR arthrography

    International Nuclear Information System (INIS)

    Lee, Ji Hyun; Yoon, Young Cheol; Jung, Jee Young; Yoo, Jae Chul

    2015-01-01

    To compare the accuracy of indirect magnetic resonance arthrography and noncontrast magnetic resonance imaging for diagnosing rotator cuff tears. In total, 333 patients who underwent noncontrast magnetic resonance imaging or indirect magnetic resonance arthrography were included retrospectively. Two musculoskeletal radiologists evaluated the images for the presence of supraspinatus-infraspinatus and subscapularis tendon tears. The overall diagnostic performance was calculated using the arthroscopic findings as the reference standard. Statistical differences between the diagnostic performances of the two methods were analyzed. Ninety-six and 237 patients who underwent noncontrast magnetic resonance imaging and indirect magnetic resonance arthrography were assigned into groups A and B, respectively. Sensitivity for diagnosing articular-surface partial-thickness supraspinatus-infraspinatus tendon tear was slightly higher in group B than in group A. Statistical significance was confirmed by multivariate analysis using the generalized estimating equation (p = 0.046). The specificity for diagnosing subscapularis tendon tear (85 % vs. 68 %, p = 0.012) and grading accuracy (57 % vs. 40 %, p = 0.005) was higher in group B than in group A; the differences were statistically significant for one out of two readers. Univariate analysis using the generalized estimating equation showed that the accuracy for diagnosing subscapularis tendon tear in group B was higher than in group A (p = 0.042). There were no statistically significant differences between the diagnostic performances of both methods for any other parameters. Indirect magnetic resonance arthrography may facilitate more accurate diagnosis and grading of subscapularis tendon tears compared with noncontrast magnetic resonance imaging. (orig.)

  3. 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

  4. 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

  5. Improved brain MRI indices in the acute brain stem infarct sites treated with hydroxyl radical scavengers, Edaravone and hydrogen, as compared to Edaravone alone. A non-controlled study

    Directory of Open Access Journals (Sweden)

    Ono Hirohisa

    2011-06-01

    Full Text Available Abstract Background In acute stage of cerebral infarction, MRI indices (rDWI & rADC deteriorate during the first 3-7 days after the ictus and then gradually normalize in approximately 10 days (pseudonormalization time, although the tissue is already infarcted. Since effective treatments improve these indices significantly and in less than the natural pseudonormalization time, a combined analysis of these changes provides an opportunity for objective evaluation on the effectiveness of various treatments for cerebral infarction. Hydroxyl radicals are highly destructive to the tissue and aggravate cerebral infarction. We treated brainstem infarction patients in acute stage with hydroxyl radical scavengers (Edaravone and hydrogen by intravenous administration and evaluated the effects of the treatment by a serial observation and analysis of these MRI indices. The effects of the treatment were evaluated and compared in two groups, an Edaravone alone group and a combined group with Edaravone and hydrogen, in order to assess beneficial effects of addition of hydrogen. Methods The patients were divided in Edaravone only group (E group. 26 patients and combined treatment group with Edaravone and hydrogen enriched saline (EH group. 8 patients. The extent of the initial hump of rDWI, the initial dip of rADC and pseudo-normalization time were determined in each patient serially and averages of these data were compared in these two groups and also with the natural course in the literatures. Results The initial hump of rDWI reached 2.0 in the E group which was better than 2.5 of the natural course but was not as good as 1.5 of the EH group. The initial dip of rADC was 0.6 in the E group which was close to the natural course but worse than 0.8 of the EH group. Pseudonormalization time of rDWI and rADC was 9 days only in EH group but longer in other groups. Addition of hydrogen caused no side effects. Conclusions Administration of hydroxyl radical scavengers in

  6. 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.)

  7. 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.)

  8. 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

  9. 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).

  10. 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)

  11. 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.)

  12. 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.)

  13. The paediatric wrist revisited - findings of bony depressions in healthy children on radiographs compared to MRI

    International Nuclear Information System (INIS)

    Avenarius, Derk M.F.; Eldevik, Petter; Ording Mueller, Lil-Sofie; Owens, Catherine M.; Rosendahl, Karen

    2012-01-01

    The presence of erosions is used for diagnosis and monitoring of disease activity in juvenile idiopathic arthritis (JIA). Assessment of carpal bone erosions in children is challenging due to lack of normal references. To define normal appearances of bony depressions in the wrist on radiographs and MRI. MRI and radiography of the wrist were performed in 88 healthy children, 5-15 years of age. We assessed the number of bony depressions within the carpals/proximal metacarpals on both modalities, separately and combined. A total of 75 carpal depressions were identified on radiography compared to 715 on MRI. The number of bony depressions identified radiographically showed no statistically significant difference across age-groups. Within the metacarpals, there was no significant difference between bony depressions identified by MRI or radiography, except at the bases of the second metacarpal. Bony depressions that resemble erosions are normal findings in the wrist in children. MRI identifies more depressions than radiographs in the carpus. Some bony depressions occur at typical locations and should be accounted for when assessing the wrist in JIA to avoid overstaging. (orig.)

  14. [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.

  15. 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)

  16. 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)

  17. 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

  18. 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

  19. Comparative benefits and limitations of 18F-FDG PET and CT-MRI in documented or suspected recurrent cervical cancer

    International Nuclear Information System (INIS)

    Yen, Tzu-Chen; Ma, Shih-Ya; Lai, Chyong-Huey; Huang, Kuan-Gen; Huang, Huei-Jean; Chang, Ting-Chang; Hong, Ji-Hong; Hsueh, Swei; Lin, Wuu-Jyh; Ng, Koon-Kwan

    2006-01-01

    The purpose of this study was to assess the comparative benefits and limitations of 18 F-fluorodeoxyglucose (FDG) PET and CT-MRI in documented or suspected recurrence of cervical cancer after primary treatment. Three patient groups were enrolled. Group A patients had biopsy-documented recurrent or persistent cervical cancer. Group B patients had suspicion of recurrent tumour on CT-MRI without biopsy proof and were potentially curable. Group C patients were in complete remission after previous definitive treatment for histologically confirmed cervical carcinoma but had elevated serum squamous cell carcinoma antigen (tumour marker) levels despite negative CT-MRI. Clinical management decisions were recorded with CT-MRI alone and with additional FDG PET. Discordances and concordances between CT-MRI and FDG PET results were identified and related to final diagnosis as based on histopathology or follow-up. A total of 150 patients (ten regions per patient) were eligible for analysis, with 58 in group A, 52 in group B and 40 in group C. For the 149 discordant regions, 126 (84.6%) had final diagnoses. Of these final diagnoses, there was additional benefit from FDG PET over CT-MRI in 73.8% (93/126), with FDG PET correcting false negatives (FNs) on CT-MRI in 74.2% (69/93) and correcting false positives (FPs) on CT-MRI in 25.8% (24/93). Among lesions confirmed by FDG PET, 75.4% (52/69) were extra-pelvic. There was additional benefit of CT-MRI compared with FDG PET in 26.2% (33/126): in nine (27.3%) CT-MRI results were shown to be true positive (TP) whereas FDG PET yielded FN results, while in 24 (72.7%) CT-MRI corrected FP results on FDG PET. Among the nine FNs on FDG PET that were identified by CT-MRI, four were extra-pelvic. Among the FPs on FDG PET that were excluded by CT-MRI, 79.2% (19/24) were extra-pelvic. For recurrent cervical cancer, the benefits of FDG PET exceed those of CT-MRI owing to the ability of FDG PET to identify extra-pelvic metastases and its higher

  20. 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.

  1. 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...

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. 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)

  7. Clinical Evaluation of PET Image Quality as a Function of Acquisition Time in a New TOF-PET/MRI Compared to TOF-PET/CT--Initial Results.

    Science.gov (United States)

    Zeimpekis, Konstantinos G; Barbosa, Felipe; Hüllner, Martin; ter Voert, Edwin; Davison, Helen; Veit-Haibach, Patrick; Delso, Gaspar

    2015-10-01

    The purpose of this study was to compare only the performance of the PET component between a TOF-PET/CT (henceforth noted as PET/CT) scanner and an integrated TOF-PET/MRI (henceforth noted as PET/MRI) scanner concerning image quality parameters and quantification in terms of standardized uptake value (SUV) as a function of acquisition time (a surrogate of dose). The CT and MR image quality were not assessed, and that is beyond the scope of this study. Five brain and five whole-body patients were included in the study. The PET/CT scan was used as a reference and the PET/MRI acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of the emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts, and noise were evaluated. SUV measurements were taken in the liver and in the white matter to compare quantification. Quantitative evaluation showed strong correlation between PET/CT and PET/MRI brain SUVs. Liver correlation was good, however, with lower uptake estimation in PET/MRI, partially justified by bio-redistribution. The clinical evaluation showed that PET/MRI offers higher image quality and sharpness with lower levels of noise and artifacts compared to PET/CT with reduced acquisition times for whole-body scans while for brain scans there is no significant difference. The TOF-PET/MRI showed higher image quality compared to TOF-PET/CT as tested with reduced imaging times. However, this result accounts mainly for body imaging, while no significant differences were found in brain imaging.

  8. Comparative magnetic resonance imaging of renal space-occupying lesions with a high and a low field MRI system

    International Nuclear Information System (INIS)

    Gehl, H.B.; Lorch, H.; Amblank, O.B.M.; Engerhoff, B.; Weiss, H.D.

    1998-01-01

    Purpose: A prospective study of the diagnostic accuracy and image quality of two MRI systems in the detection of renal tumors was investigated. Materials and Methods: 34 patients with the clinical suspicion of a space-occupying renal lesion were examined by MRI with a low field (0.2 Tesla magnet) and a high field (1.5 Tesla magnet) for comparison. An 'informed' and a 'blind' observer evaluated all of the MR images. In addition, the signal-to-noise and contrast-to-noise ratios were evaluated as second quality parameters. Results: In 29 cases the results could be compared with a confirmed release diagnosis. Diagnostic accuracy was comparable with both systems (Sensitivity for both observer on LF apparatus: 83%, HF apparatus: 81%) although the signal-to-noise and contrast-to-noise ratios were significantly poorer at low field. Conclusions: The low field system in comparable to the high field MRI for detection and differentiation of renal space-occupying lesions. (orig.) [de

  9. Comparing different stimulus configurations for population receptive field mapping in human fMRI

    Directory of Open Access Journals (Sweden)

    Ivan eAlvarez

    2015-02-01

    Full Text Available Population receptive field (pRF mapping is a widely used approach to measuring aggregate human visual receptive field properties by recording non-invasive signals using functional MRI. Despite growing interest, no study to date has systematically investigated the effects of different stimulus configurations on pRF estimates from human visual cortex. Here we compared the effects of three different stimulus configurations on a model-based approach to pRF estimation: size-invariant bars and eccentricity-scaled bars defined in Cartesian coordinates and traveling along the cardinal axes, and a novel simultaneous ‘wedge and ring’ stimulus defined in polar coordinates, systematically covering polar and eccentricity axes. We found that the presence or absence of eccentricity scaling had a significant effect on goodness of fit and pRF size estimates. Further, variability in pRF size estimates was directly influenced by stimulus configuration, particularly for higher visual areas including V5/MT+. Finally, we compared eccentricity estimation between phase-encoded and model-based pRF approaches. We observed a tendency for more peripheral eccentricity estimates using phase-encoded methods, independent of stimulus size. We conclude that both eccentricity scaling and polar rather than Cartesian stimulus configuration are important considerations for optimal experimental design in pRF mapping. While all stimulus configurations produce adequate estimates, simultaneous wedge and ring stimulation produced higher fit reliability, with a significant advantage in reduced acquisition time.

  10. Functional MRI of the patellofemoral joint: comparison of ultrafast MRI, motion-triggered cine MRI and static MRI

    Energy Technology Data Exchange (ETDEWEB)

    Muhle, C. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Brossmann, J. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Melchert, U.H. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Schroeder, C. [Radiologische Abt., Universitaets-Kinderklinik, Christian-Albrechts-Universitaet, Kiel (Germany); Boer, R. de [Philips Medical Systems, Best (Netherlands); Spielmann, R.P. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Heller, M. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany)

    1995-12-31

    To evaluate the feasibility and usefulness of ultrafast MRI (u), patellar tracking from 30 of flexion to knee extension (0 ) was analysed and compared with motion-triggered cine MRI (m) and a static MRI technique (s). The different imaging methods were compared in respect of the patellofemoral relationship, the examination time and image quality. Eight healthy subjects and four patients (in total 18 joints) with patellar subluxation or luxation were examined. Significant differences between the static MRI series without quadriceps contraction and the functional MRI studies (motion-triggered cine MRI and ultrafast MRI) were found for the patellar tilt angle. In the dynamic joint studies there was no statistical difference of the regression coefficients between the motion-triggered cine MRI studies and the ultrafast MRI studies. The findings of the functional MRI studies compared with the static MRI images were significantly different for the lateralisation of the patella, expressed by the lateral patellar displacement and bisect offset. No significant differences in patellar lateralisation were found between motion-triggered cine MRI and ultrafast MRI. Ultrafast MRI was superior to motion-triggered cine MRI in terms of the reduction in imaging time and improvement of the image quality. (orig.)

  11. Functional MRI of the patellofemoral joint: comparison of ultrafast MRI, motion-triggered cine MRI and static MRI

    International Nuclear Information System (INIS)

    Muhle, C.; Brossmann, J.; Melchert, U.H.; Schroeder, C.; Boer, R. de; Spielmann, R.P.; Heller, M.

    1995-01-01

    To evaluate the feasibility and usefulness of ultrafast MRI (u), patellar tracking from 30 of flexion to knee extension (0 ) was analysed and compared with motion-triggered cine MRI (m) and a static MRI technique (s). The different imaging methods were compared in respect of the patellofemoral relationship, the examination time and image quality. Eight healthy subjects and four patients (in total 18 joints) with patellar subluxation or luxation were examined. Significant differences between the static MRI series without quadriceps contraction and the functional MRI studies (motion-triggered cine MRI and ultrafast MRI) were found for the patellar tilt angle. In the dynamic joint studies there was no statistical difference of the regression coefficients between the motion-triggered cine MRI studies and the ultrafast MRI studies. The findings of the functional MRI studies compared with the static MRI images were significantly different for the lateralisation of the patella, expressed by the lateral patellar displacement and bisect offset. No significant differences in patellar lateralisation were found between motion-triggered cine MRI and ultrafast MRI. Ultrafast MRI was superior to motion-triggered cine MRI in terms of the reduction in imaging time and improvement of the image quality. (orig.)

  12. Comparative Studies for What?

    Directory of Open Access Journals (Sweden)

    Pedro Guedes de Carvalho

    2017-12-01

    Full Text Available ISCPES stands for International Society for Comparative Physical Education and Sports and it is going to celebrate its 40th anniversary in 2018. Since the beginning (Israel 1978 the main goals of the Society were established under a worldwide mind set considering five continents and no discrimination of any kind. The founders wanted to compare Physical Education and Sports across the world, searching for the best practices deserving consideration and applied on the purpose of improving citizen quality of life. The mission still stands for “Compare to learn and improve”. As all the organizations lasting for 39 years, ISCPES experienced several vicissitudes, usually correlated with world economic cycles, social and sports changes, which are in ISS journal articles - International Sport Studies. ISS journal is Scopus indexed, aiming to improve its quality (under evaluation to reach more qualified students, experts, professionals and researchers; doing so it will raise its indexation, which we know it is nowadays a more difficult task. First, because there are more journals trying to compete on this academic fierce competitive market; secondly, because the basic requirements are getting more and more hard to gather in the publishing environment around Physical Education and Sports issues. However, we can promise this will be one of our main strategic goals. Another goal I would like to address on this Editorial is the language issue. We have this second strategic goal, which is to reach most of languages spoken in different continents; besides the English language, we will reach Chinese, Spanish and Portuguese speaking countries. For that reason, we already defined that all the abstracts in English will be translated into Chinese, Spanish and Portuguese words so people can find them on any search browser. That will expand the demand for our journal and articles, increasing the number of potential readers. Of course this opportunity, given by

  13. Operations dashboard: comparative study

    Science.gov (United States)

    Ramly, Noor Nashriq; Ismail, Ahmad Zuhairi; Aziz, Mohd Haris; Ahmad, Nurul Haszeli

    2011-10-01

    In this present days and age, there are increasing needs for companies to monitor application and infrastructure health. Apart from having proactive measures to secure their application and infrastructure, many see monitoring dashboards as crucial investment in disaster preparedness. As companies struggle to find the best solution to cater for their needs and interest for monitoring their application and infrastructure's health, this paper summarizes the studies made on several known off-the-shelf operations dashboard and in-house developed dashboard. A few criteria of good dashboard are collected from previous studies carried out by several researchers and rank them according to importance and business needs. The finalized criteria that will be discussed in later sections are data visualization, performance indicator, dashboard personalization, audit capability and alert/ notification. Comparative studies between several popular dashboards were then carried out to determine whether they met these criteria that we derived from the first exercise. The findings hopefully can be used to educate and provide an overview of selecting the best IT application and infrastructure operations dashboard that suit business needs, thus become the main contribution of this paper.

  14. 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

  15. Intermittent compared to continuous real-time fMRI neurofeedback boosts control over amygdala activation.

    Science.gov (United States)

    Hellrung, Lydia; Dietrich, Anja; Hollmann, Maurice; Pleger, Burkhard; Kalberlah, Christian; Roggenhofer, Elisabeth; Villringer, Arno; Horstmann, Annette

    2018-02-01

    Real-time fMRI neurofeedback is a feasible tool to learn the volitional regulation of brain activity. So far, most studies provide continuous feedback information that is presented upon every volume acquisition. Although this maximizes the temporal resolution of feedback information, it may be accompanied by some disadvantages. Participants can be distracted from the regulation task due to (1) the intrinsic delay of the hemodynamic response and associated feedback and (2) limited cognitive resources available to simultaneously evaluate feedback information and stay engaged with the task. Here, we systematically investigate differences between groups presented with different variants of feedback (continuous vs. intermittent) and a control group receiving no feedback on their ability to regulate amygdala activity using positive memories and feelings. In contrast to the feedback groups, no learning effect was observed in the group without any feedback presentation. The group receiving intermittent feedback exhibited better amygdala regulation performance when compared with the group receiving continuous feedback. Behavioural measurements show that these effects were reflected in differences in task engagement. Overall, we not only demonstrate that the presentation of feedback is a prerequisite to learn volitional control of amygdala activity but also that intermittent feedback is superior to continuous feedback presentation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. 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.)

  17. 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.)

  18. ACR/EULAR Definitions of Remission Are Associated with Lower Residual Inflammatory Activity Compared with DAS28 Remission on Hand MRI in Rheumatoid Arthritis.

    Science.gov (United States)

    Lisbona, Maria Pilar; Solano, Albert; Ares, Jesús; Almirall, Miriam; Salman-Monte, Tarek Carlos; Maymó, Joan

    2016-09-01

    To determine the level of residual inflammation [synovitis, bone marrow edema (BME), tenosynovitis, and total inflammation] quantified by hand magnetic resonance imaging (h-MRI) in patients with rheumatoid arthritis (RA) in remission according to 3 different definitions of clinical remission, and to compare these remission definitions. A cross-sectional study. To assess the level of residual MRI inflammation in remission, cutoff levels associated to remission and median scores of MRI residual inflammatory lesions were calculated. Data from an MRI register of patients with RA who have various levels of disease activity were used. These were used for the analyses: synovitis, BME according to the Rheumatoid Arthritis Magnetic Resonance Imaging Scoring system, tenosynovitis, total inflammation, and disease activity composite measures recorded at the time of MRI. Receiver-operating characteristic analysis was used to identify the best cutoffs associated with remission for each inflammatory lesion on h-MRI. Median values of each inflammatory lesion for each definition of remission were also calculated. A total of 388 h-MRI sets of patients with RA with different levels of disease activity, 130 in remission, were included. Cutoff values associated with remission according to the Simplified Disease Activity Index (SDAI) ≤ 3.3 and the Boolean American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) definitions for BME and tenosynovitis (1 and 3, respectively) were lower than BME and tenosynovitis (2 and 5, respectively) for the Disease Activity Score on 28 joints (DAS28) ≤ 2.6. Median scores for synovitis, BME, and total inflammation were also lower for the SDAI and Boolean ACR/EULAR remission criteria compared with DAS28. Patients with RA in remission according to the SDAI and Boolean ACR/EULAR definitions showed lower levels of MRI-detected residual inflammation compared with DAS28.

  19. Comparative waste forms study

    International Nuclear Information System (INIS)

    Wald, J.W.; Lokken, R.O.; Shade, J.W.; Rusin, J.M.

    1980-12-01

    A number of alternative process and waste form options exist for the immobilization of nuclear wastes. Although data exists on the characterization of these alternative waste forms, a straightforward comparison of product properties is difficult, due to the lack of standardized testing procedures. The characterization study described in this report involved the application of the same volatility, mechanical strength and leach tests to ten alternative waste forms, to assess product durability. Bulk property, phase analysis and microstructural examination of the simulated products, whose waste loading varied from 5% to 100% was also conducted. The specific waste forms investigated were as follows: Cold Pressed and Sintered PW-9 Calcine; Hot Pressed PW-9 Calcine; Hot Isostatic Pressed PW-9 Calcine; Cold Pressed and Sintered SPC-5B Supercalcine; Hot Isostatic pressed SPC-5B Supercalcine; Sintered PW-9 and 50% Glass Frit; Glass 76-68; Celsian Glass Ceramic; Type II Portland Cement and 10% PW-9 Calcine; and Type II Portland Cement and 10% SPC-5B Supercalcine. Bulk property data were used to calculate and compare the relative quantities of waste form volume produced at a spent fuel processing rate of 5 metric ton uranium/day. This quantity ranged from 3173 L/day (5280 Kg/day) for 10% SPC-5B supercalcine in cement to 83 L/day (294 Kg/day) for 100% calcine. Mechanical strength, volatility, and leach resistance tests provide data related to waste form durability. Glass, glass-ceramic and supercalcine ranked high in waste form durability where as the 100% PW-9 calcine ranked low. All other materials ranked between these two groupings

  20. 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)

  1. 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)

  2. 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

  3. 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.)

  4. Comparative utility of MRI perfusion with MSIDR and DWIBS for the characterization of breast tumors

    International Nuclear Information System (INIS)

    Zhang, Bing; Zhu, Bin; Li, Ming

    2012-01-01

    Background. In recent years, breast magnetic resonance imaging (MRI) has been used to evaluate the morphology and functional markers of breast lesions, which might influence local staging and surgical planning. Purpose. To evaluate the feasibility of a one stop MRI protocol combined with diffusion-weighted imaging with background body signal suppression (DWIBS), T2*-weighted perfusion imaging (T2*-PWI) and delayed contrast-enhanced T1-weighted MRI (T1W-C+). Material and Methods. All experiments were conducted with a 3-T clinical MRI scanner. The apparent diffusion coefficient (ADC) and detectability of lesions in DWIBS, the maximal signal intensity drop rate (MSIDR) in T2*-PWI and the intensity increasing rate (IIR) on T1W-C+ were compared between breast malignancies (n = 29) and benign lesions (n = 31). The time-signal curves in the T2*-PWI sequences were classified into two subtypes (a and b) according to the end of the curve. The ADC, MSIDR, the first maximal signal intensity decrease time (MSIDT), and IIR between the malignant and benign lesions were statistically analyzed by unpaired t-tests. Results. Overall, 90% of the lesions were detected by DWIBS. There were significant differences in ADC, MSIDR, and IIR between the carcinomas and benign lesions. The Ib subtype in T2*-PWI demonstrated a specificity of 66.7% in differentiating between carcinomas and benign lesions. At a fixed specificity of 93.5%, the MSIDR, IIR, and ADC differentiated breast carcinomas from benign lesions with sensitivities of 82.8%, 44.8%, and 86.2%, respectively. Conclusion. DWIBS might be a compensation sequence for detecting breast lesions in pre-contrast sequences. MSIDR from T2*-PWI had the best specificity index, and the two subtypes in the T2*-PWI curve were helpful in the differential diagnosis of carcinomas from benign lesions

  5. Comparing consistency of R2* and T2*-weighted BOLD analysis of resting state fetal fMRI

    Science.gov (United States)

    Seshamani, Sharmishtaa; Blazejewska, Anna I.; Gatenby, Christopher; Mckown, Susan; Caucutt, Jason; Dighe, Manjiri; Studholme, Colin

    2015-03-01

    Understanding when and how resting state brain functional activity begins in the human brain is an increasing area of interest in both basic neuroscience and in the clinical evaluation of the brain during pregnancy and after premature birth. Although fMRI studies have been carried out on pregnant women since the 1990's, reliable mapping of brain function in utero is an extremely challenging problem due to the unconstrained fetal head motion. Recent studies have employed scrubbing to exclude parts of the time series and whole subjects from studies in order to control the confounds of motion. Fundamentally, even after correction of the location of signals due to motion, signal intensity variations are a fundamental limitation, due to coil sensitivity and spin history effects. An alternative technique is to use a more parametric MRI signal derived from multiple echoes that provides a level of independence from basic MRI signal variation. Here we examine the use of R2* mapping combined with slice based multi echo geometric distortion correction for in-utero studies. The challenges for R2* mapping arise from the relatively low signal strength of in-utero data. In this paper we focus on comparing activation detection in-utero using T2W and R2* approaches. We make use a subset of studies with relatively limited motion to compare the activation patterns without the additional confound of significant motion. Results at different gestational ages indicate comparable agreement in many activation patterns when limited motion is present, and the detection of some additional networks in the R2* data, not seen in the T2W results.

  6. 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

  7. 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.

  8. 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

  9. Comparative evaluation of 11C-MET PET-CT and MRI for GTV delineation in precision radiotherapy for gliomas

    International Nuclear Information System (INIS)

    Wang Ru; Qian Liting; Wang Shicun; Liu Wei; Luo Wenguang; Zhang Hongbo; Li Guanghu; Hu Zhigang; Liu Lei

    2014-01-01

    Objective: To evaluate the difference between MRI and 11 C-MET PET-CT for gross tumor volume (GTV) delineation in the precision radiotherapy for gliomas. Methods: Six patients with a pathologically confirmed diagnosis of gliomas were selected for target delineation. Five physicians in our department were called to delineate the GTV based on the preoperative MRI and 11 C-MET PET-CT images of these patients. The GTVs based on the two methods were compared. Results: There was no significant difference between the GTVs based on MRI and 11 C-MET PET-CT (P=0.917), and their coefficients of variation were also similar (P=0.600). The coincidences of GTVs were different among the patients, with a maximum value of 73.0% and a minimum value of 51.8%. GTV showed no significant difference when defined by different physicians on MRI and PET-CT (P=0.709); the biggest difference was 27.66 cm 3 on PET-CT and 40.37 cm 3 on MRI. Conclusions: The boundaries of gliomas defined on MRI and PET-CT are different. The GTVs delineated by different physicians on MRI and PET-CT are similar, and the biggest difference on PET-CT is smaller than that on MRI, which suggests that 11 C-MET PET-CT is a more direct way for displaying GTV. (authors)

  10. 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

  11. 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...

  12. 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…

  13. Mobile OS Comparative Study

    OpenAIRE

    Joseph, Jyothy; K, Shinto Kurian

    2013-01-01

    In the fast growing mobile revolutionary era, many operating systems are playing vital role in present market. This study is intending to identify the apt and secure mobile based on mobile operating systems capability and user requirements.

  14. 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.

  15. 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)

  16. Comparative safety of gadodiamide, dimeglumine gadopentetate and meglumine gadoterate in MRI of the central nervous system

    International Nuclear Information System (INIS)

    Chanalet, S.; Bruneton, J.N.; Masson, B.; Boyer, L.; Laffont, J.

    1995-01-01

    The development of new non-ionic magnetic resonance (MR) contrast media as gadodiamide injection increased the choice of paramagnetic contrast agents available in MR of the central nervous system (CNS). The purpose of our paper was to compare at the dose of 0.1 mmol/kg b.w. the safety of gadodiamide (Gd-DTPA-BMA) to gadopentetate dimeglumine (Gd-DTPA) and to gadoterate meglumine (Gd-DOTA) in two multi centric double-blind studies. A total of 551 patients were enrolled with 143 patients in the Gd-DTPA group, 132 patients in the Gd-DOTA group and 276 patients in the Gd-DTPA-BMA group. Safety was assessed by recording the adverse events up to 24 hours after the injection. One or more adverse events were recorded in 14% of the Gd-DTPA patients, in 15.1% of the Gd-DOTA patients and in 11.6% of the Gd-DTPA-BMA patients. These reactions were related to the contrast media in 9.1%, 13.6% and 8.7% of the cases respectively. Their intensity was defined as mild in 8.4% of the patients in the Gd-DTPA group, in 13.6% of the patients in the Gd-DOTA group and in 8.3% of the patients in the Gd-DTPA-BMA group. No severe reaction or death were recorded. An injection-site reaction (heat, coldness, pain) has been observed in 43% of the cases although an adverse event other than local reactions (headache, dizziness, nausea) has been noticed in 57% of the cases. No significant statistical difference was observed between the groups. Gadodiamide is a safe and effective contrast agent in MRI of the CNS in comparison with Gd-DTPA and Gd-DOTA currently in routine use

  17. The diagnostic performance of radiography for detection of osteoarthritis-associated features compared with MRI in hip joints with chronic pain

    International Nuclear Information System (INIS)

    Xu, Li; Hayashi, Daichi; Guermazi, Ali; Hunter, David J.; Li, Ling; Winterstein, Anton; Bohndorf, Klaus; Roemer, Frank W.

    2013-01-01

    To evaluate the diagnostic performance of radiography for the detection of MRI-detected osteoarthritis-associated features in various articular subregions of the hip joint. Forty-four patients with chronic hip pain (mean age, 63.3 ± 9.5 years), who were part of the Hip Osteoarthritis MRI Scoring (HOAMS) cohort, underwent both weight-bearing anteroposterior pelvic radiography and 1.5 T MRI. The HOAMS study was a prospective observational study involving 52 subjects, conducted to develop a semiquantitative MRI scoring system for hip osteoarthritis features. In the present study, eight subjects were excluded because of a lack of radiographic assessment. On radiography, the presence of superior and medial joint space narrowing, superior and inferior acetabular/femoral osteophytes, acetabular subchondral cysts, and bone attrition of femoral head was noted. On MRI, cartilage, osteophytes, subchondral cysts, and bone attrition were evaluated in the corresponding locations. Diagnostic performance of radiography was compared with that of MRI, and the area under curve (AUC) was calculated for each pathological feature. Compared with MRI, radiography provided high specificity (0.76-0.90) but variable sensitivity (0.44-0.78) for diffuse cartilage damage (using JSN as an indirect marker), femoral osteophytes, acetabular subchondral cysts and bone attrition of the femoral head, and a low specificity (0.42 and 0.58) for acetabular osteophytes. The AUC of radiography for detecting overall diffuse cartilage damage, marginal osteophytes, subchondral cysts and bone attrition was 0.76, 0.78, 0.67, and 0.82, respectively. Diagnostic performance of radiography is good for bone attrition, fair for marginal osteophytes and cartilage damage, but poor for subchondral cysts. (orig.)

  18. The diagnostic performance of radiography for detection of osteoarthritis-associated features compared with MRI in hip joints with chronic pain

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Li [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Beijing Jishuitan Hospital, Department of Radiology, Beijing (China); Hayashi, Daichi; Guermazi, Ali [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Hunter, David J. [University of Sydney, Department of Medicine, Sydney (Australia); Li, Ling [New England Baptist Hospital, Division of Research, Boston, MA (United States); Winterstein, Anton; Bohndorf, Klaus [Klinikum Augsburg, Department of Radiology, Augsburg (Germany); Roemer, Frank W. [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Klinikum Augsburg, Department of Radiology, Augsburg (Germany); University of Erlangen, Department of Radiology, Erlangen (Germany)

    2013-10-15

    To evaluate the diagnostic performance of radiography for the detection of MRI-detected osteoarthritis-associated features in various articular subregions of the hip joint. Forty-four patients with chronic hip pain (mean age, 63.3 {+-} 9.5 years), who were part of the Hip Osteoarthritis MRI Scoring (HOAMS) cohort, underwent both weight-bearing anteroposterior pelvic radiography and 1.5 T MRI. The HOAMS study was a prospective observational study involving 52 subjects, conducted to develop a semiquantitative MRI scoring system for hip osteoarthritis features. In the present study, eight subjects were excluded because of a lack of radiographic assessment. On radiography, the presence of superior and medial joint space narrowing, superior and inferior acetabular/femoral osteophytes, acetabular subchondral cysts, and bone attrition of femoral head was noted. On MRI, cartilage, osteophytes, subchondral cysts, and bone attrition were evaluated in the corresponding locations. Diagnostic performance of radiography was compared with that of MRI, and the area under curve (AUC) was calculated for each pathological feature. Compared with MRI, radiography provided high specificity (0.76-0.90) but variable sensitivity (0.44-0.78) for diffuse cartilage damage (using JSN as an indirect marker), femoral osteophytes, acetabular subchondral cysts and bone attrition of the femoral head, and a low specificity (0.42 and 0.58) for acetabular osteophytes. The AUC of radiography for detecting overall diffuse cartilage damage, marginal osteophytes, subchondral cysts and bone attrition was 0.76, 0.78, 0.67, and 0.82, respectively. Diagnostic performance of radiography is good for bone attrition, fair for marginal osteophytes and cartilage damage, but poor for subchondral cysts. (orig.)

  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. Comparative Packaging Study

    Science.gov (United States)

    Perchonok, Michele H.; Oziomek, Thomas V.

    2009-01-01

    Future long duration manned space flights beyond low earth orbit will require the food system to remain safe, acceptable and nutritious. Development of high barrier food packaging will enable this requirement by preventing the ingress and egress of gases and moisture. New high barrier food packaging materials have been identified through a trade study. Practical application of this packaging material within a shelf life test will allow for better determination of whether this material will allow the food system to meet given requirements after the package has undergone processing. The reason to conduct shelf life testing, using a variety of packaging materials, stems from the need to preserve food used for mission durations of several years. Chemical reactions that take place during longer durations may decrease food quality to a point where crew physical or psychological well-being is compromised. This can result in a reduction or loss of mission success. The rate of chemical reactions, including oxidative rancidity and staling, can be controlled by limiting the reactants, reducing the amount of energy available to drive the reaction, and minimizing the amount of water available. Water not only acts as a media for microbial growth, but also as a reactant and means by which two reactants may come into contact with each other. The objective of this study is to evaluate three packaging materials for potential use in long duration space exploration missions.

  2. Evaluation of right ventricular volume and function by 2D and 3D echocardiography compared to MRI

    DEFF Research Database (Denmark)

    Kjaergaard, Jesper; Petersen, Claus Leth; Kjaer, Andreas

    2005-01-01

    : Thirty-four subjects with (a) prior inferior ST-elevation myocardial infarction (n=17), (b) a history of pulmonary embolism and persistent dyspnea (n=7) or (c) normal subjects (n=10) had 2D and 3D echocardiography, SPECT and MRI within 24h. End-diastolic volume and peak tricuspid regurgitation velocity...... were increased in patients with a history of pulmonary embolism compared to healthy subjects, 130+/-26 ml vs. 94+/-26 ml, P... volume showed significant correlation to RV volumes by MRI. Tricuspid annular plane systolic excursion (TAPSE) had the better correlation to RVEF by MRI, r=0.48, P

  3. 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)

  4. 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.

  5. Quantitative and Qualitative Assessment of Pulmonary Emphysema with T2-Weighted PROPELLER MRI in a High-Risk Population Compared to Low-Dose CT.

    Science.gov (United States)

    Meier-Schroers, Michael; Sprinkart, Alois Martin; Becker, Manuel; Homsi, Rami; Thomas, Daniel

    2018-03-07

     To determine the suitability of T2-weighted PROPELLER MRI for the assessment of pulmonary emphysema.  60 participants in a lung cancer screening program (30 subjects with pulmonary emphysema, and 30 control subjects without emphysema) were included for this retrospective study. All subjects were examined with low-dose CT (LDCT) and MRI within the screening program. The use of a T2-weighted PROPELLER sequence for the assessment of emphysema was analyzed and correlated with the results of LDCT. The presence and the extent of pulmonary emphysema were first assessed qualitatively using a three-point score, and then quantitatively with a semi-automated software program to obtain emphysema indices.  All 30 cases with pulmonary emphysema were accurately detected by MRI. There were 3 cases with emphysema according to MRI without emphysematous changes on LDCT (false-positive results). The qualitative scores as well as the emphysema indices were significantly higher in the emphysema group compared to the control group for MRI and LDCT (p emphysema group and r = 0.668/p emphysema index: r = 0.960/p emphysema group and r = 0.746/p pulmonary emphysema may be assessed qualitatively and quantitatively by T2-weighted PROPELLER MRI with very good correlation to LDCT.   · T2-weighted PROPELLER MRI may be suitable for the assessment of pulmonary emphysema.. · There was significant correlation between MRI and LDCT regarding qualitative scores and quantitative emphysema indices in our study with correlation coefficients for different subgroups ranging from r = 0.668 to r = 0.960.. · T2-weighted PROPELLER MRI may have the potential to be used for follow-up examinations in patients with severe emphysema to avoid radiation exposure of repeated CTs.. · Meier-Schroers M, Sprinkart AM, Becker M et al. Quantitative and Qualitative Assessment of Pulmonary Emphysema with T2-Weighted PROPELLER MRI in a High-Risk Population Compared to Low-Dose CT

  6. 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

  7. 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

  8. 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.)

  9. Cine MRI of dissecting aneurysm

    International Nuclear Information System (INIS)

    Takaki, Hajime

    1991-01-01

    Cine MRI was performed in 25 cases of aortic dissection and comparative study among cine MRI, spin-echo static MRI, contrast-enhanced CT and intravenous digital subtraction angiography (IVDSA) was made. Cine MRI accurately detected aortic dissection. It was most accurate among various diagnostic methods in demonstration of entry site of dissection. Take-off of renal artery and its relation to true and false channels was also accurately demonstrated by cine MRI. The above results suggest that cine MRI can be an important diagnostic modality with almost equal diagnostic quality to those of conventional angiography. However, further technical improvement to shorten the imaging time seems necessary to replace angiography. (author)

  10. An audit comparing the reporting of staging MRI scans for rectal cancer with the London Cancer Alliance (LCA) guidelines.

    Science.gov (United States)

    Siddiqui, M R S; Shanmuganandan, A P; Rasheed, S; Tekkis, P; Brown, G; Abulafi, A M

    2017-11-01

    This article focuses on the audit and assessment of clinical practice before and after introduction of MRI reporting guidelines. Standardised proforma based reporting may improve quality of MRI reports. Uptake of the use may be facilitated by endorsement from regional and national cancer organisations. This audit was divided into 2 phases. MRI reports issued between April 2014 and June 2014 were included in the first part of our audit. Phase II included MRI reports issued between April 2015 and June 2015. 14 out of 15 hospitals that report MRI scans in the LCA responded to our audit proposal. The completion rate of key MRI metrics/metrics was better in proforma compared to prose reports both before (98% vs 73%; p < 0.05) and after introduction of the guidelines (98% vs 71%; p < 0.05). There was an approximate doubling of proforma reporting after the introduction of guidelines and workshop interventions (39% vs 65%; p < 0.05). Evaluation of locally advanced cancers (tumours extending to or beyond the circumferential resection margin) for beyond TME surgery was reported in 3% of prose reports vs. 42% in proformas. Incorporation of standardised reporting in official guidelines improved the uptake of proforma based reporting. Proforma based reporting captured more MRI reportable items compared to prose summaries, before and after the implementation of guidelines. MRI reporting of advanced cancers for beyond TME surgery falls short of acceptable standards but is more detailed in proforma based reports. Further work to improve completion especially in beyond TME reporting is required. Copyright © 2017 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

  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. Diagnostic accuracy of {sup 18}F-FDG PET/CT compared with that of contrast-enhanced MRI of the breast at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Magometschnigg, Heinrich F.; Baltzer, Pascal A.; Fueger, Barbara; Helbich, Thomas H.; Weber, Michael [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Vienna (Austria); Karanikas, Georgios [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Vienna (Austria); Dubsky, Peter [Medical University of Vienna, Department of Surgery, Vienna (Austria); Rudas, Margaretha [Medical University of Vienna, Department of Pathology, Vienna (Austria); Pinker, Katja [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Vienna (Austria); Molecular Imaging and Therapy Service, Memorial Sloan Kettering Cancer Center, New York (United States)

    2015-10-15

    To compare the diagnostic accuracy of prone {sup 18}F-FDG PET/CT with that of contrast-enhanced MRI (CE-MRI) at 3 T in suspicious breast lesions. To evaluate the influence of tumour size on diagnostic accuracy and the use of maximum standardized uptake value (SUV{sub MAX}) thresholds to differentiate malignant from benign breast lesions. A total of 172 consecutive patients with an imaging abnormality were included in this IRB-approved prospective study. All patients underwent {sup 18}F-FDG PET/CT and CE-MRI of the breast at 3 T in the prone position. Two reader teams independently evaluated the likelihood of malignancy as determined by {sup 18}F-FDG PET/CT and CE-MRI independently. {sup 18}F-FDG PET/CT data were qualitatively evaluated by visual interpretation. Quantitative assessment was performed by calculation of SUV{sub MAX}. Sensitivity, specificity, diagnostic accuracy, area under the curve and interreader agreement were calculated for all lesions and for lesions <10 mm. Histopathology was used as the standard of reference. There were 132 malignant and 40 benign lesions; 23 lesions (13.4 %) were <10 mm. Both {sup 18}F-FDG PET/CT and CE-MRI achieved an overall diagnostic accuracy of 93 %. There were no significant differences in sensitivity (p = 0.125), specificity (p = 0.344) or diagnostic accuracy (p = 1). For lesions <10 mm, diagnostic accuracy deteriorated to 91 % with both {sup 18}F-FDG PET/CT and CE-MRI. Although no significant difference was found for lesions <10 mm, CE-MRI at 3 T seemed to be more sensitive but less specific than {sup 18}F-FDG PET/CT. Interreader agreement was excellent (κ = 0.85 and κ = 0.92). SUV{sub MAX} threshold was not helpful in differentiating benign from malignant lesions. {sup 18}F-FDG PET/CT and CE-MRI at 3 T showed equal diagnostic accuracies in breast cancer diagnosis. For lesions <10 mm, diagnostic accuracy deteriorated, but was equal for {sup 18}F-FDG PET/CT and CE-MRI at 3 T. For lesions <10 mm, CE-MRI at 3 T seemed

  13. 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

  14. The effectiveness and cost-effectiveness of intraoperative imaging in high-grade glioma resection; a comparative review of intraoperative ALA, fluorescein, ultrasound and MRI.

    Science.gov (United States)

    Eljamel, M Sam; Mahboob, Syed Osama

    2016-12-01

    Surgical resection of high-grade gliomas (HGG) is standard therapy because it imparts significant progression free (PFS) and overall survival (OS). However, HGG-tumor margins are indistinguishable from normal brain during surgery. Hence intraoperative technology such as fluorescence (ALA, fluorescein) and intraoperative ultrasound (IoUS) and MRI (IoMRI) has been deployed. This study compares the effectiveness and cost-effectiveness of these technologies. Critical literature review and meta-analyses, using MEDLINE/PubMed service. The list of references in each article was double-checked for any missing references. We included all studies that reported the use of ALA, fluorescein (FLCN), IoUS or IoMRI to guide HGG-surgery. The meta-analyses were conducted according to statistical heterogeneity between studies. If there was no heterogeneity, fixed effects model was used; otherwise, a random effects model was used. Statistical heterogeneity was explored by χ 2 and inconsistency (I 2 ) statistics. To assess cost-effectiveness, we calculated the incremental cost per quality-adjusted life-year (QALY). Gross total resection (GTR) after ALA, FLCN, IoUS and IoMRI was 69.1%, 84.4%, 73.4% and 70% respectively. The differences were not statistically significant. All four techniques led to significant prolongation of PFS and tended to prolong OS. However none of these technologies led to significant prolongation of OS compared to controls. The cost/QALY was $16,218, $3181, $6049 and $32,954 for ALA, FLCN, IoUS and IoMRI respectively. ALA, FLCN, IoUS and IoMRI significantly improve GTR and PFS of HGG. Their incremental cost was below the threshold for cost-effectiveness of HGG-therapy, denoting that each intraoperative technology was cost-effective on its own. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. 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.

  16. Multi-frequency bioelectrical impedance analysis (BIA) compared to magnetic resonance imaging (MRI) for estimation of fat-free mass in colorectal cancer patients treated with chemotherapy

    DEFF Research Database (Denmark)

    Palle, Stine Skov; Tang Møllehave, Line; Kadkhoda, Zahra Taheri

    2016-01-01

    during the course of their treatments. Objective: To examine relationships between single cross-sectional thighs magnetic resonance imaging (MRI), skeletal muscle mass (SM) as reference and multi-frequency bioelectrical impedance analysis (BIA) fat free mass (FFM) in patients with colorectal cancer...... undergoing chemotherapy. Design: In an observational, prospective study we examine the relationships between single cross-sectional thighs MRI (T1-weighted (1.5 T) SM compared to FFM BIA (8-electrodes multi-frequency Tanita MC780MA)) and FFM skin-fold thickness (ST) (4-points (Harpenden, Skinfold Caliper......)) and SM equation for non-obese persons from Lee et al. 2000 (L2000) (based on age, height, weight, sex and race). FFM and SM (kg) were calculated based on either area (MRI) or weight. Results: 18 CRC patients (10 males and 8 females) with mean (SD) age 67 yr (6) were measured at baseline, and 13 were...

  17. 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.

  18. 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

  19. 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.)

  20. 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.)

  1. 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.)

  2. 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.)

  3. 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.)

  4. 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.

  5. Estudo comparativo por ressonância magnética de púbis entre atletas e sedentários assintomáticos Comparative study between the pubis of asymptomatic athletes and non-athletes with MRI

    Directory of Open Access Journals (Sweden)

    Rodrigo Castelo Branco

    2010-01-01

    population studied. CONCLUSION: Professional soccer players are at a higher risk for developing changes in the pubic region, evidenced in magnetic resonance images, when compared to non-athletes. Those findings are not necessarily related to groin pain, and are probably related to intense stress.

  6. Pancreatic gross tumor volume contouring on computed tomography (CT) compared with magnetic resonance imaging (MRI): Results of an international contouring conference.

    Science.gov (United States)

    Hall, William A; Heerkens, Hanne D; Paulson, Eric S; Meijer, Gert J; Kotte, Alexis N; Knechtges, Paul; Parikh, Parag J; Bassetti, Michael F; Lee, Percy; Aitken, Katharine L; Palta, Manisha; Myrehaug, Sten; Koay, Eugene J; Portelance, Lorraine; Ben-Josef, Edgar; Erickson, Beth A

    Accurate identification of the gross tumor volume (GTV) in pancreatic adenocarcinoma is challenging. We sought to understand differences in GTV delineation using pancreatic computed tomography (CT) compared with magnetic resonance imaging (MRI). Twelve attending radiation oncologists were convened for an international contouring symposium. All participants had a clinical and research interest in pancreatic adenocarcinoma. CT and MRI scans from 3 pancreatic cases were used for contouring. CT and MRI GTVs were analyzed and compared. Interobserver variability was compared using Dice's similarity coefficient (DSC), Hausdorff distances, and Jaccard indices. Mann-Whitney tests were used to check for significant differences. Consensus contours on CT and MRI scans and constructed count maps were used to visualize the agreement. Agreement regarding the optimal method to determine GTV definition using MRI was reached. Six contour sets (3 from CT and 3 from MRI) were obtained and compared for each observer, totaling 72 contour sets. The mean volume of contours on CT was significantly larger at 57.48 mL compared with a mean of 45.76 mL on MRI, P = .011. The standard deviation obtained from the CT contours was significantly larger than the standard deviation from the MRI contours (P = .027). The mean DSC was 0.73 for the CT and 0.72 for the MRI (P = .889). The conformity index measurement was similar for CT and MRI (P = .58). Count maps were created to highlight differences in the contours from CT and MRI. Using MRI as a primary image set to define a pancreatic adenocarcinoma GTV resulted in smaller contours compared with CT. No differences in DSC or the conformity index were seen between MRI and CT. A stepwise method is recommended as an approach to contour a pancreatic GTV using MRI. Copyright © 2017 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  7. The value of intraoperative ultrasound (IUS) examination for the visualization of metastatic cerebral lesions, compared with computed tomography (CT) and magnetic resonance (MRI)

    International Nuclear Information System (INIS)

    Tacikowska, M.; Szczerbicki, M.; Grzesiakowska, U.

    2001-01-01

    The purpose of this study is: 1. to assess the value of intraoperative ultrasonographic examination (IUSG) in confirming intraoperatively the presence of metastatic tumours detected preoperatively by computed tomography (CT) and magnetic resonance tomography (MRI), 2. to evaluate an accordance of the numbers, localization and dimensions of metastatic tumours recognized preoperatively (CT and MRI) with those shown by intraoperative USG, 3. to comparatively assess the images of metastatic tumours found in preoperative CT and MRI examinations and in intraoperative USG examinations. Sixteen patients were operated upon for metastatic intracranial tumours from various primary foci. All patients had diagnostic brain examinations before the operation: MRI and CT in 7 cases, only MRI in 3 cases, only CT in 6 cases. Intraoperative USG examination was done in all cases. Retrospective analysis included: 1. comparative assessment of the images of metastatic tumours in intraoperative USG versus preoperative MRI and CT findings, 2. analysis of the number, localization and dimensions of metastatic tumours detected preoperatively and in intraoperative USG examination. The comparison of the greatest dimensions of metastatic lesions measured in CT and MRI findings, and in intraoperative USG based on Student t test showed no statistically significant differences between the examinations performed, p=0.2449. No statistically significant difference were found either between the numbers of metastatic lesions detected by these methods, p=0.71830. In the analysis of the images of metastatic lesions in preoperative examinations, the non--homogenous foci with margin enhancement after administration of gadolinium or contrast medium, with inner area not enhanced (necrosis?) were found in 8 cases (10 foci lesions), and in USG in 6 cases (9 focal lesions). In one case (one lesion) USG showed that the tumour was hypo echogenic as a whole, without areola around it. Intraoperative USG examination

  8. 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.

  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. 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.

  11. 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

  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. 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)

  14. 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.

  15. 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.

  16. 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...

  17. 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.

  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

    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

  19. 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

  20. 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

  1. Comparative evaluation of chest radiography, low-field MRI, the Shwachman-Kulczycki score and pulmonary function tests in patients with cystic fibrosis

    International Nuclear Information System (INIS)

    Anjorin, Angela; Vogl, Thomas J.; Schmidt, Helga; Posselt, Hans-Georg; Smaczny, Christina; Ackermann, Hanns; Deimling, Michael; Abolmaali, Nasreddin

    2008-01-01

    The aim of this study was to investigate whether the parenchymal lung damage in patients suffering from cystic fibrosis (CF) can be equivalently quantified by the Chrispin-Norman (CN) scores determined with low-field magnetic resonance imaging (MRI) and conventional chest radiography (CXR). Both scores were correlated with pulmonary function tests (PFT) and the Shwachman-Kulczycki method (SKM). To evaluate the comparability of MRI and CXR for different states of the disease, all scores were applied to patients divided into three age groups. Seventy-three CF patients (mean SKM score: 62 ± 8) with a median age (range) of 14 years (7-32) were included. The mean CN scores determined with both imaging methods were comparable (CXR: 12.1 ± 4.7; MRI: 12.0 ± 4.5) and showed high correlation (P < 0.05, R = 0.97). Only weak correlations were found between imaging, PFT, and SKM. Both imaging modalities revealed significantly more severe disease expression with age, while PFT and SKM failed to detect early signs of disease. We conclude that imaging of the lung in CF patients is capable of detecting subtle and early parenchymal destruction before lung function or clinical scoring is affected. Furthermore, low-field MRI revealed high consistency with chest radiography and may be used for a thorough follow-up while avoiding radiation exposure. (orig.)

  2. 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)

  3. Comparative brain stem lesions on MRI of acute disseminated encephalomyelitis, neuromyelitis optica, and multiple sclerosis.

    Directory of Open Access Journals (Sweden)

    Zhengqi Lu

    Full Text Available BACKGROUND: Brain stem lesions are common in patients with acute disseminated encephalomyelitis (ADEM, neuromyelitis optica (NMO, and multiple sclerosis (MS. OBJECTIVES: To investigate comparative brain stem lesions on magnetic resonance imaging (MRI among adult patients with ADEM, NMO, and MS. METHODS: Sixty-five adult patients with ADEM (n = 17, NMO (n = 23, and MS (n = 25 who had brain stem lesions on MRI were enrolled. Morphological features of brain stem lesions among these diseases were assessed. RESULTS: Patients with ADEM had a higher frequency of midbrain lesions than did patients with NMO (94.1% vs. 17.4%, P<0.001 and MS (94.1% vs. 40.0%, P<0.001; patients with NMO had a lower frequency of pons lesions than did patients with MS (34.8% vs. 84.0%, P<0.001 and ADEM (34.8% vs. 70.6%, P = 0.025; and patients with NMO had a higher frequency of medulla oblongata lesions than did patients with ADEM (91.3% vs. 35.3%, P<0.001 and MS (91.3% vs. 36.0%, P<0.001. On the axial section of the brain stem, the majority (82.4% of patients with ADEM showed lesions on the ventral part; the brain stem lesions in patients with NMO were typically located in the dorsal part (91.3%; and lesions in patients with MS were found in both the ventral (44.0% and dorsal (56.0% parts. The lesions in patients with ADEM (100% and NMO (91.3% had poorly defined margins, while lesions of patients with MS (76.0% had well defined margins. Brain stem lesions in patients with ADEM were usually bilateral and symmetrical (82.4%, while lesions in patients with NMO (87.0% and MS (92.0% were asymmetrical or unilateral. CONCLUSIONS: Brain stem lesions showed various morphological features among adult patients with ADEM, NMO, and MS. The different lesion locations may be helpful in distinguishing these diseases.

  4. Femoroacetabular cam-type impingement: Diagnostic sensitivity and specificity of radiographic views compared to radial MRI

    International Nuclear Information System (INIS)

    Domayer, S.E.; Ziebarth, K.; Chan, J.; Bixby, S.; Mamisch, T.C.; Kim, Y.J.

    2011-01-01

    Purpose: To retrospectively assess the diagnostic sensitivity of 45° Dunn view and cross-table lateral radiographs for the assessment of cam deformity by comparison with radial MRI. Materials and methods: 60 cases with radiographs (38 a–p and 45° Dunn views, 22 a–p and cross-table lateral views) and radial MRI were assessed. Alpha angle measurements were obtained both for radiographs and radial MRI. Statistics included frequency analysis, bivariate linear correlation analyses of MRI and radiograph measurements and cross-table analyses testing for the sensitivity and specificity of radiographs for the detection of an alpha angle larger than 55°. Results: 53.3% had the maximum alpha angle in the superior–anterior aspect of the femoral head–neck junction. Cam deformity was found in 45/60 cases (75%) in radial MRI. Pearson correlation demonstrated the Dunn view was most accurate for the superior–anterior aspect (.772, P < .001). The cross-table lateral views were best suited for the anterior–superior aspect (.511, P < .05). The sensitivity for cam deformity in the Dunn view was 96.4% vs. 70.6% in the cross-table lateral view. Conclusion: The 45° Dunn view can improve the first line of impingement diagnostics. Radial MRI however remains indispensable for pre-operative planning and the evaluation of symptomatic cases without obvious deformity.

  5. Study of tonotopic brain changes with functional MRI and FDG-PET in a patient with unilateral objective cochlear tinnitus.

    Science.gov (United States)

    Guinchard, A-C; Ghazaleh, Naghmeh; Saenz, M; Fornari, E; Prior, J O; Maeder, P; Adib, S; Maire, R

    2016-11-01

    We studied possible brain changes with functional MRI (fMRI) and fluorodeoxyglucose positron emission tomography (FDG-PET) in a patient with a rare, high-intensity "objective tinnitus" (high-level SOAEs) in the left ear of 10 years duration, with no associated hearing loss. This is the first case of objective cochlear tinnitus to be investigated with functional neuroimaging. The objective cochlear tinnitus was measured by Spontaneous Otoacoustic Emissions (SOAE) equipment (frequency 9689 Hz, intensity 57 dB SPL) and is clearly audible to anyone standing near the patient. Functional modifications in primary auditory areas and other brain regions were evaluated using 3T and 7T fMRI and FDG-PET. In the fMRI evaluations, a saturation of the auditory cortex at the tinnitus frequency was observed, but the global cortical tonotopic organization remained intact when compared to the results of fMRI of healthy subjects. The FDG-PET showed no evidence of an increase or decrease of activity in the auditory cortices or in the limbic system as compared to normal subjects. In this patient with high-intensity objective cochlear tinnitus, fMRI and FDG-PET showed no significant brain reorganization in auditory areas and/or in the limbic system, as reported in the literature in patients with chronic subjective tinnitus. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Different activation of opercular and posterior cingulate cortex (PCC) in patients with complex regional pain syndrome (CRPS I) compared with healthy controls during perception of electrically induced pain: a functional MRI study.

    Science.gov (United States)

    Freund, Wolfgang; Wunderlich, Arthur P; Stuber, Gregor; Mayer, Florian; Steffen, Peter; Mentzel, Martin; Weber, Frank; Schmitz, Bernd

    2010-05-01

    Although the etiology of complex regional pain syndrome type 1 (CRPS 1) is still debated, many arguments favor central maladaptive changes in pain processing as an important causative factor. To look for the suspected alterations, 10 patients with CRPS affecting the left hand were explored with functional magnetic resonance imaging during graded electrical painful stimulation of both hands subsequently and compared with healthy participants. Activation of the anterior insula, posterior cingulate cortex (PCC), and caudate nucleus was seen in patients during painful stimulation. Compared with controls, CRPS patients had stronger activation of the PCC during painful stimulation of the symptomatic hand. The comparison of insular/opercular activation between controls and patients with CRPS I during painful stimulation showed stronger (posterior) opercular activation in controls than in patients. Stronger PCC activation during painful stimulation may be interpreted as a correlate of motor inhibition during painful stimuli different from controls. Also, the decreased opercular activation in CRPS patients shows less sensory-discriminative processing of painful stimuli.These results show that changed cerebral pain processing in CRPS patients is less sensory-discriminative but more motor inhibition during painful stimuli. These changes are not limited to the diseased side but show generalized alterations of cerebral pain processing in chronic pain patients.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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)

  12. 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)

  13. 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

  14. 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.

  15. A Method for Manufacturing Oncological Phantoms for the Quantification of 18F-FDG PET and DW-MRI Studies

    Directory of Open Access Journals (Sweden)

    Francesca Gallivanone

    2017-01-01

    Full Text Available The aim of this work was to develop a method to manufacture oncological phantoms for quantitation purposes in 18F-FDG PET and DW-MRI studies. Radioactive and diffusion materials were prepared using a mixture of agarose and sucrose radioactive gels. T2 relaxation and diffusion properties of gels at different sucrose concentrations were evaluated. Realistic oncological lesions were created using 3D-printed plastic molds filled with the gel mixture. Once solidified, gels were extracted from molds and immersed in a low-radioactivity gel simulating normal background tissue. A breast cancer phantom was manufactured using the proposed method as an exploratory feasibility study, including several realistic oncological configurations in terms of both radioactivity and diffusion. The phantom was acquired in PET with 18F-FDG, immediately after solidification, and in DW-MRI the following day. Functional volumes characterizing the simulated BC lesions were segmented from PET and DW-MRI images. Measured radioactive uptake and ADC values were compared with gold standards. Phantom preparation was straightforward, and the time schedule was compatible with both PET and MRI measurements. Lesions appeared on 18F-FDG PET and DW-MRI images as expected, without visible artifacts. Lesion functional parameters revealed the phantom’s potential for validating quantification methods, in particular for new generation hybrid PET-MRI systems.

  16. Assessing hepatic fibrosis: comparing the intravoxel incoherent motion in MRI with acoustic radiation force impulse imaging in US

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chih-Horng; Liang, Po-Chin; Shih, Tiffany Ting-Fang [National Taiwan University Hospital, Department of Medical Imaging, Taipei (China); National Taiwan University College of Medicine, Department of Radiology, Taipei (China); Ho, Ming-Chih; Hu, Rey-Heng; Lai, Hong-Shiee [National Taiwan University Hospital and College of Medicine, Department of Surgery, Taipei (China); Jeng, Yung-Ming [National Taiwan University Hospital and College of Medicine, Department of Pathology, Taipei (China)

    2015-12-15

    This study compared the diagnostic performance of intravoxel incoherent motion (IVIM) in magnetic resonance imaging (MRI) and acoustic radiation force impulse imaging (ARFI) in ultrasound (US) for liver fibrosis (LF) evaluation. A total of 49 patients scheduled for liver surgery were recruited. LF in the non-tumorous liver parenchyma at the right lobe was estimated using a slow diffusion coefficient, fast diffusion coefficient (D{sub fast}), perfusion fraction (f) of the IVIM parameters, the total apparent diffusion coefficient of conventional diffusion-weighted imaging and the shear wave velocity (Vs) of ARFI. LF was graded using the Metavir scoring system on histological examination. The Spearman rank correlation coefficient for correlation and analysis of variance was used for determining difference. The diagnostic performance was compared using receiver operating characteristic curve analysis. LF exhibited significant correlation with the three parameters D{sub fast}, f, and Vs (r = -0.528, -0.337, and 0.481, respectively, P < 0.05). The D{sub fast} values in the F4 group were significantly lower than those in the F0, F1 and F2 groups. D{sub fast} exhibited a non-inferior performance for diagnosing all fibrosis grades compared with that of Vs. Both IVIM and ARFI provide reliable estimations for the noninvasive assessment of LF. (orig.)

  17. Brain cortical structural differences between non-central nervous system cancer patients treated with and without chemotherapy compared to non-cancer controls: a cross-sectional pilot MRI study using clinically indicated scans

    Science.gov (United States)

    Shiroishi, Mark S.; Gupta, Vikash; Bigjahan, Bavrina; Cen, Steven Y.; Rashid, Faisal; Hwang, Darryl H.; Lerner, Alexander; Boyko, Orest B.; Liu, Chia-Shang Jason; Law, Meng; Thompson, Paul M.; Jahanshad, Neda

    2017-11-01

    Background: Increases in cancer survival have made understanding the basis of cancer-related cognitive impairment (CRCI) more important. CRCI neuroimaging studies have traditionally used dedicated research brain MRIs in breast cancer survivors with small sample sizes; little is known about other non-CNS cancers. However, there is a wealth of unused data from clinically-indicated MRIs that could be used to study CRCI. Objective: Evaluate brain cortical structural differences in those with non-CNS cancers using clinically-indicated MRIs. Design: Cross-sectional Patients: Adult non-CNS cancer and non-cancer control (C) patients who underwent clinically-indicated MRIs. Methods: Brain cortical surface area and thickness were measured using 3D T1-weighted images. An age-adjusted linear regression model was used and the Benjamini and Hochberg false discovery rate (FDR) corrected for multiple comparisons. Group comparisons were: cancer cases with chemotherapy (Ch+), cancer cases without chemotherapy (Ch-) and subgroup of lung cancer cases with and without chemotherapy vs C. Results: Sixty-four subjects were analyzed: 22 Ch+, 23 Ch- and 19 C patients. Subgroup analysis of 16 LCa was also performed. Statistically significant decreases in either cortical surface area or thickness were found in multiple ROIs primarily within the frontal and temporal lobes for all comparisons. Limitations: Several limitations were apparent including a small sample size that precluded adjustment for other covariates. Conclusions: Our preliminary results suggest that various types of non-CNS cancers, both with and without chemotherapy, may result in brain structural abnormalities. Also, there is a wealth of untapped clinical MRIs that could be used for future CRCI studies.

  18. 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)

  19. Prenatal ultrasound and fetal MRI: the comparative value of each modality in prenatal diagnosis.

    Science.gov (United States)

    Pugash, Denise; Brugger, Peter C; Bettelheim, Dieter; Prayer, Daniela

    2008-11-01

    Fetal MRI is used with increasing frequency as an adjunct to ultrasound (US) in prenatal diagnosis. In this review, we discuss the relative value of both prenatal US and MRI in evaluating fetal and extra-fetal structures for a variety of clinical indications. Advantages and disadvantages of each imaging modality are addressed. In summary, MRI has advantages in demonstrating pathology of the brain, lungs, complex syndromes, and conditions associated with reduction of amniotic fluid. At present, US is the imaging method of choice during the first trimester, and in the diagnosis of cardiovascular abnormalities, as well as for screening. In some conditions, such as late gestational age, increased maternal body mass index, skeletal dysplasia, and metabolic disease, neither imaging method may provide sufficient diagnostic information.

  20. Prenatal ultrasound and fetal MRI: The comparative value of each modality in prenatal diagnosis

    International Nuclear Information System (INIS)

    Pugash, Denise; Brugger, Peter C.; Bettelheim, Dieter; Prayer, Daniela

    2008-01-01

    Fetal MRI is used with increasing frequency as an adjunct to ultrasound (US) in prenatal diagnosis. In this review, we discuss the relative value of both prenatal US and MRI in evaluating fetal and extra-fetal structures for a variety of clinical indications. Advantages and disadvantages of each imaging modality are addressed. In summary, MRI has advantages in demonstrating pathology of the brain, lungs, complex syndromes, and conditions associated with reduction of amniotic fluid. At present, US is the imaging method of choice during the first trimester, and in the diagnosis of cardiovascular abnormalities, as well as for screening. In some conditions, such as late gestational age, increased maternal body mass index, skeletal dysplasia, and metabolic disease, neither imaging method may provide sufficient diagnostic information

  1. Prenatal ultrasound and fetal MRI: The comparative value of each modality in prenatal diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Pugash, Denise [Department of Radiology, University of British Columbia, Vancouver (Canada)], E-mail: dpugash@cw.bc.ca; Brugger, Peter C. [Integrative Morphology Group, Centre of Anatomy and Cell Biology, Medical University of Vienna, Waehringerstrasse 13, 1090 Vienna (Austria); Bettelheim, Dieter [University Clinics of Obstetrics and Gynaecology, Medical University of Vienna, Waehringerguertel 18-20, 1090 Wien (Austria); Prayer, Daniela [University Clinics of Radiodiagnostics, Medical University of Vienna, Waehringerguertel 18-20, 1090 Wien (Austria)

    2008-11-15

    Fetal MRI is used with increasing frequency as an adjunct to ultrasound (US) in prenatal diagnosis. In this review, we discuss the relative value of both prenatal US and MRI in evaluating fetal and extra-fetal structures for a variety of clinical indications. Advantages and disadvantages of each imaging modality are addressed. In summary, MRI has advantages in demonstrating pathology of the brain, lungs, complex syndromes, and conditions associated with reduction of amniotic fluid. At present, US is the imaging method of choice during the first trimester, and in the diagnosis of cardiovascular abnormalities, as well as for screening. In some conditions, such as late gestational age, increased maternal body mass index, skeletal dysplasia, and metabolic disease, neither imaging method may provide sufficient diagnostic information.

  2. SPECT/CT versus MRI in patients with nonspecific pain of the hand and wrist - a pilot study

    International Nuclear Information System (INIS)

    Huellner, Martin W.; Buerkert, Alexander; Schleich, Florian S.; Strobel, Klaus; Veit-Haibach, Patrick; Schuerch, Maja; Hug, Urs; Wartburg, Urs von

    2012-01-01

    Hand and wrist pain is a diagnostic challenge for hand surgeons and radiologists due to the complex anatomy of the involved small structures. The American College of Radiology recommends MRI as the study of choice in patients with chronic wrist pain if radiographs are negative. Lately, state-of-the-art SPECT/CT systems have been introduced and may help in the diagnosis of this selected indication. This retrospective study included 21 patients with nonspecific pain of the hand/wrist. The diagnosis of nonspecific wrist pain was made by the referring hand surgeon based on patient history, clinical examination, plain radiography and clinical guidelines. All patients received planar early-phase imaging and late-phase SPECT/CT imaging as well as MRI. Lesions were divided into major (causative) and minor (not causative) pathologies according to clinical follow-up. Furthermore, oedema-like bone marrow changes seen on MRI were compared with focally increased tracer uptake seen on SPECT/CT images. MRI yielded a quite high sensitivity (0.86), but a low specificity (0.20). In contrast, SPECT/CT yielded a high specificity (1.00) and a low sensitivity (0.71). Oedema-like bone marrow changes were detected in 15 lesions in 11 patients. In ten lesions with bone marrow oedema on MRI, foci of elevated tracer uptake were detected on SPECT/CT. Overall, MRI was more sensitive, but SPECT/CT was more specific in the evaluation of causative pathologies. In this initial comparison, SPECT/CT showed higher specificity than MRI in the evaluation of causative pathologies in patients with nonspecific wrist pain. However, MRI was more sensitive. Thus, SPECT/CT was shown to be a useful problem-solving tool in the diagnostic work-up of these patients. (orig.)

  3. A Prospective Study Comparing 99mTc-Hydroxyethylene-Diphosphonate Planar Bone Scintigraphy and Whole-Body SPECT/CT with 18F-Fluoride PET/CT and 18F-Fluoride PET/MRI for Diagnosing Bone Metastases

    DEFF Research Database (Denmark)

    Löfgren, Johan; Mortensen, Jann; Rasmussen, Sine H

    2017-01-01

    proven malignancy referred for clinical pBS were prospectively enrolled. pBS and whole-body SPECT/CT were performed followed by18F-NaF PET/CT within 9 d.18F-NaF PET/MRI was also performed in 46 patients.Results:Bone metastases were confirmed in 16 patients and excluded in 101, which was lower than......-NaF PET/CT, and PET/MRI detected additional lesions compared with pBS in 31%, 63%, and 71%, respectively.Conclusion:18F-NaF PET/CT and whole-body SPECT/CT resulted in a significant reduction of equivocal readings compared with pBS, which implies an improved diagnostic confidence. However, the clinical...

  4. MRI in patients with chronic pubalgia: Is precise useful information provided to the surgeon? A case-control study.

    Science.gov (United States)

    Larbi, A; Pesquer, L; Reboul, G; Omoumi, P; Perozziello, A; Abadie, P; Loriaut, P; Copin, P; Ducouret, E; Dallaudière, B

    2016-10-01

    Recent studies described that MRI is a good examination to assess damage in chronic athletic pubalgia (AP). However, to our knowledge, no studies focus on systematic correlation of precise tendon or parietal lesion in MRI with surgery and histological assessment. Therefore, we performed a case-control study to determine if MRI can precisely assess Adductor longus (AL) tendinopathy and parietal lesion, compared with surgery and histology. MRI can determine if AP comes from pubis symphysis, musculotendinous or inguinal orifice structures. Eighteen consecutive patients were enrolled from November 2011 to April 2013 for chronic AP. To constitute a control group, we also enrolled 18 asymptomatic men. All MRI were reviewed in consensus by 2 skeletal radiologists for pubic symphysis, musculotendinous, abdominal wall assessment and compared to surgery and histology findings. Regarding pubis symphysis, we found 4 symmetric bone marrow oedema (14%), 2 secondary cleft (7%) and 2 superior ligaments lesions (7%). For AL tendon, we mainly found 13 asymmetric bone marrow oedema (46%), 15 hyperaemia (54%). Regarding abdominal wall, the deep inguinal orifice size in the group of symptomatic athletes and the control group was respectively 27.3±6.4mm and 23.8±6.3mm. The correlation between MRI and surgery/histology was low: 20% for the AL tendon and 9% for the abdominal wall. If we chose the criteria "affected versus unaffected", this correlation became higher: 100% for AL tendon and 73% for the abdominal wall. MRI chronic athletic pubalgia concerns preferentially AL tendinopathy and deep inguinal canal dehiscence with high correlation to surgery/histology when only considering the item "affected versus unaffected" despite low correlation when we try to precisely grade these lesions. III: case-control study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. Dynamic contrast-enhanced breast MRI at 7T and 3T : an intra-individual comparison study

    NARCIS (Netherlands)

    de Lima Gomes de Menezes, G; Stehouwer, Bertine L; Klomp, DWJ; van der Velden, Tijl A; van den Bosch, Maurice A A J; Knuttel, Floor; Boer, VO; van der Kemp, Wybe J M; Luijten, Peter R; Veldhuis, Wouter B.

    2016-01-01

    The aim of this study is to compare the current state of lesion identification, the BI-RADS classification and the contrast-enhancement behavior at 7T and 3T breast MRI in the same patient group. Twenty-seven patients with thirty suspicious lesions were selected for this prospective study and

  6. 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.

  7. 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.

  8. Cerebral MRI of very low birth weight children at 6 years of age compared with the findings at 1 year

    International Nuclear Information System (INIS)

    Skranes, J.S.; Nilsen, G.; Smevik, O.; Vik, T.; Brubakk, A.M.

    1998-01-01

    Background. We have previously reported the results of cerebral MRI examinations in an unselected year cohort of very low birth weight (VLBW) infants at one year of corrected age. Twenty-one (78 %) of 27 infants had abnormal myelination, mainly in the central occipital white matter (COWM) and in the centrum semiovale (CS), seen on T2-weighted images. Twelve infants had irregular and dilated lateral ventricles. We speculated whether these findings indicated perinatal periventricular leukomalacia (PVL). Only two infants had completely normal MRI at age 1 year. Objective. To determine whether the abnormal myelination seen at 1 year of age, was still present, either as delayed myelination or as gliosis caused by perinatal PVL. Materials and methods. In the present study, we report the results of follow-up cerebral MRI in 20 of these infants at 6 years of age. Results. Most of the children with MRI deviations at 1 year still had abnormalities at 6 years. Abnormal myelination in the central occipital white matter combined with abnormalities in the CS or with ventricular dilatation at age 1 year, presented as gliosis in 12 of 13 children at 6 years of age. Abnormalities solely in the COWM at age 1 year had normalised in two of five children and persisted as delayed myelination in three at age 6 years. Gliotic changes in periventricular white matter were found in 12 of 20 children (60 %). Areas most affected were the CS (11 children) and the COWM (9 children). Delayed myelination in COWM was found in six children (30 %), combined with gliosis in CS in three children. Twelve infants had ventricular dilatation both at 1 and 6 years of age. Conclusions. The MRI correlates of PVL, i. e. gliosis and ventricular dilatation, are common findings on cerebral MRI at 6 years of age in VLBW infants. (orig.)

  9. {sup 18}F{sub F}DG PET in evaluating malignancies compared with CT, MRI and pathology in 58 cases

    Energy Technology Data Exchange (ETDEWEB)

    Li, L. [Air Force General Hospital, Beijing (Switzerland)

    2000-07-01

    This article discussed the practical application of {sup 18}F-FDG PET imaging techniques to depict, state, or define recurrences for five important malignancies: lung cancer, colorectal and head-and-neck cancer, intracranial malignant glioma and primary or secondary hepatic malignant diseases. And comparisons of {sup 18}F-FDG PET with CT, MRI imaging were addressed specifically. We reviewed our initial experience with 48 malignant and ten non-malignant cases. Among malignant group, 36 cases were confirmed by operation or biopsy, Other ten non-malignant diseases, including brain infarction, post-radiotherapy necrosis or scar and lung abscesses were followed with CT or MRI at least 6 months. All patients received intravenous administration of {sup 18}F-FDG 10-15 mCi, followed by a 40 minutes uptake phase, and subsequent imaged using a Siemens ECAT 931 whole-body scanner with resolution of 4 mm FWHM in the center of the field of view. Filtered back projection reconstruction was used to display attenuated or non-attenuated corrected images. The result of {sup 18}F-FDG PET was retrospectively evaluated to assess the degree of uptake of {sup 18}F-FDG PET in the tumor tissues and compared with CT, MRI and pathology. CT and MRI exam were taken before or after PET study in two weeks. {sup 18}F-FDG PET scans showed a significantly increased FDG metabolism in 47 malignant lesions, The tumor / normal tissue FDG uptake rate were 4.16 {+-}2.11. In 47 cases with neoplasm, {sup 18}F-FDG PET findings were constant with or further confirmed the CT or MRI diagnosis in 35/47 (74.5%) and 12/47 (253%) cases. Another one small intracranial metastasis (<0,6cm), shown on contrast MRI was not displayed by glucose metabolism Otherwise, the tumor/normal tissue FDG uptake rate were 0.86 {+-} 1,46 in ten non-malignant cases. Most of post-radiotherapy cerebral necrosis, which can't be distinguished on both contrast CT and MRI, showed FDG uptake defect. One cerebral infarction, previously

  10. Are There Multiple Kinds of Episodic Memory? An fMRI Investigation Comparing Autobiographical and Recognition Memory Tasks.

    Science.gov (United States)

    Chen, Hung-Yu; Gilmore, Adrian W; Nelson, Steven M; McDermott, Kathleen B

    2017-03-08

    What brain regions underlie retrieval from episodic memory? The bulk of research addressing this question with fMRI has relied upon recognition memory for materials encoded within the laboratory. Another, less dominant tradition has used autobiographical methods, whereby people recall events from their lifetime, often after being cued with words or pictures. The current study addresses how the neural substrates of successful memory retrieval differed as a function of the targeted memory when the experimental parameters were held constant in the two conditions (except for instructions). Human participants studied a set of scenes and then took two types of memory test while undergoing fMRI scanning. In one condition (the picture memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it was recollected from the prior study episode. In a second condition (the life memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it reminded them of a specific event from their preexperimental lifetime. An examination of successful retrieval (yes responses) for recently studied scenes for the two test types revealed pronounced differences; that is, autobiographical retrieval instantiated with the life memory test preferentially activated the default mode network, whereas hits in the picture memory test preferentially engaged the parietal memory network as well as portions of the frontoparietal control network. When experimental cueing parameters are held constant, the neural underpinnings of successful memory retrieval differ when remembering life events and recently learned events. SIGNIFICANCE STATEMENT Episodic memory is often discussed as a solitary construct. However, experimental traditions examining episodic memory use very different approaches, and these are rarely compared to one another. When the neural correlates associated with each approach have been directly contrasted, results have varied considerably

  11. 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)

  12. Study of Frequency of Low Back Pain and Lumbar Disc Herniation in Patients of Hamadan MRI Center in 2002

    Directory of Open Access Journals (Sweden)

    M. Jabbari

    2004-07-01

    Full Text Available Low back pain is one of the prevalent diseases of the world. In this research, with helping of MRI the incidence of disc herniation in patients of low back pain in our living area was studied. Survey of the specifications of disc herniation was carried out and data was compared with some performed studies in other parts of the world. In this study, for 600 patients referred to HAMEDAN MRI CENTER, who had complaint of low back pain, MRI study was performed. Then, MRI Images of the patients who had disc hernition, studied for number, form, severity and anatomic position of the herniated disc and family history of low back pain. 83.7% of the studied cases was pathologic and 16.3% was normal. Among the pathologic cases, 70.12% had disc herniation. The most common age group in both sex for disc herniotion was 30-50 years. Disc herniation in men was more common than women. The most common anatomic position of the herniated disc was L4- L5 disc, mostly was one herniated disc and centrolateral form. There was not any meaningful relation between family history of the low back pain and lumbar disc herniation. This study showed that lumbar disc herniation is one of the common causes of the low back pain in our living area and MRI is the choice imaging modality for diagnosis and survey of low back pain and disc herniation.

  13. 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

  14. Comparison of a fast 5-min knee MRI protocol with a standard knee MRI protocol. A multi-institutional multi-reader study

    Energy Technology Data Exchange (ETDEWEB)

    FitzGerald Alaia, Erin; Beltran, Luis S.; Garwood, Elisabeth; Burke, Christopher J.; Gyftopoulos, Soterios [NYU Langone Medical Center, Department of Radiology, Musculoskeletal Division, New York, NY (United States); Benedick, Alex [Case Western Reserve University, School of Medicine, Cleveland, OH (United States); Obuchowski, Nancy A. [Cleveland Clinic, Department of Quantitative Health Sciences, Cleveland, OH (United States); Polster, Joshua M.; Schils, Jean; Subhas, Naveen [Cleveland Clinic, Department of Radiology, Musculoskeletal Division, Cleveland, OH (United States); Chang, I. Yuan Joseph [Texas Scottish Rite Hospital for Children, Dallas, TX (United States)

    2018-01-15

    To compare diagnostic performance of a 5-min knee MRI protocol to that of a standard knee MRI. One hundred 3 T (100 patients, mean 38.8 years) and 50 1.5 T (46 patients, mean 46.4 years) MRIs, consisting of 5 fast, 2D multi-planar fast-spin-echo (FSE) sequences and five standard multiplanar FSE sequences, from two academic centers (1/2015-1/2016), were retrospectively reviewed by four musculoskeletal radiologists. Agreement between fast and standard (interprotocol agreement) and between standard (intraprotocol agreement) readings for meniscal, ligamentous, chondral, and bone pathology was compared for interchangeability. Frequency of major findings, sensitivity, and specificity was also tested for each protocol. Interprotocol agreement using fast MRI was similar to intraprotocol agreement with standard MRI (83.0-99.5%), with no excess disagreement (≤ 1.2; 95% CI, -4.2 to 3.8%), across all structures. Frequency of major findings (1.1-22.4% across structures) on fast and standard MRI was not significantly different (p ≥ 0.215), except more ACL tears on fast MRI (p = 0.021) and more cartilage defects on standard MRI (p < 0.001). Sensitivities (59-100%) and specificities (73-99%) of fast and standard MRI were not significantly different for meniscal and ligament tears (95% CI for difference, -0.08-0.08). For cartilage defects, fast MRI was slightly less sensitive (95% CI for difference, -0.125 to -0.01) but slightly more specific (95% CI for difference, 0.01-0.5) than standard MRI. A fast 5-min MRI protocol is interchangeable with and has similar accuracy to a standard knee MRI for evaluating internal derangement of the knee. (orig.)

  15. Comparison of a fast 5-min knee MRI protocol with a standard knee MRI protocol. A multi-institutional multi-reader study

    International Nuclear Information System (INIS)

    FitzGerald Alaia, Erin; Beltran, Luis S.; Garwood, Elisabeth; Burke, Christopher J.; Gyftopoulos, Soterios; Benedick, Alex; Obuchowski, Nancy A.; Polster, Joshua M.; Schils, Jean; Subhas, Naveen; Chang, I. Yuan Joseph

    2018-01-01

    To compare diagnostic performance of a 5-min knee MRI protocol to that of a standard knee MRI. One hundred 3 T (100 patients, mean 38.8 years) and 50 1.5 T (46 patients, mean 46.4 years) MRIs, consisting of 5 fast, 2D multi-planar fast-spin-echo (FSE) sequences and five standard multiplanar FSE sequences, from two academic centers (1/2015-1/2016), were retrospectively reviewed by four musculoskeletal radiologists. Agreement between fast and standard (interprotocol agreement) and between standard (intraprotocol agreement) readings for meniscal, ligamentous, chondral, and bone pathology was compared for interchangeability. Frequency of major findings, sensitivity, and specificity was also tested for each protocol. Interprotocol agreement using fast MRI was similar to intraprotocol agreement with standard MRI (83.0-99.5%), with no excess disagreement (≤ 1.2; 95% CI, -4.2 to 3.8%), across all structures. Frequency of major findings (1.1-22.4% across structures) on fast and standard MRI was not significantly different (p ≥ 0.215), except more ACL tears on fast MRI (p = 0.021) and more cartilage defects on standard MRI (p < 0.001). Sensitivities (59-100%) and specificities (73-99%) of fast and standard MRI were not significantly different for meniscal and ligament tears (95% CI for difference, -0.08-0.08). For cartilage defects, fast MRI was slightly less sensitive (95% CI for difference, -0.125 to -0.01) but slightly more specific (95% CI for difference, 0.01-0.5) than standard MRI. A fast 5-min MRI protocol is interchangeable with and has similar accuracy to a standard knee MRI for evaluating internal derangement of the knee. (orig.)

  16. Ovarian volume and antral follicle count assessed by MRI and transvaginal ultrasonography: a methodological study.

    Science.gov (United States)

    Leonhardt, Henrik; Gull, Berit; Stener-Victorin, Elisabet; Hellström, Mikael

    2014-03-01

    Ultrasonographic measurements of ovarian volume and antral follicle count are of clinical importance as diagnostic features of polycystic ovarian syndrome (PCOS), and as a parameter in estimation of ovarian follicular reserve in infertility care. To compare two-dimensional (2D)/three-dimensional (3D) transvaginal ultrasonography (TVUS) and magnetic resonance imaging (MRI) for estimation of ovarian volume and antral follicle count, and to assess reproducibility and inter-observer agreement of MRI measurements. Volumes of 172 ovaries in 99 women aged 21-37 years were calculated (length x width x height x 0.523) with conventional 2D TVUS and 2D MRI. Semi-automatic estimates of ovarian volumes were obtained by 3D MRI. Antral follicles were counted manually on 2D MRI and automatically by 3D TVUS (SonoAVC), and stratified according to follicle size. Mean ovarian volume assessed by 2D TVUS (13.1 ± 6.4 mL) was larger than assessed by 2D MRI (9.6 ± 4.1) and 3D MRI (11.4 ± 4.5) (P 0.77. 2D MRI reveals more antral follicles, especially of small size, than 3D TVUS. Ovarian volume estimation by MRI provides smaller volumes than by the reference standard 2D TVUS. Ovarian volume estimation by 3D MRI, allowing independence of non-ellipsoid ovarian shape measurement errors, provides volumes closer to 2D TVUS values than does 2D MRI. Reproducibility and inter-observer agreement of 2D MRI measurements of ovarian volume and total follicle count are good.

  17. 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.)

  18. 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.)

  19. 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.)

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. 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.)

  6. Abdominal MRI at 3.0 T: LAVA-Flex compared with conventional fat suppression T1-weighted images.

    Science.gov (United States)

    Li, Xing Hui; Zhu, Jiang; Zhang, Xiao Ming; Ji, Yi Fan; Chen, Tian Wu; Huang, Xiao Hua; Yang, Lin; Zeng, Nan Lin

    2014-07-01

    To study liver imaging with volume acceleration-flexible (LAVA-Flex) for abdominal magnetic resonance imaging (MRI) at 3.0 T and compare the image quality of abdominal organs between LAVA-Flex and fast spoiled gradient-recalled (FSPGR) T1-weighted imaging. Our Institutional Review Board approval was obtained in this retrospective study. Sixty-nine subjects had both FSPGR and LAVA-Flex sequences. Two radiologists independently scored the acquisitions for image quality, fat suppression quality, and artifacts and the values obtained were compared with the Wilcoxon signed rank test. According to the signal intensity (SI) measurements, the uniformity of fat suppression, the contrast between muscle and fat and normal liver and liver lesions were compared by the paired t-test. The liver and spleen SI on the fat-only phase were analyzed in the fatty liver patients. Compared with FSPGR imaging, LAVA-Flex images had better and more homogenous fat suppression and lower susceptibility artifact (qualitative scores: 4.70 vs. 4.00, 4.86% vs. 7.14%, 4.60 and 4.10, respectively). The contrast between muscle and fat and between the liver and pathologic lesions was significantly improved on the LAVA-Flex sequence. The contrast value of the fatty liver and spleen was higher than that of the liver and spleen. The LAVA-Flex sequence offers superior and more homogenous fat suppression of the abdomen than does the FSPGR sequence. The fat-only phase can be a simple and effective method of assessing fatty liver. © 2013 Wiley Periodicals, Inc.

  7. Effect of heavy training in contact sports on MRI findings in the pubic region of asymptomatic competitive athletes compared with non-athlete controls

    Energy Technology Data Exchange (ETDEWEB)

    Paajanen, Hannu [Kuopio University Hospital, Department of Surgery, Kuopio (Finland); Hermunen, Heikki; Karonen, Jari [Central Hospital of Mikkeli, Department of Radiology, Mikkeli (Finland)

    2011-01-15

    Bone marrow edema (BME) at the pubic symphysis on magnetic resonance imaging (MRI) is usually associated with groin pain and stress injury of the pubic bone. Little is known of the pubic MR imaging findings of asymptomatic heavy training athletes in contact sports. Pelvic MRI of male asymptomatic soccer (n = 10), ice hockey (n = 10), bandy (n = 10) and female floor-ball players (n = 10) were compared with non-athlete controls (10 males, 10 females) without groin pain to analyse the presence of BME (on a four-point scale). To study the possible changes of BME directly following heavy physical activity, 10 bandy players underwent MRI before and immediately after a 2-h training session. Magnetic resonance imaging showed minimal BME (grade 1) at the pubic symphysis in 19 of the 40 athletes (48%). Two soccer and 2 ice hockey players (20%) had moderate grade 2 pubic edema, but severe grade 3 BME findings were not found. Also 10 out of 20 (50%) of controls had grade 1 BME. The extent of increased signal was equally distributed in the asymptomatic athletes of different contact sports and controls. A heavy 2-h training session did not cause any enhanced signal at the pubic symphysis. This study indicates that the presence of grade 1 pubic BME was a frequent finding in contact sports and comparable to that in non-athletes. Grade 2 BME was found only in asymptomatic athletes undergoing heavy training. (orig.)

  8. Effect of heavy training in contact sports on MRI findings in the pubic region of asymptomatic competitive athletes compared with non-athlete controls

    International Nuclear Information System (INIS)

    Paajanen, Hannu; Hermunen, Heikki; Karonen, Jari

    2011-01-01

    Bone marrow edema (BME) at the pubic symphysis on magnetic resonance imaging (MRI) is usually associated with groin pain and stress injury of the pubic bone. Little is known of the pubic MR imaging findings of asymptomatic heavy training athletes in contact sports. Pelvic MRI of male asymptomatic soccer (n = 10), ice hockey (n = 10), bandy (n = 10) and female floor-ball players (n = 10) were compared with non-athlete controls (10 males, 10 females) without groin pain to analyse the presence of BME (on a four-point scale). To study the possible changes of BME directly following heavy physical activity, 10 bandy players underwent MRI before and immediately after a 2-h training session. Magnetic resonance imaging showed minimal BME (grade 1) at the pubic symphysis in 19 of the 40 athletes (48%). Two soccer and 2 ice hockey players (20%) had moderate grade 2 pubic edema, but severe grade 3 BME findings were not found. Also 10 out of 20 (50%) of controls had grade 1 BME. The extent of increased signal was equally distributed in the asymptomatic athletes of different contact sports and controls. A heavy 2-h training session did not cause any enhanced signal at the pubic symphysis. This study indicates that the presence of grade 1 pubic BME was a frequent finding in contact sports and comparable to that in non-athletes. Grade 2 BME was found only in asymptomatic athletes undergoing heavy training. (orig.)

  9. 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.

  10. Surface-Based fMRI-Driven Diffusion Tractography in the Presence of Significant Brain Pathology: A Study Linking Structure and Function in Cerebral Palsy

    Science.gov (United States)

    Cunnington, Ross; Boyd, Roslyn N.; Rose, Stephen E.

    2016-01-01

    Diffusion MRI (dMRI) tractography analyses are difficult to perform in the presence of brain pathology. Automated methods that rely on cortical parcellation for structural connectivity studies often fail, while manually defining regions is extremely time consuming and can introduce human error. Both methods also make assumptions about structure-function relationships that may not hold after cortical reorganisation. Seeding tractography with functional-MRI (fMRI) activation is an emerging method that reduces these confounds, but inherent smoothing of fMRI signal may result in the inclusion of irrelevant pathways. This paper describes a novel fMRI-seeded dMRI-analysis pipeline based on surface-meshes that reduces these issues and utilises machine-learning to generate task specific white matter pathways, minimising the requirement for manually-drawn ROIs. We directly compared this new strategy to a standard voxelwise fMRI-dMRI approach, by investigating correlations between clinical scores and dMRI metrics of thalamocortical and corticomotor tracts in 31 children with unilateral cerebral palsy. The surface-based approach successfully processed more participants (87%) than the voxel-based approach (65%), and provided significantly more-coherent tractography. Significant correlations between dMRI metrics and five clinical scores of function were found for the more superior regions of these tracts. These significant correlations were stronger and more frequently found with the surface-based method (15/20 investigated were significant; R2 = 0.43–0.73) than the voxelwise analysis (2 sig. correlations; 0.38 & 0.49). More restricted fMRI signal, better-constrained tractography, and the novel track-classification method all appeared to contribute toward these differences. PMID:27487011

  11. 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

  12. An Observational Study to Assess Brain MRI Change and Disease Progression in Multiple Sclerosis Clinical Practice-The MS-MRIUS Study.

    Science.gov (United States)

    Zivadinov, Robert; Khan, Nasreen; Medin, Jennie; Christoffersen, Pia; Price, Jennifer; Korn, Jonathan R; Bonzani, Ian; Dwyer, Michael G; Bergsland, Niels; Carl, Ellen; Silva, Diego; Weinstock-Guttman, Bianca

    2017-05-01

    To describe methodology, interim baseline, and longitudinal magnetic resonance imaging (MRI) acquisition parameter characteristics of the multiple sclerosis clinical outcome and MRI in the United States (MS-MRIUS). The MS-MRIUS is an ongoing longitudinal and retrospective study of MS patients on fingolimod. Clinical and brain MRI image scan data were collected from 600 patients across 33 MS centers in the United States. MRI brain outcomes included change in whole-brain volume, lateral ventricle volume, T2- and T1-lesion volumes, and new/enlarging T2 and gadolinium-enhancing lesions. Interim baseline and longitudinal MRI acquisition parameters results are presented for 252 patients. Mean age was 44 years and 81% were female. Forty percent of scans had 3-dimensional (3D) T1 sequence in the preindex period, increasing to 50% in the postindex period. Use of 2-dimensional (2D) T1 sequence decreased over time from 85% in the preindex period to 65% in the postindex. About 95% of the scans with FLAIR and 2D T1-WI were considered acceptable or good quality compared to 99-100% with 3D T1-WI. There were notable changes in MRI hardware, software, and coil (39.5% in preindex to index and 50% in index to postindex). MRI sequence parameters (orientation, thickness, or protocol) differed for 36%, 29%, and 20% of index/postindex scans for FLAIR, 2D T1-WI, and 3D T1-WI, respectively. The MS-MRIUS study linked the clinical and brain MRI outcomes into an integrated database to create a cohort of fingolimod patients in real-world practice. Variability was observed in MRI acquisition protocols overtime. © 2016 The Authors. Journal of Neuroimaging published by Wiley Periodicals, Inc. on behalf of American Society of Neuroimaging.

  13. A comparative study of postmortem MR imaging and pathological examination of human brain specimens

    International Nuclear Information System (INIS)

    Shiga, Tohru

    1998-01-01

    This study was designed to assess the value of MRI of the postmortem brain specimens by comparing MRI findings with neuropathological findings. Postmortem MRI was performed in 17 consecutive formalin-fixed whole brains comprising 3 with primary CNS neoplasm, 1 with metastatic brain tumor, 6 with cerebral vascular disease (CVD), 1 with degenerative disease, 1 with spongy state in thalamus, and 5 with no abnormality. Postmortem T2WI detected all neuropathological abnormalities but sparsely distributed tumor cells without edema. In one case of CNS neoplasm, the tumor lesions with little necrosis or edema showed isointensity to brain tissue, while others with large amounts of necrosis and edema showed high signal intensity on T2WI. In the cases of CVD, the major signal changes on T2WI were due to edema, necrosis, and damage of the organization as observed on neuropathological studies. There was one case in which both MRI and neuropathological examination showed an abnormality, which was pathologically unexplainable. In two cases, findings of postmortem MRI were more apparent than those of macroscopic examination. Postmortem MRI appeared different from premortem MRI in one of the rest three cases whereas the postmortem MRI correlated well with neuropathological findings. Progression of the disease immediately before death may have caused this difference. In conclusion, the correlations between MRI and neuropathological findings facilitate understanding the mechanisms responsible for MRI abnormalities. An increase in free water in edema, necrosis, and damage in brain tissue can explain an increased signal intensity on T2WI. Postmortem MRI may contribute to the effective pathological examination by pointing out subtle abnormalities before brain cutting. (author)

  14. 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.

  15. Distinct neuromuscular phenotypes in myotonic dystrophy types 1 and 2 : a whole body highfield MRI study.

    Science.gov (United States)

    Kornblum, Cornelia; Lutterbey, Götz; Bogdanow, Manuela; Kesper, Kristina; Schild, Hans; Schröder, Rolf; Wattjes, Mike Peter

    2006-06-01

    Myotonic Dystrophy Type 1 (DM1) and 2 (DM2) present with distinct though overlapping clinical phenotypes. Comparative imaging data on skeletal muscle involvement are not at present available. We used the novel technique of whole body 3.0 Tesla (T) Magnetic Resonance Imaging (MRI) to further characterize musculoskeletal features in DM2 and compared the results with DM1.MRI findings of 15 DM1 and 14 DM2 patients were evaluated with respect to patterns of skeletal muscle affection and clinical data using the Muscular Impairment Rating Scale (MIRS) and Medical Research Council scale (MRC). All DM1 patients had pathological MRI compared with only 5 DM2 patients. In contrast to DM2, DM1 patients showed a characteristic distribution of muscle involvement with frequent and early degeneration of the medial heads of gastrocnemius muscles, and a perifemoral semilunar pattern of quadriceps muscle affection sparing the rectus femoris. The most frequently affected muscles in DM1 were the medial heads of gastrocnemius, soleus, and vastus medialis muscles. In DM2, however, the erector spinae and gluteus maximus muscles were most vulnerable to degeneration. MRI data were in line with the clinical grading in 12 DM1 and 3 DM2 patients. In 3 DM1 and 5 DM2 patients, MRI detected subclinical muscle involvement. 9 DM2 patients with mild to moderate proximal muscle weakness and/or myalgias had normal MRI. Pathological MRI changes in DM2 emerged with increasing age and were restricted to women. Whole body 3.0T MRI is a sensitive imaging technique that demonstrated a characteristic skeletal muscle affection in DM1. In contrast, MRI was no reliable indicator for skeletal muscle involvement in mildly affected DM2 patients since myalgia and mild paresis were usually not reflected by MRI signal alterations.

  16. Bone scintigraphy compared to MRI and ultrasound in the early diagnosis of arthritis

    International Nuclear Information System (INIS)

    Sandrock, D.

    2006-01-01

    Chronic inflammatory arthritis is recognized specifically by bone erosions, caused by characteristic pannus tissue. In the finger joints dynamic low-Tesla MRI is nearly double but not completely sensitive in the detection of erosions than conventional radiography, sonography takes an intermediate position. Less specific signs of synovitis and tenosynovitis are shown with high sensitivity by both 3(2)-phase bone scintigraphy and ultrasound, MRI is less sensitive in this respect. However, standard situation of inflammation in bone scintigraphy - positive finding in early as well as late phase - is of surprisingly low sensitivity, any singular finding in the early or late phase has to be regarded as positive. Specificity of these singular findings is nevertheless sufficiently high, acute inflammatory joint changes and even erosions are also seen with MRI in obviously healthy persons. Only 2-phase bone scintigraphy is easily able to present a simultaneous survey of all joints of the body. For this reason 2-phase bone scintigraphy is most suitable for exclusion but also for primary diagnosis of disease, specification must be done afterwards by other imaging modalities or by laboratory findings. (orig.)

  17. Cine MRI of swallowing in patients with advanced oral or oropharyngeal carcinoma: a feasibility study

    NARCIS (Netherlands)

    Kreeft, Anne Marijn; Rasch, Coen R. N.; Muller, Sara H.; Pameijer, Frank A.; Hallo, Eeke; Balm, Alfons J. M.

    2012-01-01

    Treatment of oral and oropharyngeal cancer may cause dysphagia. Purpose is to examine whether cine magnetic resonance imaging (MRI) yields additional information compared to standard examination in the evaluation of posttreatment dysphagia and mobility of oral and oropharyngeal structures.

  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. [Comparative studies of face recognition].

    Science.gov (United States)

    Kawai, Nobuyuki

    2012-07-01

    Every human being is proficient in face recognition. However, the reason for and the manner in which humans have attained such an ability remain unknown. These questions can be best answered-through comparative studies of face recognition in non-human animals. Studies in both primates and non-primates show that not only primates, but also non-primates possess the ability to extract information from their conspecifics and from human experimenters. Neural specialization for face recognition is shared with mammals in distant taxa, suggesting that face recognition evolved earlier than the emergence of mammals. A recent study indicated that a social insect, the golden paper wasp, can distinguish their conspecific faces, whereas a closely related species, which has a less complex social lifestyle with just one queen ruling a nest of underlings, did not show strong face recognition for their conspecifics. Social complexity and the need to differentiate between one another likely led humans to evolve their face recognition abilities.

  20. 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.

  1. 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

  2. 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...

  3. [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.

  4. Software-assisted small bowel motility analysis using free-breathing MRI: feasibility study.

    Science.gov (United States)

    Bickelhaupt, Sebastian; Froehlich, Johannes M; Cattin, Roger; Raible, Stephan; Bouquet, Hanspeter; Bill, Urs; Patak, Michael A

    2014-01-01

    To validate a software prototype allowing for small bowel motility analysis in free breathing by comparing it to manual measurements. In all, 25 patients (15 male, 10 female; mean age 39 years) were included in this Institutional Review Board-approved, retrospective study. Magnetic resonance imaging (MRI) was performed on a 1.5T system after standardized preparation acquiring motility sequences in free breathing over 69-84 seconds. Small bowel motility was analyzed manually and with the software. Functional parameters, measurement time, and reproducibility were compared using the coefficient of variance and paired Student's t-test. Correlation was analyzed using Pearson's correlation coefficient and linear regression. The 25 segments were analyzed twice both by hand and using the software with automatic breathing correction. All assessed parameters significantly correlated between the methods (P software (3.90%, standard deviation [SD] ± 5.69) than manual examinations (9.77%, SD ± 11.08). The time needed was significantly less (P software (4.52 minutes, SD ± 1.58) compared to manual measurement, lasting 17.48 minutes for manual (SD ± 1.75 minutes). The use of the software proves reliable and faster small bowel motility measurements in free-breathing MRI compared to manual analyses. The new technique allows for analyses of prolonged sequences acquired in free breathing, improving the informative value of the examinations by amplifying the evaluable data. Copyright © 2013 Wiley Periodicals, Inc.

  5. 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.

  6. Language Lateralization in Children Aged 10 to 11 Years: A Combined fMRI and Dichotic Listening Study

    Science.gov (United States)

    Norrelgen, Fritjof; Lilja, Anders; Ingvar, Martin; Gisselgård, Jens; Fransson, Peter

    2012-01-01

    Objective The aims of this study were to develop and assess a method to map language networks in children with two auditory fMRI protocols in combination with a dichotic listening task (DL). The method is intended for pediatric patients prior to epilepsy surgery. To evaluate the potential clinical usefulness of the method we first wanted to assess data from a group of healthy children. Methods In a first step language test materials were developed, intended for subsequent implementation in fMRI protocols. An evaluation of this material was done in 30 children with typical development, 10 from the 1st, 4th and the 7th grade, respectively. The language test material was then adapted and implemented in two fMRI protocols intended to target frontal and posterior language networks. In a second step language lateralization was assessed in 17 typical 10–11 year olds with fMRI and DL. To reach a conclusion about language lateralization, firstly, quantitative analyses of the index data from the two fMRI tasks and the index data from the DL task were done separately. In a second step a set of criteria were applied to these results to reach a conclusion about language lateralization. The steps of these analyses are described in detail. Results The behavioral assessment of the language test material showed that it was well suited for typical children. The results of the language lateralization assessments, based on fMRI data and DL data, showed that for 15 of the 17 subjects (88%) a conclusion could be reached about hemispheric language dominance. In 2 cases (12%) DL provided critical data. Conclusions The employment of DL combined with language mapping using fMRI for assessing hemispheric language dominance is novel and it was deemed valuable since it provided additional information compared to the results gained from each method individually. PMID:23284796

  7. Language lateralization in children aged 10 to 11 years: a combined fMRI and dichotic listening study.

    Directory of Open Access Journals (Sweden)

    Fritjof Norrelgen

    Full Text Available OBJECTIVE: The aims of this study were to develop and assess a method to map language networks in children with two auditory fMRI protocols in combination with a dichotic listening task (DL. The method is intended for pediatric patients prior to epilepsy surgery. To evaluate the potential clinical usefulness of the method we first wanted to assess data from a group of healthy children. METHODS: In a first step language test materials were developed, intended for subsequent implementation in fMRI protocols. An evaluation of this material was done in 30 children with typical development, 10 from the 1(st, 4(th and the 7(th grade, respectively. The language test material was then adapted and implemented in two fMRI protocols intended to target frontal and posterior language networks. In a second step language lateralization was assessed in 17 typical 10-11 year olds with fMRI and DL. To reach a conclusion about language lateralization, firstly, quantitative analyses of the index data from the two fMRI tasks and the index data from the DL task were done separately. In a second step a set of criteria were applied to these results to reach a conclusion about language lateralization. The steps of these analyses are described in detail. RESULTS: The behavioral assessment of the language test material showed that it was well suited for typical children. The results of the language lateralization assessments, based on fMRI data and DL data, showed that for 15 of the 17 subjects (88% a conclusion could be reached about hemispheric language dominance. In 2 cases (12% DL provided critical data. CONCLUSIONS: The employment of DL combined with language mapping using fMRI for assessing hemispheric language dominance is novel and it was deemed valuable since it provided additional information compared to the results gained from each method individually.

  8. 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

  9. 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)

  10. Virtual visual reminiscing pain stimulation of allodynia patients activates cortical representation of pain and emotions. fMRI study

    International Nuclear Information System (INIS)

    Ikemoto, Tatsunori; Ushida, Takahiro; Taniguchi, Shinichirou; Tania, Toshikazu; Zinchuk, V.; Morio, Kazuo; Sasaki, Toshikazu

    2004-01-01

    It is widely known that sensation of the pain is derived from sensory-discriminative factor and emotional factor. Especially in chronic pain, emotional factors and psychosocial backgrounds are more likely to contribute for the patients' discomfort. The aim of this study is to investigate how emotional factor of pain participates in intractable pain. We employed functional MRI (fMRI) to compare the brain activations occurring in the orthopaedic neuropathic pain patients with allodynia and normal individuals in response to the visual virtual painful experience. During fMRI scanning, a video demonstrating an actual tactile stimulation of the palm and its imitation were shown to participants. In contrast to normal individuals, allodynia patients also displayed activation of the areas reflecting emotions: frontal lobe and anterior cingulate. These findings suggest that brain have important role in the development and maintaining of peripheral originated chronic painful condition. (author)

  11. Effect of bread gluten content on gastrointestinal function: a crossover MRI study on healthy humans.

    Science.gov (United States)

    Coletta, Marina; Gates, Fred K; Marciani, Luca; Shiwani, Henna; Major, Giles; Hoad, Caroline L; Chaddock, Gemma; Gowland, Penny A; Spiller, Robin C

    2016-01-14

    Gluten is a crucial functional component of bread, but the effect of increasing gluten content on gastrointestinal (GI) function remains uncertain. Our aim was to investigate the effect of increasing gluten content on GI function and symptoms in healthy participants using the unique capabilities of MRI. A total of twelve healthy participants completed this randomised, mechanistic, open-label, three-way crossover study. On days 1 and 2 they consumed either gluten-free bread (GFB), or normal gluten content bread (NGCB) or added gluten content bread (AGCB). The same bread was consumed on day 3, and MRI scans were performed every 60 min from fasting baseline up to 360 min after eating. The appearance of the gastric chime in the images was assessed using a visual heterogeneity score. Gastric volumes, the small bowel water content (SBWC), colonic volumes and colonic gas content and GI symptoms were measured. Fasting transverse colonic volume after the 2-d preload was significantly higher after GFB compared with NGCB and AGCB with a dose-dependent response (289 (SEM 96) v. 212 (SEM 74) v. 179 (SEM 87) ml, respectively; P=0·02). The intragastric chyme heterogeneity score was higher for the bread with increased gluten (AGCB 6 (interquartile range (IQR) 0·5) compared with GFB 3 (IQR 0·5); P=0·003). However, gastric half-emptying time was not different between breads nor were study day GI symptoms, postprandial SBWC, colonic volume and gas content. This MRI study showed novel mechanistic insights in the GI responses to different breads, which are poorly understood notwithstanding the importance of this staple food.

  12. Distinguishing the processing of gestures from signs in deaf individuals: an fMRI study.

    Science.gov (United States)

    Husain, Fatima T; Patkin, Debra J; Thai-Van, Hung; Braun, Allen R; Horwitz, Barry

    2009-06-18

    Manual gestures occur on a continuum from co-speech gesticulations to conventionalized emblems to language signs. Our goal in the present study was to understand the neural bases of the processing of gestures along such a continuum. We studied four types of gestures, varying along linguistic and semantic dimensions: linguistic and meaningful American Sign Language (ASL), non-meaningful pseudo-ASL, meaningful emblematic, and nonlinguistic, non-meaningful made-up gestures. Pre-lingually deaf, native signers of ASL participated in the fMRI study and performed two tasks while viewing videos of the gestures: a visuo-spatial (identity) discrimination task and a category discrimination task. We found that the categorization task activated left ventral middle and inferior frontal gyrus, among other regions, to a greater extent compared to the visual discrimination task, supporting the idea of semantic-level processing of the gestures. The reverse contrast resulted in enhanced activity of bilateral intraparietal sulcus, supporting the idea of featural-level processing (analogous to phonological-level processing of speech sounds) of the gestures. Regardless of the task, we found that brain activation patterns for the nonlinguistic, non-meaningful gestures were the most different compared to the ASL gestures. The activation patterns for the emblems were most similar to those of the ASL gestures and those of the pseudo-ASL were most similar to the nonlinguistic, non-meaningful gestures. The fMRI results provide partial support for the conceptualization of different gestures as belonging to a continuum and the variance in the fMRI results was best explained by differences in the processing of gestures along the semantic dimension.

  13. 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.

  14. 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)

  15. 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.

  16. 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)

  17. 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).

  18. Comparative neuroimaging in children with cerebral palsy using fMRI and a novel EEG-based brain mapping during a motor task--a preliminary investigation.

    Science.gov (United States)

    Lee, Jae Jin; Lee, Dong Ryul; Shin, Yoon Kyum; Lee, Nam Gi; Han, Bong S; You, Sung Joshua Hyun

    2013-01-01

    The purpose of this study was to compare topographical maps using a novel EEG-based brain mapping system with fMRI in normal and children with cerebral palsy (CP) during a grasping motor task. A normal child (mean ± SD = 13 ± 0 yrs) and four children with CP (mean ± SD = 10.25 ± 2.86 yrs) were recruited from a local community school and medical center. A novel EEG-based brain mapping system with 30 scalp sites (an extension of the 10-20 system) and a 3T MR scanner were used to observe cortical activation patterns during a grasping motor task. Descriptive analysis. In the EEG brain mapping data, the sensorimotor cortex (SMC) and inferior parietal cortex (IPC) were activated in all of the children. The children with CP showed additional activation areas in the premotor cortex (PMC), superior parietal cortex (SPC), and prefrontal cortex (PFC). In the fMRI brain mapping data, SMC activation was observed in all of the children, and the children with CP showed additional activation areas in the PMC and primary somatosensory cortex (PSC). The EEG-based topographical maps were equivalent to the maps obtained from fMRI during the grasping motor task. The results indicate that our novel EEG-based brain mapping system is useful for probing cortical activation patterns in normal children and children with CP.

  19. 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.)

  20. 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)

  1. Comparative study of ultrasound imaging, computed tomography and magnetic resonance imaging in gynecology

    International Nuclear Information System (INIS)

    Ishii, Kenji; Kobayashi, Hisaaki; Hoshihara, Takayuki; Kobayashi, Mitsunao; Suda, Yoshio; Takenaka, Eiichi; Sasa, Hidenori.

    1989-01-01

    We studied 18 patients who were operated at the National Defense Medical College Hospital and confirmed by pathological diagnosis. We compared ultrasound imaging, computed tomography (CT) and magnetic resonance imaging (MRI) of the patients. MRI was useful to diagnose enlargement of the uterine cavity and a small amount of ascites and to understand orientation of the pelvic organs. Ultrasound imaging is the most useful examination to diagnose gynecological diseases. But when it is difficult to diagnose by ultrasound imaging alone, we should employ either CT or MRI, or preferably both. (author)

  2. Comparative analysis of methods for extracting vessel network on breast MRI images

    Science.gov (United States)

    Gaizer, Bence T.; Vassiou, Katerina G.; Lavdas, Eleftherios; Arvanitis, Dimitrios L.; Fezoulidis, Ioannis V.; Glotsos, Dimitris T.

    2017-11-01

    Digital processing of MRI images aims to provide an automatized diagnostic evaluation of regular health screenings. Cancerous lesions are proven to cause an alteration in the vessel structure of the diseased organ. Currently there are several methods used for extraction of the vessel network in order to quantify its properties. In this work MRI images (Signa HDx 3.0T, GE Healthcare, courtesy of University Hospital of Larissa) of 30 female breasts were subjected to three different vessel extraction algorithms to determine the location of their vascular network. The first method is an experiment to build a graph over known points of the vessel network; the second algorithm aims to determine the direction and diameter of vessels at these points; the third approach is a seed growing algorithm, spreading selection to neighbors of the known vessel pixels. The possibilities shown by the different methods were analyzed, and quantitative measurements were performed. The data provided by these measurements showed no clear correlation with the presence or malignancy of tumors, based on the radiological diagnosis of skilled physicians.

  3. Iron in typical and atypical parkinsonism – Mössbauer spectroscopy and MRI studies

    Energy Technology Data Exchange (ETDEWEB)

    Kuliński, R. [Bródno Hospital, MRI Lab (Poland); Bauminger, E. R. [Hebrew University, Racah Institute of Physics (Israel); Friedman, A. [Medical University of Warsaw, Department of Neurology (Poland); Duda, P.; Gałązka-Friedman, J., E-mail: jgfrie@if.pw.edu.pl [Warsaw University of Technology, Faculty of Physics (Poland)

    2016-12-15

    Iron may play important role in neurodegeneration. The results of comparative studies of human brain areas (control and pathological) performed by Mössbauer spectroscopy (MS) and magnetic resonance imaging (MRI) techniques are presented. Mössbauer spectroscopy demonstrated a higher concentration of iron in atypical parkinsonism (progressive supranuclear palsy PSP) in the brain areas Substantia Nigra (SN) and Globus Pallidus (GP) involved in this pathological process, compared to control, while the concentration of iron in pathological tissues in typical parkinsonism (Parkinson’s disease - PD) did not differ from that in control. These results were compared with the changes in 1/T1 and 1/T2 (T1 and T2 being the relaxation times determined by MRI). A good linear correlation curve was found between the concentration of iron as determined by MS in different areas of control human brains and between 1/T1 and 1/T2. Whereas the finding in PSP-GP (the brain area involved in PSP) also fitted to such a correlation, this was not so for the correlation between pathological SN – the brain area involved in both diseases – and 1/T2, indicating a dependence of T2 on other factors than just the concentration of iron.

  4. Translating state-of-the-art spinal cord MRI techniques to clinical use: A systematic review of clinical studies utilizing DTI, MT, MWF, MRS, and fMRI.

    Science.gov (United States)

    Martin, Allan R; Aleksanderek, Izabela; Cohen-Adad, Julien; Tarmohamed, Zenovia; Tetreault, Lindsay; Smith, Nathaniel; Cadotte, David W; Crawley, Adrian; Ginsberg, Howard; Mikulis, David J; Fehlings, Michael G

    2016-01-01

    studies, rendering direct comparisons of metrics invalid. The DTI metric fractional anisotropy (FA) had the strongest evidence of utility, with moderate quality evidence for its use as a biomarker showing correlation with disability in several clinical pathologies, and a low level of evidence that it identifies tissue injury (in terms of group differences) compared with healthy controls. However, insufficient evidence exists to determine its utility as a sensitive and specific diagnostic test or as a tool to predict clinical outcomes. Very low quality evidence suggests that other metrics also show group differences compared with controls, including DTI metrics mean diffusivity (MD) and radial diffusivity (RD), the diffusional kurtosis imaging (DKI) metric mean kurtosis (MK), MT metrics MT ratio (MTR) and MT cerebrospinal fluid ratio (MTCSF), and the MRS metric of N-acetylaspartate (NAA) concentration, although these results were somewhat inconsistent. State-of-the-art spinal cord MRI techniques are emerging with great potential to improve the diagnosis and management of various spinal pathologies, but the current body of evidence has only showed limited clinical utility to date. Among these imaging tools DTI is the most mature, but further work is necessary to standardize and validate its use before it will be adopted in the clinical realm. Large, well-designed studies with a priori hypotheses, standardized acquisition methods, detailed clinical data collection, and robust automated analysis techniques are needed to fully demonstrate the potential of these rapidly evolving techniques.

  5. Sex work: a comparative study.

    Science.gov (United States)

    McCarthy, Bill; Benoit, Cecilia; Jansson, Mikael

    2014-10-01

    Explanations of adult involvement in sex work typically adopt one of two approaches. One perspective highlights a variety of negative experiences in childhood and adolescence, including physical and sexual abuse, family instability, poverty, associations with "pimps" and other exploiters, homelessness, and drug use. An alternative account recognizes that some of these factors may be involved, but underscores the contribution of more immediate circumstances, such as current economic needs, human capital, and employment opportunities. Prior research offers a limited assessment of these contrasting claims: most studies have focused exclusively on people working in the sex industry and they have not assessed the independent effects of life course variables central to these two perspectives. We add to this literature with an analysis that drew on insights from life course and life-span development theories and considered the contributions of factors from childhood, adolescence, and adulthood. Our comparative approach examined predictors of employment in sex work relative to two other low-income service or care work occupations: food and beverage serving and barbering and hairstyling. Using data from a study of almost 600 workers from two cities, one in Canada and the other in the United States, we found that both immediate circumstances and negative experiences from early life are related to current sex work involvement: childhood poverty, abuse, and family instability were independently associated with adult sex work, as were limited education and employment experience, adult drug use, and marital status.

  6. 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.

  7. Investigating Inhibitory Control in Children with Epilepsy: An fMRI Study

    Science.gov (United States)

    Triplett, Regina L.; Velanova, Katerina; Luna, Beatriz; Padmanabhan, Aarthi; Gaillard, William D.; Asato, Miya R.

    2014-01-01

    SUMMARY Objective Deficits in executive function are increasingly noted in children with epilepsy and have been associated with poor academic and psychosocial outcomes. Impaired inhibitory control contributes to executive dysfunction in children with epilepsy; however, its neuroanatomic basis has not yet been investigated. We used functional Magnetic Resonance Imaging (fMRI) to probe the integrity of activation in brain regions underlying inhibitory control in children with epilepsy. Methods This cross-sectional study consisted of 34 children aged 8 to 17 years: 17 with well-controlled epilepsy and 17 age-and sex-matched controls. Participants performed the antisaccade (AS) task, representative of inhibitory control, during fMRI scanning. We compared AS performance during neutral and reward task conditions and evaluated task-related blood-oxygen level dependent (BOLD) activation. Results Children with epilepsy demonstrated impaired AS performance compared to controls during both neutral (non-reward) and reward trials, but exhibited significant task improvement during reward trials. Post-hoc analysis revealed that younger patients made more errors than older patients and all controls. fMRI results showed preserved activation in task-relevant regions in patients and controls, with the exception of increased activation in the left posterior cingulate gyrus in patients specifically with generalized epilepsy across neutral and reward trials. Significance Despite impaired inhibitory control, children with epilepsy accessed typical neural pathways as did their peers without epilepsy. Children with epilepsy showed improved behavioral performance in response to the reward condition, suggesting potential benefits of the use of incentives in cognitive remediation. PMID:25223606

  8. 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)

  9. 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)

  10. 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.

  11. 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.)

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

    Science.gov (United States)

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

    2015-06-01

    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 highresolution T1-weighted MRI; fMRI images were obtained during empathy task in the same session. The analysis was carried out using SPM8 software. On behavioural assessment, schizophrenic patients (83.00+-29.04) showed less scores for sadness compared to healthy controls (128.70+-22.26) (p less than 0.001). fMRI results also showed reduced clusters of activation in the bilateral fusiform gyrus, left lingual gyrus, left middle and inferior occipital gyrus in schizophrenic subjects as compared to controls during empathy task. In the same brain areas, VBM results also showed reduced grey and white matter volumes. The present study provides an evidence for an association between structural alterations and disturbed functional brain activation during empathy task in persons affected with schizophrenia. These findings suggest a biological basis for social cognition deficits in schizophrenics.

  13. 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.

  14. Breast density quantification using magnetic resonance imaging (MRI) with bias field correction: a postmortem study.

    Science.gov (United States)

    Ding, Huanjun; Johnson, Travis; Lin, Muqing; Le, Huy Q; Ducote, Justin L; Su, Min-Ying; Molloi, Sabee

    2013-12-01

    Quantification of breast density based on three-dimensional breast MRI may provide useful information for the early detection of breast cancer. However, the field inhomogeneity can severely challenge the computerized image segmentation process. In this work, the effect of the bias field in breast density quantification has been investigated with a postmortem study. T1-weighted images of 20 pairs of postmortem breasts were acquired on a 1.5 T breast MRI scanner. Two computer-assisted algorithms were used to quantify the volumetric breast density. First, standard fuzzy c-means (FCM) clustering was used on raw images with the bias field present. Then, the coherent local intensity clustering (CLIC) method estimated and corrected the bias field during the iterative tissue segmentation process. Finally, FCM clustering was performed on the bias-field-corrected images produced by CLIC method. The left-right correlation for breasts in the same pair was studied for both segmentation algorithms to evaluate the precision of the tissue classification. Finally, the breast densities measured with the three methods were compared to the gold standard tissue compositions obtained from chemical analysis. The linear correlation coefficient, Pearson's r, was used to evaluate the two image segmentation algorithms and the effect of bias field. The CLIC method successfully corrected the intensity inhomogeneity induced by the bias field. In left-right comparisons, the CLIC method significantly improved the slope and the correlation coefficient of the linear fitting for the glandular volume estimation. The left-right breast density correlation was also increased from 0.93 to 0.98. When compared with the percent fibroglandular volume (%FGV) from chemical analysis, results after bias field correction from both the CLIC the FCM algorithms showed improved linear correlation. As a result, the Pearson's r increased from 0.86 to 0.92 with the bias field correction. The investigated CLIC method

  15. Breast density quantification using magnetic resonance imaging (MRI) with bias field correction: A postmortem study

    International Nuclear Information System (INIS)

    Ding, Huanjun; Johnson, Travis; Lin, Muqing; Le, Huy Q.; Ducote, Justin L.; Su, Min-Ying; Molloi, Sabee

    2013-01-01

    Purpose: Quantification of breast density based on three-dimensional breast MRI may provide useful information for the early detection of breast cancer. However, the field inhomogeneity can severely challenge the computerized image segmentation process. In this work, the effect of the bias field in breast density quantification has been investigated with a postmortem study. Methods: T1-weighted images of 20 pairs of postmortem breasts were acquired on a 1.5 T breast MRI scanner. Two computer-assisted algorithms were used to quantify the volumetric breast density. First, standard fuzzy c-means (FCM) clustering was used on raw images with the bias field present. Then, the coherent local intensity clustering (CLIC) method estimated and corrected the bias field during the iterative tissue segmentation process. Finally, FCM clustering was performed on the bias-field-corrected images produced by CLIC method. The left–right correlation for breasts in the same pair was studied for both segmentation algorithms to evaluate the precision of the tissue classification. Finally, the breast densities measured with the three methods were compared to the gold standard tissue compositions obtained from chemical analysis. The linear correlation coefficient, Pearson'sr, was used to evaluate the two image segmentation algorithms and the effect of bias field. Results: The CLIC method successfully corrected the intensity inhomogeneity induced by the bias field. In left–right comparisons, the CLIC method significantly improved the slope and the correlation coefficient of the linear fitting for the glandular volume estimation. The left–right breast density correlation was also increased from 0.93 to 0.98. When compared with the percent fibroglandular volume (%FGV) from chemical analysis, results after bias field correction from both the CLIC the FCM algorithms showed improved linear correlation. As a result, the Pearson'sr increased from 0.86 to 0.92 with the bias field correction

  16. Whole-body MRI at 1.5 T and 3 T compared with FDG-PET-CT for the detection of tumour recurrence in patients with colorectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, G.P.; Baur-Melnyk, A.; Becker, C.R.; Reiser, M.F.; Hermann, K.A. [Ludwig Maximilian University Munich, Department of Clinical Radiology, University Hospitals Grosshadern, Munich (Germany); Haug, A.; Tiling, R. [University Hospitals Grosshadern, Ludwig Maximilian University Munich, Department of Nuclear Medicine, Munich (Germany); Utzschneider, S. [University Hospitals Grosshadern, Ludwig Maximilian University Munich, Department of Orthopedics, Munich (Germany)

    2009-06-15

    The purpose of this study was to assess the diagnostic accuracy of whole-body MRI (WB-MRI) at 1.5 T or 3 T compared with FDG-PET-CT in the follow-up of patients suffering from colorectal cancer. In a retrospective study, 24 patients with a history of colorectal cancer and suspected tumour recurrence underwent FDG-PET-CT and WB-MRI with the use of parallel imaging (PAT) for follow-up. High resolution coronal T1w-TSE and STIR sequences at four body levels, HASTE imaging of the lungs, contrast-enhanced T1w- and T2w-TSE sequences of the liver, brain, abdomen and pelvis were performed, using WB-MRI at either 1.5 T (n = 14) or 3 T (n = 10). Presence of local recurrent tumour, lymph node involvement and distant metastatic disease was confirmed using radiological follow-up within at least 5 months as a standard of reference. Seventy seven malignant foci in 17 of 24 patients (71%) were detected with both WB-MRI and PET-CT. Both investigations concordantly revealed two local recurrent tumours. PET-CT detected significantly more lymph node metastases (sensitivity 93%, n = 27/29) than WB-MRI (sensitivity 63%, n = 18/29). PET-CT and WB-MRI achieved a similar sensitivity for the detection of organ metastases with 80% and 78%, respectively (37/46 and 36/46). WB-MRI detected brain metastases in one patient. One false-positive local tumour recurrence was indicated by PET-CT. Overall diagnostic accuracy for PET-CT was 91% (sensitivity 86%, specificity 96%) and 83% for WB-MRI (sensitivity 72%, specificity 93%), respectively. Examination time for WB-MRI at 1.5 T and 3 T was 52 min and 43 min, respectively; examination time for PET-CT was 103 min. Initial results suggest that differences in accuracy for local and distant metastases detection using FDG-PET-CT and WB-MRI for integrated screening of tumour recurrence in colorectal cancer depend on the location of the malignant focus. Our results show that nodal disease is better detected using PET-CT, whereas organ disease is depicted

  17. Electrophysiological and MRI study on poor outcome after surgery for cervical myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Kameyama, Osamu; Kawakita, Hirofumi; Ogawa, Ryokei [Kansai Medical Univ., Moriguchi, Osaka (Japan)

    1995-11-01

    Occasionally, the outcome from laminoplasty for cervical spondylosis is disappointing despite an adequate operation. Before surgery, it is difficult to diagnose the pathological extent of the involvement of the spinal cord. The purpose of this study is to determine the efficacy of magnetic resonance imaging (MRI) and of the motor evoked potentials (MEPs) for the indication of the surgery and prognosis. Retrospectively, we investigated the MEPs and the MRI of 31 patients in surgery for cervical myelopathy, involving 21 with cervical spondylosis and 10 with ossification of the posterior longitudinal ligamentum, and compared the findings from those with a poor outcome (n=3l) with the findings from those with a good outcome (n=32). The MEPs from the thenar muscle and the tibialis anterior were evoked by transcranial magnetic brain stimulation. In the poor-outcome patients, the spinal canal was narrow and lumbar spinal canal stenosis was seen in 5 cases which required lumbar laminectomy. Before operation, the MEPs from the thenar muscle could not be evoked in 5 cases while there was a remarkably prolonged central motor conduction time in the other 26 cases. MRI revealed the deformed spinal cord in the involved area, and the signal intensity of the involved spinal cord in the T2 weighted image was remarkably high. The signal intensity ratio was significantly higher in the poor-outcome patients than in the good-outcome patients. This study suggested that a high signal intensity in the T2 weighted image and a prolonged conduction time or absence of MEPs largely corresponded to the clinical and other investigative features of myelopathy responsible for a poor outcome. (author).

  18. Electrophysiological and MRI study on poor outcome after surgery for cervical myelopathy

    International Nuclear Information System (INIS)

    Kameyama, Osamu; Kawakita, Hirofumi; Ogawa, Ryokei

    1995-01-01

    Occasionally, the outcome from laminoplasty for cervical spondylosis is disappointing despite an adequate operation. Before surgery, it is difficult to diagnose the pathological extent of the involvement of the spinal cord. The purpose of this study is to determine the efficacy of magnetic resonance imaging (MRI) and of the motor evoked potentials (MEPs) for the indication of the surgery and prognosis. Retrospectively, we investigated the MEPs and the MRI of 31 patients in surgery for cervical myelopathy, involving 21 with cervical spondylosis and 10 with ossification of the posterior longitudinal ligamentum, and compared the findings from those with a poor outcome (n=3l) with the findings from those with a good outcome (n=32). The MEPs from the thenar muscle and the tibialis anterior were evoked by transcranial magnetic brain stimulation. In the poor-outcome patients, the spinal canal was narrow and lumbar spinal canal stenosis was seen in 5 cases which required lumbar laminectomy. Before operation, the MEPs from the thenar muscle could not be evoked in 5 cases while there was a remarkably prolonged central motor conduction time in the other 26 cases. MRI revealed the deformed spinal cord in the involved area, and the signal intensity of the involved spinal cord in the T2 weighted image was remarkably high. The signal intensity ratio was significantly higher in the poor-outcome patients than in the good-outcome patients. This study suggested that a high signal intensity in the T2 weighted image and a prolonged conduction time or absence of MEPs largely corresponded to the clinical and other investigative features of myelopathy responsible for a poor outcome. (author)

  19. Short-term evolution of spinal cord damage in multiple sclerosis: a diffusion tensor MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Theaudin, M.; Denier, C.; Adams, D. [AP-HP, CHU Bicetre, Service de Neurologie Adultes, Le Kremlin-Bicetre (France); INSERM, UMR788, Faculte de Medecine Paris Sud, Le Kremlin-Bicetre (France); Saliou, G. [AP-HP, CHU Bicetre, Service de Neuroradiologie, Le Kremlin-Bicetre (France); Ducot, B. [INSERM, U1018, CESP Centre for Research in Epidemiology and Population Health, Faculte de Medecine Paris Sud, Le Kremlin-Bicetre (France); Deiva, K. [Service de Neuropediatrie, Le Kremlin-Bicetre (France); Ducreux, D. [INSERM, UMR788, Faculte de Medecine Paris Sud, Le Kremlin-Bicetre (France); AP-HP, CHU Bicetre, Service de Neuroradiologie, Le Kremlin-Bicetre (France)

    2012-10-15

    The potential of diffusion tensor imaging (DTI) to detect spinal cord abnormalities in patients with multiple sclerosis has already been demonstrated. The objective of this study was to apply DTI techniques to multiple sclerosis patients with a recently diagnosed spinal cord lesion, in order to demonstrate a correlation between variations of DTI parameters and clinical outcome, and to try to identify DTI parameters predictive of outcome. A prospective single-centre study of patients with spinal cord relapse treated by intravenous steroid therapy was made. Patients were assessed clinically and by conventional MRI with DTI sequences at baseline and at 3 months. Sixteen patients were recruited. At 3 months, 12 patients were clinically improved. All but one patient had lower fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values than normal subjects in either inflammatory lesions or normal-appearing spinal cord. Patients who improved at 3 months presented a significant reduction in the radial diffusivity (p = 0.05) in lesions during the follow-up period. They also had a significant reduction in the mean ADC (p = 0.002), axial diffusivity (p = 0.02), radial diffusivity (p = 0.02) and a significant increase in FA values (p = 0.02) in normal-appearing spinal cord. Patients in whom the American Spinal Injury Association sensory score improved at 3 months showed a significantly higher FA (p = 0.009) and lower radial diffusivity (p = 0.04) in inflammatory lesion at baseline compared to patients with no improvement. DTI MRI detects more extensive abnormalities than conventional T2 MRI. A less marked decrease in FA value and more marked decreased in radial diffusivity inside the inflammatory lesion were associated with better outcome. (orig.)

  20. Short-term evolution of spinal cord damage in multiple sclerosis: a diffusion tensor MRI study

    International Nuclear Information System (INIS)

    Theaudin, M.; Denier, C.; Adams, D.; Saliou, G.; Ducot, B.; Deiva, K.; Ducreux, D.

    2012-01-01

    The potential of diffusion tensor imaging (DTI) to detect spinal cord abnormalities in patients with multiple sclerosis has already been demonstrated. The objective of this study was to apply DTI techniques to multiple sclerosis patients with a recently diagnosed spinal cord lesion, in order to demonstrate a correlation between variations of DTI parameters and clinical outcome, and to try to identify DTI parameters predictive of outcome. A prospective single-centre study of patients with spinal cord relapse treated by intravenous steroid therapy was made. Patients were assessed clinically and by conventional MRI with DTI sequences at baseline and at 3 months. Sixteen patients were recruited. At 3 months, 12 patients were clinically improved. All but one patient had lower fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values than normal subjects in either inflammatory lesions or normal-appearing spinal cord. Patients who improved at 3 months presented a significant reduction in the radial diffusivity (p = 0.05) in lesions during the follow-up period. They also had a significant reduction in the mean ADC (p = 0.002), axial diffusivity (p = 0.02), radial diffusivity (p = 0.02) and a significant increase in FA values (p = 0.02) in normal-appearing spinal cord. Patients in whom the American Spinal Injury Association sensory score improved at 3 months showed a significantly higher FA (p = 0.009) and lower radial diffusivity (p = 0.04) in inflammatory lesion at baseline compared to patients with no improvement. DTI MRI detects more extensive abnormalities than conventional T2 MRI. A less marked decrease in FA value and more marked decreased in radial diffusivity inside the inflammatory lesion were associated with better outcome. (orig.)

  1. 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.

  2. 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.)

  3. 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.)

  4. Pilot study for supervised target detection applied to spatially registered multiparametric MRI in order to non-invasively score prostate cancer.

    Science.gov (United States)

    Mayer, Rulon; Simone, Charles B; Skinner, William; Turkbey, Baris; Choykey, Peter

    2018-03-01

    Gleason Score (GS) is a validated predictor of prostate cancer (PCa) disease progression and outcomes. GS from invasive needle biopsies suffers from significant inter-observer variability and possible sampling error, leading to underestimating disease severity ("underscoring") and can result in possible complications. A robust non-invasive image-based approach is, therefore, needed. Use spatially registered multi-parametric MRI (MP-MRI), signatures, and supervised target detection algorithms (STDA) to non-invasively GS PCa at the voxel level. This study retrospectively analyzed 26 MP-MRI from The Cancer Imaging Archive. The MP-MRI (T2, Diffusion Weighted, Dynamic Contrast Enhanced) were spatially registered to each other, combined into stacks, and stitched together to form hypercubes. Multi-parametric (or multi-spectral) signatures derived from a training set of registered MP-MRI were transformed using statistics-based Whitening-Dewhitening (WD). Transformed signatures were inserted into STDA (having conical decision surfaces) applied to registered MP-MRI determined the tumor GS. The MRI-derived GS was quantitatively compared to the pathologist's assessment of the histology of sectioned whole mount prostates from patients who underwent radical prostatectomy. In addition, a meta-analysis of 17 studies of needle biopsy determined GS with confusion matrices and was compared to the MRI-determined GS. STDA and histology determined GS are highly correlated (R = 0.86, p < 0.02). STDA more accurately determined GS and reduced GS underscoring of PCa relative to needle biopsy as summarized by meta-analysis (p < 0.05). This pilot study found registered MP-MRI, STDA, and WD transforms of signatures shows promise in non-invasively GS PCa and reducing underscoring with high spatial resolution. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Morphometric MRI changes in intracranial hypertension due to cerebral venous thrombosis: a retrospective imaging study

    International Nuclear Information System (INIS)

    Dong, Cheng; Zheng, Ying-mei; Li, Xiao-li; Wang, He-xiang; Hao, Da-peng; Nie, Pei; Pang, Jing; Xu, Wen-jian

    2016-01-01

    Aim: To evaluate whether some magnetic resonance imaging (MRI) signs suggesting idiopathic intracranial hypertension (IIH) could also be found in intracranial hypertension (IH) due to cerebral venous thrombosis (CVT) and to assess their possible contribution to diagnosing this disorder. Materials and methods: Thirty-one patients with IH due to CVT were evaluated prospectively using MRI. A group of 33 age- and sex-matched healthy volunteers served as controls. The optic nerve and sheath, pituitary gland, and ventricles were assessed. The prevalence of each imaging feature was compared between the two groups. Results: Optic nerve sheath (ONS) dilatation and decreased pituitary gland height were the most valid signs suggesting IH in CVT patients: sensitivity 70.97% and 87.1%, respectively; specificity 96.97% and 72.73%, respectively; area under the curve 0.840 and 0.809, respectively. The MRI finding that showed the strongest association with IH in CVT patients was ONS dilatation (odds ratio 78.5). Conclusions: The combination of T1-weighted volumetric MRI and magnetic resonance venography could be helpful for diagnosing IH with CVT. Abnormalities of the ONS and the pituitary gland were reliable diagnostic signs for IH due to CVT. - Highlights: • We compared the prevalence of MRI imaging features between IH patients due to CVT and healthy volunteers. • Several MRI imaging features occur more frequently in IH patients due to CVT. • Abnormalities of the ONS and the pituitary gland were reliable diagnostic signs for IH due to CVT.

  6. Framing deductive reasoning with emotional content: an fMRI study.

    Science.gov (United States)

    Brunetti, M; Perrucci, M G; Di Naccio, M R; Ferretti, A; Del Gratta, C; Casadio, C; Romani, G L

    2014-06-01

    In the literature concerning the study of emotional effect on cognition, several researches highlight the mechanisms of reasoning ability and the influence of emotions on this ability. However, up to now, no neuroimaging study was specifically devised to directly compare the influence on reasoning performance of visual task-unrelated with semantic task-related emotional information. In the present functional fMRI study, we devised a novel paradigm in which emotionally negative vs. neutral visual stimuli (context) were used as primes, followed by syllogisms composed of propositions with emotionally negative vs. neutral contents respectively. Participants, in the MR scanner, were asked to assess the logical validity of the syllogisms. We have therefore manipulated the emotional state and arousal induced by the visual prime as well as the emotional interference exerted by the syllogism content. fMRI data indicated a medial prefrontal cortex deactivation and lateral/dorsolateral prefrontal cortex activation in conditions with negative context. Furthermore, a lateral/dorsolateral prefrontal cortex modulation caused by syllogism content was observed. Finally, behavioral data confirmed the influence of emotional task-related stimuli on reasoning ability, since the performance was worse in conditions with syllogisms involving negative emotions. Therefore, on the basis of these data, we conclude that emotional states can impair the performance in reasoning tasks by means of the delayed general reactivity, whereas the emotional content of the target may require a larger amount of top-down resources to be processed. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Lying about the valence of affective pictures: an fMRI study.

    Directory of Open Access Journals (Sweden)

    Tatia M C Lee

    Full Text Available The neural correlates of lying about affective information were studied using a functional magnetic resonance imaging (fMRI methodology. Specifically, 13 healthy right-handed Chinese men were instructed to lie about the valence, positive or negative, of pictures selected from the International Affective Picture System (IAPS while their brain activity was scanned by a 3T Philip Achieva scanner. The key finding is that the neural activity associated with deception is valence-related. Comparing to telling the truth, deception about the valence of the affectively positive pictures was associated with activity in the inferior frontal, cingulate, inferior parietal, precuneus, and middle temporal regions. Lying about the valence of the affectively negative pictures, on the other hand, was associated with activity in the orbital and medial frontal regions. While a clear valence-related effect on deception was observed, common neural regions were also recruited for the process of deception about the valence of the affective pictures. These regions included the lateral prefrontal and inferior parietal regions. Activity in these regions has been widely reported in fMRI studies on deception using affectively-neutral stimuli. The findings of this study reveal the effect of valence on the neural activity associated with deception. Furthermore, the data also help to illustrate the complexity of the neural mechanisms underlying deception.

  8. 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.)

  9. Neural correlates of vocal learning in songbirds and humans: cross-species fMRI studies into individual differences

    OpenAIRE

    Kant, Anne Marie van der

    2015-01-01

    Animal models, songbirds particularly, are increasingly used to study the human capacity for speech and language. In the light of understanding both language evolution and individual language acquisition these models are highly valuable, provided that they are studied within a valid comparative framework. In the past few decades, non-invasive methods such as functional Magnetic Resonance Imaging (fMRI) and Near-InfraRed Spectroscopy (NIRS) have become available for human as well as animal bra...

  10. Comparative imaging study on monkeys with hemi-parkinsonism

    International Nuclear Information System (INIS)

    Wang Wei; Yu Xiaoping; Mao Jun; Liu Sheng; Wang Xiaoyi; Peng Guangchun; Wang Ruiwen

    2003-01-01

    Objective: To study the imaging appearance of experimental Parkinson's disease (PD) and to evaluate the different medical imaging exams on PD. Methods: CT, MRI, SPECT (dopamine transporter imaging and regional cerebral blood flow imaging, DAT imaging and rCBF imaging), and PET (glucose metabolism imaging) were performed on 8 monkeys before and after the infusion of MPTP into unilateral internal carotid artery to develop hemi-Parkinsonism models. Results: Hemi-Parkinsonism models were successfully induced on all 8 monkeys. On DAT imaging, the uptake values of the lesioned striatums decreased obviously after the MPTP treatment and were lower than that of the contralateral ones. The glucose metabolic rates of the lesioned striatums and thalamus in PD models were lower, compared to that of the healthy monkeys and that of the contralateral sides of themselves. Neither DAT nor glucose metabolism abnormalities was found on both the contralateral sides of the healthy and PD monkeys. On MRI images before MPTP treatment, only 4 of 8 PD models showed hypointense in bilateral globus pallidus. No abnormal MRI findings occurred in the first 2 months after injection of MPTP. At tile third month, hypointense appeared in globus pallidus of three monkeys. Enlarged hyposignal region in globus pallidus were found in three models. Of the above 6 monkeys, two appeared hypointense in putamina. Substantia nigra demonstrated no abnormalities before and after MPTP treatment. All rCBF and CT images were normal. Conclusion: The decreased density of DAT and decreased glucose metabolism on experimental PD can be showed early by DAT imaging and glucose metabolism imaging, MRI can show abnormal signal in the basal ganglia of PD but it is later than DAT and glucose metabolism imaging. CT and rCBF find no abnormality on PD

  11. 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 ...

  12. 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...

  13. Evaluation of MRI acquisition workflow with lean six sigma method: case study of liver and knee examinations.

    Science.gov (United States)

    Roth, Christopher J; Boll, Daniel T; Wall, Lisa K; Merkle, Elmar M

    2010-08-01

    The purpose of this investigation was to assess workflow for medical imaging studies, specifically comparing liver and knee MRI examinations by use of the Lean Six Sigma methodologic framework. The hypothesis tested was that the Lean Six Sigma framework can be used to quantify MRI workflow and to identify sources of inefficiency to target for sequence and protocol improvement. Audio-video interleave streams representing individual acquisitions were obtained with graphic user interface screen capture software in the examinations of 10 outpatients undergoing MRI of the liver and 10 outpatients undergoing MRI of the knee. With Lean Six Sigma methods, the audio-video streams were dissected into value-added time (true image data acquisition periods), business value-added time (time spent that provides no direct patient benefit but is requisite in the current system), and non-value-added time (scanner inactivity while awaiting manual input). For overall MRI table time, value-added time was 43.5% (range, 39.7-48.3%) of the time for liver examinations and 89.9% (range, 87.4-93.6%) for knee examinations. Business value-added time was 16.3% of the table time for the liver and 4.3% of the table time for the knee examinations. Non-value-added time was 40.2% of the overall table time for the liver and 5.8% for the knee examinations. Liver MRI examinations consume statistically significantly more non-value-added and business value-added times than do knee examinations, primarily because of respiratory command management and contrast administration. Workflow analyses and accepted inefficiency reduction frameworks can be applied with use of a graphic user interface screen capture program.

  14. Somatostatin receptor scintigraphy and magnetic resonance imaging in recurrent medullary thyroid carcinoma: A comparative study

    International Nuclear Information System (INIS)

    Doerr, U.; Wuerstlin, S.; Frank-Raue, K.; Raue, F.; Hehrmann, R.; Iser, G.; Scholz, M.; Guhl, L.; Buhr, H.J.; Bihl, H.

    1993-01-01

    In a prospective study, 18 patients with recurrent medullary thyroid carcinoma (MTC) underwent magnetic resonance imaging (MRI) of the neck and mediastinum and somatostatin receptor scintigraphy (SRS) with 111 In-labeled pentetreotide. In nine patients with macroscopic MTC, 17 corresponding lesions were found on MRI and SRS; in addition, 13 suspicious lesions were seen on SRS only. Histological confirmation was available for 19 metastatic lesions, showing MRI to be true positive in 13 metastases, SRS in 18. In minimal residual disease (n=10), MRI and SRS were compared with the histological findings in three patients and with selective venous catheterization (SVC) in seven patients. Corresponding findings on MRI and SVC were seen in one of seven, whereas SRS and SVC showed concordant localization of tumor recurrence in five of seven. Histological examination demonstrated MTC tissue in one of three cases; MRI and SRS were false positive in one of three cases, while in the others the interpretation remained uncertain. In conclusion, SRS is a promising imaging modality for localization of MTC recurrence. MRI provides better spatial resolution and thus facilitates the planning of surgery for macroscopic metastases. In minimal residual disease, SRS turned out to be superior in detecting occult MTC recurrence, confirming SVC findings. (orig.)

  15. Statistical analysis of MRI-only based dose planning

    DEFF Research Database (Denmark)

    Korsholm, M. E.; Waring, L. W.; Paulsen, Rasmus Reinhold

    2012-01-01

    . MRIonly based RT eliminates these errors and reduce the time and costs of a CT scan. The aim of this study is to investigate the dosimetric differences of a treatment plan when the dose calculation is based on MRI as compared to CT. Materials and Methods: Four diagnostic groups are investigated; 12...... as a clinically approved treatment plan. The treatment planning software is Eclipse v.10.0 (Varian Medical Systems). The dose calculation based on MRI data is evaluated in two different ways; a homogeneous density assigned MRI (MRI unit), where the entire body is assigned an HU equal to water and a heterogeneous...... density assigned MRI (MRI bulk) where in addition the CT segmented bone is transferred to the MRI and assigned an age dependent HU based on ICRU report 46. The CT based clinical treatment plan and structure set are registered to the corresponding MRI unit and MRI bulk. The body is outlined on both the MRI...

  16. Comparative study Beamnrc VS Pinnacle

    International Nuclear Information System (INIS)

    Moreno Reyes, J. C.; Macias Jaen, J.; Jimenez Ortega, E.

    2013-01-01

    Has been developed in JAVA a software application called JJGAMMA, capable of manipulating the environment BEAMNRC and Pinnacle output formats 3 , comfortable, fast and accurately. As particular application you can use to compare dose distributions (plans for treatments, checking fields for modeling and clinical accelerators Commissioner) using, as objective criteria, function or Gamma index. (Author)

  17. Paracetamol suppositories: a comparative study.

    Science.gov (United States)

    Cullen, S; Kenny, D; Ward, O C; Sabra, K

    1989-01-01

    Paracetamol suppositories in two different bases were given to children who had fever after operations. Plasma concentrations and the effect on temperature were compared. There was a significant correlation between peak plasma concentrations and maximum drop in temperature. A lipophilic base produced better results than a hydrophilic base. PMID:2817936

  18. Paracetamol suppositories: a comparative study.

    OpenAIRE

    Cullen, S; Kenny, D; Ward, O C; Sabra, K

    1989-01-01

    Paracetamol suppositories in two different bases were given to children who had fever after operations. Plasma concentrations and the effect on temperature were compared. There was a significant correlation between peak plasma concentrations and maximum drop in temperature. A lipophilic base produced better results than a hydrophilic base.

  19. Comparison study of positron emission tomography, X-ray CT and MRI in Parkinsonism with dementia

    International Nuclear Information System (INIS)

    Okada, Junichi; Peppard, R.; Calne, D.B.

    1989-01-01

    Brain atrophy and local cerebral metabolic rate of glucose (LCMR-glc) in Parkinson's disease with dementia and Parkinsonism-dementia complex (PDC) were studied using positron emission tomography (PET) with F-18-2-deoxy-2-fluoro-D-glucose, X-ray CT and magnetic resonance imaging (MRI). The group of Parkinson's disease with dementia (n=7) had a significantly decreased LCMR-glc in all regions when compared with the age-matched normal group. In the group of Parkinson's disease without dementia (n=6), LCMR-glc was also significantly lower than the control group, although it was higher than the group with associated dementia. Some of the normal aged persons had cortical atrophy. There was no correlation between LCMR-glc and cortical atrophy. Six Guamnian patients had PDC associated with amyotrophic lateral sclerosis (ALS), and four patients had it without ALS. LCMR-glc did not differ in the two groups. It was, however, significantly lower than that in 5 Guamanian and 10 Caucasian normal persons. The group of PDC had a noticeable cortical atrophy and ventricular dilatation, regardless of the presence or absence of ALS. There was correlation between decrease of LCMR-glc and cortical atrophy of the frontal, parietal and temporal lobes. Parkinson's disease and PDC were different from Alzheimer's disease in which a decreased LCMR-glc has been reported to be usually confined to the cerebral cortex. Cortical atrophy and ventricular dilatation were depicted on MRI and CT in the PDC group, but did not in the group of Parkinson's disease. PET was useful in the functional examination and both MRI and CT were useful in the anatomical examination of these diseases. (Namekawa, K)

  20. 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).

  1. Postmenopausal hormone therapy and subclinical cerebrovascular disease: the WHIMS-MRI Study.

    Science.gov (United States)

    Coker, L H; Hogan, P E; Bryan, N R; Kuller, L H; Margolis, K L; Bettermann, K; Wallace, R B; Lao, Z; Freeman, R; Stefanick, M L; Shumaker, S A

    2009-01-13

    The Women's Health Initiative Memory Study (WHIMS) hormone therapy (HT) trials reported that conjugated equine estrogen (CEE) with or without medroxyprogesterone acetate (MPA) increases risk for all-cause dementia and global cognitive decline. WHIMS MRI measured subclinical cerebrovascular disease as a possible mechanism to explain cognitive decline reported in WHIMS. We contacted 2,345 women at 14 WHIMS sites; scans were completed on 1,424 (61%) and 1,403 were accepted for analysis. The primary outcome measure was total ischemic lesion volume on brain MRI. Mean duration of on-trial HT or placebo was 4 (CEE+MPA) or 5.6 years (CEE-Alone) and scans were conducted an average of 3 (CEE+MPA) or 1.4 years (CEE-Alone) post-trial termination. Cross-sectional analysis of MRI lesions was conducted; general linear models were fitted to assess treatment group differences using analysis of covariance. A (two-tailed) critical value of alpha = 0.05 was used. In women evenly matched within trials at baseline, increased lesion volumes were significantly related to age, smoking, history of cardiovascular disease, hypertension, lower post-trial global cognition scores, and increased incident cases of on- or post-trial mild cognitive impairment or probable dementia. Mean ischemic lesion volumes were slightly larger for the CEE+MPA group vs placebo, except for the basal ganglia, but the differences were not significant. Women assigned to CEE-Alone had similar mean ischemic lesion volumes compared to placebo. Conjugated equine estrogen-based hormone therapy was not associated with a significant increase in ischemic brain lesion volume relative to placebo. This finding was consistent within each trial and in pooled analyses across trials.

  2. Comparison study of positron emission tomography, X-ray CT and MRI in Parkinsonism with dementia

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Junichi; Peppard, R; Calne, D B

    1989-05-01

    Brain atrophy and local cerebral metabolic rate of glucose (LCMR-glc) in Parkinson's disease with dementia and Parkinsonism-dementia complex (PDC) were studied using positron emission tomography (PET) with F-18-2-deoxy-2-fluoro-D-glucose, X-ray CT and magnetic resonance imaging (MRI). The group of Parkinson's disease with dementia (n=7) had a significantly decreased LCMR-glc in all regions when compared with the age-matched normal group. In the group of Parkinson's disease without dementia (n=6), LCMR-glc was also significantly lower than the control group, although it was higher than the group with associated dementia. Some of the normal aged persons had cortical atrophy. There was no correlation between LCMR-glc and cortical atrophy. Six Guamnian patients had PDC associated with amyotrophic lateral sclerosis (ALS), and four patients had it without ALS. LCMR-glc did not differ in the two groups. It was, however, significantly lower than that in 5 Guamanian and 10 Caucasian normal persons. The group of PDC had a noticeable cortical atrophy and ventricular dilatation, regardless of the presence or absence of ALS. There was correlation between decrease of LCMR-glc and cortical atrophy of the frontal, parietal and temporal lobes. Parkinson's disease and PDC were different from Alzheimer's disease in which a decreased LCMR-glc has been reported to be usually confined to the cerebral cortex. Cortical atrophy and ventricular dilatation were depicted on MRI and CT in the PDC group, but did not in the group of Parkinson's disease. PET was useful in the functional examination and both MRI and CT were useful in the anatomical examination of these diseases. (Namekawa, K).

  3. Comparison study of positron emission tomography, X-ray CT and MRI in Parkinsonism with dementia

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Junichi; Peppard, R.; Calne, D.B.

    1989-05-01

    Brain atrophy and local cerebral metabolic rate of glucose (LCMR-glc) in Parkinson's disease with dementia and Parkinsonism-dementia complex (PDC) were studied using positron emission tomography (PET) with F-18-2-deoxy-2-fluoro-D-glucose, X-ray CT and magnetic resonance imaging (MRI). The group of Parkinson's disease with dementia (n=7) had a significantly decreased LCMR-glc in all regions when compared with the age-matched normal group. In the group of Parkinson's disease without dementia (n=6), LCMR-glc was also significantly lower than the control group, although it was higher than the group with associated dementia. Some of the normal aged persons had cortical atrophy. There was no correlation between LCMR-glc and cortical atrophy. Six Guamnian patients had PDC associated with amyotrophic lateral sclerosis (ALS), and four patients had it without ALS. LCMR-glc did not differ in the two groups. It was, however, significantly lower than that in 5 Guamanian and 10 Caucasian normal persons. The group of PDC had a noticeable cortical atrophy and ventricular dilatation, regardless of the presence or absence of ALS. There was correlation between decrease of LCMR-glc and cortical atrophy of the frontal, parietal and temporal lobes. Parkinson's disease and PDC were different from Alzheimer's disease in which a decreased LCMR-glc has been reported to be usually confined to the cerebral cortex. Cortical atrophy and ventricular dilatation were depicted on MRI and CT in the PDC group, but did not in the group of Parkinson's disease. PET was useful in the functional examination and both MRI and CT were useful in the anatomical examination of these diseases. (Namekawa, K).

  4. 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

  5. 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

  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. Cerebral Blood Flow Measurement Using fMRI and PET: A Cross-Validation Study

    Directory of Open Access Journals (Sweden)

    Jean J. Chen

    2008-01-01

    Full Text Available An important aspect of functional magnetic resonance imaging (fMRI is the study of brain hemodynamics, and MR arterial spin labeling (ASL perfusion imaging has gained wide acceptance as a robust and noninvasive technique. However, the cerebral blood flow (CBF measurements obtained with ASL fMRI have not been fully validated, particularly during global CBF modulations. We present a comparison of cerebral blood flow changes (ΔCBF measured using a flow-sensitive alternating inversion recovery (FAIR ASL perfusion method to those obtained using H2O15 PET, which is the current gold standard for in vivo imaging of CBF. To study regional and global CBF changes, a group of 10 healthy volunteers were imaged under identical experimental conditions during presentation of 5 levels of visual stimulation and one level of hypercapnia. The CBF changes were compared using 3 types of region-of-interest (ROI masks. FAIR measurements of CBF changes were found to be slightly lower than those measured with PET (average ΔCBF of 21.5±8.2% for FAIR versus 28.2±12.8% for PET at maximum stimulation intensity. Nonetheless, there was a strong correlation between measurements of the two modalities. Finally, a t-test comparison of the slopes of the linear fits of PET versus ASL ΔCBF for all 3 ROI types indicated no significant difference from unity (P>.05.

  8. Counterfactual thinking: an fMRI study on changing the past for a better future

    Science.gov (United States)

    Ma, Ning; Ampe, Lisa; Baetens, Kris; Van Overwalle, Frank

    2013-01-01

    Recent studies suggest that a brain network mainly associated with episodic memory has a more general function in imagining oneself in another time, place or perspective (e.g. episodic future thought, theory of mind, default mode). If this is true, counterfactual thinking (e.g. ‘If I had left the office earlier, I wouldn’t have missed my train.’) should also activate this network. Present functional magnetic resonance imaging (fMRI) study explores the common and distinct neural activity of counterfactual and episodic thinking by directly comparing the imagining of upward counterfactuals (creating better outcomes for negative past events) with the re-experiencing of negative past events and the imagining of positive future events. Results confirm that episodic and counterfactual thinking share a common brain network, involving a core memory network (hippocampal area, temporal lobes, midline, and lateral parietal lobes) and prefrontal areas that might be related to mentalizing (medial prefrontal cortex) and performance monitoring (right prefrontal cortex). In contrast to episodic past and future thinking, counterfactual thinking recruits some of these areas more strongly and extensively, and additionally activates the bilateral inferior parietal lobe and posterior medial frontal cortex. We discuss these findings in view of recent fMRI evidence on the working of episodic memory and theory of mind. PMID:22403155

  9. Anterior temporal white matter lesions in myotonic dystrophy with intellectual impairment: an MRI and neuropathological study

    International Nuclear Information System (INIS)

    Ogata, A.; Tashiro, K.; Terae, S.; Fujita, M.

    1998-01-01

    We studied 12 patients with myotonic dystrophy using MRI and the Mini-mental state examination (MMSE), to see it specific MRI findings were associated with intellectual impairment. We also compared them with the neuropathological findings in an autopsy case of MD with intellectual impairment. Mild intellectual impairment was found in 8 of the 12 patients. On T 2-weighted and proton density-weighted images, high-intensity areas were seen in cerebral white matter in 10 of the 12 patients. In seven of these, anterior temporal white-matter lesions (ATWML) were found; all seven had mild intellectual impairment (MMSE 22-26), whereas none of the four patients with normal mentation had ATWML. In only one of the eight patients with intellectual impairment were white-matter lesions not found. Pathological findings were severe loss and disordered arrangement of myelin sheaths and axons in addition to heterotopic neurons within anterior temporal white matter. Bilateral ATWML might be a factor for intellectual impairment in MD. The retrospective pathological study raised the possibility that the ATWML are compatible with focal dysplasia of white matter. (orig.)

  10. Altered spontaneous brain activity in patients with hemifacial spasm: a resting-state functional MRI study.

    Directory of Open Access Journals (Sweden)

    Ye Tu

    Full Text Available Resting-state functional magnetic resonance imaging (fMRI has been used to detect the alterations of spontaneous neuronal activity in various neurological and neuropsychiatric diseases, but rarely in hemifacial spasm (HFS, a nervous system disorder. We used resting-state fMRI with regional homogeneity (ReHo analysis to investigate changes in spontaneous brain activity of patients with HFS and to determine the relationship of these functional changes with clinical features. Thirty patients with HFS and 33 age-, sex-, and education-matched healthy controls were included in this study. Compared with controls, HFS patients had significantly decreased ReHo values in left middle frontal gyrus (MFG, left medial cingulate cortex (MCC, left lingual gyrus, right superior temporal gyrus (STG and right precuneus; and increased ReHo values in left precentral gyrus, anterior cingulate cortex (ACC, right brainstem, and right cerebellum. Furthermore, the mean ReHo value in brainstem showed a positive correlation with the spasm severity (r = 0.404, p = 0.027, and the mean ReHo value in MFG was inversely related with spasm severity in HFS group (r = -0.398, p = 0.028. This study reveals that HFS is associated with abnormal spontaneous brain activity in brain regions most involved in motor control and blinking movement. The disturbances of spontaneous brain activity reflected by ReHo measurements may provide insights into the neurological pathophysiology of HFS.

  11. 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.)

  12. 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.)

  13. 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)

  14. 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

  15. 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.

  16. 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.)

  17. 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)

  18. 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)

  19. 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

  20. Are batterers different from other criminals? An fMRI study

    Science.gov (United States)

    Verdejo-Román, Juan; Contreras-Rodríguez, Oren; Carmona-Perera, Martina; Pérez-García, Miguel; Hidalgo-Ruzzante, Natalia

    2016-01-01

    Abstract Intimate partner violence (IPV) is a complex and global phenomenon that requires a multi-perspective analysis. Nevertheless, the number of neuroscientific studies conducted on this issue is scarce as compared with studies of other types of violence, and no neuroimaging studies comparing batterers to other criminals have been conducted. Thus, the main aim of this study was to compare the brain functioning of batterers to that of other criminals when they are exposed to IPV or general violence pictures. An fMRI study was conducted in 21 batterers and 20 other criminals while they observed IPV images (IPVI), general violence images (GVI) and neutral images (NI). Results demonstrated that batterers, compared with other criminals, exhibited a higher activation in the anterior and posterior cingulate cortex and in the middle prefrontal cortex and a decreased activation in the superior prefrontal cortex to IPVI compared to NI. The paired t-test comparison between IPVI and GVI for each group showed engagement of the medial prefrontal cortex, the posterior cingulate and the left angular cortices to IPVI in the batterer group only. These results could have important implications for a better understanding of the IPV phenomenon. PMID:26884544

  1. 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.

  2. 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 ...

  3. Comparing three-dimensional serial optical coherence tomography histology to MRI imaging in the entire mouse brain

    Science.gov (United States)

    Castonguay, Alexandre; Lefebvre, Joël; Pouliot, Philippe; Lesage, Frédéric

    2018-01-01

    An automated serial histology setup combining optical coherence tomography (OCT) imaging with vibratome sectioning was used to image eight wild type mouse brains. The datasets resulted in thousands of volumetric tiles resolved at a voxel size of (4.9×4.9×6.5) μm3 stitched back together to give a three-dimensional map of the brain from which a template OCT brain was obtained. To assess deformation caused by tissue sectioning, reconstruction algorithms, and fixation, OCT datasets were compared to both in vivo and ex vivo magnetic resonance imaging (MRI) imaging. The OCT brain template yielded a highly detailed map of the brain structure, with a high contrast in white matter fiber bundles and was highly resemblant to the in vivo MRI template. Brain labeling using the Allen brain framework showed little variation in regional brain volume among imaging modalities with no statistical differences. The high correspondence between the OCT template brain and its in vivo counterpart demonstrates the potential of whole brain histology to validate in vivo imaging.

  4. Temporal lobe epilepsy with varying severity: MRI study of 222 patients

    International Nuclear Information System (INIS)

    Lehericy, S.; Hasboun, D.; Dormont, D.; Marsault, C.; Semah, F.; Baulac, M.; Clemenceau, S.; Granat, O.

    1997-01-01

    MRI was performed in 222 consecutive adult patients with temporal lobe epilepsy of varying severity from January 1991 to May 1993. The diagnosis of hippocampal sclerosis was established visually by three independent observers. The accuracy of visual assessment of hippocampal asymmetry was compared with volumetric measurements. Neuropathological correlations were obtained in 63 patients with refractory seizures. Temporal lobe abnormalities were observed in 180 patients (81 %) as follows: hippocampal sclerosis in 122 (55 %); developmental abnormalities in 16 (7.2 %); tumours in 15 (6.8 %); scars in 11 (5 %); cavernous angiomas in 10 (4.5 %); miscellaneous lesions in 6. MRI was normal or showed unrelated changes in 42 patients (19 %). Visual assessment correctly lateralised hippocampal sclerosis in 79 of the 84 patients measured (94 %). Temporal lobectomy confirmed the MRI data (side and aetiology) in all 63 operated patients. Patients with normal MRI had an older age of seizure onset and were more often drug-responsive than patients with hippocampal sclerosis. MRI showed temporal lobe abnormalities in 81 % of epileptic patients with varying severity with good neuropathological correlation. Patients with normal MRI had a less severe form of the disease. (orig.)

  5. Alveolar Echinococcosis of the Liver: Correlative Color Doppler US, CT, and MRI Study

    International Nuclear Information System (INIS)

    Cokun, A.; Oeztuerk, M.; Karahan, O.I.; Erdogan, N.; Ikin, S.; Guelec, M.

    2004-01-01

    Purpose: To determine and compare the imaging features of hepatic alveolar Echinococcosis using color Doppler US, CT, and MRI. Material and Methods: Abdominal CT and MRI with and without contrast agents and color Doppler US were performed on seven patients with hepatic alveolar Echinococcosis. The lesions were evaluated for location, features of echogenicity, intensity and density, calcification, and vascular, hilar, and perihepatic involvement. The diagnosis was confirmed histopathologically in all patients. Results: Six patients had solitary lesions, and one displayed multiple lesions. The lesions were generally seen as heterogeneous and hyper- or hypoechoic when imaged with color Doppler US, hypodense with CT, and hypointense with MRI, in comparison with the liver parenchyma. Calcification, central necrosis, and small peripheral cysts were observed in six, seven, and four patients, respectively. Vascular flow or contrast enhancement was not observed in any of the cases. A look at the respective advantages of each method reveals that calcification was best rendered visible via CT, small peripheral cysts with T2-weighted MRI, central necrosis with CT and MRI, and perihepatic invasion with multiplanar MRI. Vascular involvement was revealed by all methods. Conclusion: Color Doppler US, CT, and MR imaging function extremely well as complementary methods in the diagnosis of HAE. Color Doppler US should be performed in these patients owing to its ability to efficiently detect the disease. Knowledge of imaging characteristics makes it possible to radiologically ascertain an early diagnosis

  6. PET/MRI of metabolic activity in osteoarthritis: A feasibility study.

    Science.gov (United States)

    Kogan, Feliks; Fan, Audrey P; McWalter, Emily J; Oei, Edwin H G; Quon, Andrew; Gold, Garry E

    2017-06-01

    To evaluate positron emission tomography / magnetic resonance imaging (PET/MRI) knee imaging to detect and characterize osseous metabolic abnormalities and correlate PET radiotracer uptake with osseous abnormalities and cartilage degeneration observed on MRI. Both knees of 22 subjects with knee pain or injury were scanned at one timepoint, without gadolinium, on a hybrid 3.0T PET-MRI system following injection of 18 F-fluoride or 18 F-fluorodeoxyglucose (FDG). A musculoskeletal radiologist identified volumes of interest (VOIs) around bone abnormalities on MR images and scored bone marrow lesions (BMLs) and osteophytes using a MOAKS scoring system. Cartilage appearance adjacent to bone abnormalities was graded with MRI-modified Outerbridge classifications. On PET standardized uptake values (SUV) maps, VOIs with SUV greater than 5 times the SUV in normal-appearing bone were identified as high-uptake VOI (VOI High ). Differences in 18 F-fluoride uptake between bone abnormalities, BML, and osteophyte grades and adjacent cartilage grades on MRI were identified using Mann-Whitney U-tests. SUV max in all subchondral bone lesions (BML, osteophytes, sclerosis) was significantly higher than that of normal-appearing bone on MRI (P subchondral bone on MRI. Furthermore, many small grade 1 osteophytes (40 of 82 [49%]), often described as the earliest signs of osteoarthritis (OA), did not show high uptake. Lastly, PET SUV max in subchondral bone adjacent to grade 0 cartilage was significantly lower compared to that of grades 1-2 (P subchondral bone, which appear normal on MRI. 2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;45:1736-1745. © 2016 International Society for Magnetic Resonance in Medicine.

  7. Comprehensive imaging of tumor recurrence in breast cancer patients using whole-body MRI at 1.5 and 3 T compared to FDG-PET-CT

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Gerwin P. [Institute of Clinical Radiology, University Hospitals Munich-Grosshadern, Marchioninistr. 15, 81377 Munich (Germany)], E-mail: gerwin.schmidt@med.uni-muenchen.de; Baur-Melnyk, Andrea [Institute of Clinical Radiology, University Hospitals Munich-Grosshadern, Marchioninistr. 15, 81377 Munich (Germany); Haug, Alexander [Department of Nuclear Medicine, University Hospitals Munich-Grosshadern, 81377 Munich (Germany); Heinemann, Volker [Department of Internal Medicine III, University Hospitals Munich-Grosshadern, 81377 Munich (Germany); Bauerfeind, Ingo [Department of Obstetrics and Gynecology, University Hospitals Munich-Grosshadern, 81377 Munich (Germany); Reiser, Maximilian F. [Institute of Clinical Radiology, University Hospitals Munich-Grosshadern, Marchioninistr. 15, 81377 Munich (Germany); Schoenberg, Stefan O. [Institute of Clinical Radiology University Hospital Mannheim, Medical Faculty Mannheim, University of Heidelberg (Germany)

    2008-01-15

    Purpose: To compare the diagnostic accuracy for the detection of tumor recurrence in breast cancer patients using whole-body-MRI (WB-MRI) at 1.5 or 3 T compared to FDG-PET-CT. Materials and methods: Thirty-three female patients with breast cancer and suspicion of recurrence underwent FDG-PET-CT and WB-MRI. Coronal T1w-TSE- and STIR-sequences, HASTE-imaging of the lungs, contrast-enhanced T1w- and T2w-TSE-sequences of the liver, brain and abdomen were performed, using a WB-MRI-scanner at 1.5 (n = 23) or 3 T (n = 10). Presence of local recurrence, lymph node involvement and distant metastatic disease was assessed using clinical and radiological follow-up as a standard of reference. Results: Tumor recurrence was found in 20 of 33 patients. Overall 186 malignant foci were detected with WB-MRI and PET-CT. Both modalities revealed two recurrent tumors of the breast. PET-CT detected more lymph node metastases (n = 21) than WB-MRI (n = 16). WB-MRI was more precise in the detection of distant metastases (n = 154 versus n = 147). Sensitivity was 93% (172/186) and 91% (170/186) for WB-MRI and PET-CT, specificity was 86% (66/77) and 90% (69/77), respectively. Examination times for WB-MRI at 1.5 and 3 T were 51 and 43 min, respectively, examination time for PET-CT was 103 min. Conclusion: WB-MRI and PET-CT are useful for the detection of tumor recurrence in the follow-up of breast cancer. WB-MRI is highly sensitive to distant metastatic disease. PET-CT is more sensitive in detecting lymph node involvement. Tumor screening with WB-MRI is feasible at 1.5 and 3 T, scan time is further reduced at 3 T with identical resolution.

  8. Stress examination of flexor tendon pulley rupture in the crimp grip position: a 1.5-Tesla MRI cadaver study

    Energy Technology Data Exchange (ETDEWEB)

    Bayer, Thomas; Janka, Rolf [University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Fries, Simon [Cantonal Hospital Lucerne, Orthopaedic Department, Wolhusen (Switzerland); Schweizer, Andreas [University of Zurich, Department of Orthopaedics, Balgrist, Zurich (Switzerland); Schoeffl, Isabelle [Klinikum Bamberg, Department of Pediatrics, Bamberg (Germany); Bongartz, Georg [University Basel, Department of Radiology, Basel (Switzerland)

    2015-01-15

    The objectives of this study were the evaluation of flexor tendon pulley rupture of the fingers in the crimp grip position using magnetic resonance imaging (MRI) and the comparison of the results with MRI in the neutral position in a cadaver study. MRI in the crimp grip position and in the neutral position was performed in 21 cadaver fingers with artificially created flexor tendon pulley tears (combined pulley rupture, n = 14; single pulley rupture, n = 7). Measurement of the distance between the tendon and bone was performed. Images were evaluated by two readers, first independently and in cases of discrepancy in consensus. Sensitivity and specificity for detecting combined pulley ruptures were calculated. Tendon bone distances were significantly higher in the crimp grip position than in the neutral position. Sensitivity and specificity for detecting combined pulley rupture were 92.86 % and 100 % respectively in the crimp grip position and 78.57 % and 85.71 % respectively in the neutral position. Kappa values for interobserver reliability were 0.87 in the crimp grip position and 0.59 in the neutral position. MRI examination in the crimp grip position results in higher tendon bone distances by subjecting the pulleys to a higher strain, which facilitates image evaluation with higher interobserver reliability, higher sensitivity, and higher specificity for combined pulley rupture compared with examination in the neutral position. (orig.)

  9. Hypoactivation of the primary sensorimotor cortex in de novo Parkinson's disease. A motor fMRI study under controlled conditions

    International Nuclear Information System (INIS)

    Tessa, Carlo; Vignali, Claudio; Lucetti, Claudio; Diciotti, Stefano; Paoli, Lorenzo; Ginestroni, Andrea; Mascalchi, Mario; Cecchi, Paolo; Baldacci, Filippo; Giannelli, Marco; Bonuccelli, Ubaldo

    2012-01-01

    Nuclear medicine studies in Parkinson's disease (PD) indicate that nigrostriatal damage causes a widespread cortical hypoactivity assumed to be due to reduced excitatory thalamic outflow. However, so far, functional MRI (fMRI) studies have provided controversial data about this ''functional deafferentation'' phenomenon. To further clarify this issue, we assessed, with fMRI, de novo drug-naive PD patients using a relatively complex motor task under strictly controlled conditions. Nineteen de novo PD patients with right-predominant or bilateral symptoms and 13 age-matched healthy volunteers performed continuous writing of ''8'' figures with the right-dominant hand using a MR-compatible device that enables identification of incorrectly performed tasks and measures the size and the frequency of the ''8''s. The data were analyzed with FSL software and correlated with the clinical severity rated according to the Hoehn and Yahr (HY) staging system. Fifteen (89%) of 19 PD patients and 12 (92%) of 13 controls correctly executed the task. PD patients showed significant hypoactivation of the left primary sensorimotor cortex (SM1) and cerebellum and no hyperactive areas as compared to controls. However, activation in SM1 and supplementary motor area bilaterally, in left supramarginal, parietal inferior, parietal superior and frontal superior gyri as well as in right parietal superior and angular gyri paralleled increasing disease severity as assessed with the HY stage. In line with the ''deafferentation hypothesis'', fMRI demonstrates hypoactivation of the SM1 in the early clinical stage of PD. (orig.)

  10. 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.

  11. 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...

  12. 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...

  13. 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

  14. Using Edge Voxel Information to Improve Motion Regression for rs-fMRI Connectivity Studies.

    Science.gov (United States)

    Patriat, Rémi; Molloy, Erin K; Birn, Rasmus M

    2015-11-01

    Recent fMRI studies have outlined the critical impact of in-scanner head motion, particularly on estimates of functional connectivity. Common strategies to reduce the influence of motion include realignment as well as the inclusion of nuisance regressors, such as the 6 realignment parameters, their first derivatives, time-shifted versions of the realignment parameters, and the squared parameters. However, these regressors have limited success at noise reduction. We hypothesized that using nuisance regressors consisting of the principal components (PCs) of edge voxel time series would be better able to capture slice-specific and nonlinear signal changes, thus explaining more variance, improving data quality (i.e., lower DVARS and temporal SNR), and reducing the effect of motion on default-mode network connectivity. Functional MRI data from 22 healthy adult subjects were preprocessed using typical motion regression approaches as well as nuisance regression derived from edge voxel time courses. Results were evaluated in the presence and absence of both global signal regression and motion censoring. Nuisance regressors derived from signal intensity time courses at the edge of the brain significantly improved motion correction compared to using only the realignment parameters and their derivatives. Of the models tested, only the edge voxel regression models were able to eliminate significant differences in default-mode network connectivity between high- and low-motion subjects regardless of the use of global signal regression or censoring.

  15. 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.

  16. Functional network centrality in obesity: A resting-state and task fMRI study.

    Science.gov (United States)

    García-García, Isabel; Jurado, María Ángeles; Garolera, Maite; Marqués-Iturria, Idoia; Horstmann, Annette; Segura, Bàrbara; Pueyo, Roser; Sender-Palacios, María José; Vernet-Vernet, Maria; Villringer, Arno; Junqué, Carme; Margulies, Daniel S; Neumann, Jane

    2015-09-30

    Obesity is associated with structural and functional alterations in brain areas that are often functionally distinct and anatomically distant. This suggests that obesity is associated with differences in functional connectivity of regions distributed across the brain. However, studies addressing whole brain functional connectivity in obesity remain scarce. Here, we compared voxel-wise degree centrality and eigenvector centrality between participants with obesity (n=20) and normal-weight controls (n=21). We analyzed resting state and task-related fMRI data acquired from the same individuals. Relative to normal-weight controls, participants with obesity exhibited reduced degree centrality in the right middle frontal gyrus in the resting-state condition. During the task fMRI condition, obese participants exhibited less degree centrality in the left middle frontal gyrus and the lateral occipital cortex along with reduced eigenvector centrality in the lateral occipital cortex and occipital pole. Our results highlight the central role of the middle frontal gyrus in the pathophysiology of obesity, a structure involved in several brain circuits signaling attention, executive functions and motor functions. Additionally, our analysis suggests the existence of task-dependent reduced centrality in occipital areas; regions with a role in perceptual processes and that are profoundly modulated by attention. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Impaired neural networks for approximate calculation in dyscalculic children: a functional MRI study

    Directory of Open Access Journals (Sweden)

    Dosch Mengia

    2006-09-01

    Full Text Available Abstract Background Developmental dyscalculia (DD is a specific learning disability affecting the acquisition of mathematical skills in children with otherwise normal general intelligence. The goal of the present study was to examine cerebral mechanisms underlying DD. Methods Eighteen children with DD aged 11.2 ± 1.3 years and twenty age-matched typically achieving schoolchildren were investigated using functional magnetic resonance imaging (fMRI during trials testing approximate and exact mathematical calculation, as well as magnitude comparison. Results Children with DD showed greater inter-individual variability and had weaker activation in almost the entire neuronal network for approximate calculation including the intraparietal sulcus, and the middle and inferior frontal gyrus of both hemispheres. In particular, the left intraparietal sulcus, the left inferior frontal gyrus and the right middle frontal gyrus seem to play crucial roles in correct approximate calculation, since brain activation correlated with accuracy rate in these regions. In contrast, no differences between groups could be found for exact calculation and magnitude comparison. In general, fMRI revealed similar parietal and prefrontal activation patterns in DD children compared to controls for all conditions. Conclusion In conclusion, there is evidence for a deficient recruitment of neural resources in children with DD when processing analog magnitudes of numbers.

  18. MRI study on the cortical thickness of occipital lobe in children with ametropic amblyopia

    International Nuclear Information System (INIS)

    Du Hanjian; Wang Jian; Li Chuan; Zhang Jiuquan; Chen Li; Liu Bo

    2008-01-01

    Objective: To study cortical thickness of the occipital lobe in children with ametropic amblyopia by using MRI technique and the FreeSurfer software. Methods: Nine children with ametropic amblyopia were included in the amblyopic group and 8 normal children were included in the control group. All the children underwent brain MRI on the Siemens Avanto 1.5 T scanner. For the cortical thickness analysis, 3-demensional MPRAGE images were collected and analyzed with FreeSurfer software package. Cortical thickness of related regions in the occipital lobe (including the cuneus, later occipital, lingual, and pericalcarine gyri) were recorded and compared. Results: The cortical thickness of the lingual, pericalcarine gyri on the left hemisphere and the cuneus, lateraloccipital, lingual gyri on the right hemisphere in amblyopic group were lower than the control group (P<0.05). Conclusion: Morphological changes existed in the occipital lobe in ametropic amblyopic children. The analysis technique with the FreeSurfer package has a potential value in the clinical application. (authors)

  19. Gender differences in the cognitive control of emotion: An fMRI study.

    Science.gov (United States)

    Koch, Kathrin; Pauly, Katharina; Kellermann, Thilo; Seiferth, Nina Y; Reske, Martina; Backes, Volker; Stöcker, Tony; Shah, N Jon; Amunts, Katrin; Kircher, Tilo; Schneider, Frank; Habel, Ute

    2007-09-20

    The interaction of emotion and cognition has become a topic of major interest. However, the influence of gender on the interplay between the two processes, along with its neural correlates have not been fully analysed so far. In this functional magnetic resonance imaging (fMRI) study we induced negative emotion using negative olfactory stimulation while male (n=21) and female (n=19) participants performed an n-back verbal working memory task. Based on findings indicating increased emotional reactivity in women, we expected the female participants to exhibit stronger activation in characteristically emotion-associated areas during the interaction of emotional and cognitive processing in comparison to the male participants. Both groups were found to be significantly impaired in their working memory performance by negative emotion induction. However, fMRI analysis revealed distinct differences in neuronal activation between groups. In men, cognitive performance under negative emotion induction was associated with extended activation patterns in mainly prefrontal and superior parietal regions. In women, the interaction between emotion and working memory yielded a significantly stronger response in the amygdala and the orbitofrontal cortex (OFC) compared to their male counterparts. Our data suggest that in women the interaction of verbal working memory and negative emotion is associated with relative hyperactivation in more emotion-associated areas whereas in men regions commonly regarded as important for cognition and cognitive control are activated. These results provide new insights in gender-specific cerebral mechanisms.

  20. Gender differences in regional cerebral activity during the perception of emotion: a functional MRI study.

    Science.gov (United States)

    Hofer, Alex; Siedentopf, Christian M; Ischebeck, Anja; Rettenbacher, Maria A; Verius, Michael; Felber, Stephan; Fleischhacker, W Wolfgang

    2006-08-15

    Whether men activate different brain regions during various emotions compared to women or whether gender differences exist in transient emotional states has been the subject of only few studies. We used event-related functional magnetic resonance imaging (fMRI) to investigate gender differences during the perception of positive or negative emotions. The experiment comprised two emotional conditions (pleasant/unpleasant visual stimuli) during which fMRI data were acquired. Altogether, 38 healthy volunteers (19 males, 19 females) were investigated. When subtracting the activation values of men from those of women, suprathreshold positive signal changes were detected in the right posterior cingulate, the left putamen and the left cerebellum during positive mood induction, and in bilateral superior temporal gyri and cerebellar vermis during negative mood induction. The subtraction of activation values of women from those of men yielded no significant differences. Our findings suggest gender-related neural responses to emotional stimuli and could contribute to the understanding of mechanisms underlying gender-related vulnerability of the prevalence and severity of neuropsychiatric disorders.

  1. 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.)

  2. 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.

  3. 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

  4. 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.

  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. Posterior midline activation during symptom provocation in acute stress disorder: An fMRI study

    Directory of Open Access Journals (Sweden)

    Jan Christopher Cwik

    2014-05-01

    Full Text Available Functional imaging studies of patients with Posttraumatic Stress Disorder showed wide-spread activation of mid-line cortical areas during symptom provocation i.e., exposure to trauma-related cues. The present study aimed at investigating neural activation during exposure to trauma-related pictures in patients with Acute Stress Disorder (ASD shortly after the traumatic event. Nineteen ASD patients and 19 healthy control participants were presented with individualized pictures of the traumatic event and emotionally neutral control pictures during the acquisition of whole-brain data with a 3-T fMRI scanner. Compared to the control group and to control pictures, ASD patients showed significant activation in mid-line cortical areas in response to trauma-related pictures including precuneus, cuneus, postcentral gyrus and pre-supplementary motor area. The results suggest that the trauma-related pictures evoke emotionally salient self-referential processing in ASD patients.

  8. Reducing Individual Variation for fMRI Studies in Children by Minimizing Template Related Errors.

    Directory of Open Access Journals (Sweden)

    Jian Weng

    Full Text Available Spatial normalization is an essential process for group comparisons in functional MRI studies. In practice, there is a risk of normalization errors particularly in studies involving children, seniors or diseased populations and in regions with high individual variation. One way to minimize normalization errors is to create a study-specific template based on a large sample size. However, studies with a large sample size are not always feasible, particularly for children studies. The performance of templates with a small sample size has not been evaluated in fMRI studies in children. In the current study, this issue was encountered in a working memory task with 29 children in two groups. We compared the performance of different templates: a study-specific template created by the experimental population, a Chinese children template and the widely used adult MNI template. We observed distinct differences in the right orbitofrontal region among the three templates in between-group comparisons. The study-specific template and the Chinese children template were more sensitive for the detection of between-group differences in the orbitofrontal cortex than the MNI template. Proper templates could effectively reduce individual variation. Further analysis revealed a correlation between the BOLD contrast size and the norm index of the affine transformation matrix, i.e., the SFN, which characterizes the difference between a template and a native image and differs significantly across subjects. Thereby, we proposed and tested another method to reduce individual variation that included the SFN as a covariate in group-wise statistics. This correction exhibits outstanding performance in enhancing detection power in group-level tests. A training effect of abacus-based mental calculation was also demonstrated, with significantly elevated activation in the right orbitofrontal region that correlated with behavioral response time across subjects in the trained group.

  9. 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...

  10. MRI for the size assessment of pure ductal carcinoma in situ (DCIS): A prospective study of 33 patients

    International Nuclear Information System (INIS)

    Marcotte-Bloch, C.; Balu-Maestro, C.; Chamorey, E.; Ettore, F.; Raoust, I.; Flipo, B.; Chapellier, C.

    2011-01-01

    Objective: To determine whether MRI assesses the size of ductal carcinomas in situ (DCIS) more accurately than mammography, using the histopathological dimension of the surgical specimen as the reference measurement. Materials and methods: This single-center prospective study conducted from March 2007 to July 2008 at the Antoine-Lacassagne Cancer Treatment Center (Nice, France) included 33 patients with a histologically proven DCIS by needle biopsy, who all underwent clinical examination, mammography, and MRI interpreted by an experienced radiologist. All patients underwent surgery at our institution. The greatest dimensions of the DCIS determined by the two imaging modalities were compared with the histopathological dimension ascertained on the surgical specimen. The study was approved by the local Ethical Research Committee and was authorized by the French National Health Agency (AFSSAPS). Results: The mean age of the 33 patients was 59.7 years (±10.3). Three patients had a palpable mass at clinical breast examination; 82% underwent conservative surgical therapy rather than radical breast surgery (mastectomy); 6% required repeat surgery. MRI detected 97% of the lesions. Non-mass-like enhancement was noted for 78% of the patients. In over 50% of the cases, distribution of the DCIS was ductal or segmental and the kinetic enhancement curve was persistent. Lesion size was correctly estimated (±5 mm), under-estimated ( 5 mm), respectively, by MRI in 60%, 19% and 21% of cases and by mammography in 38%, 31% and 31% (p = 0.05). Mean lesion size was 25.6 mm at histopathology, 28.1 mm at MRI, and 27.2 mm on mammography (nonsignificant difference). The correlation coefficient between histopathological measurement and MRI was 0.831 versus 0.674 between histopathology and mammography. The correlation coefficient increased with the nuclear grade of the DCIS on mammography; this coefficient also increased as the mammographic breast density decreased. Conclusion: MRI appears

  11. Benchmarked Library Websites Comparative Study

    KAUST Repository

    Ramli, Rindra M.; Tyhurst, Janis

    2015-01-01

    This presentation provides an analysis of services provided by the benchmarked library websites. The exploratory study includes comparison of these websites against a list of criterion and presents a list of services that are most commonly deployed by the selected websites. In addition to that, the investigators proposed a list of services that could be provided via the KAUST library website.

  12. Patients with advanced Parkinson's disease with and without freezing of gait: a comparative analysis of vascular lesions using brain MRI.

    Science.gov (United States)

    Gallardo, M J; Cabello, J P; Pastor, C; Muñoz-Torrero, J J; Carrasco, S; Ibañez, R; Vaamonde, J

    2014-05-01

    Freezing of gait (FOG) is one of the most disabling and enigmatic symptoms in Parkinson's disease. Vascular lesions, observed in magnetic resonance imaging (MRI) scans, may produce or exacerbate this symptom. The study includes 22 patients with Parkinson's disease subjects, 12 with freezing of gait and 10 without. All patients underwent an MRI scan and any vascular lesions were analysed using the modified Fazekas scale. Patients with FOG scored higher on the modified Fazekas scale than the rest of the group. Although the two groups contained the same percentage of patients with vascular lesions (50% in both groups), lesion load was higher in the group of patients with FOG. Vascular lesions in the periventricular area and deep white matter seem to be the most involved in the development of FOG. Vascular lesions may contribute to the onset or worsening of FOG in patients with PD. This study suggests that cerebral vascular disease should be considered in patients with FOG. Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  13. 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.

  14. 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.)

  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