Evaluation of left ventricular volumes in patients with congenital heart disease and abnormal left ventricular geometry. Comparison of MRI and transthoracic 3-dimensional echocardiography

International Nuclear Information System (INIS)

Gutberlet, M.; Grothoff, M.; Roettgen, R.; Lange, P.; Felix, R.; Abdul-Khaliq, H.; Schroeter, J.; Schmitt, B.; Vogel, M.

2003-01-01

Purpose: To assess the new method of 3-dimensional echocardiography in comparison to the 'gold standard' MRI as to its ability to calculate left ventricular volumes in patients with congenital heart disease. Materials and methods: Eighteen patients between the ages of 3.9 to 37.3 years (mean: 12.8±9.7) with a geometrically abnormal left ventricle were examined using a 1.5 T scanner with a fast gradient-echo sequence (TR=14 ms, TE=2.6-2.9 ms, FOV=300-400 mm, flip angle=20 , matrix=128:256, slice thickness=5 mm, retrospective gating) in multislice-multiphase technique. Transthoracic 3D-echocardiography was performed with a 3.5 MHz transducer and a Tomtec trademark (Munich, Germany) system for 3D reconstruction. Results: Volume calculation was possible in all patients with 3D-echocardiography, but the muscle mass calculation only succeeded in 11 to 18 patients (61%) due to inadequate visualization of the entire myocardium. Comparing MRI and 3D-echocardiography, the correlation was r=0.97 for the end-systolic volumes, r=0.98 for the end-diastolic volumes, r=0.79 for the end-systolic muscle mass and r=0.77 for the end-diastolic muscle mass. The agreement between both methods was considered good for the calculated end-diastolic volumes and sufficient for the calculated end-systolic volumes. The muscle mass calculations showed larger differences especially for the end-systolic mass. Mean intraobserver variability was 18.6% for end-systolic and 8.3% for end-diastolic volumes. Conclusion: In patients with an abnormal left ventricular configuration due to congenital heart disease, the new method of 3D-echocardiography is sufficient for volume calculations in preselected patients. The high intraobserver variability is still a limitation of transthoracic 3D-echocardiography in comparison to MRI. (orig.) [de

MRI appearance of surgically proven abnormal accessory anterior-inferior tibiofibular ligament (Bassett's ligament)

International Nuclear Information System (INIS)

Subhas, Naveen; Vinson, Emily N.; Cothran, R.L.; Helms, Clyde A.; Santangelo, James R.; Nunley, James A.

2008-01-01

A thickened accessory anterior-inferior tibiofibular ligament (Bassett's ligament) of the ankle can be a cause of ankle impingement. Its imaging appearance is not well described. The purpose of this study was to determine if the ligament could be identified on magnetic resonance imaging (MRI), to determine associated abnormalities, and to determine if MRI could be used to differentiate normal from abnormal. Eighteen patients with a preoperative ankle MRI and an abnormal Bassett's ligament reported at surgery were found retrospectively. A separate cohort of 18 patients was selected as a control population. The presence of Bassett's ligament and its thickness were noted. The integrity and appearance of the lateral ankle ligaments, talar dome cartilage, and anterolateral gutter were also noted. In 34 of the 36 cases (94%), Bassett's ligament was identified on MRI. The ligament was seen in all three imaging planes and most frequently in the axial plane. The mean thickness of the ligament in the surgically abnormal cases was 2.37 mm, compared with 1.87 mm in the control with a p value = 0.015 (t test). Nine of the 18 abnormal cases (50%) had talar dome cartilage lesions as a result of contact with the ligament at surgery, with only 3 cases of high-grade defects seen on MRI. Fourteen of the 18 abnormal cases (78%) had of synovitis or scarring in the lateral gutter at surgery, with only 5 cases with scarring seen on MRI. The anterior-inferior tibiofibular ligament was abnormal or torn in 8 of the 18 abnormal cases (44%) by MRI and confirmed in only 3 cases at surgery. Bassett's ligament can be routinely identified on MRI and was significantly thicker in patients who had it resected at surgery. An abnormal Bassett's ligament is often present in the setting of a normal anterior-inferior tibiofibular ligament. The cartilage abnormalities and synovitis associated with an abnormal Bassett's ligament are poorly detected by conventional MRI. (orig.)

3D printing from MRI Data: Harnessing strengths and minimizing weaknesses.

Science.gov (United States)

Ripley, Beth; Levin, Dmitry; Kelil, Tatiana; Hermsen, Joshua L; Kim, Sooah; Maki, Jeffrey H; Wilson, Gregory J

2017-03-01

3D printing facilitates the creation of accurate physical models of patient-specific anatomy from medical imaging datasets. While the majority of models to date are created from computed tomography (CT) data, there is increasing interest in creating models from other datasets, such as ultrasound and magnetic resonance imaging (MRI). MRI, in particular, holds great potential for 3D printing, given its excellent tissue characterization and lack of ionizing radiation. There are, however, challenges to 3D printing from MRI data as well. Here we review the basics of 3D printing, explore the current strengths and weaknesses of printing from MRI data as they pertain to model accuracy, and discuss considerations in the design of MRI sequences for 3D printing. Finally, we explore the future of 3D printing and MRI, including creative applications and new materials. 5 J. Magn. Reson. Imaging 2017;45:635-645. © 2016 International Society for Magnetic Resonance in Medicine.

Creating 3D visualizations of MRI data: A brief guide

Science.gov (United States)

Madan, Christopher R.

2015-01-01

While magnetic resonance imaging (MRI) data is itself 3D, it is often difficult to adequately present the results papers and slides in 3D. As a result, findings of MRI studies are often presented in 2D instead. A solution is to create figures that include perspective and can convey 3D information; such figures can sometimes be produced by standard functional magnetic resonance imaging (fMRI) analysis packages and related specialty programs. However, many options cannot provide functionality such as visualizing activation clusters that are both cortical and subcortical (i.e., a 3D glass brain), the production of several statistical maps with an identical perspective in the 3D rendering, or animated renderings. Here I detail an approach for creating 3D visualizations of MRI data that satisfies all of these criteria. Though a 3D ‘glass brain’ rendering can sometimes be difficult to interpret, they are useful in showing a more overall representation of the results, whereas the traditional slices show a more local view. Combined, presenting both 2D and 3D representations of MR images can provide a more comprehensive view of the study’s findings. PMID:26594340

MRI abnormalities and related risk factors of the brain in patients with neuromyelitis optica

International Nuclear Information System (INIS)

Xiao Hui; Ma Lin; Lou Xin; Cai Youquan; Wang Yulin; Wang Yan; Wu Lei; Wu Weiping

2011-01-01

Objective: To investigate the MRI features of the brain in patients with neuromyelitis optica (NMO), and to evaluate the correlation between the brain abnormalities and related risk factors. Methods: Fifty-four patients with definite NMO according to 2006 Wingerchuk diagnosis criteria were enrolled in this study. MRI scanning of the brain was performed in these patients. Distribution and signal features of all the lesions were analyzed. A Logistic regression analysis was used to evaluate the risk factors of brain abnormalities. Results: Twenty-four NMO patients (44.4%) showed unremarkable findings and thirty (55.6%) showed abnormalities on brain MRI. Multiple and non-specific small lesions in the subcortical white matter and grey-white matter junction were the most frequent abnormalities on brain MRI (13/30, 43.3%). Typical lesion locations included corpus callosum, subependyma of ventricles, hypothalamus and brain stem. The lesions showed punctate, patchy and linear abnormal signals. Post-contrast MRI showed no abnormal enhancement in 16 cases. Logistic regression analysis showed that coexisting autoimmune disease or infection. history had correlations with abnormalities of the brain on MRI (OR=3.519, P<0.05). Conclusions: There was a high incidence of brain abnormalities in NMO. Subependymal white matter, corpus callosum, hypothalamus and brain stem were often involved in NMO. NMO patients with coexisting autoimmune disease and infection history had higher risk of brain abnormalities. (authors)

Seizure-induced brain lesions: A wide spectrum of variably reversible MRI abnormalities

International Nuclear Information System (INIS)

Cianfoni, A.; Caulo, M.; Cerase, A.; Della Marca, G.; Falcone, C.; Di Lella, G.M.; Gaudino, S.; Edwards, J.; Colosimo, C.

2013-01-01

Introduction MRI abnormalities in the postictal period might represent the effect of the seizure activity, rather than its structural cause. Material and Methods Retrospective review of clinical and neuroimaging charts of 26 patients diagnosed with seizure-related MR-signal changes. All patients underwent brain-MRI (1.5-Tesla, standard pre- and post-contrast brain imaging, including DWI-ADC in 19/26) within 7 days from a seizure and at least one follow-up MRI, showing partial or complete reversibility of the MR-signal changes. Extensive clinical work-up and follow-up, ranging from 3 months to 5 years, ruled out infection or other possible causes of brain damage. Seizure-induced brain-MRI abnormalities remained a diagnosis of exclusion. Site, characteristics and reversibility of MRI changes, and association with characteristics of seizures were determined. Results MRI showed unilateral (13/26) and bilateral abnormalities, with high (24/26) and low (2/26) T2-signal, leptomeningeal contrast-enhancement (2/26), restricted diffusion (9/19). Location of abnormality was cortical/subcortical, basal ganglia, white matter, corpus callosum, cerebellum. Hippocampus was involved in 10/26 patients. Reversibility of MRI changes was complete in 15, and with residual gliosis or focal atrophy in 11 patients. Reversibility was noted between 15 and 150 days (average, 62 days). Partial simple and complex seizures were associated with hippocampal involvement (p = 0.015), status epilepticus with incomplete reversibility of MRI abnormalities (p = 0.041). Conclusions Seizure or epileptic status can induce transient, variably reversible MRI brain abnormalities. Partial seizures are frequently associated with hippocampal involvement and status epilepticus with incompletely reversible lesions. These seizure-induced MRI abnormalities pose a broad differential diagnosis; increased awareness may reduce the risk of misdiagnosis and unnecessary intervention

Seizure-induced brain lesions: A wide spectrum of variably reversible MRI abnormalities

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Cianfoni, A., E-mail: acianfoni@hotmail.com [Neuroradiology, Neurocenter of Italian Switzerland–Ospedale regionale Lugano, Via Tesserete 46, Lugano, 6900, CH (Switzerland); Caulo, M., E-mail: caulo@unich.it [Department of Neuroscience and Imaging, University of Chieti, Via dei Vestini 33, 6610 Chieti. Italy (Italy); Cerase, A., E-mail: alfonsocerase@gmail.com [Unit of Neuroimaging and Neurointervention NINT, Department of Neurological and Sensorineural Sciences, Azienda Ospedaliera Universitaria Senese, Policlinico “Santa Maria alle Scotte”, V.le Bracci 16, Siena (Italy); Della Marca, G., E-mail: dellamarca@rm.unicatt.it [Neurology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy); Falcone, C., E-mail: carlo_falc@libero.it [Radiology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy); Di Lella, G.M., E-mail: gdilella@rm.unicatt.it [Radiology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy); Gaudino, S., E-mail: sgaudino@sirm.org [Radiology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy); Edwards, J., E-mail: edwardjc@musc.edu [Neuroscience Dept., Medical University of South Carolina, 96J Lucas st, 29425, Charleston, SC (United States); Colosimo, C., E-mail: colosimo@rm.unicatt.it [Radiology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy)

2013-11-01

Introduction MRI abnormalities in the postictal period might represent the effect of the seizure activity, rather than its structural cause. Material and Methods Retrospective review of clinical and neuroimaging charts of 26 patients diagnosed with seizure-related MR-signal changes. All patients underwent brain-MRI (1.5-Tesla, standard pre- and post-contrast brain imaging, including DWI-ADC in 19/26) within 7 days from a seizure and at least one follow-up MRI, showing partial or complete reversibility of the MR-signal changes. Extensive clinical work-up and follow-up, ranging from 3 months to 5 years, ruled out infection or other possible causes of brain damage. Seizure-induced brain-MRI abnormalities remained a diagnosis of exclusion. Site, characteristics and reversibility of MRI changes, and association with characteristics of seizures were determined. Results MRI showed unilateral (13/26) and bilateral abnormalities, with high (24/26) and low (2/26) T2-signal, leptomeningeal contrast-enhancement (2/26), restricted diffusion (9/19). Location of abnormality was cortical/subcortical, basal ganglia, white matter, corpus callosum, cerebellum. Hippocampus was involved in 10/26 patients. Reversibility of MRI changes was complete in 15, and with residual gliosis or focal atrophy in 11 patients. Reversibility was noted between 15 and 150 days (average, 62 days). Partial simple and complex seizures were associated with hippocampal involvement (p = 0.015), status epilepticus with incomplete reversibility of MRI abnormalities (p = 0.041). Conclusions Seizure or epileptic status can induce transient, variably reversible MRI brain abnormalities. Partial seizures are frequently associated with hippocampal involvement and status epilepticus with incompletely reversible lesions. These seizure-induced MRI abnormalities pose a broad differential diagnosis; increased awareness may reduce the risk of misdiagnosis and unnecessary intervention.

Possibilities opened up by MRI in the diagnosis of hand and wrist abnormalities

International Nuclear Information System (INIS)

Heuck, A.; Steinbach, L.; Stoller, D.; Genant, H.

1989-01-01

MRI studies of 63 patients with various abnormalities of the hand and wrist were analyzed. Studies were performed on scanners with a field strength of 0.35, 0.5, or 1.5 T. Imaging parameters included T1- and T2-weighted sequences in the coronal and transverse planes and contiguous slices 3-5 mm thick. In 37 patients with post-traumatic disorders, MRI revealed carpal avascular necrosis, tendon abnormalities and, in some cases, abnormalities of interosseous ligaments and the triangular fibrocartilage. In 15 patients with such inflammatory diseases as arthritis, tenosynovitis and carpal tunnel syndrome and in 11 patients with tumors, MRI provided clear delineation of osseous and soft tissue abnormalities. The current role of MRI in the diagnosis of hand and wrist abnormalities is discussed on the basis of these results. (orig.) [de

Possibilities opened up by MRI in the diagnosis of hand and wrist abnormalities

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Heuck, A; Steinbach, L; Stoller, D; Genant, H; Neumann, C

1989-02-01

MRI studies of 63 patients with various abnormalities of the hand and wrist were analyzed. Studies were performed on scanners with a field strength of 0.35, 0.5, or 1.5 T. Imaging parameters included T1- and T2-weighted sequences in the coronal and transverse planes and contiguous slices 3-5 mm thick. In 37 patients with post-traumatic disorders, MRI revealed carpal avascular necrosis, tendon abnormalities and, in some cases, abnormalities of interosseous ligaments and the triangular fibrocartilage. In 15 patients with such inflammatory diseases as arthritis, tenosynovitis and carpal tunnel syndrome and in 11 patients with tumors, MRI provided clear delineation of osseous and soft tissue abnormalities. The current role of MRI in the diagnosis of hand and wrist abnormalities is discussed on the basis of these results.

High-resolution 3 T MRI of traumatic and degenerative triangular fibrocartilage complex (TFCC) abnormalities using Palmer and Outerbridge classifications.

Science.gov (United States)

Nozaki, T; Rafijah, G; Yang, L; Ueno, T; Horiuchi, S; Hitt, D; Yoshioka, H

2017-10-01

To investigate the usefulness of high-resolution 3 T magnetic resonance imaging (MRI) for the evaluation of traumatic and degenerative triangular fibrocartilage complex (TFCC) abnormalities among three groups: patients presenting with wrist pain who were (a) younger than age 50 years or (b) age 50 or older (PT<50 and PT≥50, respectively), and (c) asymptomatic controls who were younger than age 50 years (AC). High-resolution 3 T MRI was evaluated retrospectively in 96 patients, including 47 PT<50, 38 PT≥50, and 11 AC. Two board-certified radiologists reviewed the MRI images independently. MRI features of TFCC injury were analysed according to the Palmer classification, and cartilage degeneration around the TFCC was evaluated using the Outerbridge classification. Differences in MRI findings among these groups were detected using chi-square test. Cohen's kappa was calculated to assess interobserver and intra-observer reliability. The incidence of Palmer class 1A, 1C and 1D traumatic TFCC injury was significantly (p<0.05) higher in PT≥50 than in PT<50 (class 1A: 47.4% versus 27.7%, class 1C: 31.6% versus 12.8%, and class 1D: 21.1% versus 2.1%). Likewise, MRI findings of TFCC degeneration were observed more frequently in PT≥50 than in PT<50 (p<0.01). Outerbridge grade 2 or higher cartilage degeneration was significantly (p<0.01) more frequently seen in PT≥50 than in PT<50 (55.3% versus 17% in the lunate, 28.9% versus 4.3% in the triquetrum, 73.7% versus 12.8% in the ulna). High-resolution wrist MRI at 3 T enables detailed evaluation of TFCC traumatic injury and degenerative changes using the Palmer and Outerbridge classifications, with good or excellent interobserver and intra-observer reliability. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

MRI Volume Fusion Based on 3D Shearlet Decompositions.

Science.gov (United States)

Duan, Chang; Wang, Shuai; Wang, Xue Gang; Huang, Qi Hong

2014-01-01

Nowadays many MRI scans can give 3D volume data with different contrasts, but the observers may want to view various contrasts in the same 3D volume. The conventional 2D medical fusion methods can only fuse the 3D volume data layer by layer, which may lead to the loss of interframe correlative information. In this paper, a novel 3D medical volume fusion method based on 3D band limited shearlet transform (3D BLST) is proposed. And this method is evaluated upon MRI T2* and quantitative susceptibility mapping data of 4 human brains. Both the perspective impression and the quality indices indicate that the proposed method has a better performance than conventional 2D wavelet, DT CWT, and 3D wavelet, DT CWT based fusion methods.

MRI Volume Fusion Based on 3D Shearlet Decompositions

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Chang Duan

2014-01-01

Full Text Available Nowadays many MRI scans can give 3D volume data with different contrasts, but the observers may want to view various contrasts in the same 3D volume. The conventional 2D medical fusion methods can only fuse the 3D volume data layer by layer, which may lead to the loss of interframe correlative information. In this paper, a novel 3D medical volume fusion method based on 3D band limited shearlet transform (3D BLST is proposed. And this method is evaluated upon MRI T2* and quantitative susceptibility mapping data of 4 human brains. Both the perspective impression and the quality indices indicate that the proposed method has a better performance than conventional 2D wavelet, DT CWT, and 3D wavelet, DT CWT based fusion methods.

Dielectric properties of 3D-printed materials for anatomy specific 3D-printed MRI coils

Science.gov (United States)

Behzadnezhad, Bahareh; Collick, Bruce D.; Behdad, Nader; McMillan, Alan B.

2018-04-01

Additive manufacturing provides a low-cost and rapid means to translate 3D designs into the construction of a prototype. For MRI, this type of manufacturing can be used to construct various components including the structure of RF coils. In this paper, we characterize the material properties (dielectric constant and loss tangent) of several common 3D-printed polymers in the MRI frequency range of 63-300 MHz (for MRI magnetic field strengths of 1.5-7 T), and utilize these material properties in full-wave electromagnetic simulations to design and construct a very low-cost subject/anatomy-specific 3D-printed receive-only RF coil that fits close to the body. We show that the anatomy-specific coil exhibits higher signal-to-noise ratio compared to a conventional flat surface coil.

Cognition and brain abnormalities on MRI in pituitary patients

International Nuclear Information System (INIS)

Brummelman, Pauline; Sattler, Margriet G.A.; Meiners, Linda C.; Berg, Gerrit van den; Klauw, Melanie M. van der; Elderson, Martin F.; Dullaart, Robin P.F.; Koerts, Janneke; Werumeus Buning, Jorien; Tucha, Oliver; Wolffenbuttel, Bruce H.R.; Bergh, Alfons C.M. van den; Beek, André P. van

2015-01-01

Highlights: • Cognitive impairments are frequently observed in treated NFA patients. • NFA patients with cognitive impairments do not show brain abnormalities on MRI more frequently than patients without cognitive impairments. • The absence of brain abnormalities on brain MRI does not exclude impairments of cognition. - Abstract: Purpose: The extent to which cognitive dysfunction is related to specific brain abnormalities in patients treated for pituitary macroadenoma is unclear. Therefore, we compared brain abnormalities seen on Magnetic Resonance Imaging (MRI) in patients treated for nonfunctioning pituitary macroadenoma (NFA) with or without impairments in cognitive functioning. Methods: In this cross-sectional design, a cohort of 43 NFA patients was studied at the University Medical Center Groningen. White matter lesions (WMLs), cerebral atrophy, (silent) brain infarcts and abnormalities of the temporal lobes and hippocampi were assessed on pre-treatment and post-treatment MRI scans. Post-treatment cognitive examinations were performed using a verbal memory and executive functioning test. We compared our patient cohort with large reference populations representative of the Dutch population. Results: One or more impairments on both cognitive tests were frequently observed in treated NFA patients. No treatment effects were found with regard to the comparison between patients with and without impairments in executive functioning. Interestingly, in patients with one or more impairments on verbal memory function, treatment with radiotherapy had been given more frequently (74% in the impaired group versus 40% in the unimpaired group, P = 0.025). Patients with or without any brain abnormality on MRI did not differ in verbal memory or executive functioning. Conclusions: Brain abnormalities on MRI are not observed more frequently in treated NFA patients with impairments compared to NFA patients without impairments in verbal memory or executive functioning

Cognition and brain abnormalities on MRI in pituitary patients

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Brummelman, Pauline [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); Sattler, Margriet G.A. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen (Netherlands); Department of Radiation Oncology, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands); Meiners, Linda C. [Department of Radiology, University of Groningen, University Medical Center Groningen (Netherlands); Berg, Gerrit van den; Klauw, Melanie M. van der [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); Elderson, Martin F. [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); LifeLines Cohort Study and Biobank, University of Groningen, University Medical Center Groningen (Netherlands); Dullaart, Robin P.F. [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); Koerts, Janneke [Department of Clinical and Developmental Neuropsychology, University of Groningen, Groningen (Netherlands); Werumeus Buning, Jorien, E-mail: j.werumeus.buning@umcg.nl [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); Tucha, Oliver [Department of Clinical and Developmental Neuropsychology, University of Groningen, Groningen (Netherlands); Wolffenbuttel, Bruce H.R. [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); LifeLines Cohort Study and Biobank, University of Groningen, University Medical Center Groningen (Netherlands); Bergh, Alfons C.M. van den [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen (Netherlands); Beek, André P. van, E-mail: a.p.van.beek@umcg.nl [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands)

2015-02-15

Highlights: • Cognitive impairments are frequently observed in treated NFA patients. • NFA patients with cognitive impairments do not show brain abnormalities on MRI more frequently than patients without cognitive impairments. • The absence of brain abnormalities on brain MRI does not exclude impairments of cognition. - Abstract: Purpose: The extent to which cognitive dysfunction is related to specific brain abnormalities in patients treated for pituitary macroadenoma is unclear. Therefore, we compared brain abnormalities seen on Magnetic Resonance Imaging (MRI) in patients treated for nonfunctioning pituitary macroadenoma (NFA) with or without impairments in cognitive functioning. Methods: In this cross-sectional design, a cohort of 43 NFA patients was studied at the University Medical Center Groningen. White matter lesions (WMLs), cerebral atrophy, (silent) brain infarcts and abnormalities of the temporal lobes and hippocampi were assessed on pre-treatment and post-treatment MRI scans. Post-treatment cognitive examinations were performed using a verbal memory and executive functioning test. We compared our patient cohort with large reference populations representative of the Dutch population. Results: One or more impairments on both cognitive tests were frequently observed in treated NFA patients. No treatment effects were found with regard to the comparison between patients with and without impairments in executive functioning. Interestingly, in patients with one or more impairments on verbal memory function, treatment with radiotherapy had been given more frequently (74% in the impaired group versus 40% in the unimpaired group, P = 0.025). Patients with or without any brain abnormality on MRI did not differ in verbal memory or executive functioning. Conclusions: Brain abnormalities on MRI are not observed more frequently in treated NFA patients with impairments compared to NFA patients without impairments in verbal memory or executive functioning

"Black Bone" MRI: a novel imaging technique for 3D printing.

Science.gov (United States)

Eley, Karen A; Watt-Smith, Stephen R; Golding, Stephen J

2017-03-01

Three-dimensionally printed anatomical models are rapidly becoming an integral part of pre-operative planning of complex surgical cases. We have previously reported the "Black Bone" MRI technique as a non-ionizing alternative to CT. Segmentation of bone becomes possible by minimizing soft tissue contrast to enhance the bone-soft tissue boundary. The objectives of this study were to ascertain the potential of utilizing this technique to produce three-dimensional (3D) printed models. "Black Bone" MRI acquired from adult volunteers and infants with craniosynostosis were 3D rendered and 3D printed. A custom phantom provided a surrogate marker of accuracy permitting comparison between direct measurements and 3D printed models created by segmenting both CT and "Black Bone" MRI data sets using two different software packages. "Black Bone" MRI was successfully utilized to produce 3D models of the craniofacial skeleton in both adults and an infant. Measurements of the cube phantom and 3D printed models demonstrated submillimetre discrepancy. In this novel preliminary study exploring the potential of 3D printing from "Black Bone" MRI data, the feasibility of producing anatomical 3D models has been demonstrated, thus offering a potential non-ionizing alterative to CT for the craniofacial skeleton.

Clinical feasibility and validation of 3D principal strain analysis from cine MRI: comparison to 2D strain by MRI and 3D speckle tracking echocardiography.

Science.gov (United States)

Satriano, Alessandro; Heydari, Bobak; Narous, Mariam; Exner, Derek V; Mikami, Yoko; Attwood, Monica M; Tyberg, John V; Lydell, Carmen P; Howarth, Andrew G; Fine, Nowell M; White, James A

2017-12-01

Two-dimensional (2D) strain analysis is constrained by geometry-dependent reference directions of deformation (i.e. radial, circumferential, and longitudinal) following the assumption of cylindrical chamber architecture. Three-dimensional (3D) principal strain analysis may overcome such limitations by referencing intrinsic (i.e. principal) directions of deformation. This study aimed to demonstrate clinical feasibility of 3D principal strain analysis from routine 2D cine MRI with validation to strain from 2D tagged cine analysis and 3D speckle tracking echocardiography. Thirty-one patients undergoing cardiac MRI were studied. 3D strain was measured from routine, multi-planar 2D cine SSFP images using custom software designed to apply 4D deformation fields to 3D cardiac models to derive principal strain. Comparisons of strain estimates versus those by 2D tagged cine, 2D non-tagged cine (feature tracking), and 3D speckle tracking echocardiography (STE) were performed. Mean age was 51 ± 14 (36% female). Mean LV ejection fraction was 66 ± 10% (range 37-80%). 3D principal strain analysis was feasible in all subjects and showed high inter- and intra-observer reproducibility (ICC range 0.83-0.97 and 0.83-0.98, respectively-p analysis is feasible using routine, multi-planar 2D cine MRI and shows high reproducibility with strong correlations to 2D conventional strain analysis and 3D STE-based analysis. Given its independence from geometry-related directions of deformation this technique may offer unique benefit for the detection and prognostication of myocardial disease, and warrants expanded investigation.

Influence of MRI abnormality in skull base bone on prognosis of nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Jin-Cheng, Lu; Qing, Wei; Yi-Qin, Zhang; Feng, Li

2004-01-01

Purpose. To evaluate the influence of skull base bone (SBB) abnormality showed by MRI on prognosis of nasopharyngeal carcinoma (NPC). Patients and methods. From March 1993 to December 1998, 122 NPC patients received prime radiotherapy treatment. All of them were proved pathologically and checked by magnetic resonance imaging (MRI). Every patient received radiation through conjoint facio-cervical field and conventional dose-fractionation schedules. The total dose to the primary tumor was 60 5 Gy (median, 70 Gy). The Kaplan Meier method, the Log-rank test and the Cox regression model were used to evaluate the significance of prognostic factors on NPC patient survival. Results. The overall median survival period was 50 (6 2) months, and the 1, 3 and 5 year-survival rates were, respectively, 99.2%, 87.9%, and 73.3%. The 1, 3, and 5 year-survival rates of abnormality and normality of the SBB on MRI were 98.9%, 87.2%, 71.9%, and 100.0%, 89.8%, 77.0%, respectively (P 0.4233). Gender, age, head pain, SBB abnormality, cranial nerve palsy, cervical lymphadenopathy and primary tumor extent were analyzed with the Cox regression model and SBB abnormality on MRI did not prove to have statistical significance (P = 0.6934). According to the analysis of regrouping, patients with SBB abnormalities ≥ sites have a worse prognosis (P = 0.0427). Then. the above seven factors are analyzed by Cox regression model and the result had statistical significance (P = 0.0385). Conclusion. The SBB abnormality on MRI is of no obvious influence on prognosis of NPC. However, when SBB abnormality sites were ≥ 2, there is obvious statistical significance on the prognosis. (author)

Contrast-enhanced 3D MRI of lung perfusion in children with cystic fibrosis - initial results

International Nuclear Information System (INIS)

Eichinger, Monika; Puderbach, Michael; Zuna, Ivan; Kauczor, Hans-Ulrich; Fink, Christian; Gahr, Julie; Mueller, Frank-Michael; Ley, Sebastian; Plathow, Christian; Tuengerthal, Siegfried

2006-01-01

This paper is a feasibility study of magnetic resonance imaging (MRI) of lung perfusion in children with cystic fibrosis (CF) using contrast-enhanced 3D MRI. Correlation assessment of perfusion changes with structural abnormalities. Eleven CF patients (9 f, 2 m; median age 16 years) were examined at 1.5 T. Morphology: HASTE coronal, transversal (TR/TE/α/ST: 600 ms/28 ms/180 /6 mm), breath-hold 18 s. Perfusion: Time-resolved 3D GRE pulse sequence (FLASH, TE/TR/α: 0.8/1.9 ms/40 ), parallel imaging (GRAPPA, PAT 2). Twenty-five data sets were acquired after intravenous injection of 0.1 mmol/kg body weight of gadodiamide, 3-5 ml/s. A total of 198 lung segments were analyzed by two radiologists in consensus and scored for morphological and perfusion changes. Statistical analysis was performed by Mantel-Haenszel chi-square test. Results showed that perfusion defects were observed in all patients and present in 80% of upper, and 39% of lower lobes. Normal lung parenchyma showed homogeneous perfusion (86%, P<0.0001). Severe morphological changes led to perfusion defects (97%, P<0.0001). Segments with moderate morphological changes showed normal (53%) or impaired perfusion (47%). In conclusion, pulmonary perfusion is easy to judge in segments with normal parenchyma or severe changes. In moderately damaged segments, MRI of lung perfusion may help to better assess actual functional impairment. Contrast-enhanced 3D MRI of lung perfusion has the potential for early vascular functional assessment and therapy control in CF patients. (orig.)

3D-Flair sequence at 3T in cochlear otosclerosis

International Nuclear Information System (INIS)

Lombardo, Francesco; De Cori, Sara; Aghakhanyan, Gayane; Montanaro, Domenico; De Marchi, Daniele; Frijia, Francesca; Canapicchi, Raffaello; Fortunato, Susanna; Forli, Francesca; Berrettini, Stefano; Chiappino, Dante

2016-01-01

To assess the capability of three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) sequences in detecting signal alterations of the endolabyrinthine fluid in patients with otosclerosis. 3D-FLAIR before and after (-/+) gadolinium (Gd) administration was added to the standard MR protocol and acquired in 13 patients with a clinical/audiological diagnosis of severe/profound hearing loss in otosclerosis who were candidates for cochlear implantation and in 11 control subjects using 3-T magnetic resonance imaging (MRI) equipment. The MRI signal of the fluid-filled cochlea was assessed both visually and calculating the signal intensity ratio (SIR = signal intensity cochlea/brainstem). We revealed no endocochlear signal abnormalities on T1-weighted -/+ Gd images for either group, while on 3D-FLAIR we found bilateral hyperintensity with enhancement after Gd administration in eight patients and bilateral hyperintensity without enhancement in one patient. No endocochlear signal abnormalities were detected in other patients or the control group. Using 3-T MRI equipment, the 3D-FLAIR -/+ Gd sequence is able to detect the blood-labyrinth barrier (BLB) breakdown responsible for alterations of the endolabyrinthine fluid in patients with cochlear otosclerosis. We believe that 3D-FLAIR +/- Gd is an excellent imaging modality to assess the intra-cochlear damage in otosclerosis patients. (orig.)

3D-Flair sequence at 3T in cochlear otosclerosis

Energy Technology Data Exchange (ETDEWEB)

Lombardo, Francesco; De Cori, Sara; Aghakhanyan, Gayane; Montanaro, Domenico; De Marchi, Daniele; Frijia, Francesca; Canapicchi, Raffaello [Fondazione CNR Regione Toscana ' ' G. Monasterio' ' , Neuroradiology Unit, Pisa (Italy); Fortunato, Susanna; Forli, Francesca; Berrettini, Stefano [University of Pisa, ENT Audiology Phoniatry Unit, Department of Neuroscience, Pisa (Italy); Chiappino, Dante [Fondazione CNR Regione Toscana ' ' G. Monasterio' ' , Department of Radiology, Massa (Italy)

2016-10-15

To assess the capability of three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) sequences in detecting signal alterations of the endolabyrinthine fluid in patients with otosclerosis. 3D-FLAIR before and after (-/+) gadolinium (Gd) administration was added to the standard MR protocol and acquired in 13 patients with a clinical/audiological diagnosis of severe/profound hearing loss in otosclerosis who were candidates for cochlear implantation and in 11 control subjects using 3-T magnetic resonance imaging (MRI) equipment. The MRI signal of the fluid-filled cochlea was assessed both visually and calculating the signal intensity ratio (SIR = signal intensity cochlea/brainstem). We revealed no endocochlear signal abnormalities on T1-weighted -/+ Gd images for either group, while on 3D-FLAIR we found bilateral hyperintensity with enhancement after Gd administration in eight patients and bilateral hyperintensity without enhancement in one patient. No endocochlear signal abnormalities were detected in other patients or the control group. Using 3-T MRI equipment, the 3D-FLAIR -/+ Gd sequence is able to detect the blood-labyrinth barrier (BLB) breakdown responsible for alterations of the endolabyrinthine fluid in patients with cochlear otosclerosis. We believe that 3D-FLAIR +/- Gd is an excellent imaging modality to assess the intra-cochlear damage in otosclerosis patients. (orig.)

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)

Anisotropic Diffusion based Brain MRI Segmentation and 3D Reconstruction

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M. Arfan Jaffar

2012-06-01

Full Text Available In medical field visualization of the organs is very imperative for accurate diagnosis and treatment of any disease. Brain tumor diagnosis and surgery also required impressive 3D visualization of the brain to the radiologist. Detection and 3D reconstruction of brain tumors from MRI is a computationally time consuming and error-prone task. Proposed system detects and presents a 3D visualization model of the brain and tumor inside which greatly helps the radiologist to effectively diagnose and analyze the brain tumor. We proposed a multi-phase segmentation and visualization technique which overcomes the many problems of 3D volume segmentation methods like lake of fine details. In this system segmentation is done in three different phases which reduces the error chances. The system finds contours for skull, brain and tumor. These contours are stacked over and two novel methods are used to find the 3D visualization models. The results of these techniques, particularly of interpolation based, are impressive. Proposed system is tested against publically available data set [41] and MRI datasets available from MRI aamp; CT center Rawalpindi, Pakistan [42].

[Interest using 3D ultrasound and MRI fusion biopsy for prostate cancer detection].

Science.gov (United States)

Marien, A; De Castro Abreu, A; Gill, I; Villers, A; Ukimura, O

2017-09-01

The strategic therapy for prostate cancer depends on histo-pronostics data, which could be upgraded by obtaining targeted biopsies (TB) with MRI (magnetic resonance imagery) fusion 3D ultrasound. To compare diagnostic yield of image fusion guided prostate biopsy using image fusion of multi-parametric MRI (mpMRI) with 3D-TRUS. Between January 2010 and April 2013, 179 consecutive patients underwent outpatient TRUS biopsy using the real-time 3D TRUS tracking system (Urostation™). These patients underwent MRI-TRUS fusion targeted biopsies (TB) with 3D volume data of the MRI elastically fused with 3D TRUS at the time of biopsy. A hundred and seventy-three patients had TBs with fusion. Mean biopsy core per patient were 11.1 (6-14) for SB and 2.4 (1-6) for TB. SBs were positive in 11% compared to 56% for TB (Pperform the higher level of MR/US fusion and should be use for active surveillance. 4. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

In vivo analysis of the human superficial cerebral venous anatomy by using 3D-MRI

International Nuclear Information System (INIS)

Fujinaga, Yasunari

1997-01-01

The purpose of this study is to show the reliability of three dimensional magnetic resonance imaging (3D-MRI), and to classify the drainage patterns of the superficial cerebral veins. At first, toothpicks were stuck into fixed brain surface of a dog. To examine the best methods for making 3D-MRI, the 3D-MRI, including the diameter of the holes, of the dog's brain were analyzed in four threshold values. The holes on the 3D-MRI appeared smaller than their actual size due to the partial volume effect. The low threshold showed more errors than the higher. This result showed it was necessary to display the good 3D-MRI to refer the original MR images. Next, the 3D-MRI of clinical patients who had brain tumors were correlated with operative findings especially in relation to the lesions and brain surface, vessels, ventricles. The relation between the lesions and brain surface, vessels were displayed well, but there were some problems with inadequate ventricular display. Finally, anatomical study using 3D-MRI was performed, because 3D-MRI could display the relation between the brain surface and the superficial cerebral veins in the basic studies. The third study demonstrated that the transverse frontal vein was found in 15%, vein of Trolard ran in front of the central sulcus in 91.5% and several anastomosing veins were frequently observed. These studies showed the progress of technology in bringing about a lot of new information by using 3D-MRI. (author)

Comparison between MRI and 3D-SSP in olivopontocerebellar atrophy and cortical cerebellar atrophy

International Nuclear Information System (INIS)

Hamaguchi, Hirotoshi; Kanda, Fumio; Hosaka, Kayo; Fujii, Masahiko; Chihara, Kazuo

2004-01-01

We compared images of three-dimensional stereotactic surface projections (3D-SSP) of SPECT with MRI images in spinocerebellar degeneration patients (13 olivopontocerebellar atrophy (OPCA) and 7 cortical cerebellar atrophy (CCA)). We analyzed a brain blood flow pattern with an image of statistics by 123 I-IMP SPECT. In OPCA patients, a blood flow reduction was more remarkable in 3D-SSP than a degree of cerebellar atrophy in MRI. In patients with CCA, the cerebellum showed little blood flow reduction in 3D-SSP despite of apparent atrophy in MRI. Simultaneous examination both MRI and 3D-SSP might be useful for differential diagnosis of spinocerebellar degenerations. (author)

Detection and grading of dAVF: prospects and limitations of 3T MRI.

Science.gov (United States)

Bink, Andrea; Berkefeld, Joachim; Wagner, Marlies; You, Se-Jong; Ackermann, Hanns; Lorenz, Matthias W; Senft, Christian; du Mesnil de Rochemont, Richard

2012-02-01

DSA is currently the criterion standard for the assessment of dural arteriovenous fistulas (dAVF). Recently, evolving MRA techniques have emerged as a non-invasive alternative. The aim of this study is to assess the value of 3 T MRI in detecting and describing dAVF and to determine whether MRI can replace DSA as diagnostic procedure. A total of 19 patients with dAVF and 19 without dAVF underwent the same MRI protocol, including 3D time-of-flight MRA and time-resolved contrast-enhanced MRA. The images were evaluated retrospectively by three independent readers with different levels of experience blinded to clinical information. The readers assessed the presence, the site, the venous drainage and the feeders of dAVF. Sensitivity, specificity, accuracy, intertechnique and interobserver agreements were calculated. DAVF can be detected with high sensitivity, specificity and accuracy by experienced and also by less experienced readers. However, MRI has limitations when used for grading and evaluation of the angioarchitecture of the dAVF. Different experience, the limited resolution of MRI and its inability to selectively display arteries were the reasons for these limitations. With MRI dAVF can be detected reliably. Nevertheless, at present MRI can not fully replace DSA, especially for treatment planning.

3D structure tensor analysis of light microscopy data for validating diffusion MRI.

Science.gov (United States)

Khan, Ahmad Raza; Cornea, Anda; Leigland, Lindsey A; Kohama, Steven G; Jespersen, Sune Nørhøj; Kroenke, Christopher D

2015-05-01

Diffusion magnetic resonance imaging (d-MRI) is a powerful non-invasive and non-destructive technique for characterizing brain tissue on the microscopic scale. However, the lack of validation of d-MRI by independent experimental means poses an obstacle to accurate interpretation of data acquired using this method. Recently, structure tensor analysis has been applied to light microscopy images, and this technique holds promise to be a powerful validation strategy for d-MRI. Advantages of this approach include its similarity to d-MRI in terms of averaging the effects of a large number of cellular structures, and its simplicity, which enables it to be implemented in a high-throughput manner. However, a drawback of previous implementations of this technique arises from it being restricted to 2D. As a result, structure tensor analyses have been limited to tissue sectioned in a direction orthogonal to the direction of interest. Here we describe the analytical framework for extending structure tensor analysis to 3D, and utilize the results to analyze serial image "stacks" acquired with confocal microscopy of rhesus macaque hippocampal tissue. Implementation of 3D structure tensor procedures requires removal of sources of anisotropy introduced in tissue preparation and confocal imaging. This is accomplished with image processing steps to mitigate the effects of anisotropic tissue shrinkage, and the effects of anisotropy in the point spread function (PSF). In order to address the latter confound, we describe procedures for measuring the dependence of PSF anisotropy on distance from the microscope objective within tissue. Prior to microscopy, ex vivo d-MRI measurements performed on the hippocampal tissue revealed three regions of tissue with mutually orthogonal directions of least restricted diffusion that correspond to CA1, alveus and inferior longitudinal fasciculus. We demonstrate the ability of 3D structure tensor analysis to identify structure tensor orientations that

MRI or not to MRI! Should brain MRI be a routine investigation in children with autistic spectrum disorders?

Science.gov (United States)

Zeglam, Adel M; Al-Ogab, Marwa F; Al-Shaftery, Thouraya

2015-09-01

To evaluate the routine usage of Magnetic Resonance Imaging (MRI) of brain and estimate the prevalence of brain abnormalities in children presenting to the Neurodevelopment Clinic of Al-Khadra Hospital (NDC-KH), Tripoli, Libya with autistic spectrum disorders (ASD). The records of all children with ASD presented to NDC-KH over 4-year period (from January 2009 to December 2012) were reviewed. All MRIs were acquired with a 1.5-T Philips (3-D T1, T2, FLAIR coronal and axial sequences). MRIs were reported to be normal, abnormal or no significant abnormalities by a consultant neuroradiologist. One thousand and seventy-five children were included in the study. Seven hundred and eighty-two children (72.7 %) had an MRI brain of whom 555 (71 %) were boys. 26 children (24 males and 2 females) (3.3 %) demonstrated MRI abnormalities (8 leukodystrophic changes, 4 periventricular leukomalacia, 3 brain atrophy, 2 tuberous sclerosis, 2 vascular changes, 1 pineoblastoma, 1 cerebellar angioma, 1 cerebellar hypoplasia, 3 agenesis of corpus callosum, 1 neuro-epithelial cyst). An unexpectedly high rate of MRI abnormalities was found in the first large series of clinical MRI investigations in children with autism. These results could contribute to further research into the pathogenesis of autistic spectrum disorder.

[3D-visualization by MRI for surgical planning of Wilms tumors].

Science.gov (United States)

Schenk, J P; Waag, K-L; Graf, N; Wunsch, R; Jourdan, C; Behnisch, W; Tröger, J; Günther, P

2004-10-01

To improve surgical planning of kidney tumors in childhood (Wilms tumor, mesoblastic nephroma) after radiologic verification of the presumptive diagnosis with interactive colored 3D-animation in MRI. In 7 children (1 boy, 6 girls) with a mean age of 3 years (1 month to 11 years), the MRI database (DICOM) was processed with a raycasting-based 3D-volume-rendering software (VG Studio Max 1.1/Volume Graphics). The abdominal MRI-sequences (coronal STIR, coronal T1 TSE, transverse T1/T2 TSE, sagittal T2 TSE, transverse and coronal T1 TSE post contrast) were obtained with a 0.5T unit in 4 - 6 mm slices. Additionally, a phase-contrast-MR-angiography was applied to delineate the large abdominal and retroperitoneal vessels. A notebook was used to demonstrate the 3D-visualization for surgical planning before surgery and during the surgical procedure. In all 7 cases, the surgical approach was influenced by interactive 3D-animation and the information found useful for surgical planning. Above all, the 3D-visualization demonstrates the mass effect of the Wilms tumor and its anatomical relationship to the renal hilum and to the rest of the kidney as well as the topographic relationship of the tumor to the critical vessels. One rupture of the tumor capsule occurred as a surgical complication. For the surgeon, the transformation of the anatomical situation from MRI to the surgical situs has become much easier. For surgical planning of Wilms tumors, the 3D-visualization with 3D-animation of the situs helps to transfer important information from the pediatric radiologist to the pediatric surgeon and optimizes the surgical preparation. A reduction of complications is to be expected.

3D-visualization by MRI for surgical planning of Wilms tumors

International Nuclear Information System (INIS)

Schenk, J.P.; Wunsch, R.; Jourdan, C.; Troeger, J.; Waag, K.-L.; Guenther, P.; Graf, N.; Behnisch, W.

2004-01-01

Purpose: To improve surgical planning of kidney tumors in childhood (Wilms tumor, mesoblastic nephroma) after radiologic verification of the presumptive diagnosis with interactive colored 3D-animation in MRI. Materials and Methods: In 7 children (1 boy, 6 girls) with a mean age of 3 years (1 month to 11 years), the MRI database (DICOM) was processed with a raycasting-based 3D-volume-rendering software (VG Studio Max 1.1/Volume Graphics). The abdominal MRI-sequences (coronal STIR, coronal T1 TSE, transverse T1/T2 TSE, sagittal T2 TSE, transverse and coronal T1 TSE post contrast) were obtained with a 0.5T unit in 4-6 mm slices. Additionally, phase-contrast-MR-angiography was applied to delineate the large abdominal and retroperitoneal vessels. A notebook was used to demonstrate the 3D-visualization for surgical planning before surgery and during the surgical procedure. Results: In all 7 cases, the surgical approach was influenced by interactive 3D-animation and the information found useful for surgical planning. Above all, the 3D-visualization demonstrates the mass effect of the Wilms tumor and its anatomical relationship to the renal hilum and to the rest of the kidney as well as the topographic relationship of the tumor to the critical vessels. One rupture of the tumor capsule occurred as a surgical complication. For the surgeon, the transformation of the anatomical situation from MRI to the surgical situs has become much easier. Conclusion: For surgical planning of Wilms tumors, the 3D-visualization with 3D-animation of the situs helps to transfer important information from the pediatric radiologist to the pediatric surgeon and optimizes the surgical preparation. A reduction of complications is to be expected. (orig.)

Comparison of 3D and 2D FSE T2-weighted MRI in the diagnosis of deep pelvic endometriosis: Preliminary results

International Nuclear Information System (INIS)

Bazot, M.; Stivalet, A.; Daraï, E.; Coudray, C.; Thomassin-Naggara, I.; Poncelet, E.

2013-01-01

Aim: To evaluate image quality and diagnostic accuracy of two- (2D) and three-dimensional (3D) T2-weighted magnetic resonance imaging (MRI) for the evaluation of deep infiltrating endometriosis (DIE). Materials and methods: One hundred and ten consecutive patients with suspicion of endometriosis were recruited at two institutions over a 5-month period. Twenty-three women underwent surgery, 18 had DIE at histology. Two readers independently evaluated 3D and 2D MRI for image quality and diagnosis of DIE. Descriptive analysis, chi-square test for categorical or nominal variables, McNemar test for comparison between 3D and 2D T2-weighted MRI, and weighted “statistics” for intra- and interobserver agreement were used for statistical analysis. Results: Both readers found that 3D yielded significantly lower image quality than 2D MRI (p < 0.0001). Acquisition time for 3D was significantly shorter than 2D MRI (p < 0.01). 3D offered similar accuracy to diagnose DIE compared to 2D MRI. For all locations of endometriosis, a high or variable intra-observer agreement was observed for reader 1 and 2, respectively. Conclusions: Despite a lower overall image quality, 3D provides significant time saving and similar accuracy than multiplanar 2D MRI in the diagnosis of specific DIE locations.

Simulated radiographic bone and joint modeling from 3D ankle MRI: feasibility and comparison with radiographs and 2D MRI

Energy Technology Data Exchange (ETDEWEB)

Nordeck, Shaun M. [University of Texas Southwestern Medical College, Dallas, TX (United States); University of Texas Southwestern Medical Center, Musculoskeletal Radiology, Dallas, TX (United States); Koerper, Conrad E.; Adler, Aaron [University of Texas Southwestern Medical College, Dallas, TX (United States); Malhotra, Vidur; Xi, Yin [University of Texas Southwestern Medical Center, Musculoskeletal Radiology, Dallas, TX (United States); Liu, George T. [University of Texas Southwestern Medical Center, Orthopaedic Surgery, Dallas, TX (United States); Chhabra, Avneesh [University of Texas Southwestern Medical Center, Musculoskeletal Radiology, Dallas, TX (United States); University of Texas Southwestern Medical Center, Orthopaedic Surgery, Dallas, TX (United States)

2017-05-15

The purpose of this work is to simulate radiographs from isotropic 3D MRI data, compare relationship of angle and joint space measurements on simulated radiographs with corresponding 2D MRIs and real radiographs (XR), and compare measurement times among the three modalities. Twenty-four consecutive ankles were included, eight males and 16 females, with a mean age of 46 years. Segmented joint models simulating radiographs were created from 3D MRI data sets. Three readers independently performed blinded angle and joint space measurements on the models, corresponding 2D MRIs, and XRs at two time points. Linear mixed models and the intraclass correlation coefficient (ICC) was ascertained, with p values less than 0.05 considered significant. Simulated radiograph models were successfully created in all cases. Good agreement (ICC > 0.65) was noted among all readers across all modalities and among most measurements. Absolute measurement values differed between modalities. Measurement time was significantly greater (p < 0.05) on 2D versus simulated radiographs for most measurements and on XR versus simulated radiographs (p < 0.05) for nearly half the measurements. Simulated radiographs can be successfully generated from 3D MRI data; however, measurements differ. Good inter-reader and moderate-to-good intra-reader reliability was observed and measurements obtained on simulated radiograph models took significantly less time compared to measurements with 2D and generally less time than XR. (orig.)

Development and assessment of a new 3D neuroanatomy teaching tool for MRI training.

Science.gov (United States)

Drapkin, Zachary A; Lindgren, Kristen A; Lopez, Michael J; Stabio, Maureen E

2015-01-01

A computerized three-dimensional (3D) neuroanatomy teaching tool was developed for training medical students to identify subcortical structures on a magnetic resonance imaging (MRI) series of the human brain. This program allows the user to transition rapidly between two-dimensional (2D) MRI slices, 3D object composites, and a combined model in which 3D objects are overlaid onto the 2D MRI slices, all while rotating the brain in any direction and advancing through coronal, sagittal, or axial planes. The efficacy of this tool was assessed by comparing scores from an MRI identification quiz and survey in two groups of first-year medical students. The first group was taught using this new 3D teaching tool, and the second group was taught the same content for the same amount of time but with traditional methods, including 2D images of brain MRI slices and 3D models from widely used textbooks and online sources. Students from the experimental group performed marginally better than the control group on overall test score (P = 0.07) and significantly better on test scores extracted from questions involving C-shaped internal brain structures (P teaching tool is an effective way to train medical students to read an MRI of the brain and is particularly effective for teaching C-shaped internal brain structures. © 2015 American Association of Anatomists.

Preliminary experience with fetal MRI for evaluation of intracranial abnormalities

International Nuclear Information System (INIS)

Penev, L.; Georgieva-Kosarova, G.

2015-01-01

Full text: Modern MRI technologies allow the preparation of a multi-planar images as well as images showing the movement of the fetus for less than 1 sec. the methodology is particularly useful as a rendering intracranial lesions (at ventriculomegaly, lesions in the posterior cranial fossa, corpus callosum abnormalities, myelination, migration and sulcation) and in the body lesions of the fetus (diaphragmatic hernia, congenital cystic abnormalities, renal cystic lesions spinal anomalies) and the abdomen of the mother. We set a goal to prove the usefulness of MRI research in prenatal diagnosis of congenital malformations of the central nervous system. For a period of 24 months in City Clinic Hospital Sofia were studied 12 pregnant women and 13 fetuses in which there was doubt about intracranial fetal malformations. All studies were conducted as a supplementary diagnostic technique after ultrasound in the third trimester of pregnancy when the fetus is large enough and organogenesis is completed. MRI is held superconductive 3.0t magnet using single-shot fast-spin echo and half-Fourier acquisition turbo spin echo (HASTE) with a duration of under one minute scan, MRI study therefore does not require preparation of the mother. Does not require use of contrast. None reported harm to the fetus and the mother. Although ultrasound due to its low price and its wide accessibility as well as of its non-invasiveness and low time in some cases results were insufficient to determine condition and course of pregnancy. We believe that the MRI examination in the case of ambiguous results of the ultrasound has an important role to refine abnormalities prenatal and postnatal treatment planning

Regularization of DT-MRI Using 3D Median Filtering Methods

Directory of Open Access Journals (Sweden)

Soondong Kwon

2014-01-01

Full Text Available DT-MRI (diffusion tensor magnetic resonance imaging tractography is a method to determine the architecture of axonal fibers in the central nervous system by computing the direction of the principal eigenvectors obtained from tensor matrix, which is different from the conventional isotropic MRI. Tractography based on DT-MRI is known to need many computations and is highly sensitive to noise. Hence, adequate regularization methods, such as image processing techniques, are in demand. Among many regularization methods we are interested in the median filtering method. In this paper, we extended two-dimensional median filters already developed to three-dimensional median filters. We compared four median filtering methods which are two-dimensional simple median method (SM2D, two-dimensional successive Fermat method (SF2D, three-dimensional simple median method (SM3D, and three-dimensional successive Fermat method (SF3D. Three kinds of synthetic data with different altitude angles from axial slices and one kind of human data from MR scanner are considered for numerical implementation by the four filtering methods.

3D-FT MRI of the facial nerve

International Nuclear Information System (INIS)

Girard, N.; Raybaud, C.; Poncet, M.

1994-01-01

Contrast-enhanced 3D-FT MRI of the intrapetrous facial nerve was obtained in 38 patients with facial nerve disease, using a 1.0 T magnet and fast gradient-echo acquisition sequences. Contiguous millimetric sections were obtained, which could be reformatted in any desired plane. Acutely ill patients, were examined within the first 2 months, included: 24 with Bell's palsy and 6 with other acute disorders (Herpes zoster, trauma, neuroma, meningeal metastasis, middle ear granuloma). Six patients investigated more than a year after the onset of symptoms included 3 with congenital cholesteatoma, 2 with neuromas and one with a chronic Bell's palsy. The lesion was found incidentally in two cases (a suspected neurofibroma and a presumed drop metastasis from an astrocytoma). Patients with tumours had nodular, focally-enhancing lesions, except for the leptomeningeal metastasis in which the enhancement was linear. Linear, diffuse contrast enhancement of the facial nerve was found in trauma, and in the patient with a middle ear granuloma. Of the 24 patients with an acute Bell's palsy 15 exhibited linear contrast enhancement of the facial nerve. Three of these were lost to follow-up, but correlation of clinical outcome and contrast enhancement showed that only 4 of the 11 patients who made a complete recovery and all 10 patients with incomplete recovery demonstrated enhancement. Possible explanations for these findings are suggested by pathological data from the literature. 3D-FT imaging of the facial nerve thus yields direct information about the of the nerve condition and defines the morphological abnormalities. It can also demonstrate contrast enhancement which seems to have some prognostic value in acute idiopathic Bell's palsy. (orig.)

MRI of a family with focal abnormalities of gyration

International Nuclear Information System (INIS)

Muntaner, L.; Perez-Ferron, J.J.; Herrera, M.; Rosell, J.; Taboada, D.; Climent, S.

1997-01-01

Focal abnormalities of gyration (FAG) are developmental disorders that may occur in isolated patients or, as in the case being reported, as part of a familial disorder. Analysis of individuals in a family spanning three generations was carried out using MRI. Abnormalities, present in all members of generations II and III, included focal cortical dysplasia (three patients), focal cortical infolding (two patients) and schizencephaly (one patient); associated minor anomalies, such as white matter abnormalities, were seen in the remaining three members of generations II and III. MRI recognition of FAG in the family being reported proved useful in defining their phenotypical expression and providing proper counselling for individual family members. (orig.). With 6 figs

Clinical Application of 3D-CISS MRI Sequences for Diagnosis and Surgical Planning of Spinal Arachnoid Diverticula and Adhesions in Dogs.

Science.gov (United States)

Tauro, Anna; Jovanovik, Jelena; Driver, Colin John; Rusbridge, Clare

2018-02-01

 Abnormalities within the spinal arachnoid space are often treated surgically, but they can be challenging to detect with conventional magnetic resonance imaging (MRI) sequences. 3D-CISS sequences are considered superior in evaluating structures surrounded by cerebrospinal fluid (CSF) due to the high signal-to-noise ratio, high contrast-to-noise ratio and intrinsic insensitivity to motion with minimal signal loss due to CSF pulsations. Our objective was to describe findings and advantages in adding 3D-CISS sequences to routine MRI in patients affected by spinal arachnoid diverticula (SAD) or arachnoid adhesions.  This article is a retrospective review of medical records of 19 dogs admitted at Fitzpatrick Referrals between 2013 and 2017 that were diagnosed with SAD and confirmed surgically. Inclusion criterions were the presence of clinical signs compatible with compressive myelopathy and an MRI diagnosis, which included the 3D-CISS sequence. Our database was searched for additional 19 dogs diagnosed with other spinal lesions other than SAD that had the same MR sequences. All MR images were anonymized and evaluated by two assessors.  3D-CISS sequence appears to improve confidence in diagnosing and surgical planning (Mann-Whitney U -test: p  CSF hydrodynamics and providing more anatomical details than conventional MRI sequences. The clinical data in combination with imaging findings would limit over interpretation, when concurrent pathology within the arachnoid space is present. Schattauer GmbH Stuttgart.

SU-F-J-93: Automated Segmentation of High-Resolution 3D WholeBrain Spectroscopic MRI for Glioblastoma Treatment Planning

Energy Technology Data Exchange (ETDEWEB)

Schreibmann, E; Shu, H [Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA (United States); Cordova, J; Gurbani, S; Holder, C; Cooper, L; Shim, H [Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA (United States)

2016-06-15

Purpose: We report on an automated segmentation algorithm for defining radiation therapy target volumes using spectroscopic MR images (sMRI) acquired at nominal voxel resolution of 100 microliters. Methods: Wholebrain sMRI combining 3D echo-planar spectroscopic imaging, generalized auto-calibrating partially-parallel acquisitions, and elliptical k-space encoding were conducted on 3T MRI scanner with 32-channel head coil array creating images. Metabolite maps generated include choline (Cho), creatine (Cr), and N-acetylaspartate (NAA), as well as Cho/NAA, Cho/Cr, and NAA/Cr ratio maps. Automated segmentation was achieved by concomitantly considering sMRI metabolite maps with standard contrast enhancing (CE) imaging in a pipeline that first uses the water signal for skull stripping. Subsequently, an initial blob of tumor region is identified by searching for regions of FLAIR abnormalities that also display reduced NAA activity using a mean ratio correlation and morphological filters. These regions are used as starting point for a geodesic level-set refinement that adapts the initial blob to the fine details specific to each metabolite. Results: Accuracy of the segmentation model was tested on a cohort of 12 patients that had sMRI datasets acquired pre, mid and post-treatment, providing a broad range of enhancement patterns. Compared to classical imaging, where heterogeneity in the tumor appearance and shape across posed a greater challenge to the algorithm, sMRI’s regions of abnormal activity were easily detected in the sMRI metabolite maps when combining the detail available in the standard imaging with the local enhancement produced by the metabolites. Results can be imported in the treatment planning, leading in general increase in the target volumes (GTV60) when using sMRI+CE MRI compared to the standard CE MRI alone. Conclusion: Integration of automated segmentation of sMRI metabolite maps into planning is feasible and will likely streamline acceptance of this

3D-FT MRI of the facial nerve

Energy Technology Data Exchange (ETDEWEB)

Girard, N. (Neuroradiology, Hopital Nord, 13 Marseille (France)); Raybaud, C. (Neuroradiology, Hopital Nord, 13 Marseille (France)); Poncet, M. (Neuroradiology, Hopital Nord, 13 Marseille (France))

1994-08-01

Contrast-enhanced 3D-FT MRI of the intrapetrous facial nerve was obtained in 38 patients with facial nerve disease, using a 1.0 T magnet and fast gradient-echo acquisition sequences. Contiguous millimetric sections were obtained, which could be reformatted in any desired plane. Acutely ill patients, were examined within the first 2 months, included: 24 with Bell's palsy and 6 with other acute disorders (Herpes zoster, trauma, neuroma, meningeal metastasis, middle ear granuloma). Six patients investigated more than a year after the onset of symptoms included 3 with congenital cholesteatoma, 2 with neuromas and one with a chronic Bell's palsy. The lesion was found incidentally in two cases (a suspected neurofibroma and a presumed drop metastasis from an astrocytoma). Patients with tumours had nodular, focally-enhancing lesions, except for the leptomeningeal metastasis in which the enhancement was linear. Linear, diffuse contrast enhancement of the facial nerve was found in trauma, and in the patient with a middle ear granuloma. Of the 24 patients with an acute Bell's palsy 15 exhibited linear contrast enhancement of the facial nerve. Three of these were lost to follow-up, but correlation of clinical outcome and contrast enhancement showed that only 4 of the 11 patients who made a complete recovery and all 10 patients with incomplete recovery demonstrated enhancement. Possible explanations for these findings are suggested by pathological data from the literature. 3D-FT imaging of the facial nerve thus yields direct information about the of the nerve condition and defines the morphological abnormalities. It can also demonstrate contrast enhancement which seems to have some prognostic value in acute idiopathic Bell's palsy. (orig.)

Free breathing whole-heart 3D CINE MRI with self-gated Cartesian trajectory.

Science.gov (United States)

Usman, M; Ruijsink, B; Nazir, M S; Cruz, G; Prieto, C

2017-05-01

To present a method that uses a novel free-running self-gated acquisition to achieve isotropic resolution in whole heart 3D Cartesian cardiac CINE MRI. 3D cardiac CINE MRI using navigator gating results in long acquisition times. Recently, several frameworks based on self-gated non-Cartesian trajectories have been proposed to accelerate this acquisition. However, non-Cartesian reconstructions are computationally expensive due to gridding, particularly in 3D. In this work, we propose a novel highly efficient self-gated Cartesian approach for 3D cardiac CINE MRI. Acquisition is performed using CArtesian trajectory with Spiral PRofile ordering and Tiny golden angle step for eddy current reduction (so called here CASPR-Tiger). Data is acquired continuously under free breathing (retrospective ECG gating, no preparation pulses interruption) for 4-5min and 4D whole-heart volumes (3D+cardiac phases) with isotropic spatial resolution are reconstructed from all available data using a soft gating technique combined with temporal total variation (TV) constrained iterative SENSE reconstruction. For data acquired on eight healthy subjects and three patients, the reconstructed images using the proposed method had good contrast and spatio-temporal variations, correctly recovering diastolic and systolic cardiac phases. Non-significant differences (P>0.05) were observed in cardiac functional measurements obtained with proposed 3D approach and gold standard 2D multi-slice breath-hold acquisition. The proposed approach enables isotropic 3D whole heart Cartesian cardiac CINE MRI in 4 to 5min free breathing acquisition. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Development and Assessment of a New 3D Neuroanatomy Teaching Tool for MRI Training

Science.gov (United States)

Drapkin, Zachary A.; Lindgren, Kristen A.; Lopez, Michael J.; Stabio, Maureen E.

2015-01-01

A computerized three-dimensional (3D) neuroanatomy teaching tool was developed for training medical students to identify subcortical structures on a magnetic resonance imaging (MRI) series of the human brain. This program allows the user to transition rapidly between two-dimensional (2D) MRI slices, 3D object composites, and a combined model in…

Abnormal findings of magnetic resonance imaging (MRI) in patients with systemic lupus erythematosus involving the brain

Energy Technology Data Exchange (ETDEWEB)

Ishikawa, Akira; Okada, Jun; Kondo, Hirobumi (Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine); Kashiwazaki, Sadao

1992-06-01

To elucidate the clinical significance of MRI on central nervous system systemic lupus erythematosus (CNS-SLE), MRI and CT scans were performed in 35 patients with SLE, of 18 patients who had CNS manifestations at the time of MRI examinations. The investigations were also carried out in 17 patients without CNS-SLE. The rate of detection of abnormal findings on MRI in patients with CNS-SLE was 77.2% (14/18), which was high, as compared with the rate of those on CT scans (50%: 9/18). Especially, all of 4 patients with seizure and 3 patients with encephalopathy showed abnormal MRI findings, although respectively 50% and 33.3% of them had abnormal CT scan findings. MRI findings were classified into 4 groups below: (1) Large focal are as increased signal intensity at T2 weighted image. These were observed in 2 of 4 patients with seizure and 1 of 3 patients with encephalopathy, which were completely resolved after treatment. (2) Patchy subcortical foci of increased signal intensity at T2 weighted image. These were observed in 11 of 18 CNS-SLE and 7 of 17 without CNS-SLE, which were not detected by CT scan. (3) All of six patients with cerebral infarctions showed high signal intensity areas at T2 weighted image and low signal intensity areas at T1 weighted image. (4) Normal findings were observed in 4 of 18 CNS-SLE (22.2%). We concluded that MRI is useful for the evaluation of CNS-SLE and provides more information than CT scan. (author).

Abnormal findings of magnetic resonance imaging (MRI) in patients with systemic lupus erythematosus involving the brain

International Nuclear Information System (INIS)

Ishikawa, Akira; Okada, Jun; Kondo, Hirobumi; Kashiwazaki, Sadao.

1992-01-01

To elucidate the clinical significance of MRI on central nervous system systemic lupus erythematosus (CNS-SLE), MRI and CT scans were performed in 35 patients with SLE, of 18 patients who had CNS manifestations at the time of MRI examinations. The investigations were also carried out in 17 patients without CNS-SLE. The rate of detection of abnormal findings on MRI in patients with CNS-SLE was 77.2% (14/18), which was high, as compared with the rate of those on CT scans (50%: 9/18). Especially, all of 4 patients with seizure and 3 patients with encephalopathy showed abnormal MRI findings, although respectively 50% and 33.3% of them had abnormal CT scan findings. MRI findings were classified into 4 groups below: 1) Large focal are as increased signal intensity at T2 weighted image. These were observed in 2 of 4 patients with seizure and 1 of 3 patients with encephalopathy, which were completely resolved after treatment. 2) Patchy subcortical foci of increased signal intensity at T2 weighted image. These were observed in 11 of 18 CNS-SLE and 7 of 17 without CNS-SLE, which were not detected by CT scan. 3) All of six patients with cerebral infarctions showed high signal intensity areas at T2 weighted image and low signal intensity areas at T1 weighted image. 4) Normal findings were observed in 4 of 18 CNS-SLE (22.2%). We concluded that MRI is useful for the evaluation of CNS-SLE and provides more information than CT scan. (author)

Posterior fossa abnormalities in high-risk term infants: comparison of ultrasound and MRI

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Steggerda, S.J.; Smits-Wintjens, V.E.H.J.; Verbon, P.; Walther, F.J. [Leiden University Medical Centre, Department of Neonatology, Leiden (Netherlands); Bruine, F.T. de [Leiden University Medical Centre, Department of Radiology, Leiden (Netherlands); Wezel-Meijler, G. van [Leiden University Medical Centre, Department of Radiology, Leiden (Netherlands); Isala Hospital, Department of Neonatology, Zwolle (Netherlands)

2015-09-15

We aimed to assess the characteristics of posterior fossa (PF) abnormalities in a cohort of high-risk term neonates, as well as the diagnostic performance of cranial ultrasound (CUS) with additional mastoid fontanelle (MF) views for the detection of these abnormalities, with magnetic resonance imaging (MRI) being the reference standard. In this retrospective study, 113 term neonates with CUS and subsequent MRI were included. Sensitivity, specificity, and predictive values of routine CUS and CUS with MF views were calculated. Posterior fossa abnormalities were diagnosed on CUS in 46 of 113 infants. MRI confirmed these findings in 43 and showed additional abnormalities in 32 infants. The sensitivity and specificity of anterior fontanelle views for major PF abnormalities as seen on MRI were 16 % and 99 %. Adding MF views increased the sensitivity of US to 82 %. The sensitivity and specificity of MF views for the detection of any (major or minor) PF abnormality were 57 % and 95 %. Especially acute hypoxic-ischemic injury and small subdural and punctate cerebellar haemorrhage remained undetected by CUS. PF abnormalities are frequent in high-risk term infants. MF-CUS enables early diagnosis of major PF abnormalities. We therefore advocate to perform MF-CUS in high-risk term neonates. (orig.)

Posterior fossa abnormalities in high-risk term infants: comparison of ultrasound and MRI

International Nuclear Information System (INIS)

Steggerda, S.J.; Smits-Wintjens, V.E.H.J.; Verbon, P.; Walther, F.J.; Bruine, F.T. de; Wezel-Meijler, G. van

2015-01-01

We aimed to assess the characteristics of posterior fossa (PF) abnormalities in a cohort of high-risk term neonates, as well as the diagnostic performance of cranial ultrasound (CUS) with additional mastoid fontanelle (MF) views for the detection of these abnormalities, with magnetic resonance imaging (MRI) being the reference standard. In this retrospective study, 113 term neonates with CUS and subsequent MRI were included. Sensitivity, specificity, and predictive values of routine CUS and CUS with MF views were calculated. Posterior fossa abnormalities were diagnosed on CUS in 46 of 113 infants. MRI confirmed these findings in 43 and showed additional abnormalities in 32 infants. The sensitivity and specificity of anterior fontanelle views for major PF abnormalities as seen on MRI were 16 % and 99 %. Adding MF views increased the sensitivity of US to 82 %. The sensitivity and specificity of MF views for the detection of any (major or minor) PF abnormality were 57 % and 95 %. Especially acute hypoxic-ischemic injury and small subdural and punctate cerebellar haemorrhage remained undetected by CUS. PF abnormalities are frequent in high-risk term infants. MF-CUS enables early diagnosis of major PF abnormalities. We therefore advocate to perform MF-CUS in high-risk term neonates. (orig.)

Anisotropic Diffusion based Brain MRI Segmentation and 3D Reconstruction

OpenAIRE

M. Arfan Jaffar; Sultan Zia; Ghaznafar Latif; AnwarM. Mirza; Irfan Mehmood; Naveed Ejaz; Sung Wook Baik

2012-01-01

In medical field visualization of the organs is very imperative for accurate diagnosis and treatment of any disease. Brain tumor diagnosis and surgery also required impressive 3D visualization of the brain to the radiologist. Detection and 3D reconstruction of brain tumors from MRI is a computationally time consuming and error-prone task. Proposed system detects and presents a 3D visualization model of the brain and tumor inside which greatly helps the radiologist to effectively diagnose and ...

Transient MRI abnormalities associated with partial status epilepticus: a case report

Energy Technology Data Exchange (ETDEWEB)

Amato, Carmelo; Elia, Maurizio; Musumeci, Sebastiano A; Bisceglie, Pierluigi; Moschini, Massimo

2001-04-01

We report the case of an 18-year-old woman who presented a long-lasting cluster of partial seizures, and MRI cortical abnormalities localized in the left parietal lobe. The MRI changes correlated with the site of the epileptogenic focus, and disappeared within 2 weeks. The recognition of these reversible MRI abnormalities, which are presumably due to a temporary alteration of blood-brain barrier in the epileptogenic zone with subsequent edema, and are not associated with any underlying organic conditions, is extremely useful in the medical management of the patient and allows to avoid other invasive diagnostic procedures.

Transient MRI abnormalities associated with partial status epilepticus: a case report

International Nuclear Information System (INIS)

Amato, Carmelo; Elia, Maurizio; Musumeci, Sebastiano A.; Bisceglie, Pierluigi; Moschini, Massimo

2001-01-01

We report the case of an 18-year-old woman who presented a long-lasting cluster of partial seizures, and MRI cortical abnormalities localized in the left parietal lobe. The MRI changes correlated with the site of the epileptogenic focus, and disappeared within 2 weeks. The recognition of these reversible MRI abnormalities, which are presumably due to a temporary alteration of blood-brain barrier in the epileptogenic zone with subsequent edema, and are not associated with any underlying organic conditions, is extremely useful in the medical management of the patient and allows to avoid other invasive diagnostic procedures

The usefulness of 3D quantitative analysis with using MRI for measuring osteonecrosis of the femoral head

International Nuclear Information System (INIS)

Hwang, Ji Young; Lee, Sun Wha; Park, Youn Soo

2006-01-01

We wanted to evaluate the usefulness of MRI 3D quantitative analysis for measuring osteonecrosis of the femoral head in comparison with MRI 2D quantitative analysis and quantitative analysis of the specimen. For 3 months at our hospital, 14 femoral head specimens with osteonecrosis were obtained after total hip arthroplasty. The patients preoperative MRIs were retrospectively reviewed for quantitative analysis of the size of the necrosis. Each necrotic fraction of the femoral head was measured by 2D quantitative analysis with using mid-coronal and mid-sagittal MRIs, and by 3D quantitative analysis with using serial continuous coronal MRIs and 3D reconstruction software. The necrotic fraction of the specimen was physically measured by the fluid displacement method. The necrotic fraction according to MRI 2D or 3D quantitative analysis was compared with that of the specimen by using Spearman's correlation test. On the correlative analysis, the necrotic fraction by MRI 2D quantitative analysis and quantitative analysis of the specimen showed moderate correlation (r = 0.657); on the other hand, the necrotic fraction by MRI 3D quantitative analysis and quantitative analysis of the specimen demonstrated a strong correlation (r = 0.952) (ρ < 0.05). MRI 3D quantitative analysis was more accurate than 2D quantitative analysis using MRI for measuring osteonecrosis of the femoral head. Therefore, it may be useful for predicting the clinical outcome and deciding the proper treatment option

Comparison of X-ray, CT and MRI in detection of abnormal sacroiliac joint changes in patients with early stage of ankylosing spondylitis

International Nuclear Information System (INIS)

Huang Zhenguo; Zhang Xuezhe; Hong Wen; Wang Guochun; Zhou Huiqiong; Lu Xin; Wang Wu

2011-01-01

Objective: To compare X-ray, CT, and MRI in detection of abnormal sacroiliac joint changes in patients with early stage of ankylosing spondylitis (AS). Methods: Fifty-three patients with clinical suspected early stage of AS underwent X-ray and MRI scan. MR scan sequences for the sacroiliac joints consisted of T 1 -weighted, T 2 -weighted, short time inversion recovery (STIR) and three dimensional balance turbo field echo with water selective excitation (3D-BTFE-WATS) in all patients. In 24 of the patients, fat-saturated contrast-enhanced T 1 -weighted was used. Twenty-five of 53 patients underwent CT scan. The Chi-square test was used to analyse the uniformity of bone erosions detected by X-ray, CT, and MRI. Results: Of the 106 sacroiliac joints in 53 patients, 16 sacroiliac joints with bone erosions were detected by X-ray and 63 sacroiliac joints by MRI. Of the 50 sacroiliac joints in 25 patients, 26 sacroiliac joints with bone erosions were found by CT. With regard to the detection of bone erosions, there was no difference between Cf and MRI (χ 2 =0.16, P>0.05) and there was significant difference between CT and X-ray or MRI and X-ray (χ 2 =14.44 and 17.36, P<0.05). 3D-BTFE-WATS was better than other sequences in detection of bone erosions. Acute inflammatory changes were determined by MRI, which included subchondral bone marrow edema in 32 patients, synovitis in 35 patients, fat depositions in 16 patients, enthesitis in 15 patients, capsulitis in 9 patients, and cartilaginous disruption in 31 patients. Conclusions: MRI can detect acute inflammatory changes that can not display by X-ray and CT. Compared with radiography and CT, MRI is more useful in detection of abnormal sacroiliac joint changes in patients with early stage of AS. (authors)

Prospective comparison of 3D FIESTA versus fat-suppressed 3D SPGR MRI in evaluating knee cartilage lesions

International Nuclear Information System (INIS)

Li, X.; Yu, C.; Wu, H.; Daniel, K.; Hu, D.; Xia, L.; Pan, C.; Xu, A.; Hu, J.; Wang, L.; Peng, W.; Li, F.

2009-01-01

Aim: To prospectively compare the accuracy of three-dimensional fast imaging employing steady-state acquisition (3D FIESTA) sequences with that of fat-suppressed three-dimensional spoiled gradient-recalled (3D SPGR) in the diagnosis of knee articular cartilage lesions, using arthroscopy as the reference standard. Materials and methods: Fifty-eight knees in 54 patients (age range 21-82 years; mean 36 years) were prospectively evaluated by using sagittal 3D FIESTA and sagittal fat-suppressed 3D SPGR sequences. Articular cartilage lesions were graded on MRI and during arthroscopy with a modified Noyes scoring system. Sensitivity, specificity, and accuracy were assessed. Interobserver agreement was determined with κ statistics. Results: The performance of 3D FIESTA sequences (sensitivity, specificity, and accuracy were 80, 94, and 92%, respectively, for reader 1 and 76, 94, and 90%, respectively, for reader 2) was similar to that of fat-suppressed 3D SPGR sequences (sensitivity, specificity, and accuracy were 82, 92, and 90%, respectively, for reader 1 and 82, 90, and 88%, respectively, for reader 2) in the detection of knee articular cartilage lesions. The interobserver agreement varied from fair to good to excellent (kappa values from 0.43-0.83). Conclusion: 3D FIESTA has good diagnostic performance, comparable with fat-suppressed 3D SPGR in evaluating knee cartilage lesions, and it can be incorporated into routine knee MRI protocols due to the short acquisition time.

Prospective comparison of 3D FIESTA versus fat-suppressed 3D SPGR MRI in evaluating knee cartilage lesions

Energy Technology Data Exchange (ETDEWEB)

Li, X.; Yu, C. [Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030 (China); Wu, H. [Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030 (China)], E-mail: lilyboston2002@163.com; Daniel, K. [Department of Radiology, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Hu, D.; Xia, L.; Pan, C.; Xu, A.; Hu, J.; Wang, L.; Peng, W. [Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030 (China); Li, F. [Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030 (China)

2009-10-15

Aim: To prospectively compare the accuracy of three-dimensional fast imaging employing steady-state acquisition (3D FIESTA) sequences with that of fat-suppressed three-dimensional spoiled gradient-recalled (3D SPGR) in the diagnosis of knee articular cartilage lesions, using arthroscopy as the reference standard. Materials and methods: Fifty-eight knees in 54 patients (age range 21-82 years; mean 36 years) were prospectively evaluated by using sagittal 3D FIESTA and sagittal fat-suppressed 3D SPGR sequences. Articular cartilage lesions were graded on MRI and during arthroscopy with a modified Noyes scoring system. Sensitivity, specificity, and accuracy were assessed. Interobserver agreement was determined with {kappa} statistics. Results: The performance of 3D FIESTA sequences (sensitivity, specificity, and accuracy were 80, 94, and 92%, respectively, for reader 1 and 76, 94, and 90%, respectively, for reader 2) was similar to that of fat-suppressed 3D SPGR sequences (sensitivity, specificity, and accuracy were 82, 92, and 90%, respectively, for reader 1 and 82, 90, and 88%, respectively, for reader 2) in the detection of knee articular cartilage lesions. The interobserver agreement varied from fair to good to excellent (kappa values from 0.43-0.83). Conclusion: 3D FIESTA has good diagnostic performance, comparable with fat-suppressed 3D SPGR in evaluating knee cartilage lesions, and it can be incorporated into routine knee MRI protocols due to the short acquisition time.

Motion robust high resolution 3D free-breathing pulmonary MRI using dynamic 3D image self-navigator.

Science.gov (United States)

Jiang, Wenwen; Ong, Frank; Johnson, Kevin M; Nagle, Scott K; Hope, Thomas A; Lustig, Michael; Larson, Peder E Z

2018-06-01

To achieve motion robust high resolution 3D free-breathing pulmonary MRI utilizing a novel dynamic 3D image navigator derived directly from imaging data. Five-minute free-breathing scans were acquired with a 3D ultrashort echo time (UTE) sequence with 1.25 mm isotropic resolution. From this data, dynamic 3D self-navigating images were reconstructed under locally low rank (LLR) constraints and used for motion compensation with one of two methods: a soft-gating technique to penalize the respiratory motion induced data inconsistency, and a respiratory motion-resolved technique to provide images of all respiratory motion states. Respiratory motion estimation derived from the proposed dynamic 3D self-navigator of 7.5 mm isotropic reconstruction resolution and a temporal resolution of 300 ms was successful for estimating complex respiratory motion patterns. This estimation improved image quality compared to respiratory belt and DC-based navigators. Respiratory motion compensation with soft-gating and respiratory motion-resolved techniques provided good image quality from highly undersampled data in volunteers and clinical patients. An optimized 3D UTE sequence combined with the proposed reconstruction methods can provide high-resolution motion robust pulmonary MRI. Feasibility was shown in patients who had irregular breathing patterns in which our approach could depict clinically relevant pulmonary pathologies. Magn Reson Med 79:2954-2967, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Evaluation of Brain and Cervical MRI Abnormality Rates in Patients With Systemic Lupus Erythematosus With or Without Neurological Manifestations

International Nuclear Information System (INIS)

Harirchian, Mohammad Hossein; Saberi, Hazhir; Najafizadeh, Seyed Reza; Hashemi, Seyed Ali

2011-01-01

Central nervous system (CNS) involvement has been observed in 14-80% of patients with systemic lupus erythematosus (SLE). Magnetic resonance imaging (MRI) is an appropriate method for evaluating CNS involvement in these patients. Clinical manifestations and MRI findings of CNS lupus should be differentiated from other mimicking diseases such as multiple sclerosis (MS). The aim of this study was to evaluate the prevalence and extent of brain and cervical cord MRI lesions of lupus patients. The relationship between neurological signs and symptoms and MRI findings were evaluated as well. Fifty SLE patients who had been referred to the rheumatology clinic of our hospital within 2009 were included in a cross sectional study. All patients fulfilled the revised 1981 American College of Rheumatology (ACR) criteria for SLE. We evaluated the neurological signs and symptoms and brain and cervical MRI findings in these patients. Forty-one patients (82%) were female and nine (18%) were male. The mean age was 30.1 ± 9.3 years. Twenty eight (56%) patients had an abnormal brain MRI. No one showed any abnormality in the cervical MRI. The lesions in 20 patients were similar to demyelinative plaques. Seventeen patients with abnormal brain MRI were neurologically asymptomatic. There was only a significant relationship between neurological motor manifestations and brain MRI abnormal findings. Unlike the brain, cervical MRI abnormality and especially asymptomatic cord involvement in MRI is quite rare in SLE patients. This finding may be helpful to differentiate SLE from other CNS disorders such as MS

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.)

Intraspinal neural axis abnormalities in severe spinal deformity: a 10-year MRI review.

Science.gov (United States)

Zhang, Ying; Xie, Jingming; Wang, Yingsong; Bi, Ni; Li, Tao; Zhang, Jie; Zhao, Zhi; Ou, Hua; Liu, Siyuan

2018-02-14

Documents indicated that the average prevalence of intraspinal neural axis abnormalities (INAAs) in presumed idiopathic scoliosis (PIS) patients was about 17.7%. However, paucity study focuses on the incidence of INAAs in severe spinal deformity (SSDs). In this study, we investigate the incidence of intraspinal neural axis abnormalities (IINAAs) and the clinical relevance in SSD at a single center. All the patients with SSDs admitted for spinal surgery were evaluated from 2003 to 2014. patients who present with coronal Cobb over 90° (and/or the sagittal Cobb ≥ 90°); patients with whole spine magnetic resonance imaging (MRI) done preoperatively; and patients with documented clinical findings preoperatively. ankylosing spondylitis, adult onset scoliosis, scoliosis secondary to bone destruction, and spinal dysraphism. 101 patients fulfilled the criteria were included. 43 patients were detected with INAAs (42.6%, 43/101). The most common INAAs was syrinx (S) (16/43, 37.2%). Of which, 43.7% (7/16), 37.5% (6/16), and 18.7% (3/16) were spindle, slit, and swelling types, respectively. Most of them were located in thoracic (6/16, 37.5%) and cervical (5/16, 31.3%) region. MRI revealed Chiari malformation with syringomyelia (C + S) in ten patients (10/43, 23.2%), Chiari malformation (C) in 6 patients (6/43, 13.9%) and others in 11 patients (11/43, 25.6%). As to the etiology, most patients with INAAs were PIS (34/43, 79.1%). On clinical examination, 16 of 101 patients (16/101, 15.8%) had abnormal neurologic signs. 15 of 16 patients (15/16, 93.7%) with abnormal neurologic signs had INAAs on MRI. On the other hand, 28 of 43 patients (28/43, 65.1%) with INAAs on MRI presented neurologically intact. 28 of 85 patients (28/85, 32.9%) with neurologically intact were detected with INAAs on MRI. The incidence of INAAs in SSDs was 42.6%. 65.1% of them present intact neurologic status. The most common neural anomaly was syrinx. Preoperative whole spine MRI must be beneficial for

Multi-feature-based plaque characterization in ex vivo MRI trained by registration to 3D histology

International Nuclear Information System (INIS)

Van Engelen, Arna; Niessen, Wiro J; Klein, Stefan; De Bruijne, Marleen; Groen, Harald C; Wentzel, Jolanda J; Verhagen, Hence JM; Lugt, Aad van der

2012-01-01

We present a new method for automated characterization of atherosclerotic plaque composition in ex vivo MRI. It uses MRI intensities as well as four other types of features: smoothed, gradient magnitude and Laplacian images at several scales, and the distances to the lumen and outer vessel wall. The ground truth for fibrous, necrotic and calcified tissue was provided by histology and μCT in 12 carotid plaque specimens. Semi-automatic registration of a 3D stack of histological slices and μCT images to MRI allowed for 3D rotations and in-plane deformations of histology. By basing voxelwise classification on different combinations of features, we evaluated their relative importance. To establish whether training by 3D registration yields different results than training by 2D registration, we determined plaque composition using (1) a 2D slice-based registration approach for three manually selected MRI and histology slices per specimen, and (2) an approach that uses only the three corresponding MRI slices from the 3D-registered volumes. Voxelwise classification accuracy was best when all features were used (73.3 ± 6.3%) and was significantly better than when only original intensities and distance features were used (Friedman, p < 0.05). Although 2D registration or selection of three slices from the 3D set slightly decreased accuracy, these differences were non-significant. (paper)

3D-visualization by MRI for surgical planning of Wilms tumors; 3-D-Visualisierung in der MRT zur Operationsplanung von Wilms-Tumoren

Energy Technology Data Exchange (ETDEWEB)

Schenk, J.P.; Wunsch, R.; Jourdan, C.; Troeger, J. [Universitaetsklinik Heidelberg (Germany). Abteilung Paediatrische Radiologie; Waag, K.-L.; Guenther, P. [Universitaetsklinik Heidelberg (Germany). Abteilung Kinderchirurgie; Graf, N. [Universitaetsklinik Homburg (Germany). Abteilung Paediatrische Haematologie und Onkologie; Behnisch, W. [Universitaetsklinik Heidelberg (Germany). Abteilung Paediatrische Haematologie und Onkologie

2004-10-01

Purpose: To improve surgical planning of kidney tumors in childhood (Wilms tumor, mesoblastic nephroma) after radiologic verification of the presumptive diagnosis with interactive colored 3D-animation in MRI. Materials and Methods: In 7 children (1 boy, 6 girls) with a mean age of 3 years (1 month to 11 years), the MRI database (DICOM) was processed with a raycasting-based 3D-volume-rendering software (VG Studio Max 1.1/Volume Graphics). The abdominal MRI-sequences (coronal STIR, coronal T1 TSE, transverse T1/T2 TSE, sagittal T2 TSE, transverse and coronal T1 TSE post contrast) were obtained with a 0.5T unit in 4-6 mm slices. Additionally, phase-contrast-MR-angiography was applied to delineate the large abdominal and retroperitoneal vessels. A notebook was used to demonstrate the 3D-visualization for surgical planning before surgery and during the surgical procedure. Results: In all 7 cases, the surgical approach was influenced by interactive 3D-animation and the information found useful for surgical planning. Above all, the 3D-visualization demonstrates the mass effect of the Wilms tumor and its anatomical relationship to the renal hilum and to the rest of the kidney as well as the topographic relationship of the tumor to the critical vessels. One rupture of the tumor capsule occurred as a surgical complication. For the surgeon, the transformation of the anatomical situation from MRI to the surgical situs has become much easier. Conclusion: For surgical planning of Wilms tumors, the 3D-visualization with 3D-animation of the situs helps to transfer important information from the pediatric radiologist to the pediatric surgeon and optimizes the surgical preparation. A reduction of complications is to be expected. (orig.)

Facilitating tumor functional assessment by spatially relating 3D tumor histology and in vivo MRI: image registration approach.

Directory of Open Access Journals (Sweden)

Lejla Alic

Full Text Available BACKGROUND: Magnetic resonance imaging (MRI, together with histology, is widely used to diagnose and to monitor treatment in oncology. Spatial correspondence between these modalities provides information about the ability of MRI to characterize cancerous tissue. However, registration is complicated by deformations during pathological processing, and differences in scale and information content. METHODOLOGY/PRINCIPAL FINDINGS: This study proposes a methodology for establishing an accurate 3D relation between histological sections and high resolution in vivo MRI tumor data. The key features of the methodology are: 1 standardized acquisition and processing, 2 use of an intermediate ex vivo MRI, 3 use of a reference cutting plane, 4 dense histological sampling, 5 elastic registration, and 6 use of complete 3D data sets. Five rat pancreatic tumors imaged by T2*-w MRI were used to evaluate the proposed methodology. The registration accuracy was assessed by root mean squared (RMS distances between manually annotated landmark points in both modalities. After elastic registration the average RMS distance decreased from 1.4 to 0.7 mm. The intermediate ex vivo MRI and the reference cutting plane shared by all three 3D images (in vivo MRI, ex vivo MRI, and 3D histology data were found to be crucial for the accurate co-registration between the 3D histological data set and in vivo MRI. The MR intensity in necrotic regions, as manually annotated in 3D histology, was significantly different from other histologically confirmed regions (i.e., viable and hemorrhagic. However, the viable and the hemorrhagic regions showed a large overlap in T2(*-w MRI signal intensity. CONCLUSIONS: The established 3D correspondence between tumor histology and in vivo MRI enables extraction of MRI characteristics for histologically confirmed regions. The proposed methodology allows the creation of a tumor database of spatially registered multi-spectral MR images and multi-stained 3D

Qualitative and quantitative assessment of wrist MRI at 3.0T - Comparison between isotropic 3D turbo spin echo and isotropic 3D fast field echo and 2D turbo spin echo

International Nuclear Information System (INIS)

Jung, Jee Young; Yoon, Young Cheol; Jung, Jin Young; Choe, Bong-Keun

2013-01-01

Background: Isotropic three-dimensional (3D) magnetic resonance imaging (MRI) has been applied to various joints. However, comparison for image quality between isotropic 3D MRI and two-dimensional (2D) turbo spin echo (TSE) sequence of the wrist at a 3T MR system has not been investigated. Purpose: To compare the image quality of isotropic 3D MRI including TSE intermediate-weighted (VISTA) sequence and fast field echo (FFE) sequence with 2D TSE intermediate-weighted sequence of the wrist joint at 3.0 T. Material and Methods: MRI was performed in 10 wrists of 10 healthy volunteers with isotropic 3D sequences (VISTA and FFE) and 2D TSE intermediate-weighted sequences at 3.0 T. The signal-to-noise ratio (SNR) was obtained by imaging phantom and noise-only image. Contrast ratios (CRs) were calculated between fluid and cartilage, triangular fibrocartilage complex (TFCC), and the scapholunate ligament. Two radiologists independently assessed the visibility of TFCC, carpal ligaments, cartilage, tendons and nerves with a four-point grading scale. Statistical analysis to compare CRs (one way ANOVA with a Tukey test) and grades of visibility (Kruskal-Wallis test) between three sequences and those for inter-observer agreement (kappa analysis) were performed. Results: The SNR of 2D TSE (46.26) was higher than those of VISTA (23.34) and 3D FFE (19.41). CRs were superior in 2D TSE than VISTA (P = 0.02) for fluid-cartilage and in 2D TSE than 3D FFE (P < 0.01) for fluid-TFCC. The visibility was best in 2D TSE (P < 0.01) for TFCC and in VISTA (P = 0.01) for scapholunate ligament. The visibility was better in 2D TSE and 3D FFE (P 0.04) for cartilage and in VISTA than 3D FFE (P < 0.01) for TFCC. The inter-observer agreement for the visibility of anatomic structures was moderate or substantial. Conclusion: Image quality of 2D TSE was superior to isotropic 3D MR imaging for cartilage, and TFCC. 3D FFE has better visibility for cartilage than VISTA and VISTA has superior visibility for

Qualitative and quantitative assessment of wrist MRI at 3.0T - Comparison between isotropic 3D turbo spin echo and isotropic 3D fast field echo and 2D turbo spin echo

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Jung, Jee Young [Dept. of Radiology, Chungang Univ. Hospital, School of Medicine, Chungang Univ. (Korea, Republic of); Yoon, Young Cheol [Dept. of Radiology, Samsung Medical Center, School of Medicine, Sungkyunkwan Univ. (Korea, Republic of)], e-mail: ycyoon@skku.edu; Jung, Jin Young [Dept. of Radiology, Saint Paul' s Hospital, The Catholic Univ. (Korea, Republic of); Choe, Bong-Keun [Dept. of Preventive Medicine, School of Medicine, Kyung Hee Univ., Seoul (Korea, Republic of)

2013-04-15

Background: Isotropic three-dimensional (3D) magnetic resonance imaging (MRI) has been applied to various joints. However, comparison for image quality between isotropic 3D MRI and two-dimensional (2D) turbo spin echo (TSE) sequence of the wrist at a 3T MR system has not been investigated. Purpose: To compare the image quality of isotropic 3D MRI including TSE intermediate-weighted (VISTA) sequence and fast field echo (FFE) sequence with 2D TSE intermediate-weighted sequence of the wrist joint at 3.0 T. Material and Methods: MRI was performed in 10 wrists of 10 healthy volunteers with isotropic 3D sequences (VISTA and FFE) and 2D TSE intermediate-weighted sequences at 3.0 T. The signal-to-noise ratio (SNR) was obtained by imaging phantom and noise-only image. Contrast ratios (CRs) were calculated between fluid and cartilage, triangular fibrocartilage complex (TFCC), and the scapholunate ligament. Two radiologists independently assessed the visibility of TFCC, carpal ligaments, cartilage, tendons and nerves with a four-point grading scale. Statistical analysis to compare CRs (one way ANOVA with a Tukey test) and grades of visibility (Kruskal-Wallis test) between three sequences and those for inter-observer agreement (kappa analysis) were performed. Results: The SNR of 2D TSE (46.26) was higher than those of VISTA (23.34) and 3D FFE (19.41). CRs were superior in 2D TSE than VISTA (P = 0.02) for fluid-cartilage and in 2D TSE than 3D FFE (P < 0.01) for fluid-TFCC. The visibility was best in 2D TSE (P < 0.01) for TFCC and in VISTA (P = 0.01) for scapholunate ligament. The visibility was better in 2D TSE and 3D FFE (P 0.04) for cartilage and in VISTA than 3D FFE (P < 0.01) for TFCC. The inter-observer agreement for the visibility of anatomic structures was moderate or substantial. Conclusion: Image quality of 2D TSE was superior to isotropic 3D MR imaging for cartilage, and TFCC. 3D FFE has better visibility for cartilage than VISTA and VISTA has superior visibility for

Hypomelanosis of Ito and brain abnormalities: MRI findings and literature review

International Nuclear Information System (INIS)

Steiner, J.; Adamsbaum, C.; Desguerres, I.; Lalande, G.; Raynaud, F.; Ponsot, G.; Kalifa, G.

1996-01-01

We report the results of a 14-year retrospective study of brain MRI abnormalities in 12 pediatric patients presenting with hypomelanosis of Ito (HI). Miscellaneous brain abnormalities were found: one patient had a medulloblastoma, three had cortical malformations, and five demonstrated ''minor'' abnormalities such as dilated Virchow-Robin spaces or brain atrophy. We emphasize the polymorphism of brain abnormalities associated with HI. (orig.). With 5 figs., 1 tab

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

MRI abnormalities of sacroiliac joints in early spondylarthropathy

DEFF Research Database (Denmark)

Puhakka, K B; Jurik, A G; Schiøttz-Christensen, Berit

2004-01-01

OBJECTIVE: To describe changes in chronic and acute magnetic resonance imaging (MRI) abnormalities of the sacroiliac joints (SIJs) in early spondylarthropathy (SpA), and to associate these findings with computed tomography (CT), X-ray, and clinical findings during a 1-year follow-up. METHODS...

Imaging of prostate cancer: a platform for 3D co-registration of in-vivo MRI ex-vivo MRI and pathology

Science.gov (United States)

Orczyk, Clément; Mikheev, Artem; Rosenkrantz, Andrew; Melamed, Jonathan; Taneja, Samir S.; Rusinek, Henry

2012-02-01

Objectives: Multi-parametric MRI is emerging as a promising method for prostate cancer diagnosis. prognosis and treatment planning. However, the localization of in-vivo detected lesions and pathologic sites of cancer remains a significant challenge. To overcome this limitation we have developed and tested a system for co-registration of in-vivo MRI, ex-vivo MRI and histology. Materials and Methods: Three men diagnosed with localized prostate cancer (ages 54-72, PSA levels 5.1-7.7 ng/ml) were prospectively enrolled in this study. All patients underwent 3T multi-parametric MRI that included T2W, DCEMRI, and DWI prior to robotic-assisted prostatectomy. Ex-vivo multi-parametric MRI was performed on fresh prostate specimen. Excised prostates were then sliced at regular intervals and photographed both before and after fixation. Slices were perpendicular to the main axis of the posterior capsule, i.e., along the direction of the rectal wall. Guided by the location of the urethra, 2D digital images were assembled into 3D models. Cancer foci, extra-capsular extensions and zonal margins were delineated by the pathologist and included in 3D histology data. A locally-developed software was applied to register in-vivo, ex-vivo and histology using an over-determined set of anatomical landmarks placed in anterior fibro-muscular stroma, central. transition and peripheral zones. The mean root square distance across corresponding control points was used to assess co-registration error. Results: Two specimens were pT3a and one pT2b (negative margin) at pathology. The software successfully fused invivo MRI. ex-vivo MRI fresh specimen and histology using appropriate (rigid and affine) transformation models with mean square error of 1.59 mm. Coregistration accuracy was confirmed by multi-modality viewing using operator-guided variable transparency. Conclusion: The method enables successful co-registration of pre-operative MRI, ex-vivo MRI and pathology and it provides initial evidence

MRI of Neurosyphilis Presenting as Mesiotemporal Abnormalities: a Case Report

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Jeong, Yu Mi; Hwang, Hee Young; Kim, Hyung Sik [Gachon University, Gil Medical Center, Incheon (Korea, Republic of)

2009-06-15

The high signal intensities in bilateral mesiotemporal lobes on T2-weighted images are typical findings of herpes encephalitis or paraneoplastic limbic encephalitis. We report a case of neurosyphilis with mesiotemporal involvement on MRI. Positive antibodies in the cerebrospinal fluid confirmed the diagnosis. The results suggest that neurosyphilis should be considered when MRI results indicate mesiotemporal abnormalities.

Is it possible to model the risk of malignancy of focal abnormalities found at prostate multiparametric MRI?

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Rouviere, Olivier [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Lyon (France); Universite de Lyon, Lyon (France); Universite Lyon 1, faculte de medecine Lyon Est, Lyon (France); Inserm, U556, Lyon (France); Pavillon P Radio, Hopital Edouard Herriot, Department of Urinary and Vascular Radiology, Lyon Cedex 03 (France); Papillard, Matthieu; Girouin, Nicolas; Boutier, Romain [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Lyon (France); Universite de Lyon, Lyon (France); Universite Lyon 1, faculte de medecine Lyon Est, Lyon (France); Rabilloud, Muriel; Riche, Benjamin [Hospices Civils de Lyon, Department of Biostatistics, Lyon (France); Universite Lyon 1, UMR CNRS 5558, Laboratoire Biostatistiques-Sante, Pierre-Benite (France); Mege-Lechevallier, Florence [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Pathology, Lyon (France); Colombel, Marc [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urology, Lyon (France); Gelet, Albert [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urology, Lyon (France); Inserm, U556, Lyon (France)

2012-05-15

To evaluate whether focal abnormalities (FAs) depicted by prostate MRI could be characterised using simple semiological features. 134 patients who underwent T2-weighted, diffusion-weighted and dynamic contrast-enhanced MRI at 1.5 T before prostate biopsy were prospectively included. FAs visible at MRI were characterised by their shape, the degree of signal abnormality (0 = normal to 3 = markedly abnormal) on individual MR sequences, and a subjective score (SS{sub 1} = probably benign to SS{sub 3} = probably malignant). FAs were then biopsied under US guidance. 56/233 FAs were positive at biopsy. The subjective score significantly predicted biopsy results (P < 0.01). As compared to SS{sub 1} FAs, the odds ratios (OR) of malignancy of SS{sub 2} and SS{sub 3} FAs were 9.9 (1.8-55.9) and 163.8 (11.5-2331). Unlike FAs' shape, a simple combination of MR signal abnormalities (into ''low-risk'', ''intermediate'' and ''high-risk'' groups) significantly predicted biopsy results (P < 0.008). As compared to ''low risk'' FAs, the OR of malignancy of ''intermediate'' and ''high-risk'' FAs were 4.5 (1.1-18.4) and 52.7 (6.8-407) in the overall population and 5.4 (1.1-27.2) and 118.2 (6.1-2301) in PZ. A simple combination of signal abnormalities of individual MR sequences can significantly stratify the risk of malignancy of FAs, holding promise of a more standardised interpretation of MRI by readers with varying experience. (orig.)

Custom fit 3D-printed brain holders for comparison of histology with MRI in marmosets.

Science.gov (United States)

Guy, Joseph R; Sati, Pascal; Leibovitch, Emily; Jacobson, Steven; Silva, Afonso C; Reich, Daniel S

2016-01-15

MRI has the advantage of sampling large areas of tissue and locating areas of interest in 3D space in both living and ex vivo systems, whereas histology has the ability to examine thin slices of ex vivo tissue with high detail and specificity. Although both are valuable tools, it is currently difficult to make high-precision comparisons between MRI and histology due to large differences inherent to the techniques. A method combining the advantages would be an asset to understanding the pathological correlates of MRI. 3D-printed brain holders were used to maintain marmoset brains in the same orientation during acquisition of ex vivo MRI and pathologic cutting of the tissue. The results of maintaining this same orientation show that sub-millimeter, discrete neuropathological features in marmoset brain consistently share size, shape, and location between histology and ex vivo MRI, which facilitates comparison with serial imaging acquired in vivo. Existing methods use computational approaches sensitive to data input in order to warp histologic images to match large-scale features on MRI, but the new method requires no warping of images, due to a preregistration accomplished in the technique, and is insensitive to data formatting and artifacts in both MRI and histology. The simple method of using 3D-printed brain holders to match brain orientation during pathologic sectioning and MRI acquisition enables rapid and precise comparison of small features seen on MRI to their underlying histology. Published by Elsevier B.V.

Diagnostic imaging of the lumbar disc herniation for radiculopathy by 3D-MRI (MR-myelography)

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Taira, Gaku; Imakiire, Atsuhiro; Endo, Kenji [Tokyo Medical Coll. (Japan); Ichimaru, Katuji

2002-02-01

We have developed a new method of three-dimensional MRI (3D-MRI) which enables a stereoscopic view of the spinal cord and both sides of spinal nerve roots in one image. Anatomical study for normal subjects, the S1 angulations and length were significantly smaller than those of others. The S1 DRG was oval and was the largest. In a pathological study the use of 3D-MRI defects the signal changes following damage to the spinal nerve roots or ganglion in lumbar disc herniation. With regard to signal changes in damaged root ganglion, a good correlation between root compression and root inflammation was detected by experiments. We are currently examining the relationship between the damaged root ganglion, pain sensory disturbance. This study showed that the dorsal root ganglion plays an important role in sensory control of radiculopathy on 3D-MRI. (author)

Diagnostic imaging of the lumbar disc herniation for radiculopathy by 3D-MRI (MR-myelography)

International Nuclear Information System (INIS)

Taira, Gaku; Imakiire, Atsuhiro; Endo, Kenji; Ichimaru, Katuji

2002-01-01

We have developed a new method of three-dimensional MRI (3D-MRI) which enables a stereoscopic view of the spinal cord and both sides of spinal nerve roots in one image. Anatomical study for normal subjects, the S1 angulations and length were significantly smaller than those of others. The S1 DRG was oval and was the largest. In a pathological study the use of 3D-MRI defects the signal changes following damage to the spinal nerve roots or ganglion in lumbar disc herniation. With regard to signal changes in damaged root ganglion, a good correlation between root compression and root inflammation was detected by experiments. We are currently examining the relationship between the damaged root ganglion, pain sensory disturbance. This study showed that the dorsal root ganglion plays an important role in sensory control of radiculopathy on 3D-MRI. (author)

A survey on abnormal uterine bleeding among radiographers with frequent MRI exposure using intrauterine contraceptive devices.

Science.gov (United States)

Huss, A; Schaap, K; Kromhout, H

2018-02-01

Based on a previous case report of menometrorrhagia (prolonged/excessive uterine bleeding, occurring at irregular and/or frequent intervals) in MRI workers with intrauterine devices (IUDs), it was evaluated whether this association could be confirmed. A survey was performed among 381 female radiographers registered with their national association. Logistic regression was used to analyze associations of abnormal uterine bleeding with the frequency of working with MRI scanners, presence near the scanner/in the scanner room during image acquisition, and with scanner strength or type. A total of 68 women reported using IUDs, and 72 reported abnormal uterine bleeding. Compared with unexposed women not using IUDs, the odds ratio in women with IUDs working with MRI scanners was 2.09 (95% confidence interval 0.83-3.66). Associations were stronger if women working with MRI reported being present during image acquisition (odds ratio 3.43, 95% CI 1.26-9.34). Associations with scanner strength or type were not consistent. Radiographers using IUDs who are occupationally exposed to stray fields from MRI scanners report abnormal uterine bleeding more often than their co-workers without an IUD, or nonexposed co-workers with an IUD. In particular, radiographers present inside the scanner room during image acquisition showed an increased risk. Magn Reson Med 79:1083-1089, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Prospective comparison of T2w-MRI and dynamic-contrast-enhanced MRI, 3D-MR spectroscopic imaging or diffusion-weighted MRI in repeat TRUS-guided biopsies

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Portalez, Daniel [Clinique Pasteur, 45, Department of Radiology, Toulouse (France); Rollin, Gautier; Mouly, Patrick; Jonca, Frederic; Malavaud, Bernard [Hopital de Rangueil, Department of Urology, Toulouse Cedex 9 (France); Leandri, Pierre [Clinique Saint Jean, 20, Department of Urology, Toulouse (France); Elman, Benjamin [Clinique Pasteur, 45, Department of Urology, Toulouse (France)

2010-12-15

To compare T2-weighted MRI and functional MRI techniques in guiding repeat prostate biopsies. Sixty-eight patients with a history of negative biopsies, negative digital rectal examination and elevated PSA were imaged before repeat biopsies. Dichotomous criteria were used with visual validation of T2-weighted MRI, dynamic contrast-enhanced MRI and literature-derived cut-offs for 3D-spectroscopy MRI (choline-creatine-to-citrate ratio >0.86) and diffusion-weighted imaging (ADC x 10{sup 3} mm{sup 2}/s < 1.24). For each segment and MRI technique, results were rendered as being suspicious/non-suspicious for malignancy. Sextant biopsies, transition zone biopsies and at least two additional biopsies of suspicious areas were taken. In the peripheral zones, 105/408 segments and in the transition zones 19/136 segments were suspicious according to at least one MRI technique. A total of 28/68 (41.2%) patients were found to have cancer. Diffusion-weighted imaging exhibited the highest positive predictive value (0.52) compared with T2-weighted MRI (0.29), dynamic contrast-enhanced MRI (0.33) and 3D-spectroscopy MRI (0.25). Logistic regression showed the probability of cancer in a segment increasing 12-fold when T2-weighted and diffusion-weighted imaging MRI were both suspicious (63.4%) compared with both being non-suspicious (5.2%). The proposed system of analysis and reporting could prove clinically relevant in the decision whether to repeat targeted biopsies. (orig.)

Streamlining the Process of 3D Printing a Brain From a Structural MRI

Directory of Open Access Journals (Sweden)

Daniel Peterson

2017-05-01

Full Text Available Currently, the process of obtaining a 3D model from a structural MRI requires specialized knowlege and skills. This is not due to the fundamental difficulty and complexity of the process, but is a result of the fact that the neccessary tools were developed for and by neuroimaging researchers. This project describes a publically available utility implemented as a Docker image that takes a structural MRI as input, and gives files for 3D printing as output, along with a rendered image of the surface.

Custom Fit 3D-Printed Brain Holders for Comparison of Histology with MRI in Marmosets

Science.gov (United States)

Guy, Joseph R.; Sati, Pascal; Leibovitch, Emily; Jacobson, Steven; Silva, Afonso C.; Reich, Daniel S.

2015-01-01

Background MRI has the advantage of sampling large areas of tissue and locating areas of interest in 3D space in both living and ex vivo systems, whereas histology has the ability to examine thin slices of ex vivo tissue with high detail and specificity. Although both are valuable tools, it is currently difficult to make high-precision comparisons between MRI and histology due to large differences inherent to the techniques. A method combining the advantages would be an asset to understanding the pathological correlates of MRI. New Method 3D-printed brain holders were used to maintain marmoset brains in the same orientation during acquisition of ex vivo MRI and pathologic cutting of the tissue. Results The results of maintaining this same orientation show that sub-millimeter, discrete neuropathological features in marmoset brain consistently share size, shape, and location between histology and ex vivo MRI, which facilitates comparison with serial imaging acquired in vivo. Comparison with Existing Methods Existing methods use computational approaches sensitive to data input in order to warp histologic images to match large-scale features on MRI, but the new method requires no warping of images, due to a preregistration accomplished in the technique, and is insensitive to data formatting and artifacts in both MRI and histology. Conclusions The simple method of using 3D-printed brain holders to match brain orientation during pathologic sectioning and MRI acquisition enables rapid and precise comparison of small features seen on MRI to their underlying histology. PMID:26365332

Non-contrast 3D black blood MRI for abdominal aortic aneurysm surveillance: comparison with CT angiography

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Zhu, Chengcheng; Leach, Joseph R.; Hope, Michael D. [University of California San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Tian, Bing; Liu, Qi; Lu, Jianping; Chen, Luguang [Changhai Hospital, Department of Radiology, Shanghai (China); Saloner, David [University of California San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Radiology Service, VA Medical Center, San Francisco, CA (United States)

2017-05-15

Management of abdominal aortic aneurysms (AAAs) is based on diameter. CT angiography (CTA) is commonly used, but requires radiation and iodinated contrast. Non-contrast MRI is an appealing alternative that may allow better characterization of intraluminal thrombus (ILT). This study aims to 1) validate non-contrast MRI for measuring AAA diameter, and 2) to assess ILT with CTA and MRI. 28 patients with AAAs (diameter 50.7 ± 12.3 mm) underwent CTA and non-contrast MRI. MRI was acquired at 3 T using 1) a conventional 3D gradient echo (GRE) sequence and 2) a 3D T{sub 1}-weighted black blood fast-spin-echo sequence. Two radiologists independently measured the AAA diameter. The ratio of signal of ILT and adjacent psoas muscle (ILT{sub r} = signal{sub ILT}/signal{sub Muscle}) was quantified. Strong agreement between CTA and non-contrast MRI was shown for AAA diameter (intra-class coefficient > 0.99). Both approaches had excellent inter-observer reproducibility (ICC > 0.99). ILT appeared homogenous on CTA, whereas MRI revealed compositional variations. Patients with AAAs ≥5.5 cm and <5.5 cm had a variety of distributions of old/fresh ILT types. Non-contrast 3D black blood MRI provides accurate and reproducible AAA diameter measurements as validated by CTA. It also provides unique information about ILT composition, which may be linked with elevated risk for disease progression. (orig.)

Non-contrast 3D black blood MRI for abdominal aortic aneurysm surveillance: comparison with CT angiography

International Nuclear Information System (INIS)

Zhu, Chengcheng; Leach, Joseph R.; Hope, Michael D.; Tian, Bing; Liu, Qi; Lu, Jianping; Chen, Luguang; Saloner, David

2017-01-01

Management of abdominal aortic aneurysms (AAAs) is based on diameter. CT angiography (CTA) is commonly used, but requires radiation and iodinated contrast. Non-contrast MRI is an appealing alternative that may allow better characterization of intraluminal thrombus (ILT). This study aims to 1) validate non-contrast MRI for measuring AAA diameter, and 2) to assess ILT with CTA and MRI. 28 patients with AAAs (diameter 50.7 ± 12.3 mm) underwent CTA and non-contrast MRI. MRI was acquired at 3 T using 1) a conventional 3D gradient echo (GRE) sequence and 2) a 3D T_1-weighted black blood fast-spin-echo sequence. Two radiologists independently measured the AAA diameter. The ratio of signal of ILT and adjacent psoas muscle (ILT_r = signal_I_L_T/signal_M_u_s_c_l_e) was quantified. Strong agreement between CTA and non-contrast MRI was shown for AAA diameter (intra-class coefficient > 0.99). Both approaches had excellent inter-observer reproducibility (ICC > 0.99). ILT appeared homogenous on CTA, whereas MRI revealed compositional variations. Patients with AAAs ≥5.5 cm and <5.5 cm had a variety of distributions of old/fresh ILT types. Non-contrast 3D black blood MRI provides accurate and reproducible AAA diameter measurements as validated by CTA. It also provides unique information about ILT composition, which may be linked with elevated risk for disease progression. (orig.)

Paediatrics brain imaging in epilepsy: common presenting symptoms and spectrum of abnormalities detected on MRI

International Nuclear Information System (INIS)

Ali, A.; Akram, F.; Khan, G.; Hussain, S.

2017-01-01

Epilepsy, a common neurological disorder can present at any age and has a number of aetiologies with underlying brain disease being the most common aetiology. Brain imaging becomes important and mandatory in the work up for epilepsy in localization and lateralization of the seizure focus. Methods: This cross-sectional study was conducted in the department of Radiology Ayub Medical Teaching Institution Abbottabad from 1st March 2015 to 31st March 2016. A total of 209 children aged 28 days to 14 years were included in the study who presented with seizures to clinicians. Information obtained from history, clinical examination and investigations especially MRI brains were recorded in a prescribed pro forma. The data was analysed in SPSS 20. Results: MRI examination was unremarkable in 44.01% (n=92) and mild generalized brain atrophy was noted in 12.91% (n=27). Arachnoid cysts, mild unilateral brain atrophy and hydrocephalous due to aqueduct stenosis were recorded in 3.82% (n=8) of each group. Neoplastic lesions were the second most common abnormal MRI finding and constituted 5.74% (n=12). Leukodystrophy was diagnosed in 4.78% (n=10). MRI examination showed ring enhancing lesions (tuberculomas) and AVM in 1.43% (n=3) of each group. Perinatal ischemia and intracranial infection, (focal or generalized) were recorded in 2.87% (n=6) of each group. A 0.95 % (n=2) of children in each group had agenesis of corpus callosum and cavernoma. The radiological MRI diagnosis of Raussmussen encephalitis was made in 3.34% (n=7). Single case, each of mesial temporal sclerosis, subdural haemorrhage, infarct and craniopharyngioma was recorded making 0.47 % of the total patients in each case. Conclusion: MRI examination was abnormal in significant number of patients (55.86%), so therefore if properly utilized, in a good clinical context, this can identify most of the structural brain abnormalities in paediatric patients presenting with seizures. (author)

Ciguatera fish poisoning with elevated muscle enzymes and abnormal spinal MRI.

Science.gov (United States)

Wasay, Mohammad; Sarangzai, Amanullah; Siddiqi, Ather; Nizami, Qamaruddin

2008-03-01

We report three cases of ciguatera fish poisoning. One patient died secondary to respiratory failure. Two patients showed elevated muscle enzymes and one patients had an abnormal cervical spinal MRI. MRI findings have not been previously described. MRI findings explain the mechanism of the L'hermitte phenomenon (a common complaint) among these patients. Respiratory failure is rare in ciguatera fish poisoning. Our findings suggest this could be related to respiratory muscles involvement.

Utility of reconstructed image from 3-D MRI in the region of oral cavity

International Nuclear Information System (INIS)

Murakami, Shumei; Kakimoto, Naoya; Nakatani, Atsutoshi; Furuya, Shigeo; Furukawa, Shouhei; Fuchihata, Hajime

1998-01-01

The 3-D MRI with short TR was performed in the region of oral cavity, jaw and face, and utility of the reconstructed image was examined. Subjects were 8 healthy volunteers and 12 patients. The 3-D MRI was performed using SPGR with the following parameters; TR: 8 or 9 msec, TE: 2 or 3 msec, and FA: 20-30 degrees. Imaging direction was vertical to body axis. The matrix number was 256 x 192, slice thickness was 1 mm, slice interval was 0 and slice number was 128. The obtained image was reconstructed using software Reformat''. Detectability of temporomandibular joint disc was not enough in 8 of 20 cases. Detectability of mandibular canal was clear in 18 of 20 cases. In panorama MRI, soft tissue such as submandibular gland was detected. But, in hard tissue such as teeth or maxilla, there was a more little information in panorama MRI than in panorama X-ray photography. (K.H.)

Brain MRI abnormalities in neuromyelitis optica

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Wang Fei, E-mail: feiwang1973@gmail.com [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China); Liu Yaou, E-mail: asiaeurope80@gmail.com [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China); Duan Yunyun, E-mail: duanyun2003@sohu.com [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China); Li Kuncheng, E-mail: kunchengli@yahoo.com.cn [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China); Education Ministry Key Laboratory for Neurodegenerative Disease, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China)

2011-11-15

Objective: The purpose of this study was to explore brain MRI findings in neuromyelitis optica (NMO) and to investigate specific brain lesions with respect to the localization of aquaporin-4 (AQP-4). Materials and methods: Forty admitted patients (36 women) who satisfied the 2006 criteria of Wingerchuk et al. for NMO were included in this study. All patients received a neurological examination and MRI scanning including brain and spinal cord. MRIs were classified as normal, nonspecific, multiple sclerosis-like, typical abnormalities. MS-like lesions were too few to satisfy the Barkhof et al. criteria for MS. Confluent lesions involving high AQP-4 regions were considered typical. Non-enhancing deep white matter lesions other than MS-like lesions or typical lesions were classified as nonspecific. Results: Brain MRI lesions were delineated in 12 patients (25%). Four patients (10%) had hypothalamus, brainstem or periventricle lesions. Six (15%) patients were nonspecific, and 2 (5%) patients had multiple sclerosis-like lesions. Conclusion: Brain MRIs are negative in most NMO, and brain lesions do not exclude the diagnosis of NMO. Hypothalamus, brainstem or periventricle lesions, corresponding to high sites of AQP-4 in the brain, are indicative of lesions of NMO.

Brain MRI abnormalities in neuromyelitis optica

International Nuclear Information System (INIS)

Wang Fei; Liu Yaou; Duan Yunyun; Li Kuncheng

2011-01-01

Objective: The purpose of this study was to explore brain MRI findings in neuromyelitis optica (NMO) and to investigate specific brain lesions with respect to the localization of aquaporin-4 (AQP-4). Materials and methods: Forty admitted patients (36 women) who satisfied the 2006 criteria of Wingerchuk et al. for NMO were included in this study. All patients received a neurological examination and MRI scanning including brain and spinal cord. MRIs were classified as normal, nonspecific, multiple sclerosis-like, typical abnormalities. MS-like lesions were too few to satisfy the Barkhof et al. criteria for MS. Confluent lesions involving high AQP-4 regions were considered typical. Non-enhancing deep white matter lesions other than MS-like lesions or typical lesions were classified as nonspecific. Results: Brain MRI lesions were delineated in 12 patients (25%). Four patients (10%) had hypothalamus, brainstem or periventricle lesions. Six (15%) patients were nonspecific, and 2 (5%) patients had multiple sclerosis-like lesions. Conclusion: Brain MRIs are negative in most NMO, and brain lesions do not exclude the diagnosis of NMO. Hypothalamus, brainstem or periventricle lesions, corresponding to high sites of AQP-4 in the brain, are indicative of lesions of NMO.

Intracranial artery velocity measurement using 4D PC MRI at 3 T: comparison with transcranial ultrasound techniques and 2D PC MRI

International Nuclear Information System (INIS)

Meckel, Stephan; Leitner, Lorenz; Schubert, Tilman; Bonati, Leo H.; Lyrer, Philippe; Santini, Francesco; Stalder, Aurelien F.; Markl, Michael; Wetzel, Stephan G.

2013-01-01

4D phase contrast MR imaging (4D PC MRI) has been introduced for spatiotemporal evaluation of intracranial hemodynamics in various cerebrovascular diseases. However, it still lacks validation with standards of reference. Our goal was to compare blood flow quantification derived from 4D PC MRI with transcranial ultrasound and 2D PC MRI. Velocity measurements within large intracranial arteries [internal carotid artery (ICA), basilar artery (BA), and middle cerebral artery (MCA)] were obtained in 20 young healthy volunteers with 4D and 2D PC MRI, transcranial Doppler sonography (TCD), and transcranial color-coded duplex sonography (TCCD). Maximum velocities at peak systole (PSV) and end diastole (EDV) were compared using regression analysis and Bland-Altman plots. Correlation of 4D PC MRI measured velocities was higher in comparison with TCD (r = 0.49-0.66) than with TCCD (0.35-0.44) and 2D PC MRI (0.52-0.60). In mid-BA and ICA C7 segment, a significant correlation was found with TCD (0.68-0.81 and 0.65-0.71, respectively). No significant correlation was found in carotid siphon. On average over all volunteers, PSVs and EDVs in MCA were minimally underestimated compared with TCD/TCCD. Minimal overestimation of velocities was found compared to TCD in mid-BA and ICA C7 segment. 4D PC MRI appears as valid alternative for intracranial velocity measurement consistent with previous reference standards, foremost with TCD. Spatiotemporal averaging effects might contribute to vessel size-dependent mild underestimation of velocities in smaller (MCA), and overestimation in larger-sized (BA and ICA) arteries, respectively. Complete spatiotemporal flow analysis may be advantageous in anatomically complex regions (e.g. carotid siphon) relative to restrictions of ultrasound techniques. (orig.)

High-resolution MRI of the labyrinth. Optimization of scan parameters with 3D-FSE

International Nuclear Information System (INIS)

Sakata, Motomichi; Harada, Kuniaki; Shirase, Ryuji; Kumagai, Akiko; Ogasawara, Masashi

2005-01-01

The aim of our study was to optimize the parameters of high-resolution MRI of the labyrinth with a 3D fast spin-echo (3D-FSE) sequence. We investigated repetition time (TR), echo time (TE), Matrix, field of view (FOV), and coil selection in terms of CNR (contrast-to-noise ratio) and SNR (signal-to-noise ratio) by comparing axial images and/or three-dimensional images. The optimal 3D-FSE sequence parameters were as follows: 1.5 Tesla MR unit (Signa LX, GE Medical Systems), 3D-FSE sequence, dual 3-inch surface coil, acquisition time=12.08 min, TR=5000 msec, TE=300 msec, 3 number of excitations (NEX), FOV=12 cm, matrix=256 x 256, slice thickness=0.5 mm/0.0 sp, echo train=64, bandwidth=±31.5 kHz. High-resolution MRI of the labyrinth using the optimized 3D-FSE sequence parameters permits visualization of important anatomic details (such as scala tympani and scala vestibuli), making it possible to determine inner ear anomalies and the patency of cochlear turns. To obtain excellent heavily T2-weighted axial and three-dimensional images in the labyrinth, high CNR, SNR, and spatial resolution are significant factors at the present time. Furthermore, it is important not only to optimize the scan parameters of 3D-FSE but also to select an appropriate coil for high-resolution MRI of the labyrinth. (author)

Creation of computerized 3D MRI-integrated atlases of the human basal ganglia and thalamus

Directory of Open Access Journals (Sweden)

Abbas F. Sadikot

2011-09-01

Full Text Available Functional brain imaging and neurosurgery in subcortical areas often requires visualization of brain nuclei beyond the resolution of current Magnetic Resonance Imaging (MRI methods. We present techniques used to create: 1 a lower resolution 3D atlas, based on the Schaltenbrand and Wahren print atlas, which was integrated into a stereotactic neurosurgery planning and visualization platform (VIPER; and 2 a higher resolution 3D atlas derived from a single set of manually segmented histological slices containing nuclei of the basal ganglia, thalamus, basal forebrain and medial temporal lobe. Both atlases were integrated to a canonical MRI (Colin27 from a young male participant by manually identifying homologous landmarks. The lower resolution atlas was then warped to fit the MRI based on the identified landmarks. A pseudo-MRI representation of the high-resolution atlas was created, and a nonlinear transformation was calculated in order to match the atlas to the template MRI. The atlas can then be warped to match the anatomy of Parkinson’s disease surgical candidates by using 3D automated nonlinear deformation methods. By way of functional validation of the atlas, the location of the sensory thalamus was correlated with stereotactic intraoperative physiological data. The position of subthalamic electrode positions in patients with Parkinson’s disease was also evaluated in the atlas-integrated MRI space. Finally, probabilistic maps of subthalamic stimulation electrodes were developed, in order to allow group analysis of the location of contacts associated with the best motor outcomes. We have therefore developed, and are continuing to validate, a high-resolution computerized MRI-integrated 3D histological atlas, which is useful in functional neurosurgery, and for functional and anatomical studies of the human basal ganglia, thalamus and basal forebrain.

Cerebral perfusion abnormalities in therapy-resistant epilepsy in childhood: comparison between EEG, MRI and 99Tcm-ECD brain SPET.

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Vattimo, A; Burroni, L; Bertelli, P; Volterrani, D; Vella, A

1996-01-01

We performed 99Tcm-ethyl cysteinate dimer (ECD) interictal single photon emission tomography (SPET) in 26 children with severe therapy-resistant epilepsy. All the children underwent a detailed clinical examination, an electroencephalogram (EEG) investigation and brain magnetic resonance imaging (MRI). In 21 of the 26 children, SPET demonstrated brain blood flow abnormalities, in 13 cases in the same territories that showed EEG alterations. MRI showed structural lesions in 6 of the 26 children, while SPET imaging confirmed these abnormalities in only 5 children. The lesion not detected on SPET was shown to be 3 mm thick on MRI. Five symptomatic patients had normal SPET. In one of these patients, the EEG findings were normal and MRI revealed a small calcific nodule (4 mm thick); in the others, the EEG showed non-focal but diffuse abnormalities. These data confirm that brain SPET is sensitive in detecting and localizing hypoperfused areas that could be associated with epileptic foci in this group of patients, even when the MRI image is normal.

3D Registration of mpMRI for Assessment of Prostate Cancer Focal Therapy.

Science.gov (United States)

Orczyk, Clément; Rosenkrantz, Andrew B; Mikheev, Artem; Villers, Arnauld; Bernaudin, Myriam; Taneja, Samir S; Valable, Samuel; Rusinek, Henry

2017-12-01

This study aimed to assess a novel method of three-dimensional (3D) co-registration of prostate magnetic resonance imaging (MRI) examinations performed before and after prostate cancer focal therapy. We developed a software platform for automatic 3D deformable co-registration of prostate MRI at different time points and applied this method to 10 patients who underwent focal ablative therapy. MRI examinations were performed preoperatively, as well as 1 week and 6 months post treatment. Rigid registration served as reference for assessing co-registration accuracy and precision. Segmentation of preoperative and postoperative prostate revealed a significant postoperative volume decrease of the gland that averaged 6.49 cc (P = .017). Applying deformable transformation based on mutual information from 120 pairs of MRI slices, we refined by 2.9 mm (max. 6.25 mm) the alignment of the ablation zone, segmented from contrast-enhanced images on the 1-week postoperative examination, to the 6-month postoperative T2-weighted images. This represented a 500% improvement over the rigid approach (P = .001), corrected by volume. The dissimilarity by Dice index of the mapped ablation zone using deformable transformation vs rigid control was significantly (P = .04) higher at the ablation site than in the whole gland. Our findings illustrate our method's ability to correct for deformation at the ablation site. The preliminary analysis suggests that deformable transformation computed from mutual information of preoperative and follow-up MRI is accurate in co-registration of MRI examinations performed before and after focal therapy. The ability to localize the previously ablated tissue in 3D space may improve targeting for image-guided follow-up biopsy within focal therapy protocols. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Quantitative analysis of pulmonary perfusion using time-resolved parallel 3D MRI - initial results

International Nuclear Information System (INIS)

Fink, C.; Buhmann, R.; Plathow, C.; Puderbach, M.; Kauczor, H.U.; Risse, F.; Ley, S.; Meyer, F.J.

2004-01-01

Purpose: to assess the use of time-resolved parallel 3D MRI for a quantitative analysis of pulmonary perfusion in patients with cardiopulmonary disease. Materials and methods: eight patients with pulmonary embolism or pulmonary hypertension were examined with a time-resolved 3D gradient echo pulse sequence with parallel imaging techniques (FLASH 3D, TE/TR: 0.8/1.9 ms; flip angle: 40 ; GRAPPA). A quantitative perfusion analysis based on indicator dilution theory was performed using a dedicated software. Results: patients with pulmonary embolism or chronic thromboembolic pulmonary hypertension revealed characteristic wedge-shaped perfusion defects at perfusion MRI. They were characterized by a decreased pulmonary blood flow (PBF) and pulmonary blood volume (PBV) and increased mean transit time (MTT). Patients with primary pulmonary hypertension or eisenmenger syndrome showed a more homogeneous perfusion pattern. The mean MTT of all patients was 3.3 - 4.7 s. The mean PBF and PBV showed a broader interindividual variation (PBF: 104-322 ml/100 ml/min; PBV: 8 - 21 ml/100 ml). Conclusion: time-resolved parallel 3D MRI allows at least a semi-quantitative assessment of lung perfusion. Future studies will have to assess the clinical value of this quantitative information for the diagnosis and management of cardiopulmonary disease. (orig.) [de

Whole-brain vascular reactivity measured by fMRI using hyperventilation and breath-holding tasks: efficacy of 3D prospective acquisition correction (3D-PACE) for head motion

International Nuclear Information System (INIS)

Naganawa, Shinji; Koshikawa, Tokiko; Fukatsu, Hiroshi; Ishigaki, Takeo; Maruyama, Katsuya; Takizawa, Osamu

2004-01-01

Functional MR imaging (fMRI) study using hyperventilation and breath-holding task has been reported to be one of the non-invasive methods to examine whole-brain vascular reactivity. The purpose of this study was to evaluate the efficacy of a method for 3D prospective detection and correction of head motion (3D-PACE) in a study of whole-brain vascular reactivity using hyperventilation and breath-holding tasks. Eight healthy volunteers were scanned using an fMRI protocol of hyperventilation and breath-holding task blocks at 3 T in separate runs with and without 3D-PACE. In two subjects, two more runs with and without 3D-PACE were repeated. The mean total number of activated voxels ± standard deviation was 26,405.3±1,822.2 in the run with 3D-PACE and 17,329.9±2,766.3 in the run without 3D-PACE (P<0.05), although there is some intersubject variation regarding the effect of 3D-PACE. In the two subjects whose performed two more runs, the number of activated voxels were smaller in the run without 3D-PACE than even in the run with 3D-PACE performed later. We conclude that 3D-PACE is beneficial for fMRI studies of whole-brain vascular reactivity induced by hyperventilation and breath-holding. (orig.)

Temporal pole abnormalities detected by 3 T MRI in temporal lobe epilepsy due to hippocampal sclerosis: No influence on seizure outcome after surgery.

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Casciato, Sara; Picardi, Angelo; D'Aniello, Alfredo; De Risi, Marco; Grillea, Giovanni; Quarato, Pier Paolo; Mascia, Addolorata; Grammaldo, Liliana G; Meldolesi, Giulio Nicolo'; Morace, Roberta; Esposito, Vincenzo; Di Gennaro, Giancarlo

2017-05-01

To assess the clinical significance of temporal pole abnormalities (temporopolar blurring, TB, and temporopolar atrophy, TA) detected by using 3 Tesla MRI in the preoperative workup in patients with temporal lobe epilepsy due to hippocampal sclerosis (TLE-HS) who underwent surgery. We studied 78 consecutive patients with TLE-HS who underwent surgery and were followed up for at least 2 years. Based on findings of pre-surgical 3 Tesla MRI, patients were subdivided in subgroups according to the presence of TB or TA. Subgroups were compared on demographic, clinical, neuropsychological data and seizure outcome. TB was found in 39 (50%) patients, while TA was found in 32 (41%) patients, always ipsilateral to HS, with a considerable degree of overlap (69%) between TB and TA (p=0.01). Patients with temporopolar abnormalities did not significantly differ from those without TB or TA with regard to sex, age, age of epilepsy onset, duration of epilepsy, history of febrile convulsions or birth complications, side of surgery, seizure frequency at surgery, presence of GTCSs, and, in particular, seizure outcome. On the other hand, TB patients show a less frequent family history of epilepsy (pepilepsy onset showed a trend to be lower in the TB group (p=.09). Patients with temporopolar atrophy did not significantly differ from those without TA on any variable, except for age at epilepsy onset, which was significantly lower for the TA group (pepilepsy also showed a trend to be associated with TA (p=.08). Multivariate analysis corroborated the association between temporopolar abnormalities and absence of family history of epilepsy and history of birth complications. High-field 3 T MRI in the preoperative workup for epilepsy surgery confirms that temporopolar abnormalities are frequent findings in TLE-HS patients and may be helpful to lateralize the epileptogenic zone. Their presence did not influence seizure outcome. Copyright © 2017 British Epilepsy Association. Published by

Registration of 3D ultrasound computer tomography and MRI for evaluation of tissue correspondences

Science.gov (United States)

Hopp, T.; Dapp, R.; Zapf, M.; Kretzek, E.; Gemmeke, H.; Ruiter, N. V.

2015-03-01

3D Ultrasound Computer Tomography (USCT) is a new imaging method for breast cancer diagnosis. In the current state of development it is essential to correlate USCT with a known imaging modality like MRI to evaluate how different tissue types are depicted. Due to different imaging conditions, e.g. with the breast subject to buoyancy in USCT, a direct correlation is demanding. We present a 3D image registration method to reduce positioning differences and allow direct side-by-side comparison of USCT and MRI volumes. It is based on a two-step approach including a buoyancy simulation with a biomechanical model and free form deformations using cubic B-Splines for a surface refinement. Simulation parameters are optimized patient-specifically in a simulated annealing scheme. The method was evaluated with in-vivo datasets resulting in an average registration error below 5mm. Correlating tissue structures can thereby be located in the same or nearby slices in both modalities and three-dimensional non-linear deformations due to the buoyancy are reduced. Image fusion of MRI volumes and USCT sound speed volumes was performed for intuitive display. By applying the registration to data of our first in-vivo study with the KIT 3D USCT, we could correlate several tissue structures in MRI and USCT images and learn how connective tissue, carcinomas and breast implants observed in the MRI are depicted in the USCT imaging modes.

Automatic extraction of soft tissues from 3D MRI head images using model driven analysis

International Nuclear Information System (INIS)

Jiang, Hao; Yamamoto, Shinji; Imao, Masanao.

1995-01-01

This paper presents an automatic extraction system (called TOPS-3D : Top Down Parallel Pattern Recognition System for 3D Images) of soft tissues from 3D MRI head images by using model driven analysis algorithm. As the construction of system TOPS we developed, two concepts have been considered in the design of system TOPS-3D. One is the system having a hierarchical structure of reasoning using model information in higher level, and the other is a parallel image processing structure used to extract plural candidate regions for a destination entity. The new points of system TOPS-3D are as follows. (1) The TOPS-3D is a three-dimensional image analysis system including 3D model construction and 3D image processing techniques. (2) A technique is proposed to increase connectivity between knowledge processing in higher level and image processing in lower level. The technique is realized by applying opening operation of mathematical morphology, in which a structural model function defined in higher level by knowledge representation is immediately used to the filter function of opening operation as image processing in lower level. The system TOPS-3D applied to 3D MRI head images consists of three levels. First and second levels are reasoning part, and third level is image processing part. In experiments, we applied 5 samples of 3D MRI head images with size 128 x 128 x 128 pixels to the system TOPS-3D to extract the regions of soft tissues such as cerebrum, cerebellum and brain stem. From the experimental results, the system is robust for variation of input data by using model information, and the position and shape of soft tissues are extracted corresponding to anatomical structure. (author)

Interest of the steady state free precession (SSFP) sequence for 3D modeling of the whole fetus.

Science.gov (United States)

Anquez, J; Angelini, E; Bloch, I; Merzoug, V; Bellaiche-Millischer, A E; Adamsbaum, C

2007-01-01

Fetal magnetic resonance imaging (MRI) has been gaining interest over the last two decades. Current fast MRI sequences provide imaging data of the whole uterus in less than 20 seconds, avoiding fetal motion related artifacts without any maternal or fetal sedation. MRI has proved to be a useful adjunct to echographic screening for prenatal diagnosis. However, MRI volumetric data is still mainly interpreted on 2D slices and 3D applications remain limited. In this paper, we discuss the qualities of the SSFP MRI sequences to provide adequate data for 3D segmentation and modeling of the fetus. Potential exploitations of 3D segmentation and derived anatomical models cover several domains: biometric and morphologic clinical studies, quantitative longitudinal studies of normal and abnormal fetus developments, direct visualization of the overall fetus body and simulations in different fields (surgery, radiation dosimetry,...).

Reversible MRI abnormalities in an unusual paediatric presentation of Wernicke's encephalopathy

International Nuclear Information System (INIS)

Sparacia, G.; Banco, A.; Lagalla, R.

1999-01-01

Background. We report an unusual paediatric presentation of acute Wernicke's encephalopathy in a 12-year-old boy affected by chronic gastrointestinal disease. MRI demonstrated, in addition to the typical diencephalic and mesencephalic signal abnormalities on T2-weighted images, enhancement of the mammillary bodies and the floor of the hypothalamus. Materials and methods. Following parenteral administration of thiamine for 4 days, the patient recovered from his neurological deficits and on follow-up enhanced MRI 1 month later, no signal abnormalities were found nor was there diencephalic or mesencephalic atrophy, as is usual in the chronic phase of the disease. Results. MRI provides crucial information in the diagnosis of Wernicke's encephalopathy, either in the acute or chronic phases of the disease. Conclusion. Our report provides an additional clue for recognition of the acute phase of the disease; enhancement of the floor of the hypothalamus has not previously been described despite its recorded involvement at autopsy. (orig.)

Morphostructural MRI Abnormalities Related to Neuropsychiatric Disorders Associated to Multiple Sclerosis

Directory of Open Access Journals (Sweden)

Simona Bonavita

2013-01-01

Full Text Available Multiple Sclerosis associated neuropsychiatric disorders include major depression (MD, obsessive-compulsive disorder (OCD, bipolar affective disorder, euphoria, pseudobulbar affect, psychosis, and personality change. Magnetic Resonance Imaging (MRI studies focused mainly on identifying morphostructural correlates of MD; only a few anecdotal cases on OCD associated to MS (OCD-MS, euphoria, pseudobulbar affect, psychosis, personality change, and one research article on MRI abnormalities in OCD-MS have been published. Therefore, in the present review we will report mainly on neuroimaging abnormalities found in MS patients with MD and OCD. All together, the studies on MD associated to MS suggest that, in this disease, depression is linked to a damage involving mainly frontotemporal regions either with discrete lesions (with those visible in T1 weighted images playing a more significant role or subtle normal appearing white matter abnormalities. Hippocampal atrophy, as well, seems to be involved in MS related depression. It is conceivable that grey matter pathology (i.e., global and regional atrophy, cortical lesions, which occurs early in the course of disease, may involve several areas including the dorsolateral prefrontal cortex, the orbitofrontal cortex, and the anterior cingulate cortex whose disruption is currently thought to explain late-life depression. Further MRI studies are necessary to better elucidate OCD pathogenesis in MS.

Hippocampal malrotation: MRI findings

International Nuclear Information System (INIS)

Yanez, Paulina; Martinez, Adriana; Romero, Carlos; Lopez, Miriam; Zaffaroni, Alejandra; Lopez, Adriana

2001-01-01

Purpose: To demonstrate the common features of hippocampus malrotation in patients with epilepsy by volumetric and high-resolution MRI. Material and methods: MRI study was performed in 5 patients (2 females and 3 males) ages ranged between 6-41 years (average: 25 years), all of them with epilepsy diagnosis. MRI was performed with a 1.5 T (GE Signa). The epilepsy protocol include sagittal T1, axial T1 and T2, coronal FLAIR, coronal T2 (high-resolution) and volumetric 3D SPGR IR 1.5 mm thick sequences. Results: The common features found in all patients were: a) Incomplete inversion and round configuration of the hippocampus; b) Unilateral affectation; c) Variable affectation of the hippocampus; d) Normal signal intensity; e) Modification of the inner structure of the hippocampus; f) Abnormal angularity of the collateral sulcus; g) Abnormal position and size of the fornix; h) Normal size of the temporal lobe; and i) Enlargement of the temporal horn with particular configuration. Conclusion: Hippocampus malrotation is a malformation that should be included in the differential diagnosis of the epilepsy patients. MRI provides accurate information for the diagnosis. (author)

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

Science.gov (United States)

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

2018-01-01

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

Computerized liver volumetry on MRI by using 3D geodesic active contour segmentation.

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Huynh, Hieu Trung; Karademir, Ibrahim; Oto, Aytekin; Suzuki, Kenji

2014-01-01

Our purpose was to develop an accurate automated 3D liver segmentation scheme for measuring liver volumes on MRI. Our scheme for MRI liver volumetry consisted of three main stages. First, the preprocessing stage was applied to T1-weighted MRI of the liver in the portal venous phase to reduce noise and produce the boundary-enhanced image. This boundary-enhanced image was used as a speed function for a 3D fast-marching algorithm to generate an initial surface that roughly approximated the shape of the liver. A 3D geodesic-active-contour segmentation algorithm refined the initial surface to precisely determine the liver boundaries. The liver volumes determined by our scheme were compared with those manually traced by a radiologist, used as the reference standard. The two volumetric methods reached excellent agreement (intraclass correlation coefficient, 0.98) without statistical significance (p = 0.42). The average (± SD) accuracy was 99.4% ± 0.14%, and the average Dice overlap coefficient was 93.6% ± 1.7%. The mean processing time for our automated scheme was 1.03 ± 0.13 minutes, whereas that for manual volumetry was 24.0 ± 4.4 minutes (p volumetry based on our automated scheme agreed excellently with reference-standard volumetry, and it required substantially less completion time.

3D gadolinium-enhanced MRI venography: Evaluation of central chest veins and impact on patient management

International Nuclear Information System (INIS)

Oxtoby, J.W.; Widjaja, E.; Gibson, K.M.; Uzoka, K.

2001-01-01

AIM: To assess the value of a simplified 3D gadolinium-enhanced magnetic resonance imaging (MRI) venography for central chest veins. MATERIALS AND METHODS: In this retrospective study of 24 patients, the MRI findings and medical records were reviewed to determine whether MRI results correlated with subsequent findings, and to determine the effect on clinical management. 3D steady state gradient-echo sequence, fast imaging with steady state precession (FISP), was used. We employed a simplified protocol not requiring bolus timing or subtraction to achieve rapid data acquisition and hence good compliance in this group of frail patients. Following intravenous administration of a bolus of gadolinium, two acquisitions were obtained in order to ensure adequate opacification of all veins. Individual partitions and maximum intensity projections were then analysed to determine whether the veins were patent, stenosed or occluded. RESULTS: The indications for MRI were to assess the patency of central veins for the purpose of cannulation or arteriovenous fistula formation in 17 patients. Out of the 12 patients who proceeded to an intervention, MRI venography successfully predicted an appropriate site in 10 patients. In the remaining seven patients, MRI venography was valuable in confirming or excluding the clinical suspicion of central venous thrombosis and directly influenced the management in five patients. CONCLUSION: 3D gadolinium-enhanced MRI venography is a valuable means of providing a global representation of the central venous system and guiding subsequent central venous cannulation. Oxtoby, J.W. et al. (2001)

3D MRI of the colon: methods and first results of 5 patients

International Nuclear Information System (INIS)

Luboldt, W.; Bauerfeind, P.; Pelkonen, P.; Steiner, P.; Krestin, G.P.; Debatin, J.F.

1997-01-01

Purpose: 'Exoscopic' and endoscopic identification of colorectal pathologies via MRI. Methods: 5 patients (36-88 years), two normal and three with different colorectal pathologies (diverticular disease, polyps and carcinoma of the colon), were examined by MRI after colonoscopy. Subsequent to filling of the colon with a gadolinium-water mixture under MRI-monitoring, 3D-data sets of the colon were acquired in prone and supine positions over a 28 sec breathold interval. Subsequently multiplanar T 1 -weighted 2D-sequences were acquired before and following i.v. administration of Gd-DTPA (0.1 mmol/kg BW). All imaging was performed in the coronal orientation. The 3D-data were interactively analysed based on various displays: Maximum intensity projection (MIP), surface shadowed display (SSD), multiplanar reconstruction (MPR), virtual colonoscopy (VC). Results: All of the colorectal pathologies could be interactively diagnosed by MPR. On MIP images some pathologies were missed. VC presented the morphology of colon haustra as well as of all endoluminally growing lesions in a manner similar to endoscopy. The colon masses showed uptake of contrast media and could thus be differentiated from air or faeces. (orig./AJ) [de

Neurovascular coupling to D2/D3 dopamine receptor occupancy using simultaneous PET/functional MRI

DEFF Research Database (Denmark)

Sander, Christin Y; Hooker, Jacob M; Catana, Ciprian

2013-01-01

This study employed simultaneous neuroimaging with positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) to demonstrate the relationship between changes in receptor occupancy measured by PET and changes in brain activity inferred by fMRI. By administering the D2/D3...... dopamine receptor antagonist [(11)C]raclopride at varying specific activities to anesthetized nonhuman primates, we mapped associations between changes in receptor occupancy and hemodynamics [cerebral blood volume (CBV)] in the domains of space, time, and dose. Mass doses of raclopride above tracer levels...... caused increases in CBV and reductions in binding potential that were localized to the dopamine-rich striatum. Moreover, similar temporal profiles were observed for specific binding estimates and changes in CBV. Injection of graded raclopride mass doses revealed a monotonic coupling between neurovascular...

Flow MRI simulation in complex 3D geometries: Application to the cerebral venous network.

Science.gov (United States)

Fortin, Alexandre; Salmon, Stéphanie; Baruthio, Joseph; Delbany, Maya; Durand, Emmanuel

2018-02-05

Develop and evaluate a complete tool to include 3D fluid flows in MRI simulation, leveraging from existing software. Simulation of MR spin flow motion is of high interest in the study of flow artifacts and angiography. However, at present, only a few simulators include this option and most are restricted to static tissue imaging. An extension of JEMRIS, one of the most advanced high performance open-source simulation platforms to date, was developed. The implementation of a Lagrangian description of the flow allows simulating any MR experiment, including both static tissues and complex flow data from computational fluid dynamics. Simulations of simple flow models are compared with real experiments on a physical flow phantom. A realistic simulation of 3D flow MRI on the cerebral venous network is also carried out. Simulations and real experiments are in good agreement. The generality of the framework is illustrated in 2D and 3D with some common flow artifacts (misregistration and inflow enhancement) and with the three main angiographic techniques: phase contrast velocimetry (PC), time-of-flight, and contrast-enhanced imaging MRA. The framework provides a versatile and reusable tool for the simulation of any MRI experiment including physiological fluids and arbitrarily complex flow motion. © 2018 International Society for Magnetic Resonance in Medicine.

Imaging Agonist-Induced D2/D3 Receptor Desensitization and Internalization In Vivo with PET/fMRI.

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Sander, Christin Y; Hooker, Jacob M; Catana, Ciprian; Rosen, Bruce R; Mandeville, Joseph B

2016-04-01

This study investigated the dynamics of dopamine receptor desensitization and internalization, thereby proposing a new technique for non-invasive, in vivo measurements of receptor adaptations. The D2/D3 agonist quinpirole, which induces receptor internalization in vitro, was administered at graded doses in non-human primates while imaging with simultaneous positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). A pronounced temporal divergence between receptor occupancy and fMRI signal was observed: occupancy remained elevated while fMRI responded transiently. Analogous experiments with an antagonist (prochlorperazine) and a lower-affinity agonist (ropinirole) exhibited reduced temporal dissociation between occupancy and function, consistent with a mechanism of desensitization and internalization that depends upon drug efficacy and affinity. We postulated a model that incorporates internalization into a neurovascular-coupling relationship. This model yielded in vivo desensitization/internalization rates (0.2/min for quinpirole) consistent with published in vitro measurements. Overall, these results suggest that simultaneous PET/fMRI enables characterization of dynamic neuroreceptor adaptations in vivo, and may offer a first non-invasive method for assessing receptor desensitization and internalization.

Automatic segmentation of MRI head images by 3-D region growing method which utilizes edge information

International Nuclear Information System (INIS)

Jiang, Hao; Suzuki, Hidetomo; Toriwaki, Jun-ichiro

1991-01-01

This paper presents a 3-D segmentation method that automatically extracts soft tissue from multi-sliced MRI head images. MRI produces a sequence of two-dimensional (2-D) images which contains three-dimensional (3-D) information of organs. To utilize such information we need effective algorithms to treat 3-D digital images and to extract organs and tissues of interest. We developed a method to extract the brain from MRI images which uses a region growing procedure and integrates information of uniformity of gray levels and information of the presence of edge segments in the local area around the pixel of interest. First we generate a kernel region which is a part of brain tissue by simple thresholding. Then we grow the region by means of a region growing algorithm under the control of 3-D edge existence to obtain the region of the brain. Our method is rather simple because it uses basic 3-D image processing techniques like spatial difference. It is robust for variation of gray levels inside a tissue since it also refers to the edge information in the process of region growing. Therefore, the method is flexible enough to be applicable to the segmentation of other images including soft tissues which have complicated shapes and fluctuation in gray levels. (author)

Highly-accelerated self-gated free-breathing 3D cardiac cine MRI: validation in assessment of left ventricular function.

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Liu, Jing; Feng, Li; Shen, Hsin-Wei; Zhu, Chengcheng; Wang, Yan; Mukai, Kanae; Brooks, Gabriel C; Ordovas, Karen; Saloner, David

2017-08-01

This work presents a highly-accelerated, self-gated, free-breathing 3D cardiac cine MRI method for cardiac function assessment. A golden-ratio profile based variable-density, pseudo-random, Cartesian undersampling scheme was implemented for continuous 3D data acquisition. Respiratory self-gating was achieved by deriving motion signal from the acquired MRI data. A multi-coil compressed sensing technique was employed to reconstruct 4D images (3D+time). 3D cardiac cine imaging with self-gating was compared to bellows gating and the clinical standard breath-held 2D cine imaging for evaluation of self-gating accuracy, image quality, and cardiac function in eight volunteers. Reproducibility of 3D imaging was assessed. Self-gated 3D imaging provided an image quality score of 3.4 ± 0.7 vs 4.0 ± 0 with the 2D method (p = 0.06). It determined left ventricular end-systolic volume as 42.4 ± 11.5 mL, end-diastolic volume as 111.1 ± 24.7 mL, and ejection fraction as 62.0 ± 3.1%, which were comparable to the 2D method, with bias ± 1.96 × SD of -0.8 ± 7.5 mL (p = 0.90), 2.6 ± 3.3 mL (p = 0.84) and 1.4 ± 6.4% (p = 0.45), respectively. The proposed 3D cardiac cine imaging method enables reliable respiratory self-gating performance with good reproducibility, and provides comparable image quality and functional measurements to 2D imaging, suggesting that self-gated, free-breathing 3D cardiac cine MRI framework is promising for improved patient comfort and cardiac MRI scan efficiency.

An accurate segmentation method for volumetry of brain tumor in 3D MRI

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Wang, Jiahui; Li, Qiang; Hirai, Toshinori; Katsuragawa, Shigehiko; Li, Feng; Doi, Kunio

2008-03-01

Accurate volumetry of brain tumors in magnetic resonance imaging (MRI) is important for evaluating the interval changes in tumor volumes during and after treatment, and also for planning of radiation therapy. In this study, an automated volumetry method for brain tumors in MRI was developed by use of a new three-dimensional (3-D) image segmentation technique. First, the central location of a tumor was identified by a radiologist, and then a volume of interest (VOI) was determined automatically. To substantially simplify tumor segmentation, we transformed the 3-D image of the tumor into a two-dimensional (2-D) image by use of a "spiral-scanning" technique, in which a radial line originating from the center of the tumor scanned the 3-D image spirally from the "north pole" to the "south pole". The voxels scanned by the radial line provided a transformed 2-D image. We employed dynamic programming to delineate an "optimal" outline of the tumor in the transformed 2-D image. We then transformed the optimal outline back into 3-D image space to determine the volume of the tumor. The volumetry method was trained and evaluated by use of 16 cases with 35 brain tumors. The agreement between tumor volumes provided by computer and a radiologist was employed as a performance metric. Our method provided relatively accurate results with a mean agreement value of 88%.

Detection of infarct lesions from single MRI modality using inconsistency between voxel intensity and spatial location--a 3-D automatic approach.

Science.gov (United States)

Shen, Shan; Szameitat, André J; Sterr, Annette

2008-07-01

Detection of infarct lesions using traditional segmentation methods is always problematic due to intensity similarity between lesions and normal tissues, so that multispectral MRI modalities were often employed for this purpose. However, the high costs of MRI scan and the severity of patient conditions restrict the collection of multiple images. Therefore, in this paper, a new 3-D automatic lesion detection approach was proposed, which required only a single type of anatomical MRI scan. It was developed on a theory that, when lesions were present, the voxel-intensity-based segmentation and the spatial-location-based tissue distribution should be inconsistent in the regions of lesions. The degree of this inconsistency was calculated, which indicated the likelihood of tissue abnormality. Lesions were identified when the inconsistency exceeded a defined threshold. In this approach, the intensity-based segmentation was implemented by the conventional fuzzy c-mean (FCM) algorithm, while the spatial location of tissues was provided by prior tissue probability maps. The use of simulated MRI lesions allowed us to quantitatively evaluate the performance of the proposed method, as the size and location of lesions were prespecified. The results showed that our method effectively detected lesions with 40-80% signal reduction compared to normal tissues (similarity index > 0.7). The capability of the proposed method in practice was also demonstrated on real infarct lesions from 15 stroke patients, where the lesions detected were in broad agreement with true lesions. Furthermore, a comparison to a statistical segmentation approach presented in the literature suggested that our 3-D lesion detection approach was more reliable. Future work will focus on adapting the current method to multiple sclerosis lesion detection.

3D 23Na MRI of human skeletal muscle at 7 Tesla: initial experience

International Nuclear Information System (INIS)

Chang, Gregory; Wang, Ligong; Regatte, Ravinder R.; Schweitzer, Mark E.

2010-01-01

To evaluate healthy skeletal muscle pre- and post-exercise via 7 T 23 Na MRI and muscle proton T 2 mapping, and to evaluate diabetic muscle pre- and post-exercise via 7 T 23 Na MRI. The calves of seven healthy subjects underwent imaging pre- and post-exercise via 7 T 23 Na MRI (3D fast low angle shot, TR/TE = 80 ms/0.160 ms, 4 mm x 4 mm x 4 mm) and 1 week later by 1 H MRI (multiple spin-echo sequence, TR/TE = 3,000 ms/15-90 ms). Four type 2 diabetics also participated in the 23 Na MRI protocol. Pre- and post-exercise sodium signal intensity (SI) and proton T 2 relaxation values were measured/calculated for soleus (S), gastrocnemius (G), and a control, tibialis anterior (TA). Two-tailed t tests were performed. In S/G in healthy subjects post-exercise, sodium SI increased 8-13% (p 1/2 = 22 min), and 1 H T 2 values increased 12-17% (p 1/2 = 12-15 min). In TA, no significant changes in sodium SI or 1 H T 2 values were seen (-2.4 to 1%, p > 0.17). In S/G in diabetics, sodium SI increased 10-11% (p 1/2 = 27-37 min) without significant change in the TA SI (-3.6%, p = 0.066). It is feasible to evaluate skeletal muscle via 3D 23 Na MRI at 7 T. Post-exercise muscle 1 H T 2 values return to baseline more rapidly than sodium SI. Diabetics may demonstrate delayed muscle sodium SI recovery compared with healthy subjects. (orig.)

Iron accumulation in deep cortical layers accounts for MRI signal abnormalities in ALS: correlating 7 tesla MRI and pathology.

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Justin Y Kwan

Full Text Available Amyotrophic lateral sclerosis (ALS is a progressive neurodegenerative disorder characterized by cortical and spinal motor neuron dysfunction. Routine magnetic resonance imaging (MRI studies have previously shown hypointense signal in the motor cortex on T(2-weighted images in some ALS patients, however, the cause of this finding is unknown. To investigate the utility of this MR signal change as a marker of cortical motor neuron degeneration, signal abnormalities on 3T and 7T MR images of the brain were compared, and pathology was obtained in two ALS patients to determine the origin of the motor cortex hypointensity. Nineteen patients with clinically probable or definite ALS by El Escorial criteria and 19 healthy controls underwent 3T MRI. A 7T MRI scan was carried out on five ALS patients who had motor cortex hypointensity on the 3T FLAIR sequence and on three healthy controls. Postmortem 7T MRI of the brain was performed in one ALS patient and histological studies of the brains and spinal cords were obtained post-mortem in two patients. The motor cortex hypointensity on 3T FLAIR images was present in greater frequency in ALS patients. Increased hypointensity correlated with greater severity of upper motor neuron impairment. Analysis of 7T T(2(*-weighted gradient echo imaging localized the signal alteration to the deeper layers of the motor cortex in both ALS patients. Pathological studies showed increased iron accumulation in microglial cells in areas corresponding to the location of the signal changes on the 3T and 7T MRI of the motor cortex. These findings indicate that the motor cortex hypointensity on 3T MRI FLAIR images in ALS is due to increased iron accumulation by microglia.

MRI findings of juvenile psoriatic arthritis

International Nuclear Information System (INIS)

Lee, Edward Y.; Kleinman, Paul K.; Sundel, Robert P.; Kim, Susan; Zurakowski, David

2008-01-01

The aim of this study was to describe the magnetic resonance imaging (MRI) features of juvenile psoriatic arthritis (JpsA) in children in order to facilitate early diagnosis and proper management. Two pediatric radiologists retrospectively reviewed in consensus a total of 37 abnormal MRI examinations from 31 pediatric patients (nine boys, 22 girls; age range 1-17 years; mean age 9.4 years) who had a definite diagnosis of JpsA and underwent MRI. Each MRI was evaluated for synovium abnormality (thickening and enhancement), joint effusion (small, moderate, and large), bone marrow abnormality (edema, enhancement, and location of abnormality), soft tissue abnormality (edema, enhancement, atrophy, and fatty infiltration), tendon abnormality (thickening, edema, tendon sheath fluid, and enhancement), and articular abnormality (joint space narrowing and erosion). The distribution of abnormal MRI findings among the six categories for the 37 MRI examinations was evaluated. The number of abnormal MRI findings for each MRI examination was assessed. Age at MRI examination and all six categories of abnormal MRI findings according to gender were evaluated. There were a total 96 abnormal MRI findings noted on 37 abnormal MRI examinations from 31 pediatric patients. The 37 abnormal MRI examinations included MRI of the hand (n=8), knee (n = 8), ankle (n = 5), pelvis (n = 5), temporomandibular joint (n = 4), wrist (n = 3), foot (n = 2), elbow (n = 1), and shoulder (n = 1). Twenty-eight diffuse synovial thickening and/or enhancement were the most common MRI abnormality (29.2%). Joint effusion comprised 22 abnormal MRI findings (22.9%). There were 16 abnormal MRI bone marrow edema and/or enhancement findings (16.7%), and in seven (7.3%) the edema involved non-articular sites. Soft tissue abnormality manifested as edema and/or enhancement constituted 14 abnormal MRI findings (14.5%). There were ten MRI abnormalities (10.4%) involving tendons. Articular abnormality seen as joint space

MRI findings of juvenile psoriatic arthritis

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Lee, Edward Y.; Kleinman, Paul K. [Harvard Medical School, Department of Radiology, Boston, MA (United States); Children' s Hospital Boston, MA (United States); Sundel, Robert P.; Kim, Susan [Harvard Medical School, Rheumatology Program, Division of Immunology and the Department of Pediatrics, Boston, MA (United States); Children' s Hospital Boston, MA (United States); Zurakowski, David [Harvard Medical School, Department of Radiology, Boston, MA (United States); Harvard Medical School, Department of Orthopaedic Surgery, Boston, MA (United States); Children' s Hospital Boston, MA (United States)

2008-11-15

The aim of this study was to describe the magnetic resonance imaging (MRI) features of juvenile psoriatic arthritis (JpsA) in children in order to facilitate early diagnosis and proper management. Two pediatric radiologists retrospectively reviewed in consensus a total of 37 abnormal MRI examinations from 31 pediatric patients (nine boys, 22 girls; age range 1-17 years; mean age 9.4 years) who had a definite diagnosis of JpsA and underwent MRI. Each MRI was evaluated for synovium abnormality (thickening and enhancement), joint effusion (small, moderate, and large), bone marrow abnormality (edema, enhancement, and location of abnormality), soft tissue abnormality (edema, enhancement, atrophy, and fatty infiltration), tendon abnormality (thickening, edema, tendon sheath fluid, and enhancement), and articular abnormality (joint space narrowing and erosion). The distribution of abnormal MRI findings among the six categories for the 37 MRI examinations was evaluated. The number of abnormal MRI findings for each MRI examination was assessed. Age at MRI examination and all six categories of abnormal MRI findings according to gender were evaluated. There were a total 96 abnormal MRI findings noted on 37 abnormal MRI examinations from 31 pediatric patients. The 37 abnormal MRI examinations included MRI of the hand (n=8), knee (n = 8), ankle (n = 5), pelvis (n = 5), temporomandibular joint (n = 4), wrist (n = 3), foot (n = 2), elbow (n = 1), and shoulder (n = 1). Twenty-eight diffuse synovial thickening and/or enhancement were the most common MRI abnormality (29.2%). Joint effusion comprised 22 abnormal MRI findings (22.9%). There were 16 abnormal MRI bone marrow edema and/or enhancement findings (16.7%), and in seven (7.3%) the edema involved non-articular sites. Soft tissue abnormality manifested as edema and/or enhancement constituted 14 abnormal MRI findings (14.5%). There were ten MRI abnormalities (10.4%) involving tendons. Articular abnormality seen as joint space

Comparison of 3D turbo spin-echo SPACE sequences with conventional 2D MRI sequences to assess the shoulder joint

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Kloth, Jost Karsten, E-mail: jost.kloth@med.uni-heidelberg.de [Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 110, D-69120 Heidelberg (Germany); Winterstein, Marianne, E-mail: marianne.winterstein@med.uni-heidelberg.de [Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 110, D-69120 Heidelberg (Germany); Akbar, Michael, E-mail: michael.akbar@med.uni-heidelberg.de [Orthopedic and Trauma Surgery, University Hospital Heidelberg, Schlierbacher Landstraße 200a, D-69118 Heidelberg (Germany); Meyer, Esther, E-mail: esther.meyer@siemens.com [Siemens Healthcare, Erlangen (Germany); Paul, Dominik, E-mail: dominik.paul@siemens.com [Siemens Healthcare, Erlangen (Germany); Kauczor, Haus-Ulrich, E-mail: hans-ulrich.kauczor@med.uni-heidelberg.de [Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 110, D-69120 Heidelberg (Germany); Weber, Marc-André, E-mail: marcandre.weber@med.uni-heidelberg.de [Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 110, D-69120 Heidelberg (Germany)

2014-10-15

Highlights: • 3D SPACE and conventional 2D TSE MRI for assessment of the shoulder joint were compared. • Concordance for most pathologys was substantial to almost perfect. • Examination time could be reduced up to 8 min (27%). • Regarding rotator cuff injuries an additional sagittal T2w TSE sequence in 3D protocol is recommended. - Abstract: Purpose: To determine the accuracy and reliability of three-dimensional (3D) T1- and proton density (PD)-weighted turbo spin-echo (TSE) sampling perfection with application-optimized contrasts using different flip-angle evolution (SPACE) compared with conventional 2D sequences in assessment of the shoulder-joint. Materials and methods: Ninety-three subjects were examined on a 3-T MRI system with both conventional 2D-TSE sequences in T1-, T2- and PD-weighting and 3D SPACE sequences in T1- and PD-weighting. All examinations were assessed independently by two reviewers for common pathologies of the shoulder-joint. Agreement between 2D- and 3D-sequences and inter-observer-agreement was evaluated using kappa-statistics. Results: Using conventional 2D TSE sequences as standard of reference, sensitivity, specificity, and accuracy values of 3D SPACE were 81.8%, 95.1%, and 93.5% for injuries of the supraspinatus-tendon (SSP), 81.3%, 93.5%, and 91.4% for the cartilage layer and 82.4%, 98.5%, and 97.5% for the long biceps tendon. Concordance between 2D and 3D was almost perfect for tendinopathies of the SSP (κ = 0.85), osteoarthritis (κ = 1), luxation of the biceps tendon (κ = 1) and adjacent bone marrow (κ = 0.92). Inter-observer-agreement was generally higher for conventional 2D TSE sequences (κ, 0.23–1.0), when compared to 3D SPACE sequences (κ, −0.33 to 1.0) except for disorders of the long biceps tendon and supraspinatus tendon rupture. Conclusion: Because of substantial and almost perfect concordance with conventional 2D TSE sequences for common shoulder pathologies, MRI examination-time can be reduced by nearly 40

Three-dimensional quantification of vorticity and helicity from 3D cine PC-MRI using finite-element interpolations.

Science.gov (United States)

Sotelo, Julio; Urbina, Jesús; Valverde, Israel; Mura, Joaquín; Tejos, Cristián; Irarrazaval, Pablo; Andia, Marcelo E; Hurtado, Daniel E; Uribe, Sergio

2018-01-01

We propose a 3D finite-element method for the quantification of vorticity and helicity density from 3D cine phase-contrast (PC) MRI. By using a 3D finite-element method, we seamlessly estimate velocity gradients in 3D. The robustness and convergence were analyzed using a combined Poiseuille and Lamb-Ossen equation. A computational fluid dynamics simulation was used to compared our method with others available in the literature. Additionally, we computed 3D maps for different 3D cine PC-MRI data sets: phantom without and with coarctation (18 healthy volunteers and 3 patients). We found a good agreement between our method and both the analytical solution of the combined Poiseuille and Lamb-Ossen. The computational fluid dynamics results showed that our method outperforms current approaches to estimate vorticity and helicity values. In the in silico model, we observed that for a tetrahedral element of 2 mm of characteristic length, we underestimated the vorticity in less than 5% with respect to the analytical solution. In patients, we found higher values of helicity density in comparison to healthy volunteers, associated with vortices in the lumen of the vessels. We proposed a novel method that provides entire 3D vorticity and helicity density maps, avoiding the used of reformatted 2D planes from 3D cine PC-MRI. Magn Reson Med 79:541-553, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

A digital 3D atlas of the marmoset brain based on multi-modal MRI.

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Liu, Cirong; Ye, Frank Q; Yen, Cecil Chern-Chyi; Newman, John D; Glen, Daniel; Leopold, David A; Silva, Afonso C

2018-04-01

The common marmoset (Callithrix jacchus) is a New-World monkey of growing interest in neuroscience. Magnetic resonance imaging (MRI) is an essential tool to unveil the anatomical and functional organization of the marmoset brain. To facilitate identification of regions of interest, it is desirable to register MR images to an atlas of the brain. However, currently available atlases of the marmoset brain are mainly based on 2D histological data, which are difficult to apply to 3D imaging techniques. Here, we constructed a 3D digital atlas based on high-resolution ex-vivo MRI images, including magnetization transfer ratio (a T1-like contrast), T2w images, and multi-shell diffusion MRI. Based on the multi-modal MRI images, we manually delineated 54 cortical areas and 16 subcortical regions on one hemisphere of the brain (the core version). The 54 cortical areas were merged into 13 larger cortical regions according to their locations to yield a coarse version of the atlas, and also parcellated into 106 sub-regions using a connectivity-based parcellation method to produce a refined atlas. Finally, we compared the new atlas set with existing histology atlases and demonstrated its applications in connectome studies, and in resting state and stimulus-based fMRI. The atlas set has been integrated into the widely-distributed neuroimaging data analysis software AFNI and SUMA, providing a readily usable multi-modal template space with multi-level anatomical labels (including labels from the Paxinos atlas) that can facilitate various neuroimaging studies of marmosets. Published by Elsevier Inc.

MRI of the lumbar spine: comparison of 3D isotropic turbo spin-echo SPACE sequence versus conventional 2D sequences at 3.0 T.

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Lee, Sungwon; Jee, Won-Hee; Jung, Joon-Yong; Lee, So-Yeon; Ryu, Kyeung-Sik; Ha, Kee-Yong

2015-02-01

Three-dimensional (3D) fast spin-echo sequence with variable flip-angle refocusing pulse allows retrospective alignments of magnetic resonance imaging (MRI) in any desired plane. To compare isotropic 3D T2-weighted (T2W) turbo spin-echo sequence (TSE-SPACE) with standard two-dimensional (2D) T2W TSE imaging for evaluating lumbar spine pathology at 3.0 T MRI. Forty-two patients who had spine surgery for disk herniation and had 3.0 T spine MRI were included in this study. In addition to standard 2D T2W TSE imaging, sagittal 3D T2W TSE-SPACE was obtained to produce multiplanar (MPR) images. Each set of MR images from 3D T2W TSE and 2D TSE-SPACE were independently scored for the degree of lumbar neural foraminal stenosis, central spinal stenosis, and nerve compression by two reviewers. These scores were compared with operative findings and the sensitivities were evaluated by McNemar test. Inter-observer agreements and the correlation with symptoms laterality were assessed with kappa statistics. The 3D T2W TSE and 2D TSE-SPACE had similar sensitivity in detecting foraminal stenosis (78.9% versus 78.9% in 32 foramen levels), spinal stenosis (100% versus 100% in 42 spinal levels), and nerve compression (92.9% versus 81.8% in 59 spinal nerves). The inter-observer agreements (κ = 0.849 vs. 0.451 for foraminal stenosis, κ = 0.809 vs. 0.503 for spinal stenosis, and κ = 0.681 vs. 0.429 for nerve compression) and symptoms correlation (κ = 0.449 vs. κ = 0.242) were better in 3D TSE-SPACE compared to 2D TSE. 3D TSE-SPACE with oblique coronal MPR images demonstrated better inter-observer agreements compared to 3D TSE-SPACE without oblique coronal MPR images (κ = 0.930 vs. κ = 0.681). Isotropic 3D T2W TSE-SPACE at 3.0 T was comparable to 2D T2W TSE for detecting foraminal stenosis, central spinal stenosis, and nerve compression with better inter-observer agreements and symptom correlation. © The Foundation Acta Radiologica 2014 Reprints and

Magnetic Resonance Imaging (MRI) of TMJ. Inter-observer influence on diagnosis or therapy and difference of interpretation regarding abnormal signs

International Nuclear Information System (INIS)

Iinuma, Hideto; Minowa, Kazuyuki; Kobayashi, Ichizou; Matsuda, Akemi; Kaneko, Masayuki

2006-01-01

The purpose of study was to evaluate the influence of a head and neck radiologist after MRI examinations of the temporomandibular joint on the therapeutic strategy in patients with temporomandibular disorders and, furthermore, to analyze interobserver agreement for defined MRI criteria. Eighteen patients including 36 TMJ (10 males and 8 females; age 15-53 years) were enrolled. All were clinically evaluated, diagnosed ''TMD'' and MRI examinations were performed. The medical and MRI records of 18 patients were retrospectively reviewed. Four MR images (proton density, T1, T2-weighted and Gd-DTPA enhanced sagittal images at the open and closed mouth) were obtained. Therapeutic strategies before and after performance of the MRI were compared. One radiologist and main dentist independently analyzed the sagittal MR images for position of the disk, position of the condyle, signal intensity of the disk and bilaminar zone, bone changes and several additional findings. Additionally, the agreement between one radiologist and main dentist with respect to the diagnoses was evaluated. There were 13 cases that the modification of diagnosis was needed after MRI examinations. In 10 of the 18 subjective symptom-free subjects, there were abnormal signs anatomically. Also in 1 subjective and objective symptom-free subjects, abnormal signs were seen on MRI. In 1 individual, MRI revealed larger abnormal signs in clinically asymptomatic TMJ as compared with symptomatic TMJ. Whereas as for 1 symptomatic subject, Abnormal signs could not be identified in any of the TMJs. There were no cases that the change of treatment methods was needed after MRI examinations, but as for 13 cases, the correction of treatment contents was needed, such as the changes of the therapeutic regimen and the form of the sprint were registered after MRI. The disagreement between one radiologist and main dentist was seen in: the bone change of condyle; 30 TMJs, the change of temporal bone ;6 TMJs, the relationship

Frequency of brain MRI abnormalities in neuromyelitis optica spectrum disorder at presentation: A cohort of Latin American patients.

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Carnero Contentti, Edgar; Daccach Marques, Vanessa; Soto de Castillo, Ibis; Tkachuk, Veronica; Antunes Barreira, Amilton; Armas, Elizabeth; Chiganer, Edson; de Aquino Cruz, Camila; Di Pace, José Luis; Hryb, Javier Pablo; Lavigne Moreira, Carolina; Lessa, Carmen; Molina, Omaira; Perassolo, Monica; Soto, Arnoldo; Caride, Alejandro

2018-01-01

Brain magnetic resonance imaging (BMRI) lesions were classically not reported in neuromyelitis optica (NMO). However, BMRI lesions are not uncommon in NMO spectrum disorder (NMOSD) patients. To report BMRI characteristic abnormalities (location and configuration) in NMOSD patients at presentation. Medical records and BMRI characteristics of 79 patients with NMOSD (during the first documented attack) in Argentina, Brazil and Venezuela were reviewed retrospectively. BMRI abnormalities were observed in 81.02% of NMOSD patients at presentation. Forty-two patients (53.1%) showed typical-NMOSD abnormalities. We found BMRI abnormalities at presentation in the brainstem/cerebellum (n = 26; 32.9%), optic chiasm (n = 16; 20.2%), area postrema (n = 13; 16.4%), thalamus/hypothalamus (n = 11; 13.9%), corpus callosum (n = 11; 13.9%), periependymal-third ventricle (n = 9; 11.3%), corticospinal tract (n = 7; 8.8%), hemispheric white matter (n = 1; 1.2%) and nonspecific areas (n = 49; 62.03%). Asymptomatic BMRI lesions were more common. The frequency of brain MRI abnormalities did not differ between patients who were positive and negative for aquaporin 4 antibodies at presentation. Typical brain MRI abnormalities are frequent in NMOSD at disease onset. Copyright © 2017 Elsevier B.V. All rights reserved.

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.)

CAIPIRINHA accelerated SPACE enables 10-min isotropic 3D TSE MRI of the ankle for optimized visualization of curved and oblique ligaments and tendons.

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Kalia, Vivek; Fritz, Benjamin; Johnson, Rory; Gilson, Wesley D; Raithel, Esther; Fritz, Jan

2017-09-01

To test the hypothesis that a fourfold CAIPIRINHA accelerated, 10-min, high-resolution, isotropic 3D TSE MRI prototype protocol of the ankle derives equal or better quality than a 20-min 2D TSE standard protocol. Following internal review board approval and informed consent, 3-Tesla MRI of the ankle was obtained in 24 asymptomatic subjects including 10-min 3D CAIPIRINHA SPACE TSE prototype and 20-min 2D TSE standard protocols. Outcome variables included image quality and visibility of anatomical structures using 5-point Likert scales. Non-parametric statistical testing was used. P values ≤0.001 were considered significant. Edge sharpness, contrast resolution, uniformity, noise, fat suppression and magic angle effects were without statistical difference on 2D and 3D TSE images (p > 0.035). Fluid was mildly brighter on intermediate-weighted 2D images (p acceleration enables high-spatial resolution oblique and curved planar MRI of the ankle and visualization of ligaments, tendons and joints equally well or better than a more time-consuming anisotropic 2D TSE MRI. • High-resolution 3D TSE MRI improves visualization of ankle structures. • Limitations of current 3D TSE MRI include long scan times. • 3D CAIPIRINHA SPACE allows now a fourfold-accelerated data acquisition. • 3D CAIPIRINHA SPACE enables high-spatial-resolution ankle MRI within 10 min. • 10-min 3D CAIPIRINHA SPACE produces equal-or-better quality than 20-min 2D TSE.

3D-FIESTA MRI at 3 T demonstrating branches of the intraparotid facial nerve, parotid ducts and relation with benign parotid tumours

International Nuclear Information System (INIS)

Li Chuanting; Li Yan; Zhang Dongsheng; Yang Zhenzhen; Wu Lebin

2012-01-01

Aim: To investigate the usefulness of three-dimensional (3D) fast imaging employing steady state precession (FIESTA) magnetic resonance imaging (MRI) at 3 T in evaluating the intraparotid components of the facial nerve and parotid ducts, and to compare the MRI images with surgical findings. Materials and methods: Thirty-one cases of benign parotid tumours were studied with conventional and 3D FIESTA MRI sequences at 3T using a head coil. The most clinically useful 3D FIESTA images were acquired at parameters of 4.9 ms repetition time (TR); 1.5 effective echo time (TEeff); a flip of 55°, a field of view of 18 to 20 cm, a matrix of 512 × 320, an axial plane, no gaps, and a section thickness of 1 mm. Post-processed multiplanar images were obtained with an Advantage Windows (AW sdc 4.3) workstation. Parotid ducts, facial nerves, and tumours were identified on these images. The relationship of the tumours to the facial nerves and parotid ducts was confirmed at surgery. Results: The facial nerves appeared as linear structures of low intensity. The main trunk of the facial nerve was identified bilaterally in 93.5% of the 3D-FIESTA sequence images. Parotid ducts appeared as structures of high intensity on multiplanar 3D-FIESTA images (100%). The relationships of the tumours with the cervicofacial and temporofacial divisions of the facial nerve were correctly diagnosed in 26 of 31 cases (83.9%) using 3D-FIESTA sequence images. Conclusion: 3D-FIESTA MRI at 3 T depicted the main trunk, cervicofacial and temporofacial divisions of the facial nerve, and the main parotid duct. It is useful for preoperative evaluation of parotid gland tumours.

A hybrid approach for fusing 4D-MRI temporal information with 3D-CT for the study of lung and lung tumor motion.

Science.gov (United States)

Yang, Y X; Teo, S-K; Van Reeth, E; Tan, C H; Tham, I W K; Poh, C L

2015-08-01

Accurate visualization of lung motion is important in many clinical applications, such as radiotherapy of lung cancer. Advancement in imaging modalities [e.g., computed tomography (CT) and MRI] has allowed dynamic imaging of lung and lung tumor motion. However, each imaging modality has its advantages and disadvantages. The study presented in this paper aims at generating synthetic 4D-CT dataset for lung cancer patients by combining both continuous three-dimensional (3D) motion captured by 4D-MRI and the high spatial resolution captured by CT using the authors' proposed approach. A novel hybrid approach based on deformable image registration (DIR) and finite element method simulation was developed to fuse a static 3D-CT volume (acquired under breath-hold) and the 3D motion information extracted from 4D-MRI dataset, creating a synthetic 4D-CT dataset. The study focuses on imaging of lung and lung tumor. Comparing the synthetic 4D-CT dataset with the acquired 4D-CT dataset of six lung cancer patients based on 420 landmarks, accurate results (average error lung details, and is able to show movement of lung and lung tumor over multiple breathing cycles.

3 Tesla proton MRI for the diagnosis of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia: initial results in comparison to HRCT.

Science.gov (United States)

Attenberger, U I; Morelli, J N; Henzler, T; Buchheidt, D; Fink, C; Schoenberg, S O; Reichert, M

2014-01-01

To evaluate the diagnostic accuracy of 3 Tesla proton MRI for the assessment of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia. In a prospective study, 3 Tesla MRI was performed in 19 febrile neutropenic patients (5 women, 14 men; mean age 61 years ± 14.2; range 23-77 years). All patients underwent high-resolution CT less than 24h prior to MRI. The MRI protocol (Magnetom Tim Trio, Siemens) included a T2-weighted HASTE sequence (TE/TR: 49 ms/∞, slice thickness 6mm) and a high-resolution 3D VIBE sequence with an ultra-short TETesla MRI with a sensitivity of 82.3% and a specificity of 78.6%, resulting in an overall accuracy of 88% (NPV/PPV 66.7%/89.5%). In 51 lobes (19 of 19 patients), pulmonary abnormalities visualized by MR were judged to be concordant in their location and in the lesion type identified by both readers. In 22 lobes (11 of 19 patients), no abnormalities were present on either MR or HRCT (true negative). In 6 lobes (5 of 19 patients), ground glass opacity areas were detected on MRI but were not visible on HRCT (false positives). In 11 lobes (7 of 19 patients), MRI failed to detect ground glass opacity areas identified by HRCT. However, since the abnormalities were disseminated in these patients, accurate treatment decisions were possible in every case based on MRI. In one case MRI showed a central area of cavitation, which was not visualized by HRCT. Infectious nodules and consolidations can be detected in neutropenic patients with acute myeloid leukemia with a sufficient diagnostic accuracy by 3 Tesla MRI. Detection of ground glass opacity areas is the main limitation of 3-Tesla MRI when compared to HRCT. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

MRCP and 3D LAVA imaging of extrahepatic cholangiocarcinoma at 3 T MRI

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Li, N.; Liu, C.; Bi, W.; Lin, X.; Jiao, H. [Shandong Medical Imaging Research Institute, Shandong University, Jinan (China); Zhao, P., E-mail: Gavinsdu@163.com [Department of Radiology, Shandong Provincial Hospital, Shandong University, Jinan (China)

2012-06-15

Extrahepatic cholangiocarcinoma (CCA) is a primary bile duct malignant tumour with poor prognosis. Familiarity with their varied imaging characteristics can be helpful in developing a correct diagnosis and in optimal treatment planning, and thus contribute to a better prognosis. The purpose of this article is to illustrate the typical appearances of extrahepatic CCA on magnetic resonance cholangiopancreatography (MRCP) and three-dimensional (3D) LAVA (liver acquisition with volume acceleration) sequences at 3 T magnetic resonance imaging (MRI), and to discuss the superiority of the two techniques in the diagnosis of CCA.

SU-E-J-209: Geometric Distortion at 3T in a Commercial 4D MRI-Compatible Phantom

International Nuclear Information System (INIS)

Fatemi-Ardekani, A; Wronski, M; Kim, A; Stanisz, G; Sarfehnia, A; Keller, B

2015-01-01

Purpose: There are very few commercial 4D phantoms that are marketed as MRI compatible. We are evaluating one such commercial phantom, made to be used with an MRI-Linear accelerator. The focus of this work is to characterize the geometric distortions produced in this phantom at 3T using 3 clinical MR pulse sequences. Methods: The CIRS MRI-Linac Dynamic Phantom (CIRSTM) under investigation in this study consists of a softwaredriven moving tumour volume within a thorax phantom body and enables dose accumulation by placing a dosimeter within the tumour volume. Our initial investigation is to evaluate the phantom in static mode prior to examining its 4D capability. The water-filled thorax phantom was scanned using a wide-bore Philips 3T Achieva MRI scanner employing a Thoracic xl coil and clinical 2D T1W FFE, 2D T1W TSE and 3D T1W TFE pulse sequences. Each of the MR image sets was rigidly fused with a reference CT image of the phantom employing a rigid registration with 6 degrees of freedom. Geometric distortions between the MR and CT image sets were measured in 3 dimensions at selected points along the periphery of the distortion grid embedded within the phantom body (11.5, 7.5 and 3 cm laterally, ant/post and sup/inf of magnetic isocenter respectively). Results: The maximal measured geometric distortions between the MR and reference CT points of interest were 0.9, 1.8 and 1.3 mm in the lateral, anteriorposterior and cranio-caudal directions, respectively. For all 3 spatial dimensions, the maximal distortions occurred for the FFE pulse sequence. Maximal distortions for the 2D FFE, 2D TSE and 3D TFE sequences were 1, 0.7 and 1.8 mm, respectively. Conclusion: Our initial static investigation of this phantom shows minimal geometric distortions at 3T along the periphery of the embedded grid. CIRS has provided us with a phantom at no charge for evaluation at 3 Tesla

Role of combined DWIBS/3D-CE-T1w whole-body MRI in tumor staging: Comparison with PET-CT

International Nuclear Information System (INIS)

Manenti, Guglielmo; Cicciò, Carmelo; Squillaci, Ettore; Strigari, Lidia; Calabria, Ferdinando; Danieli, Roberta

2012-01-01

Objectives: To assess the diagnostic performance of whole-body magnetic resonance imaging (WB-MRI) by diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) in malignant tumor detection and the potential diagnostic advantages in generating fused DWIBS/3D-contrast enhanced T1w (3D-CE-T1w) images. Methods: 45 cancer patients underwent 18F-FDG PET-CT and WB-MRI for staging purpose. Fused DWIBS/3D-CE T1w images were generated off-line. 3D-CE-T1w, DWIBS images alone and fused with 3D-CE T1w were compared by two readers groups for detection of primary diseases and local/distant metastases. Diagnostic performance between the three WB-MRI data sets was assessed using receiver operating characteristic (ROC) curve analysis. Imaging exams and histopathological results were used as standard of references. Results: Areas under the ROC curves of DWIBS vs. 3D-CE-T1w vs. both sequences in fused fashion were 0.97, 0.978, and 1.00, respectively. The diagnostic performance in tumor detection of fused DWIBS/3D-CE-T1w images were statistically superior to DWIBS (p < 0.001) and 3D-CE-T1w (p ≤ 0.002); while the difference between DWIBS and 3D-CE-T1w did not show statistical significance difference. Detection rates of malignancy did not differ between WB-MRI with DWIBS and 18F-FDG PET-CT. Conclusion: WB-MRI with DWIBS is to be considered as alternative tool to conventional whole-body methods for tumor staging and during follow-up in cancer patients.

Measurement of CSF volume with 3D-FASE MRI

International Nuclear Information System (INIS)

Kanayama, Shoichi; Calderon, A.; Makita, Jun-ichi; Ohara, Yukou; Tsunoda, Akira; Sato, Kiyoshi.

1997-01-01

A noninvasive and fast cerebrospinal fluid (CSF) volume measurement method has been developed using 3D-FASE MRI and a semi-automatic segmentation process. Images with a high CSF/(gray and white matter) ratio (about 10-20) were obtained with a heavily T 2 weighted 3D-FASE sequence. The CSF region was segmented with a region growing method and the volume was calculated from the number of segmented voxels with a signal intensity weighted summation. Total measurement time was about 30 minutes for each study. The errors of the measured volumes were within 10% for the phantom experiments. Intracranial CSF volumes of normal volunteers ranged between about 100 and 200 cc and the ventricle/intracranial CSF ratio was about 10%. 3D display of the segmented intracranial and ventricle CSF regions was also carried out and proved to be useful to understand the anatomy. Increased intracranial and/or ventricle CSF volumes were obtained for a hydrocephalic patient and one patient with probable cerebral atrophy. The results suggest that the developed method could be used for the diagnosis of patients with neurological diseases. (author)

Feasibility and evaluation of dual-source transmit 3D imaging of the orbits: Comparison to high-resolution conventional MRI at 3T

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Seeger, Achim, E-mail: achim.seeger@gmx.de [Department of Diagnostic and Interventional Neuroradiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, Tübingen 72076 (Germany); Schulze, Maximilian, E-mail: maximilian.schulze@med.uni-tuebingen.de [Department of Diagnostic and Interventional Neuroradiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, Tübingen 72076 (Germany); Schuettauf, Frank, E-mail: fschuettauf@uni-tuebingen.de [University Eye Hospital, Department of Ophthalmology, Eberhard-Karls-University, Schleichstrasse 12, Tübingen 72076 (Germany); Klose, Uwe, E-mail: uwe.klose@med.uni-tuebingen.de [Department of Diagnostic and Interventional Neuroradiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, Tübingen 72076 (Germany); Ernemann, Ulrike, E-mail: ulrike.ernemann@med.uni-tuebingen.de [Department of Diagnostic and Interventional Neuroradiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, Tübingen 72076 (Germany); Hauser, Till-Karsten, E-mail: till-karsten.hauser@med.uni-tuebingen.de [Department of Diagnostic and Interventional Neuroradiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, Tübingen 72076 (Germany)

2015-06-15

Highlights: • Reduced FOV imaging enables a 3D approach for a very fast assessment of the orbits. • Conventional MRI exhibited higher eSNR values and consecutively higher scores for overall image quality in the subjective readers’ analysis. • All pathologies could be detected compared to high-resolution conventional MRI making 3D pTX SPACE to a potential alternative and fast imaging technique. - Abstract: Purpose: To prospectively compare the image quality and diagnostic performance of orbital MR images obtained by using a dual-source parallel transmission (pTX) 3D sequence (Sampling Perfection with Application optimized Contrasts using different flip angle Evolution, SPACE) with the image quality of conventional high-resolution standard protocol for clinical use in patients at 3T. Materials and methods: After obtaining institutional review board approval and patient consent, 32 patients with clinical indication for orbital MRI were examined using a high-resolution conventional sequences and 3D pTX SPACE sequences. Quantitative measurements, image quality of the healthy orbit, incidence of artifacts, and the subjective diagnostic performance to establish diagnosis was rated. Statistical significance was calculated by using a Student's t-test and nonparametric Wilcoxon signed rank test. Results: Length measurements were comparable in the two techniques, 3D pTX SPACE resulted in significant faster image acquisition with higher spatial resolution and less motion artifacts as well as better delineation of the optic nerve sheath. However, estimated contrast-to-noise and signal-to-noise and overall image quality as well as subjective scores of the conventional TSE imaging were rated significantly higher. The conventional MR sequences were the preferred techniques by the readers. Conclusion: This study demonstrates the feasibility of 3D pTX SPACE of the orbit resulting in a rapid acquisition of isotropic high-resolution images. Although no pathology was

3D-Printed Patient-Specific ACL Femoral Tunnel Guide from MRI.

Science.gov (United States)

Rankin, Iain; Rehman, Haroon; Frame, Mark

2018-01-01

Traditional ACL reconstruction with non-anatomic techniques can demonstrate unsatisfactory long-term outcomes with regards instability and the degenerative knee changes observed with these results. Anatomic ACL reconstruction attempts to closely reproduce the patient's individual anatomic characteristics with the aim of restoring knee kinematics, in order to improve patient short and long-term outcomes. We designed an arthroscopic, patient-specific, ACL femoral tunnel guide to aid anatomical placement of the ACL graft within the femoral tunnel. The guide design was based on MRI scan of the subject's uninjured contralateral knee, identifying the femoral footprint and its anatomical position relative to the borders of the femoral articular cartilage. Image processing software was used to create a 3D computer aided design which was subsequently exported to a 3D-printing service. Transparent acrylic based photopolymer, PA220 plastic and 316L stainless steel patient-specific ACL femoral tunnel guides were created; the models produced were accurate with no statistical difference in size and positioning of the center of the ACL femoral footprint guide to MRI ( p =0.344, p =0.189, p =0.233 respectively). The guides aim to provide accurate marking of the starting point of the femoral tunnel in arthroscopic ACL reconstruction. This study serves as a proof of concept for the accurate creation of 3D-printed patient-specific guides for the anatomical placement of the femoral tunnel during ACL reconstruction.

Quantitative Comparison of 2D and 3D MRI Techniques for the Evaluation of Chondromalacia Patellae in 3.0T MR Imaging of the Knee

Directory of Open Access Journals (Sweden)

Ali Özgen

2016-09-01

Full Text Available INTRODUCTION: Chondromalacia patellae is a very common disorder of patellar cartilage. Magnetic resonance imaging (MRI is a powerful non-invasive tool to investigate patellar cartilage lesions. Although many MRI sequences have been used in MR imaging of the patellar cartilage and the optimal pulse sequence is controversial, fat-saturated proton density images have been considered very valuable to evaluate patellar cartilage. The purpose of this study is to quantitatively compare the diagnostic performance of various widely used 2D and 3D MRI techniques for the evaluation of chondromalacia patellae in 3.0T MR imaging of the knee using T2 mapping images as the reference standard. METHODS: Sevety-five knee MRI exams of 69 adult consecutive were included in the study. Fat-saturated T2-weighted (FST2, fat-saturated proton density (FSPD, water-only T2-weighted DIXON (T2mD, T2-weighted 3 dimensional steady state (3DT2FFE, merged multi-echo steady state (3DmFFE, and water selective T1-weighted fat-supressed (WATSc images were acquired. Quantitative comparison of grade 1 and grade 5 lesions were made using contrast-to-noise (CNR ratios. Grade 2-4 lesions were scored qualitatively and scorings of the lesions were compared statistically. Analysis of variance and Tukey’s tests were used to compare CNR data. Two sample z-test was used to compare the ratio of MR exams positive for grade 1 lesions noted on T2-mapping and other conventional sequences. Paired samples t-test was used to compare two different pulse sequences. RESULTS: In detecting grade 1 lesions, FSPD, FST2 and T2mD images were superior in comparison to other sequences. FSPD and FST2 images were statistically superior in detecting grade 2-4 lesions. Although all grade 5 lesions were noted in every single sequence, FST2 images have the highest mean CNR followed by 3DT2FFE images. DISCUSSION AND CONCLUSION: FST2 sequence is equal or superior in detecting every grade of patellar chondromalacia in

CT reconstruction and MRI fusion of 3D rotational angiography in the evaluation of pediatric cerebrovascular lesions

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Muthusami, Prakash; Rea, Vanessa; Shroff, Manohar [The Hospital for Sick Children, Pediatric Neuroradiology and Image Guided Therapy, Department of Diagnostic Imaging, Toronto, ON (Canada); Shkumat, Nicholas [The Hospital for Sick Children, Medical Physics, Department of Diagnostic Imaging, Toronto, ON (Canada); Chiu, Albert H. [Institute of Neurological Sciences, Prince of Wales Hospital, Department of Interventional Neuroradiology, Randwick, NSW (Australia)

2017-06-15

Complex neurovascular lesions in children require precise anatomic understanding for treatment planning. Although 3DRA is commonly employed for volumetric reformation in neurointerventional procedures, the ability to reconstruct this data into CT-like images (3DRA-CT) is not widely utilized. This study demonstrates the feasibility and usefulness of 3DRA-CT and subsequent MRI fusion for problem solving in pediatric neuroangiography. This retrospective study includes 18 3DRA-CT studies in 16 children (age 9.6 ± 3.8 years, range 2-16 years) over 1 year. After biplane 2D-digital subtraction angiography (DSA), 5-second 3DRA was performed with selective vessel injection either with or without subtraction. Images were reconstructed into CT sections which were post-processed to generate multiplanar reformation (MPR) and maximum intensity projection (MIP) images. Fusion was performed with 3D T1 MRI images to precisely demonstrate neurovascular relationships. Quantitative radiation metrics were extracted and compared against those for the entire examination and for corresponding biplane 2D-DSA acquisitions. In all 18 cases, the 3DRA procedure and MRI fusion were technically successful and provided clinically useful information relevant to management. The unsubtracted and subtracted 3DRA acquisitions were measured to deliver 5.9 and 132.2%, respectively, of the mean radiation dose of corresponding biplane 2D-DSA acquisitions and contributed 1.2 and 12.5%, respectively, to the total procedure dose. Lower radiation doses, high spatial resolution, and multiplanar reformatting capability make 3DRA-CT a useful adjunct to evaluate neurovascular lesions in children. Fusing 3DRA-CT data with MRI is an additional capability that can further enhance diagnostic information. (orig.)

3D knee segmentation based on three MRI sequences from different planes.

Science.gov (United States)

Zhou, L; Chav, R; Cresson, T; Chartrand, G; de Guise, J

2016-08-01

In clinical practice, knee MRI sequences with 3.5~5 mm slice distance in sagittal, coronal, and axial planes are often requested for the knee examination since its acquisition is faster than high-resolution MRI sequence in a single plane, thereby reducing the probability of motion artifact. In order to take advantage of the three sequences from different planes, a 3D segmentation method based on the combination of three knee models obtained from the three sequences is proposed in this paper. In the method, the sub-segmentation is respectively performed with sagittal, coronal, and axial MRI sequence in the image coordinate system. With each sequence, an initial knee model is hierarchically deformed, and then the three deformed models are mapped to reference coordinate system defined by the DICOM standard and combined to obtain a patient-specific model. The experimental results verified that the three sub-segmentation results can complement each other, and their integration can compensate for the insufficiency of boundary information caused by 3.5~5 mm gap between consecutive slices. Therefore, the obtained patient-specific model is substantially more accurate than each sub-segmentation results.

A New Promising Technique of 3D Isovoxel Imaging Using 3T MRI in the Wrist: Comparison with 3T MR Arthrography

International Nuclear Information System (INIS)

Lee, Guen Young; Kim, Baek Hyun; Park, Jong Woong

2011-01-01

We wanted to evaluate the usefulness of 3D isovoxel MR imaging using 3T MRI in the wrist joint, as compared with 3T MR arthrography. A total of 33 patients underwent both MR arthrography and 3D isovoxel imaging of the wrist joints using 3T MR, including 11 patients with arthroscopic confirmation. 3D isovoxel MR imaging was performed using an intermediateweighted fast spin echo coronal scan with a 0.4-mm slice thickness and the axial images were reconstructed with a 1-mm slice thickness. One radiologist evaluated for the presence of scapholunate or lunotriquetral ligament tear and she determined the grade of the triangular fibrocartilage complex tear and chondromalacia with its location. We compared the two examinations using kappa values. The rates of detecting wrist injury were similar for both exams with substantial to almost perfect inter-examination agreement (kappa value = 0.864 for scapholunate ligament tear, 0.835 for lunotriquetral ligament tear, 0.799 for TFCC tear and 0.940 for chondromalacia). For the eleven cases that underwent arthroscopy, their results of 3D isovoxel MRI were also similar to that of MR arthrography. 3D isovoxel MR imaging is useful for the evaluation of the wrist joint

A New Promising Technique of 3D Isovoxel Imaging Using 3T MRI in the Wrist: Comparison with 3T MR Arthrography

Energy Technology Data Exchange (ETDEWEB)

Lee, Guen Young; Kim, Baek Hyun; Park, Jong Woong [Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of)

2011-02-15

We wanted to evaluate the usefulness of 3D isovoxel MR imaging using 3T MRI in the wrist joint, as compared with 3T MR arthrography. A total of 33 patients underwent both MR arthrography and 3D isovoxel imaging of the wrist joints using 3T MR, including 11 patients with arthroscopic confirmation. 3D isovoxel MR imaging was performed using an intermediateweighted fast spin echo coronal scan with a 0.4-mm slice thickness and the axial images were reconstructed with a 1-mm slice thickness. One radiologist evaluated for the presence of scapholunate or lunotriquetral ligament tear and she determined the grade of the triangular fibrocartilage complex tear and chondromalacia with its location. We compared the two examinations using kappa values. The rates of detecting wrist injury were similar for both exams with substantial to almost perfect inter-examination agreement (kappa value = 0.864 for scapholunate ligament tear, 0.835 for lunotriquetral ligament tear, 0.799 for TFCC tear and 0.940 for chondromalacia). For the eleven cases that underwent arthroscopy, their results of 3D isovoxel MRI were also similar to that of MR arthrography. 3D isovoxel MR imaging is useful for the evaluation of the wrist joint

Fast CSF MRI for brain segmentation; Cross-validation by comparison with 3D T1-based brain segmentation methods.

Science.gov (United States)

van der Kleij, Lisa A; de Bresser, Jeroen; Hendrikse, Jeroen; Siero, Jeroen C W; Petersen, Esben T; De Vis, Jill B

2018-01-01

In previous work we have developed a fast sequence that focusses on cerebrospinal fluid (CSF) based on the long T2 of CSF. By processing the data obtained with this CSF MRI sequence, brain parenchymal volume (BPV) and intracranial volume (ICV) can be automatically obtained. The aim of this study was to assess the precision of the BPV and ICV measurements of the CSF MRI sequence and to validate the CSF MRI sequence by comparison with 3D T1-based brain segmentation methods. Ten healthy volunteers (2 females; median age 28 years) were scanned (3T MRI) twice with repositioning in between. The scan protocol consisted of a low resolution (LR) CSF sequence (0:57min), a high resolution (HR) CSF sequence (3:21min) and a 3D T1-weighted sequence (6:47min). Data of the HR 3D-T1-weighted images were downsampled to obtain LR T1-weighted images (reconstructed imaging time: 1:59 min). Data of the CSF MRI sequences was automatically segmented using in-house software. The 3D T1-weighted images were segmented using FSL (5.0), SPM12 and FreeSurfer (5.3.0). The mean absolute differences for BPV and ICV between the first and second scan for CSF LR (BPV/ICV: 12±9/7±4cc) and CSF HR (5±5/4±2cc) were comparable to FSL HR (9±11/19±23cc), FSL LR (7±4, 6±5cc), FreeSurfer HR (5±3/14±8cc), FreeSurfer LR (9±8, 12±10cc), and SPM HR (5±3/4±7cc), and SPM LR (5±4, 5±3cc). The correlation between the measured volumes of the CSF sequences and that measured by FSL, FreeSurfer and SPM HR and LR was very good (all Pearson's correlation coefficients >0.83, R2 .67-.97). The results from the downsampled data and the high-resolution data were similar. Both CSF MRI sequences have a precision comparable to, and a very good correlation with established 3D T1-based automated segmentations methods for the segmentation of BPV and ICV. However, the short imaging time of the fast CSF MRI sequence is superior to the 3D T1 sequence on which segmentation with established methods is performed.

3T MRI of the knee with optimised isotropic 3D sequences. Accurate delineation of intra-articular pathology without prolonged acquisition times

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Abdulaal, Osamah M.; Rainford, Louise; Galligan, Marie; McGee, Allison [University College Dublin, Radiography and Diagnostic Imaging, School of Medicine, Belfield, Dublin (Ireland); MacMahon, Peter; Kavanagh, Eoin [Mater Misericordiae University Hospital, Department of Radiology, Dublin (Ireland); University College Dublin, School of Medicine, Dublin (Ireland); Cashman, James [Mater Misericordiae University Hospital, Department of Orthopaedics, Dublin (Ireland); University College Dublin, School of Medicine, Dublin (Ireland)

2017-11-15

To investigate optimised isotropic 3D turbo spin echo (TSE) and gradient echo (GRE)-based pulse sequences for visualisation of articular cartilage lesions within the knee joint. Optimisation of experimental imaging sequences was completed using healthy volunteers (n=16) with a 3-Tesla (3T) MRI scanner. Imaging of patients with knee cartilage abnormalities (n=57) was then performed. Acquired sequences included 3D proton density-weighted (PDW) TSE (SPACE) with and without fat-suppression (FS), and T2*W GRE (TrueFISP) sequences, with acquisition times of 6:51, 6:32 and 5:35 min, respectively. One hundred sixty-one confirmed cartilage lesions were detected and categorised (Grade II n=90, Grade III n=71). The highest sensitivity and specificity for detecting cartilage lesions were obtained with TrueFISP with values of 84.7% and 92%, respectively. Cartilage SNR mean for PDW SPACE-FS was the highest at 72.2. TrueFISP attained the highest CNR means for joint fluid/cartilage (101.5) and joint fluid/ligament (156.5), and the lowest CNR for cartilage/meniscus (48.5). Significant differences were identified across the three sequences for all anatomical structures with respect to SNR and CNR findings (p-value <0.05). Isotropic TrueFISP at 3T, optimised for acquisition time, accurately detects cartilage defects, although it demonstrated the lowest contrast between cartilage and meniscus. (orig.)

[Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering].

Science.gov (United States)

Günther, P; Tröger, J; Holland-Cunz, S; Waag, K L; Schenk, J P

2006-08-01

Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this.A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning.

Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering

International Nuclear Information System (INIS)

Guenther, P.; Holland-Cunz, S.; Waag, K.L.

2006-01-01

Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this. A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning. (orig.) [de

Usefulness of 3D-VIBE method in breast dynamic MRI. Imaging parameters and contrasting effects

International Nuclear Information System (INIS)

Uchikoshi, Masato; Ueda, Takashi; Nishiki, Shigeo; Satou, Kouichi; Wada, Akihiko; Imaoka, Izumi; Matsuo, Michimasa

2003-01-01

MR imaging (MRI) has been reported to be a useful modality to characterize breast tumors and to evaluate disease extent. Contrast-enhanced dynamic MRI, in particular, allows breast lesions to be characterized with high sensitivity and specificity. Our study was designed to develop three-dimensional volumetric interpolated breath-hold examination (3D-VIBE) techniques for the evaluation of breast tumors. First, agarose/Gd-DTPA phantoms with various concentrations of Gd-DTPA were imaged using 3D-VIBE and turbo spin echo (TSE). Second, one of the phantoms was imaged with 3D-VIBE using different flip angles. Finally, water excitation (WE) and a chemical shift-selective (CHESS) pulse were applied to the images. Each image was analyzed for signal intensity, signal-to-noise ratio (1.25*Ms/Mb) (SNR), and contrast ratio [(Ms1-Ms2)/{(Ms1+Ms2)/2}]. The results showed that 3D-VIBE provided better contrast ratios with a linear fit than TSE, although 3D-VIBE showed a lower SNR. To reach the best contrast ratio, the optimized flip angle was found to be 30 deg for contrast-enhanced dynamic study. Both WE and CHESS pulses were reliable for obtaining fat- suppressed images. In conclusion, the 3D-VIBE technique can image the entire breast area with high resolution and provide better contrast than TSE. Our phantom study suggests that optimized 3D-VIBE may be useful for the assessment of breast tumors. (author)

Guided Interventions for Prostate Cancer Using 3D-Transurethral Ultrasound and MRI Fusion

Science.gov (United States)

2017-06-01

stitching of the images and 3D reconstruction for both the TUUS and MRI images was accomplished using a free DICOM medical imaging software called...References: i. David R. Holmes III, Brian J. Davis, Christopher C. Goulet, Torrence M. Wilson, Lance A. Mynderse, Keith M. Furutani, Jon J. Camp

3D MRI findings of anterior cruciate ligament reconstruction at follow-up

International Nuclear Information System (INIS)

Deng Jun; Liang Biling; Chen Jianyu; Huang Suiqiao; Zhong Jinglian; Li Xiao

2011-01-01

Objective: To investigate the postoperative 3D MRI appearances and their evolvement patterns of ACL grafts and bone tunnels at follow-up. Methods: There were 2,6 double bundles ACL reconstructions and 16 single bundle ACL reconstructions, and a total of 56 follow-up 3D MR Imaging. MR images were reconstructed with MPR technique to evaluate grafts, bone tunnels, fixers and associated complications. Proportions of grafts with hypointensity or hyperintensity and occurrence rates of marrow edema around bone tunnels were calculated respectively among groups of different periods after operation. Results: There were 2, 4 grafts of hypointensity and 32 grafts of hyperintensity. Grafts of 2 cases were suspended with cross pins within femoral tunnels, graft of 1 case was suspended with an endobutton within the femoral tunnel, and grafts of other sites were fixed with interference screws. In the three periods as 3 months, 6 to 9 months and over 12 months after cruciate ligament reconstruction, proportions of hypointensive grafts were 20/25, 0/14 and 4/10 respectively, while proportions of hyperintensive grafts were 5/25, 14/14 and 6/10 respectively, occurrence proportions of marrow edema around bone tunnels were 54/54, 10/32 and 4/26 respectively. There was 1 tear graft, 4 tibial tunnels placed anteriorly with ACL graft impingement on the intercondylar roof, 3 femoral tunnels placed anteriorly, and 2 bone tunnels with mismatching interference screws. Conclusion: 3D MRI can accurately demonstrate the state of ACL grafts, bone tunnels, fixers and associated complications. Intensity of grafts presented a rise and reduce pattern after operation. (authors)

3D MRI of the colon: methods and first results of 5 patients; 3D-MRT des Kolons: Methodik und erste Ergebnisse

Energy Technology Data Exchange (ETDEWEB)

Luboldt, W; Bauerfeind, P; Pelkonen, P; Steiner, P; Krestin, G P; Debatin, J F [MRI-Zentrum, Dept. Diagnostische Radiologie, Universitaetsspital, Zurich (Switzerland)

1997-09-01

Purpose: `Exoscopic` and endoscopic identification of colorectal pathologies via MRI. Methods: 5 patients (36-88 years), two normal and three with different colorectal pathologies (diverticular disease, polyps and carcinoma of the colon), were examined by MRI after colonoscopy. Subsequent to filling of the colon with a gadolinium-water mixture under MRI-monitoring, 3D-data sets of the colon were acquired in prone and supine positions over a 28 sec breathold interval. Subsequently multiplanar T{sub 1}-weighted 2D-sequences were acquired before and following i.v. administration of Gd-DTPA (0.1 mmol/kg BW). All imaging was performed in the coronal orientation. The 3D-data were interactively analysed based on various displays: Maximum intensity projection (MIP), surface shadowed display (SSD), multiplanar reconstruction (MPR), virtual colonoscopy (VC). Results: All of the colorectal pathologies could be interactively diagnosed by MPR. On MIP images some pathologies were missed. VC presented the morphology of colon haustra as well as of all endoluminally growing lesions in a manner similar to endoscopy. The colon masses showed uptake of contrast media and could thus be differentiated from air or faeces. (orig./AJ) [Deutsch] Ziel: Externe und endoskopische Identifizierung kolorektaler Pathologien mittels MRT. Material und Methoden: 5 Patienten (36-88 Jahre), zwei mit Normalbefund, drei mit verschiedenen kolorektalen pathologischen Befunden (Divertikulose, Polypen, Karzinom), wurden nach der Kolonoskopie mit der MRT untersucht. Dazu wurde das Kolon unter MR-Sichtkontrolle mit einer Gadolinium-Wasser-Mischung gefuellt und als 3D-Datensatz atemangehalten in Bauch- und Rueckenlage aufgenommen. Anschliessend wurden multiplanare, T{sub 1}-gewichtete 2D-Sequenzen vor und nach i.v. Gd-DTPA-Gabe akquiriert. Die 3D-Datensaetze wurden interaktiv unter Zuhilfenahme verschiedener Darstellungsformen analysiert: Maximale Intensitaetsprojektion (MIP), Oberflaechendarstellung

Estimation of Pulmonary Motion in Healthy Subjects and Patients with Intrathoracic Tumors Using 3D-Dynamic MRI: Initial Results

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Plathow, Christian; Schoebinger, Max; Meinzer, Heinz Peter [German Cancer Research Center, Heidelberg (Germany); Herth, Felix; Tuengerthal, Siegfried [Clinic of Thoracic Disease, Heidelberg (Germany); Kauczor, Hans Ulrich [University of Heidelberg, Heidelberg (Germany)

2009-12-15

To estimate a new technique for quantifying regional lung motion using 3D-MRI in healthy volunteers and to apply the technique in patients with intra- or extrapulmonary tumors. Intraparenchymal lung motion during a whole breathing cycle was quantified in 30 healthy volunteers using 3D-dynamic MRI (FLASH [fast low angle shot] 3D, TRICKS [time-resolved interpolated contrast kinetics]). Qualitative and quantitative vector color maps and cumulative histograms were performed using an introduced semiautomatic algorithm. An analysis of lung motion was performed and correlated with an established 2D-MRI technique for verification. As a proof of concept, the technique was applied in five patients with non-small cell lung cancer (NSCLC) and 5 patients with malignant pleural mesothelioma (MPM). The correlation between intraparenchymal lung motion of the basal lung parts and the 2D-MRI technique was significant (r = 0.89, p < 0.05). Also, the vector color maps quantitatively illustrated regional lung motion in all healthy volunteers. No differences were observed between both hemithoraces, which was verified by cumulative histograms. The patients with NSCLC showed a local lack of lung motion in the area of the tumor. In the patients with MPM, there was global diminished motion of the tumor bearing hemithorax, which improved significantly after chemotherapy (CHT) (assessed by the 2D- and 3D-techniques) (p < 0.01). Using global spirometry, an improvement could also be shown (vital capacity 2.9 {+-} 0.5 versus 3.4 L {+-} 0.6, FEV1 0.9 {+-} 0.2 versus 1.4 {+-} 0.2 L) after CHT, but this improvement was not significant. A 3D-dynamic MRI is able to quantify intraparenchymal lung motion. Local and global parenchymal pathologies can be precisely located and might be a new tool used to quantify even slight changes in lung motion (e.g. in therapy monitoring, follow-up studies or even benign lung diseases)

Pattern of mri brain abnormalities in rheumatic patients with neurological involvement: a tertiary care teaching hospital experience

International Nuclear Information System (INIS)

Parvez, K.; Arfaj, A.; Naseeb, F.; Daif, A.K.

2015-01-01

Objective: To explore the pattern of abnormalities seen on MRI in rheumatic patients with neurological manifestations and to interpret the findings in relation to clinical picture. Study Design: Descriptive study. Place and Duration of Study: Rheumatology unit, King Khalid University Hospital, Riyadh, Saudi Arabia from January 2013 to February 2014. Patients and Methods: We prospectively included rheumatic patients with neurological symptoms and signs. The clinical data were correlated with MRI findings by a team comprising of a rheumatologist, neurologist and neuro-radiologist. Data was analyzed using simple statistical analysis. Results: Fifty patients were recruited with a mean age of 36.4 ± 10.76 years (range 17-62). Among SLE patients with seizures, focal deficit and headache white matter hyperintensities were found in 9 (64.28%), 4 (50%), 4 (80%) patients respectively. Out of seven SLE patients with global dysfunction, 3 (42.85%) had brain atrophy and 2 (28.57%) normal MRI. In Behcet disease with focal deficit, 3 (75%) patients had white matter hyperintensities and 1 (25%) had brainstem involvement. In Behcet disease with headache, 2 (50%) had normal MRI, 1 (25%) brainstem hyper-intensities and 1 (25%) had subacute infarct. Two (66%) of three Primary APS patients had white matter hyperintensities while third (33%) had old infarct. Both patients of polyarteritisnodosa, had white matter hyperintensities. Out of two Wegener granulomatosis one had white matter hyperintensities and other had ischemic changes in optic nerves. The only one scleroderma patient had white matter hyperintensities. Conclusion: We found that white matter hyperintensities was the most common MRI abnormality in our study group which in most of the cases had poor clinical correlation. No distinct pattern of CNS involvement on MRI was observed in various rheumatic disorders. (author)

Volume based DCE-MRI breast cancer detection with 3D visualization system

International Nuclear Information System (INIS)

Chia, F.K.; Sim, K.S.; Chong, S.S.; Tan, S.T.; Ting, H.Y.; Abbas, S.F.; Omar, S.

2011-01-01

In this paper, a computer aided design auto probing system is presented to detect breast lesions based on Dynamic contrast enhanced Magnetic resonance imaging (DCE-MRI) images. The system is proposed in order to aid the radiologists and doctors in the interpretation of MRI breast images and enhance the detection accuracy. A series of approaches are presented to enhance the detection accuracy and refine the breast region of interest (Roil) automatically. Besides, a semi-quantitative analysis is used to segment the breast lesions from selected breast Roil and classify the detected tumour is whether benign, suspicious or malignant. The entire breast Roil including the detected tumour will display in 3D. The methodology has been applied on 104 sets of digital imaging and communications in medicine (Dico) breast MRI datasets images. The biopsy results are verified by 2 radiologists from Hospital Malaysia. The experimental results are demonstrated the proposed scheme can precisely identify breast cancer regions with 93% accuracy. (author)

Framework for 3D histologic reconstruction and fusion with in vivo MRI: Preliminary results of characterizing pulmonary inflammation in a mouse model

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Rusu, Mirabela, E-mail: mirabela.rusu@gmail.com; Wang, Haibo; Madabhushi, Anant [Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106 (United States); Golden, Thea; Gow, Andrew [Department of Pharmacology and Toxicology, Rutgers University, Piscataway, New Jersey 08854 (United States)

2015-08-15

Purpose: Pulmonary inflammation is associated with a variety of diseases. Assessing pulmonary inflammation on in vivo imaging may facilitate the early detection and treatment of lung diseases. Although routinely used in thoracic imaging, computed tomography has thus far not been compellingly shown to characterize inflammation in vivo. Alternatively, magnetic resonance imaging (MRI) is a nonionizing radiation technique to better visualize and characterize pulmonary tissue. Prior to routine adoption of MRI for early characterization of inflammation in humans, a rigorous and quantitative characterization of the utility of MRI to identify inflammation is required. Such characterization may be achieved by considering ex vivo histology as the ground truth, since it enables the definitive spatial assessment of inflammation. In this study, the authors introduce a novel framework to integrate 2D histology, ex vivo and in vivo imaging to enable the mapping of the extent of disease from ex vivo histology onto in vivo imaging, with the goal of facilitating computerized feature analysis and interrogation of disease appearance on in vivo imaging. The authors’ framework was evaluated in a preclinical preliminary study aimed to identify computer extracted features on in vivo MRI associated with chronic pulmonary inflammation. Methods: The authors’ image analytics framework first involves reconstructing the histologic volume in 3D from individual histology slices. Second, the authors map the disease ground truth onto in vivo MRI via coregistration with 3D histology using the ex vivo lung MRI as a conduit. Finally, computerized feature analysis of the disease extent is performed to identify candidate in vivo imaging signatures of disease presence and extent. Results: The authors evaluated the framework by assessing the quality of the 3D histology reconstruction and the histology—MRI fusion, in the context of an initial use case involving characterization of chronic

Framework for 3D histologic reconstruction and fusion with in vivo MRI: Preliminary results of characterizing pulmonary inflammation in a mouse model

International Nuclear Information System (INIS)

Rusu, Mirabela; Wang, Haibo; Madabhushi, Anant; Golden, Thea; Gow, Andrew

2015-01-01

Purpose: Pulmonary inflammation is associated with a variety of diseases. Assessing pulmonary inflammation on in vivo imaging may facilitate the early detection and treatment of lung diseases. Although routinely used in thoracic imaging, computed tomography has thus far not been compellingly shown to characterize inflammation in vivo. Alternatively, magnetic resonance imaging (MRI) is a nonionizing radiation technique to better visualize and characterize pulmonary tissue. Prior to routine adoption of MRI for early characterization of inflammation in humans, a rigorous and quantitative characterization of the utility of MRI to identify inflammation is required. Such characterization may be achieved by considering ex vivo histology as the ground truth, since it enables the definitive spatial assessment of inflammation. In this study, the authors introduce a novel framework to integrate 2D histology, ex vivo and in vivo imaging to enable the mapping of the extent of disease from ex vivo histology onto in vivo imaging, with the goal of facilitating computerized feature analysis and interrogation of disease appearance on in vivo imaging. The authors’ framework was evaluated in a preclinical preliminary study aimed to identify computer extracted features on in vivo MRI associated with chronic pulmonary inflammation. Methods: The authors’ image analytics framework first involves reconstructing the histologic volume in 3D from individual histology slices. Second, the authors map the disease ground truth onto in vivo MRI via coregistration with 3D histology using the ex vivo lung MRI as a conduit. Finally, computerized feature analysis of the disease extent is performed to identify candidate in vivo imaging signatures of disease presence and extent. Results: The authors evaluated the framework by assessing the quality of the 3D histology reconstruction and the histology—MRI fusion, in the context of an initial use case involving characterization of chronic

3 Tesla proton MRI for the diagnosis of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia: Initial results in comparison to HRCT

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Attenberger, U.I., E-mail: ulrike.attenberger@umm.de [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim (Germany); Morelli, J.N. [Scott and White Hospital, Texas A and M Health Sciences Center, Temple (United States); Henzler, T. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim (Germany); Buchheidt, D. [Department of Hematology and Oncology, University Medical Center Mannheim (Germany); Fink, C. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim (Germany); Department of Radiology, AKH Celle, Celle (Germany); Schoenberg, S.O.; Reichert, M. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim (Germany)

2014-01-15

Purpose: To evaluate the diagnostic accuracy of 3 Tesla proton MRI for the assessment of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia. Material and methods: In a prospective study, 3 Tesla MRI was performed in 19 febrile neutropenic patients (5 women, 14 men; mean age 61 years ± 14.2; range 23–77 years). All patients underwent high-resolution CT less than 24 h prior to MRI. The MRI protocol (Magnetom Tim Trio, Siemens) included a T2-weighted HASTE sequence (TE/TR: 49 ms/∞, slice thickness 6 mm) and a high-resolution 3D VIBE sequence with an ultra-short TE < 1 ms (TE/TR 0.8/2.9 ms, slice thickness 2 mm). The VIBE sequence was examined before and after intravenous injection of 0.1 mmol/kg gadoterate meglumine (Dotarem, Guerbet). The presence of pulmonary abnormalities, their location within the lung, and lesion type (nodules, consolidations, glass opacity areas) were analyzed by one reader and compared to the findings of HRCT, which was evaluated by a second independent radiologist who served as the reference standard. The findings were compared per lobe in each patient and rated as true positive (TP) findings if all three characteristics (presence, location, and lesion type) listed above were concordant to HRCT. Results: Pulmonary abnormalities were characterized by 3 Tesla MRI with a sensitivity of 82.3% and a specificity of 78.6%, resulting in an overall accuracy of 88% (NPV/PPV 66.7%/89.5%). In 51 lobes (19 of 19 patients), pulmonary abnormalities visualized by MR were judged to be concordant in their location and in the lesion type identified by both readers. In 22 lobes (11 of 19 patients), no abnormalities were present on either MR or HRCT (true negative). In 6 lobes (5 of 19 patients), ground glass opacity areas were detected on MRI but were not visible on HRCT (false positives). In 11 lobes (7 of 19 patients), MRI failed to detect ground glass opacity areas identified by HRCT. However, since the abnormalities were

Abnormal regional homogeneity in patients with essential tremor revealed by resting-state functional MRI.

Directory of Open Access Journals (Sweden)

Weidong Fang

Full Text Available Essential tremor (ET is one of the most common movement disorders in human adults. It can be characterized as a progressive neurological disorder of which the most recognizable feature is a tremor of the arms or hands that is apparent during voluntary movements such as eating and writing. The pathology of ET remains unclear. Resting-state fMRI (RS-fMRI, as a non-invasive imaging technique, was employed to investigate abnormalities of functional connectivity in ET in the brain. Regional homogeneity (ReHo was used as a metric of RS-fMRI to assess the local functional connectivity abnormality in ET with 20 ET patients and 20 age- and gender-matched healthy controls (HC. The ET group showed decreased ReHo in the anterior and posterior bilateral cerebellar lobes, the bilateral thalamus and the insular lobe, and increased ReHo in the bilateral prefrontal and parietal cortices, the left primary motor cortex and left supplementary motor area. The abnormal ReHo value of ET patients in the bilateral anterior cerebellar lobes and the right posterior cerebellar lobe were negatively correlated with the tremor severity score, while positively correlated with that in the left primary motor cortex. These findings suggest that the abnormality in cerebello-thalamo-cortical motor pathway is involved in tremor generation and propagation, which may be related to motor-related symptoms in ET patients. Meanwhile, the abnormality in the prefrontal and parietal regions may be associated with non-motor symptoms in ET. These findings suggest that the ReHo could be utilized for investigations of functional-pathological mechanism of ET.

A hybrid approach for fusing 4D-MRI temporal information with 3D-CT for the study of lung and lung tumor motion

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Yang, Y. X.; Van Reeth, E.; Poh, C. L., E-mail: clpoh@ntu.edu.sg [School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459 (Singapore); Teo, S.-K. [Institute of High Performance Computing, Agency for Science, Technology and Research, Singapore 138632 (Singapore); Tan, C. H. [Department of Diagnostic Radiology, Tan Tock Seng Hospital, Singapore 308433 (Singapore); Tham, I. W. K. [Department of Radiation Oncology, National University Cancer Institute, Singapore 119082 (Singapore)

2015-08-15

Purpose: Accurate visualization of lung motion is important in many clinical applications, such as radiotherapy of lung cancer. Advancement in imaging modalities [e.g., computed tomography (CT) and MRI] has allowed dynamic imaging of lung and lung tumor motion. However, each imaging modality has its advantages and disadvantages. The study presented in this paper aims at generating synthetic 4D-CT dataset for lung cancer patients by combining both continuous three-dimensional (3D) motion captured by 4D-MRI and the high spatial resolution captured by CT using the authors’ proposed approach. Methods: A novel hybrid approach based on deformable image registration (DIR) and finite element method simulation was developed to fuse a static 3D-CT volume (acquired under breath-hold) and the 3D motion information extracted from 4D-MRI dataset, creating a synthetic 4D-CT dataset. Results: The study focuses on imaging of lung and lung tumor. Comparing the synthetic 4D-CT dataset with the acquired 4D-CT dataset of six lung cancer patients based on 420 landmarks, accurate results (average error <2 mm) were achieved using the authors’ proposed approach. Their hybrid approach achieved a 40% error reduction (based on landmarks assessment) over using only DIR techniques. Conclusions: The synthetic 4D-CT dataset generated has high spatial resolution, has excellent lung details, and is able to show movement of lung and lung tumor over multiple breathing cycles.

Computational fluid dynamics simulations of blood flow regularized by 3D phase contrast MRI

DEFF Research Database (Denmark)

Rispoli, Vinicius C; Nielsen, Jon; Nayak, Krishna S

2015-01-01

BACKGROUND: Phase contrast magnetic resonance imaging (PC-MRI) is used clinically for quantitative assessment of cardiovascular flow and function, as it is capable of providing directly-measured 3D velocity maps. Alternatively, vascular flow can be estimated from model-based computation fluid dyn...

Automated segmentation of blood-flow regions in large thoracic arteries using 3D-cine PC-MRI measurements.

Science.gov (United States)

van Pelt, Roy; Nguyen, Huy; ter Haar Romeny, Bart; Vilanova, Anna

2012-03-01

Quantitative analysis of vascular blood flow, acquired by phase-contrast MRI, requires accurate segmentation of the vessel lumen. In clinical practice, 2D-cine velocity-encoded slices are inspected, and the lumen is segmented manually. However, segmentation of time-resolved volumetric blood-flow measurements is a tedious and time-consuming task requiring automation. Automated segmentation of large thoracic arteries, based solely on the 3D-cine phase-contrast MRI (PC-MRI) blood-flow data, was done. An active surface model, which is fast and topologically stable, was used. The active surface model requires an initial surface, approximating the desired segmentation. A method to generate this surface was developed based on a voxel-wise temporal maximum of blood-flow velocities. The active surface model balances forces, based on the surface structure and image features derived from the blood-flow data. The segmentation results were validated using volunteer studies, including time-resolved 3D and 2D blood-flow data. The segmented surface was intersected with a velocity-encoded PC-MRI slice, resulting in a cross-sectional contour of the lumen. These cross-sections were compared to reference contours that were manually delineated on high-resolution 2D-cine slices. The automated approach closely approximates the manual blood-flow segmentations, with error distances on the order of the voxel size. The initial surface provides a close approximation of the desired luminal geometry. This improves the convergence time of the active surface and facilitates parametrization. An active surface approach for vessel lumen segmentation was developed, suitable for quantitative analysis of 3D-cine PC-MRI blood-flow data. As opposed to prior thresholding and level-set approaches, the active surface model is topologically stable. A method to generate an initial approximate surface was developed, and various features that influence the segmentation model were evaluated. The active surface

Brain MRI signal abnormalities and right-to-left shunting in asymptomatic military divers.

Science.gov (United States)

Gempp, Emmanuel; Sbardella, Fabrice; Stephant, Eric; Constantin, Pascal; De Maistre, Sebastien; Louge, Pierre; Blatteau, Jean-Eric

2010-11-01

We conducted a controlled study to assess the prevalence of brain MRI hyperintense signals and their correlation with right-to-left shunting (RLS) in military divers. We prospectively enrolled 32 asymptomatic military divers under 41 yr of age and 32 non-diving healthy subjects matched with respect to age and vascular disease risk factors. We examined both groups with a 3-Tesla brain MRI; RLS was detected using transcranial pulsed Doppler in divers only. Hyperintense spots were observed in 43.7% of the divers and 21.8% of the control subjects. In particular, divers with significant shunting exhibited a higher prevalence of hyperintensities compared to those with slight or no RLS (75% vs. 25%, respectively). Linear trend analysis also revealed a positive correlation between focal white matter changes, determined using a validated visual rating scale and the RLS grade. Healthy military divers with a hemodynamically relevant RLS have an increased likelihood of cerebral hyperintense spots compared to age-matched normal subjects. The clinical relevance of these MRI signal abnormalities and their causal relationship with diving remain unclear.

Utility of the 3D GRE method in the female pelvic area with 3T MRI

International Nuclear Information System (INIS)

Matsushita, Hiroki; Terada, Masaki; Oosugi, Masanori; Inoue, Kazuyasu; Anma, Takeshi

2008-01-01

A high signal-to-noise ratio (SNR) can be obtained in three-Tesla (3T) MRI, and it is possible to use it to shorten imaging time and improve spatial resolution. However, reports of its disadvantages have been increasing. We attempted to describe a high-resolution evaluation image that made the best use of a decrease in specific absorption rate (SAR) and high SNR by using the LAVA (liver acquisition with volume acceleration) method, a kind of three-dimensional GRE (3D gradient echo) method that did not show the above-mentioned disadvantage in obtaining a shadow inspection of the female pelvic area with 3T MRI. A 0.8 mm isovoxel image of excellent SNR could be obtained within about one and one-half minutes by using the LAVA method as a result of the examination. Moreover, a SAR that was problematic with the 3T MR device was able to be decreased, and was useful. (author)

Comparison between target magnetic resonance imaging (MRI) in-gantry and cognitively directed transperineal or transrectal-guided prostate biopsies for Prostate Imaging-Reporting and Data System (PI-RADS) 3-5 MRI lesions.

Science.gov (United States)

Yaxley, Anna J; Yaxley, John W; Thangasamy, Isaac A; Ballard, Emma; Pokorny, Morgan R

2017-11-01

To compare the detection rates of prostate cancer (PCa) in men with Prostate Imaging-Reporting and Data System (PI-RADS) 3-5 abnormalities on 3-Tesla multiparametric (mp) magnetic resonance imaging (MRI) using in-bore MRI-guided biopsy compared with cognitively directed transperineal (cTP) biopsy and transrectal ultrasonography (cTRUS) biopsy. This was a retrospective single-centre study of consecutive men attending the private practice clinic of an experienced urologist performing MRI-guided biopsy and an experienced urologist performing cTP and cTRUS biopsy techniques for PI-RADS 3-5 lesions identified on 3-Tesla mpMRI. There were 595 target mpMRI lesions from 482 men with PI-RADS 3-5 regions of interest during 483 episodes of biopsy. The abnormal mpMRI target lesion was biopsied using the MRI-guided method for 298 biopsies, the cTP method for 248 biopsies and the cTRUS method for 49 biopsies. There were no significant differences in PCa detection among the three biopsy methods in PI-RADS 3 (48.9%, 40.0% and 44.4%, respectively), PI-RADS 4 (73.2%, 81.0% and 85.0%, respectively) or PI-RADS 5 (95.2, 92.0% and 95.0%, respectively) lesions, and there was no significant difference in detection of significant PCa among the biopsy methods in PI-RADS 3 (42.2%, 30.0% and 33.3%, respectively), PI-RADS 4 (66.8%, 66.0% and 80.0%, respectively) or PI-RADS 5 (90.5%, 89.8% and 90.0%, respectively) lesions. There were also no differences in PCa or significant PCa detection based on lesion location or size among the methods. We found no significant difference in the ability to detect PCa or significant PCa using targeted MRI-guided, cTP or cTRUS biopsy methods. Identification of an abnormal area on mpMRI appears to be more important in increasing the detection of PCa than the technique used to biopsy an MRI abnormality. © 2017 The Authors BJU International © 2017 BJU International Published by John Wiley & Sons Ltd.

Prevalence of abnormalities in knees detected by MRI in adults without knee osteoarthritis: population based observational study (Framingham Osteoarthritis Study).

Science.gov (United States)

Guermazi, Ali; Niu, Jingbo; Hayashi, Daichi; Roemer, Frank W; Englund, Martin; Neogi, Tuhina; Aliabadi, Piran; McLennan, Christine E; Felson, David T

2012-08-29

To examine use of magnetic resonance imaging (MRI) of knees with no radiographic evidence of osteoarthritis to determine the prevalence of structural lesions associated with osteoarthritis and their relation to age, sex, and obesity. Population based observational study. Community cohort in Framingham, MA, United States (Framingham osteoarthritis study). 710 people aged >50 who had no radiographic evidence of knee osteoarthritis (Kellgren-Lawrence grade 0) and who underwent MRI of the knee. Prevalence of MRI findings that are suggestive of knee osteoarthritis (osteophytes, cartilage damage, bone marrow lesions, subchondral cysts, meniscal lesions, synovitis, attrition, and ligamentous lesions) in all participants and after stratification by age, sex, body mass index (BMI), and the presence or absence of knee pain. Pain was assessed by three different questions and also by WOMAC questionnaire. Of the 710 participants, 393 (55%) were women, 660 (93%) were white, and 206 (29%) had knee pain in the past month. The mean age was 62.3 years and mean BMI was 27.9. Prevalence of "any abnormality" was 89% (631/710) overall. Osteophytes were the most common abnormality among all participants (74%, 524/710), followed by cartilage damage (69%, 492/710) and bone marrow lesions (52%, 371/710). The higher the age, the higher the prevalence of all types of abnormalities detectable by MRI. There were no significant differences in the prevalence of any of the features between BMI groups. The prevalence of at least one type of pathology ("any abnormality") was high in both painful (90-97%, depending on pain definition) and painless (86-88%) knees. MRI shows lesions in the tibiofemoral joint in most middle aged and elderly people in whom knee radiographs do not show any features of osteoarthritis, regardless of pain.

Isotropic 3D cardiac cine MRI allows efficient sparse segmentation strategies based on 3D surface reconstruction.

Science.gov (United States)

Odille, Freddy; Bustin, Aurélien; Liu, Shufang; Chen, Bailiang; Vuissoz, Pierre-André; Felblinger, Jacques; Bonnemains, Laurent

2018-05-01

Segmentation of cardiac cine MRI data is routinely used for the volumetric analysis of cardiac function. Conventionally, 2D contours are drawn on short-axis (SAX) image stacks with relatively thick slices (typically 8 mm). Here, an acquisition/reconstruction strategy is used for obtaining isotropic 3D cine datasets; reformatted slices are then used to optimize the manual segmentation workflow. Isotropic 3D cine datasets were obtained from multiple 2D cine stacks (acquired during free-breathing in SAX and long-axis (LAX) orientations) using nonrigid motion correction (cine-GRICS method) and super-resolution. Several manual segmentation strategies were then compared, including conventional SAX segmentation, LAX segmentation in three views only, and combinations of SAX and LAX slices. An implicit B-spline surface reconstruction algorithm is proposed to reconstruct the left ventricular cavity surface from the sparse set of 2D contours. All tested sparse segmentation strategies were in good agreement, with Dice scores above 0.9 despite using fewer slices (3-6 sparse slices instead of 8-10 contiguous SAX slices). When compared to independent phase-contrast flow measurements, stroke volumes computed from four or six sparse slices had slightly higher precision than conventional SAX segmentation (error standard deviation of 5.4 mL against 6.1 mL) at the cost of slightly lower accuracy (bias of -1.2 mL against 0.2 mL). Functional parameters also showed a trend to improved precision, including end-diastolic volumes, end-systolic volumes, and ejection fractions). The postprocessing workflow of 3D isotropic cardiac imaging strategies can be optimized using sparse segmentation and 3D surface reconstruction. Magn Reson Med 79:2665-2675, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

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.

CAIPIRINHA accelerated SPACE enables 10-min isotropic 3D TSE MRI of the ankle for optimized visualization of curved and oblique ligaments and tendons

Energy Technology Data Exchange (ETDEWEB)

Kalia, Vivek [University of Vermont Medical Center, Department of Radiology, Burlington, VT (United States); Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Section of Musculoskeletal Radiology, Baltimore, MD (United States); Fritz, Benjamin [University Medical Center Freiburg, Department of Radiology, Freiburg im Breisgau (Germany); Johnson, Rory [Siemens Healthcare USA, Inc, Cary, NC (United States); Gilson, Wesley D. [Siemens Healthcare USA, Inc, Baltimore, MD (United States); Raithel, Esther [Siemens Healthcare GmbH, Erlangen (Germany); Fritz, Jan [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Section of Musculoskeletal Radiology, Baltimore, MD (United States)

2017-09-15

To test the hypothesis that a fourfold CAIPIRINHA accelerated, 10-min, high-resolution, isotropic 3D TSE MRI prototype protocol of the ankle derives equal or better quality than a 20-min 2D TSE standard protocol. Following internal review board approval and informed consent, 3-Tesla MRI of the ankle was obtained in 24 asymptomatic subjects including 10-min 3D CAIPIRINHA SPACE TSE prototype and 20-min 2D TSE standard protocols. Outcome variables included image quality and visibility of anatomical structures using 5-point Likert scales. Non-parametric statistical testing was used. P values ≤0.001 were considered significant. Edge sharpness, contrast resolution, uniformity, noise, fat suppression and magic angle effects were without statistical difference on 2D and 3D TSE images (p > 0.035). Fluid was mildly brighter on intermediate-weighted 2D images (p < 0.001), whereas 3D images had substantially less partial volume, chemical shift and no pulsatile-flow artifacts (p < 0.001). Oblique and curved planar 3D images resulted in mildly-to-substantially improved visualization of joints, spring, bifurcate, syndesmotic, collateral and sinus tarsi ligaments, and tendons (p < 0.001, respectively). 3D TSE MRI with CAIPIRINHA acceleration enables high-spatial resolution oblique and curved planar MRI of the ankle and visualization of ligaments, tendons and joints equally well or better than a more time-consuming anisotropic 2D TSE MRI. (orig.)

CAIPIRINHA accelerated SPACE enables 10-min isotropic 3D TSE MRI of the ankle for optimized visualization of curved and oblique ligaments and tendons

International Nuclear Information System (INIS)

Kalia, Vivek; Fritz, Benjamin; Johnson, Rory; Gilson, Wesley D.; Raithel, Esther; Fritz, Jan

2017-01-01

To test the hypothesis that a fourfold CAIPIRINHA accelerated, 10-min, high-resolution, isotropic 3D TSE MRI prototype protocol of the ankle derives equal or better quality than a 20-min 2D TSE standard protocol. Following internal review board approval and informed consent, 3-Tesla MRI of the ankle was obtained in 24 asymptomatic subjects including 10-min 3D CAIPIRINHA SPACE TSE prototype and 20-min 2D TSE standard protocols. Outcome variables included image quality and visibility of anatomical structures using 5-point Likert scales. Non-parametric statistical testing was used. P values ≤0.001 were considered significant. Edge sharpness, contrast resolution, uniformity, noise, fat suppression and magic angle effects were without statistical difference on 2D and 3D TSE images (p > 0.035). Fluid was mildly brighter on intermediate-weighted 2D images (p < 0.001), whereas 3D images had substantially less partial volume, chemical shift and no pulsatile-flow artifacts (p < 0.001). Oblique and curved planar 3D images resulted in mildly-to-substantially improved visualization of joints, spring, bifurcate, syndesmotic, collateral and sinus tarsi ligaments, and tendons (p < 0.001, respectively). 3D TSE MRI with CAIPIRINHA acceleration enables high-spatial resolution oblique and curved planar MRI of the ankle and visualization of ligaments, tendons and joints equally well or better than a more time-consuming anisotropic 2D TSE MRI. (orig.)

Brain MRI findings of spontaneous intracranial hypotension

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Park, Won Kyu; Byun, Woo Mok; Cho, Jae Ho; Cho Kil Ho; Hwang, Mi Soo; Park, Bok Hwan [Yeungnam Univ. College of Medicine, Taegu (Korea, Republic of); Joo, Yang Gu [Keimyoung Univ. College of Medicine, Taegu (Korea, Republic of); Lee, Sang Jin [Soonchunhyang Univ. College of Medicine, Seoul (Korea, Republic of)

1997-09-01

To evaluate brain MRI findings of spontaneous intracranial hypotension. A retrospective review of MRI findings was conducted on six patients with clinically proven spontaneous intracranial hypotension; no patient had a history of previous spinal puncture. Follow-up MRI was available in two patients, and to detect CSF leakage, radio-nuclide cisternography(n=3D5), myelography(n=3D1), and MR myelography(n=3D1) were performed. On contrast-enhanced T1WI, diffuse dural enhancement was seen in all cases, subdural hematoma or hygroma was seen in four cases, pituitary gland prominence in four, dural sinus dilatation in four, downward displacement of the cerebellar tonsil in two, downward displacement of the iter in one, and suprasellar and prepontine cistern effacement in two. In no patient was abnormal CSF leakage found. Although dural enhancement, as seen on MRI, is not specific, diffuse enhancement of the dura mater accompanied by subdural hematoma, hygroma, pituitary gland prominence, dural sinus dilatation, downward displacement of the cerebellar tonsil, or suprasellar and prepontine cistern effacement can strongly suggest intracranial hypotension.=20.

Respiratory motion-resolved, self-gated 4D-MRI using Rotating Cartesian K-space (ROCK): Initial clinical experience on an MRI-guided radiotherapy system.

Science.gov (United States)

Han, Fei; Zhou, Ziwu; Du, Dongsu; Gao, Yu; Rashid, Shams; Cao, Minsong; Shaverdian, Narek; Hegde, John V; Steinberg, Michael; Lee, Percy; Raldow, Ann; Low, Daniel A; Sheng, Ke; Yang, Yingli; Hu, Peng

2018-06-01

To optimize and evaluate the respiratory motion-resolved, self-gated 4D-MRI using Rotating Cartesian K-space (ROCK-4D-MRI) method in a 0.35 T MRI-guided radiotherapy (MRgRT) system. The study included seven patients with abdominal tumors treated on the MRgRT system. ROCK-4D-MRI and 2D-CINE, was performed immediately after one of the treatment fractions. Motion quantification based on 4D-MRI was compared with those based on 2D-CINE. The image quality of 4D-MRI was evaluated against 4D-CT. The gross tumor volumes (GTV) were defined based on individual respiratory phases of both 4D-MRI and 4D-CT and compared for their variability over the respiratory cycle. The motion measurements based on 4D-MRI matched well with 2D-CINE, with differences of 1.04 ± 0.52 mm in the superior-inferior and 0.54 ± 0.21 mm in the anterior-posterior directions. The image quality scores of 4D-MRI were significantly higher than 4D-CT, with better tumor contrast (3.29 ± 0.76 vs. 1.86 ± 0.90) and less motion artifacts (3.57 ± 0.53 vs. 2.29 ± 0.95). The GTVs were more consistent in 4D-MRI than in 4D-CT, with significantly smaller GTV variability (9.31 ± 4.58% vs. 34.27 ± 23.33%). Our study demonstrated the clinical feasibility of using the ROCK-4D-MRI to acquire high quality, respiratory motion-resolved 4D-MRI in a low-field MRgRT system. The 4D-MRI image could provide accurate dynamic information for radiotherapy treatment planning. Copyright © 2018 Elsevier B.V. All rights reserved.

Evaluation of COPD's diaphragm motion extracted from 4D-MRI

Science.gov (United States)

Swastika, Windra; Masuda, Yoshitada; Kawata, Naoko; Matsumoto, Koji; Suzuki, Toshio; Iesato, Ken; Tada, Yuji; Sugiura, Toshihiko; Tanabe, Nobuhiro; Tatsumi, Koichiro; Ohnishi, Takashi; Haneishi, Hideaki

2015-03-01

We have developed a method called intersection profile method to construct a 4D-MRI (3D+time) from time-series of 2D-MRI. The basic idea is to find the best matching of the intersection profile from the time series of 2D-MRI in sagittal plane (navigator slice) and time series of 2D-MRI in coronal plane (data slice). In this study, we use 4D-MRI to semiautomatically extract the right diaphragm motion of 16 subjects (8 healthy subjects and 8 COPD patients). The diaphragm motion is then evaluated quantitatively by calculating the displacement of each subjects and normalized it. We also generate phase-length map to view and locate paradoxical motion of the COPD patients. The quantitative results of the normalized displacement shows that COPD patients tend to have smaller displacement compared to healthy subjects. The average normalized displacement of total 8 COPD patients is 9.4mm and the average of normalized displacement of 8 healthy volunteers is 15.3mm. The generated phase-length maps show that not all of the COPD patients have paradoxical motion, however if it has paradoxical motion, the phase-length map is able to locate where does it occur.

Sub-Millimeter T2 Weighted fMRI at 7 T: Comparison of 3D-GRASE and 2D SE-EPI

Directory of Open Access Journals (Sweden)

Valentin G. Kemper

2015-05-01

Full Text Available Functional magnetic resonance imaging (fMRI allows studying human brain function non-invasively up to the spatial resolution of cortical columns and layers. Most fMRI acquisitions rely on the blood oxygenation level dependent (BOLD contrast employing T2* weighted 2D multi-slice echo-planar imaging (EPI. At ultra-high magnetic field (i.e. 7 T and above, it has been shown experimentally and by simulation, that T2 weighted acquisitions yield a signal that is spatially more specific to the site of neuronal activity at the cost of functional sensitivity. This study compared two T2 weighted imaging sequences, inner-volume 3D Gradient-and-Spin-Echo (3D-GRASE and 2D Spin-Echo EPI (SE-EPI, with evaluation of their imaging point-spread function, functional specificity, and functional sensitivity at sub-millimeter resolution. Simulations and measurements of the imaging point-spread function revealed that the strongest anisotropic blurring in 3D-GRASE (along the second phase-encoding direction was about 60 % higher than the strongest anisotropic blurring in 2D SE-EPI (along the phase-encoding direction In a visual paradigm, the BOLD sensitivity of 3D-GRASE was found to be superior due to its higher temporal signal-to-noise ratio. High resolution cortical depth profiles suggested that the contrast mechanisms are similar between the two sequences, however, 2D SE-EPI had a higher surface bias owing to the higher T2* contribution of the longer in-plane EPI echo-train for full field of view compared to the reduced field of view of zoomed 3D-GRASE.

MRI-based 3D pelvic autonomous innervation: a first step towards image-guided pelvic surgery

Energy Technology Data Exchange (ETDEWEB)

Bertrand, M.M. [University Montpellier I, Laboratory of Experimental Anatomy Faculty of Medicine Montpellier-Nimes, Montpellier (France); Macri, F.; Beregi, J.P. [Nimes University Hospital, University Montpellier 1, Radiology Department, Nimes (France); Mazars, R.; Prudhomme, M. [University Montpellier I, Laboratory of Experimental Anatomy Faculty of Medicine Montpellier-Nimes, Montpellier (France); Nimes University Hospital, University Montpellier 1, Digestive Surgery Department, Nimes (France); Droupy, S. [Nimes University Hospital, University Montpellier 1, Urology-Andrology Department, Nimes (France)

2014-08-15

To analyse pelvic autonomous innervation with magnetic resonance imaging (MRI) in comparison with anatomical macroscopic dissection on cadavers. Pelvic MRI was performed in eight adult human cadavers (five men and three women) using a total of four sequences each: T1, T1 fat saturation, T2, diffusion weighed. Images were analysed with segmentation software in order to extract nervous tissue. Key height points of the pelvis autonomous innervation were located in every specimen. Standardised pelvis dissections were then performed. Distances between the same key points and the three anatomical references forming a coordinate system were measured on MRIs and dissections. Concordance (Lin's concordance correlation coefficient) between MRI and dissection was calculated. MRI acquisition allowed an adequate visualization of the autonomous innervation. Comparison between 3D MRI images and dissection showed concordant pictures. The statistical analysis showed a mean difference of less than 1 cm between MRI and dissection measures and a correct concordance correlation coefficient on at least two coordinates for each point. Our acquisition and post-processing method demonstrated that MRI is suitable for detection of autonomous pelvic innervations and can offer a preoperative nerve cartography. (orig.)

Individualised 3D printed vaginal template for MRI guided brachytherapy in locally advanced cervical cancer

DEFF Research Database (Denmark)

Lindegaard, Jacob Christian; Lænsø Madsen, Mads; Hansen, Anders Traberg

2016-01-01

Intracavitary–interstitial applicators for MRI guided brachytherapy are becoming increasingly important in locally advanced cervical cancer. The 3D printing technology enables a versatile method for obtaining a high degree of individualisation of the implant. Our clinical workflow is presented...

Less Is More: Efficacy of Rapid 3D-T2 SPACE in ED Patients with Acute Atypical Low Back Pain.

Science.gov (United States)

Koontz, Nicholas A; Wiggins, Richard H; Mills, Megan K; McLaughlin, Michael S; Pigman, Elaine C; Anzai, Yoshimi; Shah, Lubdha M

2017-08-01

Emergency department (ED) patients with acute low back pain (LBP) may present with ambiguous clinical findings that pose diagnostic challenges to exclude cauda equina syndrome (CES). As a proof of concept, we aimed to determine the efficacy of a rapid lumbar spine (LS) magnetic resonance imaging (MRI) screening protocol consisting of a single 3D-T2 SPACE FS (3D-T2 Sampling Perfection with Application optimized Contrasts using different flip angle Evolution fat saturated) sequence relative to conventional LS MRI to exclude emergently treatable pathologies in this complex patient population. LS MRI protocol including a sagittal 3D-T2 SPACE FS pulse sequence was added to the routine for ED patients presenting with acute atypical LBP over a 12-month period. Imaging findings were categorically scored on the 3D-T2 SPACE FS sequence and separately on the reference standard conventional LS MRI sequences. Patients' symptoms were obtained from review of the electronic medical record. Descriptive test statistics were performed. Of the 206 ED patients who obtained MRI for acute atypical LBP, 118 (43.3 ± 13.5 years of age; 61 female) were included. Specific pathologies detected on reference standard conventional MRI included disc herniation (n = 30), acute fracture (n = 3), synovial cyst (n = 3), epidural hematoma (n = 2), cerebrospinal fluid leak (n = 1), and leptomeningeal metastases (n = 1), and on multiple occasions these pathologies resulted in nerve root impingement (n = 36), severe spinal canal stenosis (n = 13), cord/conus compression (n = 2), and cord signal abnormality (n = 2). The 3D-T2 SPACE FS sequence was an effective screen for fracture (sensitivity [sens] = 100%, specificity [spec] = 100%), cord signal abnormality (sens = 100%, spec = 99%), and severe spinal canal stenosis (sens = 100%, spec = 96%), and identified cord compression not seen on reference standard. Motion artifact was not seen on

Diagnosis of spinal dural arteriovenous fistula using 3D T2-weighted imaging

Energy Technology Data Exchange (ETDEWEB)

Kralik, Stephen F.; Murph, Daniel; Mehta, Peter; O' Neill, Darren P. [Indiana University School of Medicine, Department of Radiology and Imaging Sciences, Indianapolis, IN (United States)

2017-10-15

To evaluate spinal MRIs without and with 3D T2W imaging among patients without and with spinal dural arteriovenous fistula (SDAVF) confirmed by spinal digital subtraction angiography (DSA). A retrospective case-control study was performed among patients without and with SDAVF who had both spinal MRIs and gold standard spinal DSA. Two neuroradiologists independently reviewed spinal MRIs that were performed with either sagittal T2W turbo spin echo (2D group) or sagittal 3D T2W sampling perfection with application-optimized contrasts using different flip-angle evolutions (SPACE) (3D group) and documented the presence or absence of SDAVF. Using spinal DSA diagnosis as a gold standard, the sensitivity, specificity, and interobserver agreement for the 2D-group and 3D-group MRI diagnosis were calculated. The 2D group consisted of 21 patients and the 3D group consisted of 16 patients. For both radiologists, the 2D group demonstrated a sensitivity of 100% and specificity of 100%. Interobserver agreement in the 2D group was perfect (k = 1.0). For both radiologists, the 3D group demonstrated sensitivity of 100.0% and specificity of 92.3%. Interobserver agreement in the 3D group was perfect (k = 1.0). While flow voids were considered more conspicuous, spinal cord signal abnormality was considered less conspicuous with 3D T2W SPACE compared with conventional 2D STIR sequence. 3D T2W SPACE should be used in conjunction with 2D T2W sequences to more accurately detect abnormal cord signal and determine when perimedullary flow voids are pathologically abnormal for the radiologic diagnosis of SDAVF. (orig.)

Incremental value of PET and MRI in the evaluation of cardiovascular abnormalities.

Science.gov (United States)

Chalian, Hamid; O'Donnell, James K; Bolen, Michael; Rajiah, Prabhakar

2016-08-01

The cardiovascular system is affected by a wide range of pathological processes, including neoplastic, inflammatory, ischemic, and congenital aetiology. Magnetic resonance imaging (MRI) and positron emission tomography (PET) are state-of-the-art imaging modalities used in the evaluation of these cardiovascular disorders. MRI has good spatial and temporal resolutions, tissue characterization and multi-planar imaging/reconstruction capabilities, which makes it useful in the evaluation of cardiac morphology, ventricular and valvar function, disease characterization, and evaluation of myocardial viability. FDG-PET provides valuable information on the metabolic activity of the cardiovascular diseases, including ischemia, inflammation, and neoplasm. MRI and FDG-PET can provide complementary information on the evaluation of several cardiovascular disorders. For example, in cardiac masses, FDG-PET provides the metabolic information for indeterminate cardiac masses. MRI can be used for localizing and characterizing abnormal hypermetabolic foci identified incidentally on PET scan and also for local staging. A recent advance in imaging technology has been the development of integrated PET/MRI systems that utilize the advantages of PET and MRI in a single examination. The goal of this manuscript is to provide a comprehensive review on the incremental value of PET and MRI in the evaluation of cardiovascular diseases. • MRI has good spatial and temporal resolutions, tissue characterization, and multi-planar reconstruction • FDG-PET provides valuable information on the metabolic activity of cardiovascular disorders • PET and MRI provide complementary information on the evaluation of cardiovascular disorders.

MRI findings in 100 epileptic children

Energy Technology Data Exchange (ETDEWEB)

Suzukawa, Junko; Sugimoto, Tateo; Araki, Atsushi (Kansai Medical School, Moriguchi, Osaka (Japan)) (and others)

1993-02-01

Findings of magnetic resonance imaging (MRI) of the brain were retrospectively reviewed in 100 consecutive pediatric patients with epilepsy in relation to the type of epilepsy and prognosis. There were 65 boys and 35 girls, ranging in age from 3 months to 25 years. Among 100 patients, 67 (a total of 102 lesions) showed abnormal findings on MRI. Morphological abnormalities, including ventricular enlargement, atrophy and malformation, were seen in 54 patients. Periventricular (n=14), frontal (n=3), temporal (n=8) and occipital (n=7) areas were of high signal intensity on T2-weighted images. According to the type of epilepsy, MRI abnormality was seen in 34 (61%) of 56 patients with partial seizures and 33 (76%) of 44 patients with generalized seizures. When associated with cerebral palsy and mental retardation, the incidence of MRI abnormality was high. There was no sigificant correlation between MRI findings and prognosis. (N.K.).

MRI findings in 100 epileptic children

International Nuclear Information System (INIS)

Suzukawa, Junko; Sugimoto, Tateo; Araki, Atsushi

1993-01-01

Findings of magnetic resonance imaging (MRI) of the brain were retrospectively reviewed in 100 consecutive pediatric patients with epilepsy in relation to the type of epilepsy and prognosis. There were 65 boys and 35 girls, ranging in age from 3 months to 25 years. Among 100 patients, 67 (a total of 102 lesions) showed abnormal findings on MRI. Morphological abnormalities, including ventricular enlargement, atrophy and malformation, were seen in 54 patients. Periventricular (n=14), frontal (n=3), temporal (n=8) and occipital (n=7) areas were of high signal intensity on T2-weighted images. According to the type of epilepsy, MRI abnormality was seen in 34 (61%) of 56 patients with partial seizures and 33 (76%) of 44 patients with generalized seizures. When associated with cerebral palsy and mental retardation, the incidence of MRI abnormality was high. There was no sigificant correlation between MRI findings and prognosis. (N.K.)

3D MRI Modeling of Thin and Spatially Complex Soft Tissue Structures without Shrinkage: Lamprey Myosepta as an Example.

Science.gov (United States)

Wood, Bradley M; Jia, Guang; Carmichael, Owen; McKlveen, Kevin; Homberger, Dominique G

2018-05-12

3D imaging techniques enable the non-destructive analysis and modeling of complex structures. Among these, MRI exhibits good soft tissue contrast, but is currently less commonly used for non-clinical research than x-ray CT, even though the latter requires contrast-staining that shrinks and distorts soft tissues. When the objective is the creation of a realistic and complete 3D model of soft tissue structures, MRI data are more demanding to acquire and visualize and require extensive post-processing because they comprise non-cubic voxels with dimensions that represent a trade-off between tissue contrast and image resolution. Therefore, thin soft tissue structures with complex spatial configurations are not always visible in a single MRI dataset, so that standard segmentation techniques are not sufficient for their complete visualization. By using the example of the thin and spatially complex connective tissue myosepta in lampreys, we developed a workflow protocol for the selection of the appropriate parameters for the acquisition of MRI data and for the visualization and 3D modeling of soft tissue structures. This protocol includes a novel recursive segmentation technique for supplementing missing data in one dataset with data from another dataset to produce realistic and complete 3D models. Such 3D models are needed for the modeling of dynamic processes, such as the biomechanics of fish locomotion. However, our methodology is applicable to the visualization of any thin soft tissue structures with complex spatial configurations, such as fasciae, aponeuroses, and small blood vessels and nerves, for clinical research and the further exploration of tensegrity. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

Quantification of Diaphragm Mechanics in Pompe Disease Using Dynamic 3D MRI.

Directory of Open Access Journals (Sweden)

Katja Mogalle

Full Text Available Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification of respiratory muscle involvement is necessary to initiate treatment in time and possibly prevent irreversible damage. In this paper we investigate the suitability of dynamic MR imaging in combination with state-of-the-art image analysis methods to assess respiratory muscle weakness.The proposed methodology relies on image registration and lung surface extraction to quantify lung kinematics during breathing. This allows for the extraction of geometry and motion features of the lung that characterize the independent contribution of the diaphragm and the thoracic muscles to the respiratory cycle.Results in 16 3D+t MRI scans (10 Pompe patients and 6 controls of a slow expiratory maneuver show that kinematic analysis from dynamic 3D images reveals important additional information about diaphragm mechanics and respiratory muscle involvement when compared to conventional pulmonary function tests. Pompe patients with severely reduced pulmonary function showed severe diaphragm weakness presented by minimal motion of the diaphragm. In patients with moderately reduced pulmonary function, cranial displacement of posterior diaphragm parts was reduced and the diaphragm dome was oriented more horizontally at full inspiration compared to healthy controls.Dynamic 3D MRI provides data for analyzing the contribution of both diaphragm and thoracic muscles independently. The proposed image analysis method has the potential to detect less severe diaphragm weakness and could thus be used to determine the optimal start of treatment in adult patients with Pompe disease in prospect of increased treatment response.

MRI Findings in 77 Children with Non-Syndromic Autistic Disorder

Science.gov (United States)

Boddaert, Nathalie; Zilbovicius, Mônica; Philipe, Anne; Robel, Laurence; Bourgeois, Marie; Barthélemy, Catherine; Seidenwurm, David; Meresse, Isabelle; Laurier, Laurence; Desguerre, Isabelle; Bahi-Buisson, Nadia; Brunelle, Francis; Munnich, Arnold; Samson, Yves; Mouren, Marie-Christine; Chabane, Nadia

2009-01-01

Background The clinical relevance of MR scanning in children with autism is still an open question and must be considered in light of the evolution of this technology. MRI was judged to be of insufficient value to be included in the standard clinical evaluation of autism according to the guidelines of the American Academy of Neurology and Child Neurology Society in 2000 [1]. However, this statement was based on results obtained from small samples of patients and, more importantly, included mostly insufficient MRI sequences. Our main objective was to evaluate the prevalence of brain abnormalities in a large group of children with a non-syndromic autistic disorder (AD) using T1, T2 and FLAIR MRI sequences. Methodology MRI inspection of 77 children and adolescents with non-syndromic AD (mean age 7.4±3.6) was performed. All met the DSM-IV and ADI –R criteria for autism. Based on recommended clinical and biological screenings, we excluded patients with infectious, metabolic or genetic diseases, seizures or any other neurological symptoms. Identical MRI inspections of 77 children (mean age 7.0±4.2) without AD, developmental or neurological disorders were also performed. All MRIs were acquired with a 1.5-T Signa GE (3-D T1-FSPGR, T2, FLAIR coronal and axial sequences). Two neuroradiologists independently inspected cortical and sub-cortical regions. MRIs were reported to be normal, abnormal or uninterpretable. Principal Findings MRIs were judged as uninterpretable in 10% (8/77) of the cases. In 48% of the children (33/69 patients), abnormalities were reported. Three predominant abnormalities were observed, including white matter signal abnormalities (19/69), major dilated Virchow–Robin spaces (12/69) and temporal lobe abnormalities (20/69). In all, 52% of the MRIs were interpreted as normal (36/69 patients). Conclusions An unexpectedly high rate of MRI abnormalities was found in the first large series of clinical MRI investigations in non-syndromic autism. These

[Dynamic study of the female levator ani muscle using MRI 3D vectorial modeling].

Science.gov (United States)

Delmas, Vincent; Ami, Olivier; Iba-Zizen, Marie-Thérèse

2010-06-01

The levator ani muscle has a major role in the female pelvic floor, and is involved in the pathophysiology of pelvic prolapse and stress urinary incontinence. We conducted an anatomical and morphological study of this muscle using dynamic 3D vectorial reconstruction MRI, in order to analyze the contraction of two major components of the levator ani: the iliococcygeus and pubococcygeus. Three volunteer healthy continent nulliparous women aged from 19 to 22 underwent dynamic pelvic MRI. Coronal T2-weighted pelvic images were obtained in the supine position, at rest, holding back, and during Valsalva stress effort. 3D vectorial models were reconstructed by manual segmentation of the source images, and were set up on bony anatomic marks. Iliococcygeus and pubococcygeus volumes were measured in the three positions. Volumetrics, displacement and dynamic morphing changes were analyzed with 3D vectorial animation software. The urogenital hiatus extended more holding back (mean +4.31 mm) than on effort (mean +2.78 mm). The iliococcygeus lowered (mean -3.95 mm) and deviated outward (mean +3.01 mm). The basic tone of the iliococcygeus muscle gives it a dome shape, and its reflex contraction against abdominal strain ensures anal and urinary continence The levator ani is more than a pelvic diaphragm: it is a truly dynamic pelvic floor. Its points of support on the stiff osseous frame allow it to retain the pelvic organs. The levator ani muscle seems to prevent anal prolapse during stress strain.

Virtual cardiotomy based on 3-D MRI for preoperative planning in congenital heart disease

International Nuclear Information System (INIS)

Soerensen, Thomas Sangild; Beerbaum, Philipp; Razavi, Reza; Greil, Gerald Franz; Mosegaard, Jesper; Rasmusson, Allan; Schaeffter, Tobias; Austin, Conal

2008-01-01

Patient-specific preoperative planning in complex congenital heart disease may be greatly facilitated by virtual cardiotomy. Surgeons can perform an unlimited number of surgical incisions on a virtual 3-D reconstruction to evaluate the feasibility of different surgical strategies. To quantitatively evaluate the quality of the underlying imaging data and the accuracy of the corresponding segmentation, and to qualitatively evaluate the feasibility of virtual cardiotomy. A whole-heart MRI sequence was applied in 42 children with congenital heart disease (age 3±3 years, weight 13±9 kg, heart rate 96± 21 bpm). Image quality was graded 1-4 (diagnostic image quality ≥2) by two independent blinded observers. In patients with diagnostic image quality the segmentation quality was also graded 1-4 (4 no discrepancies, 1 misleading error). The average image quality score was 2.7 - sufficient for virtual reconstruction in 35 of 38 patients (92%) older than 1 month. Segmentation time was 59±10 min (average quality score 3.5). Virtual cardiotomy was performed in 19 patients. Accurate virtual reconstructions of patient-specific cardiac anatomy can be produced in less than 1 h from 3-D MRI. The presented work thus introduces a new, clinically feasible noninvasive technique for improved preoperative planning in complex cases of congenital heart disease. (orig.)

Age-related changes in aortic 3D blood flow velocities and wall shear stress: Implications for the identification of altered hemodynamics in patients with aortic valve disease

NARCIS (Netherlands)

van Ooij, Pim; Garcia, Julio; Potters, Wouter V.; Malaisrie, S. Chris; Collins, Jeremy D.; Carr, James C.; Markl, Michael; Barker, Alex J.

2016-01-01

To investigate age-related changes in peak systolic aortic 3D velocity and wall shear stress (WSS) in healthy controls and to investigate the importance of age-matching for 3D mapping of abnormal aortic hemodynamics in bicuspid aortic valve disease (BAV). 4D flow MRI (fields strengths = 1.5-3T;

Quantitative 3D ultrashort time-to-echo (UTE) MRI and micro-CT (μCT) evaluation of the temporomandibular joint (TMJ) condylar morphology

Energy Technology Data Exchange (ETDEWEB)

Geiger, Daniel [Sapienza University of Rome, Department of Radiological, Oncological and Pathological Sciences, Rome (Italy); Bae, Won C.; Statum, Sheronda; Du, Jiang; Chung, Christine B. [University of California-San Diego, Department of Radiology, San Diego, CA (United States)

2014-01-15

Temporomandibular dysfunction involves osteoarthritis of the TMJ, including degeneration and morphologic changes of the mandibular condyle. The purpose of this study was to determine the accuracy of novel 3D-UTE MRI versus micro-CT (μCT) for quantitative evaluation of mandibular condyle morphology. Nine TMJ condyle specimens were harvested from cadavers (2 M, 3 F; age 85 ± 10 years, mean ± SD). 3D-UTE MRI (TR = 50 ms, TE = 0.05 ms, 104-μm isotropic-voxel) was performed using a 3-T MR scanner and μCT (18-μm isotropic-voxel) was also performed. MR datasets were spatially registered with a μCT dataset. Two observers segmented bony contours of the condyles. Fibrocartilage was segmented on the MR dataset. Using a custom program, bone and fibrocartilage surface coordinates, Gaussian curvature, volume of segmented regions, and fibrocartilage thickness were determined for quantitative evaluation of joint morphology. Agreement between techniques (MRI vs. μCT) and observers (MRI vs. MRI) for Gaussian curvature, mean curvature, and segmented volume of the bone were determined using intraclass correlation coefficient (ICC) analysis. Between MRI and μCT, the average deviation of surface coordinates was 0.19 ± 0.15 mm, slightly higher than the spatial resolution of MRI. Average deviation of the Gaussian curvature and volume of segmented regions, from MRI to μCT, was 5.7 ± 6.5 % and 6.6 ± 6.2 %, respectively. ICC coefficients (MRI vs. μCT) for Gaussian curvature, mean curvature, and segmented volumes were 0.892, 0.893, and 0.972, respectively. Between observers (MRI vs. MRI), the ICC coefficients were 0.998, 0.999, and 0.997, respectively. Fibrocartilage thickness was 0.55 ± 0.11 mm, as previously described in the literature for grossly normal TMJ samples. 3D-UTE MR quantitative evaluation of TMJ condyle morphology ex-vivo, including surface, curvature, and segmented volume, shows high correlation against μCT and between observers. In addition, UTE MRI allows

Audiovisual biofeedback improves image quality and reduces scan time for respiratory-gated 3D MRI

Science.gov (United States)

Lee, D.; Greer, P. B.; Arm, J.; Keall, P.; Kim, T.

2014-03-01

The purpose of this study was to test the hypothesis that audiovisual (AV) biofeedback can improve image quality and reduce scan time for respiratory-gated 3D thoracic MRI. For five healthy human subjects respiratory motion guidance in MR scans was provided using an AV biofeedback system, utilizing real-time respiratory motion signals. To investigate the improvement of respiratory-gated 3D MR images between free breathing (FB) and AV biofeedback (AV), each subject underwent two imaging sessions. Respiratory-related motion artifacts and imaging time were qualitatively evaluated in addition to the reproducibility of external (abdominal) motion. In the results, 3D MR images in AV biofeedback showed more anatomic information such as a clear distinction of diaphragm, lung lobes and sharper organ boundaries. The scan time was reduced from 401±215 s in FB to 334±94 s in AV (p-value 0.36). The root mean square variation of the displacement and period of the abdominal motion was reduced from 0.4±0.22 cm and 2.8±2.5 s in FB to 0.1±0.15 cm and 0.9±1.3 s in AV (p-value of displacement audiovisual biofeedback improves image quality and reduces scan time for respiratory-gated 3D MRI. These results suggest that AV biofeedback has the potential to be a useful motion management tool in medical imaging and radiation therapy procedures.

Multi-feature-based plaque characterization in ex vivo MRI trained by registration to 3D histology

DEFF Research Database (Denmark)

Engelen, Arna van; Niessen, Wiro J.; Klein, Stefan

2012-01-01

. The ground truth for fibrous, necrotic and calcified tissue was provided by histology and micro-CT in 12 carotid plaque specimens. Semi-automatic registration of a 3D stack of histological slices and micro-CT images to MRI allowed for 3D rotations and inplane deformations of histology. By basing voxelwise...

Effect of Task-Correlated Physiological Fluctuations and Motion in 2D and 3D Echo-Planar Imaging in a Higher Cognitive Level fMRI Paradigm.

Science.gov (United States)

Ladstein, Jarle; Evensmoen, Hallvard R; Håberg, Asta K; Kristoffersen, Anders; Goa, Pål E

2016-01-01

To compare 2D and 3D echo-planar imaging (EPI) in a higher cognitive level fMRI paradigm. In particular, to study the link between the presence of task-correlated physiological fluctuations and motion and the fMRI contrast estimates from either 2D EPI or 3D EPI datasets, with and without adding nuisance regressors to the model. A signal model in the presence of partly task-correlated fluctuations is derived, and predictions for contrast estimates with and without nuisance regressors are made. Thirty-one healthy volunteers were scanned using 2D EPI and 3D EPI during a virtual environmental learning paradigm. In a subgroup of 7 subjects, heart rate and respiration were logged, and the correlation with the paradigm was evaluated. FMRI analysis was performed using models with and without nuisance regressors. Differences in the mean contrast estimates were investigated by analysis-of-variance using Subject, Sequence, Day, and Run as factors. The distributions of group level contrast estimates were compared. Partially task-correlated fluctuations in respiration, heart rate and motion were observed. Statistically significant differences were found in the mean contrast estimates between the 2D EPI and 3D EPI when using a model without nuisance regressors. The inclusion of nuisance regressors for cardiorespiratory effects and motion reduced the difference to a statistically non-significant level. Furthermore, the contrast estimate values shifted more when including nuisance regressors for 3D EPI compared to 2D EPI. The results are consistent with 3D EPI having a higher sensitivity to fluctuations compared to 2D EPI. In the presence partially task-correlated physiological fluctuations or motion, proper correction is necessary to get expectation correct contrast estimates when using 3D EPI. As such task-correlated physiological fluctuations or motion is difficult to avoid in paradigms exploring higher cognitive functions, 2D EPI seems to be the preferred choice for higher

The superiority of 3D-CISS sequence in displaying the cisternal segment of facial, vestibulocochlear nerves and their abnormal changes

Energy Technology Data Exchange (ETDEWEB)

Liang Changhu, E-mail: tigerlch@163.co [Shandong University, Shandong Medical Imaging Research Institute, CT Room, 324, Jingwu Road, Jinan, Shandong (China); Zhang Bin, E-mail: liangchangbo.student@sina.co [Liao Cheng City People' s Hospital, Dongchang Road, Liaocheng, Shandong (China); Wu Lebin, E-mail: Lebinwu518@163.co [Shandong University, Shandong Medical Imaging Research Institute, CT Room, 324, Jingwu Road, Jinan, Shandong (China); Du Yinglin, E-mail: duyinglinzhuo@sohu.co [Shandong Provincial Center for Disease Control and Prevention, Public Health Institute, 72, Jingshi Road, Jinan, Shandong (China); Wang Ximing, E-mail: wxminmg369@163.co [Shandong University, Shandong Medical Imaging Research Institute, CT Room, 324, Jingwu Road, Jinan, Shandong (China); Liu Cheng, E-mail: cacab2a@126.co [Shandong University, Shandong Medical Imaging Research Institute, CT Room, 324, Jingwu Road, Jinan, Shandong (China); Yu Fuhua, E-mail: changhu1970@163.co [Weifang Medical College, 7166, West Road Baotong Weifang, Shandong (China)

2010-06-15

Objective: To select the best imaging method for clinical otologic patients through evaluating 3D constructive interference of steady state (CISS) image quality in visualizing the facial, vestibulocochlear nerves (CN:VII-VIII) and their abnormal changes. Methods: The CN:VII-VIII as well as inner ear structures in 48 volunteers were examined using 3D-CISS and 3D turbo spin echo (TSE) sequences respectively, and displayed to the full at the reformatted and maximum intensity projection (MIP) images. The nerve identification and image quality were graded for the CN:VII-VIII as well as inner ear structures. Statistical analysis was performed using the Wilcoxin test, p < 0.05 was considered significant. In addition, 8 patients with abnormality in facial or vestibulocochlear nerves were also examined using 3D-CISS sequence. Results: The identification rates for the cisternal segment of facial, vestibulocochlear nerves and corresponding membranous labyrinth were 100%. Abnormal changes of the facial or vestibulocochlear nerves were clearly shown in 8 patients, among them 1 was caused by bilateral acoustic neurinoma, 1 by cholesteatoma at cerebellopontine angle, 1 by arachnoid cyst, 1 by neurovascular adhesion, 4 by neurovascular compression. Conclusion: With 3D-CISS sequence the fine structure of the CN:VII-VIII and corresponding membranous labyrinth can be clearly demonstrated; lesions at the site of cerebellopontine angle can also be found easily.

Reduced GABAA receptor density contralateral to a potentially epileptogenic MRI abnormality in a patient with complex partial seizures

International Nuclear Information System (INIS)

Kuwert, T.; Stodieck, S.R.G.; Puskas, C.; Diehl, B.; Puskas, Z.; Schuierer, G.; Vollet, B.; Schober, O.

1996-01-01

Imaging cerebral GABA A receptor density (GRD) with single-photon emission tomography (SPET) and iodine-123 iomazenil is highly accurate in lateralizing epileptogenic foci in patients with complex partial seizures of temporal origin. Limited knowledge exists on how iomazenil SPET compares with magnetic resonance imaging (MRI) in this regard. We present a patient with complex partial seizures in whom MRI had identified an arachnoid cyst anterior to the tip of the left temporal lobe. Contralaterally to this structural abnormality, interictal electroencephalography (EEG) performed after sleep deprivation disclosed an intermittent frontotemporal dysrhythmic focus with slow and sharp waves. On iomazenil SPET images GRD was significantly reduced in the right temporal lobe and thus contralaterally to the MRI abnormality, but ipsilaterally to the pathological EEG findings. These data suggest that iomazenil SPET may significantly contribute to the presurgical evaluation of epileptic patients even when MRI identifies potentialy epileptogenic structural lesions. (orig.)

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

OpenAIRE

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

2015-01-01

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

Large deformation diffeomorphic metric mapping registration of reconstructed 3D histological section images and in vivo MR images

Directory of Open Access Journals (Sweden)

Can Ceritoglu

2010-05-01

Full Text Available Our current understanding of neuroanatomical abnormalities in neuropsychiatric diseases is based largely on magnetic resonance imaging (MRI and post mortem histological analyses of the brain. Further advances in elucidating altered brain structure in these human conditions might emerge from combining MRI and histological methods. We propose a multistage method for registering 3D volumes reconstructed from histological sections to corresponding in vivo MRI volumes from the same subjects: (1 manual segmentation of white matter (WM, gray matter (GM and cerebrospinal fluid (CSF compartments in histological sections, (2 alignment of consecutive histological sections using 2D rigid transformation to construct a 3D histological image volume from the aligned sections, (3 registration of reconstructed 3D histological volumes to the corresponding 3D MRI volumes using 3D affine transformation, (4 intensity normalization of images via histogram matching and (5 registration of the volumes via intensity based Large Deformation Diffeomorphic Metric (LDDMM image matching algorithm. Here we demonstrate the utility of our method in the transfer of cytoarchitectonic information from histological sections to identify regions of interest in MRI scans of nine adult macaque brains for morphometric analyses. LDDMM improved the accuracy of the registration via decreased distances between GM/CSF surfaces after LDDMM (0.39±0.13 mm compared to distances after affine registration (0.76±0.41 mm. Similarly, WM/GM distances decreased to 0.28±0.16 mm after LDDMM compared to 0.54±0.39 mm after affine registration. The multistage registration method may find broad application for mapping histologically based information, e.g., receptor distributions, gene expression, onto MRI volumes.

Loss of neuronal integrity: a cause of hypometabolism in patients with traumatic brain injury without MRI abnormality in the chronic stage

International Nuclear Information System (INIS)

Shiga, Tohru; Matsuyama, Tetsuaki; Kageyama, Hiroyuki; Kohno, Tomoya; Tamaki, Nagara; Ikoma, Katsunori; Isoyama, Hirotaka; Katoh, Chietsugu; Kuge, Yuji; Terae, Satoshi

2006-01-01

Traumatic brain injury (TBI) causes brain dysfunction in many patients. However, some patients have severe brain dysfunction but display no abnormalities on magnetic resonance imaging (MRI). There have been some reports of hypometabolism even in such patients. The purpose of this study was to investigate the relationship between metabolic abnormality and loss of neuronal integrity in TBI patients with some symptoms but without MRI abnormalities. The study population comprised ten patients with TBI and ten normal volunteers. All of the patients were examined at least 1 year after the injury. 15 O-labelled gas PET and [ 11 C]flumazenil (FMZ) positron emission tomography (PET) were carried out. The cerebral metabolic rate of oxygen (CMRO 2 ) and binding potential (BP) images of FMZ were calculated. Axial T2WI, T2*WI and FLAIR images were obtained. Coronal images were added in some cases. All of the patients had normal MRI findings, and all showed areas with abnormally low CMRO 2 . Low uptake on BP images was observed in six patients (60%). No lesions that showed low uptake on BP images were without low CMRO 2 . On the other hand, there were 14 lesions with low CMRO 2 but without BP abnormalities. These results indicate that there are metabolic abnormalities in TBI patients with some symptoms after brain injury but without abnormalities on MRI. Some of the hypometabolic lesions showed low BP, indicating a loss of neuronal integrity. Thus, FMZ PET may have potential to distinguish hypometabolism caused by neuronal loss from that caused by other factors. (orig.)

7T MRI in focal epilepsy with unrevealing conventional field strength imaging.

Science.gov (United States)

De Ciantis, Alessio; Barba, Carmen; Tassi, Laura; Cosottini, Mirco; Tosetti, Michela; Costagli, Mauro; Bramerio, Manuela; Bartolini, Emanuele; Biagi, Laura; Cossu, Massimo; Pelliccia, Veronica; Symms, Mark R; Guerrini, Renzo

2016-03-01

To assess the diagnostic yield of 7T magnetic resonance imaging (MRI) in detecting and characterizing structural lesions in patients with intractable focal epilepsy and unrevealing conventional (1.5 or 3T) MRI. We conducted an observational clinical imaging study on 21 patients (17 adults and 4 children) with intractable focal epilepsy, exhibiting clinical and electroencephalographic features consistent with a single seizure-onset zone (SOZ) and unrevealing conventional MRI. Patients were enrolled at two tertiary epilepsy surgery centers and imaged at 7T, including whole brain (three-dimensional [3D] T1 -weighted [T1W] fast-spoiled gradient echo (FSPGR), 3D susceptibility-weighted angiography [SWAN], 3D fluid-attenuated inversion recovery [FLAIR]) and targeted imaging (2D T2*-weighted dual-echo gradient-recalled echo [GRE] and 2D gray-white matter tissue border enhancement [TBE] fast spin echo inversion recovery [FSE-IR]). MRI studies at 1.5 or 3T deemed unrevealing at the referral center were reviewed by three experts in epilepsy imaging. Reviewers were provided information regarding the suspected localization of the SOZ. The same team subsequently reviewed 7T images. Agreement in imaging interpretation was reached through consensus-based discussions based on visual identification of structural abnormalities and their likely correlation with clinical and electrographic data. 7T MRI revealed structural lesions in 6 (29%) of 21 patients. The diagnostic gain in detection was obtained using GRE and FLAIR images. Four of the six patients with abnormal 7T underwent epilepsy surgery. Histopathology revealed focal cortical dysplasia (FCD) in all. In the remaining 15 patients (71%), 7T MRI remained unrevealing; 4 of the patients underwent epilepsy surgery and histopathologic evaluation revealed gliosis. 7T MRI improves detection of epileptogenic FCD that is not visible at conventional field strengths. A dedicated protocol including whole brain FLAIR and GRE images at 7T

Audiovisual biofeedback improves image quality and reduces scan time for respiratory-gated 3D MRI

International Nuclear Information System (INIS)

Lee, D; Keall, P; Kim, T; Greer, P B; Arm, J

2014-01-01

The purpose of this study was to test the hypothesis that audiovisual (AV) biofeedback can improve image quality and reduce scan time for respiratory-gated 3D thoracic MRI. For five healthy human subjects respiratory motion guidance in MR scans was provided using an AV biofeedback system, utilizing real-time respiratory motion signals. To investigate the improvement of respiratory-gated 3D MR images between free breathing (FB) and AV biofeedback (AV), each subject underwent two imaging sessions. Respiratory-related motion artifacts and imaging time were qualitatively evaluated in addition to the reproducibility of external (abdominal) motion. In the results, 3D MR images in AV biofeedback showed more anatomic information such as a clear distinction of diaphragm, lung lobes and sharper organ boundaries. The scan time was reduced from 401±215 s in FB to 334±94 s in AV (p-value 0.36). The root mean square variation of the displacement and period of the abdominal motion was reduced from 0.4±0.22 cm and 2.8±2.5 s in FB to 0.1±0.15 cm and 0.9±1.3 s in AV (p-value of displacement <0.01 and p-value of period 0.12). This study demonstrated that audiovisual biofeedback improves image quality and reduces scan time for respiratory-gated 3D MRI. These results suggest that AV biofeedback has the potential to be a useful motion management tool in medical imaging and radiation therapy procedures.

TU-AB-BRA-07: Distortion-Free 3D Diffusion MRI On An MRI-Guided Radiotherapy System for Longitudinal Tumor Response Assessment

International Nuclear Information System (INIS)

Gao, Y; Yang, Y; Rangwala, N; Cao, M; Low, D; Hu, P

2016-01-01

Purpose: To develop a reliable, 3D distortion-free diffusion MRI technique for longitudinal tumor response assessment and MRI-guided adaptive radiotherapy(RT). Methods: A diffusion prepared 3D turbo spin echo readout (DP-TSE) sequence was developed and compared with the conventional diffusion-weighted single-shot echo-planar-imaging (DW-ssEPI) sequence in a commercially available diffusion phantom, and one head-and-neck and one brain cancer patient on an MRI-guided RT system (ViewRay). In phantom study, the geometric fidelity was quantified as the ratio between the left-right (RL) and anterior-posterior (AP) dimension. Ten slices were measured on DP-TSE, DW-ssEPI and standard TSE images where the later was used as the geometric reference. ADC accuracy was verified at both 0°C (reference ADC available) and room temperature with a range of diffusivity between 0.35 and 2.0*10"−"3mm"2/s. The ADC reproducibility was assessed based on 8 room-temperature measurements on 6 different days. In the pilot single-slice in-vivo study, CT images were used as the geometric reference, and ADC maps from both diffusion sequences were compared. Results: Distortion and susceptive-related artifact were severe in DW-ssEPI, with significantly lower RL/AP ratio (0.9579±0.0163) than DP-TSE (0.9990±0.0031) and TSE (0.9995±0.0031). ADCs from the two diffusion sequences both matched well with the vendor-provided values at 0°C; however DW-ssEPI fails to provide accurate ADC for high diffusivity vials at room temperature due to high noise level (10 times higher than DP-TSE). The DP-TSE sequence had excellent ADC reproducibility with <4% ADC variation among 8 separate measurements. In patient study, DP-TSE exhibited substantially improved geometric reliability. ROI analysis in ADC maps generated from DP-TSE and DW-ssEPI showed <5% difference where high b-value images were excluded from the latter approach due to excessive noise level. Conclusion: A diffusion MRI sequence with excellent

TU-AB-BRA-07: Distortion-Free 3D Diffusion MRI On An MRI-Guided Radiotherapy System for Longitudinal Tumor Response Assessment

Energy Technology Data Exchange (ETDEWEB)

Gao, Y; Yang, Y; Rangwala, N; Cao, M; Low, D; Hu, P [UCLA School of Medicine, Los Angeles, CA (United States)

2016-06-15

Purpose: To develop a reliable, 3D distortion-free diffusion MRI technique for longitudinal tumor response assessment and MRI-guided adaptive radiotherapy(RT). Methods: A diffusion prepared 3D turbo spin echo readout (DP-TSE) sequence was developed and compared with the conventional diffusion-weighted single-shot echo-planar-imaging (DW-ssEPI) sequence in a commercially available diffusion phantom, and one head-and-neck and one brain cancer patient on an MRI-guided RT system (ViewRay). In phantom study, the geometric fidelity was quantified as the ratio between the left-right (RL) and anterior-posterior (AP) dimension. Ten slices were measured on DP-TSE, DW-ssEPI and standard TSE images where the later was used as the geometric reference. ADC accuracy was verified at both 0°C (reference ADC available) and room temperature with a range of diffusivity between 0.35 and 2.0*10{sup −3}mm{sup 2}/s. The ADC reproducibility was assessed based on 8 room-temperature measurements on 6 different days. In the pilot single-slice in-vivo study, CT images were used as the geometric reference, and ADC maps from both diffusion sequences were compared. Results: Distortion and susceptive-related artifact were severe in DW-ssEPI, with significantly lower RL/AP ratio (0.9579±0.0163) than DP-TSE (0.9990±0.0031) and TSE (0.9995±0.0031). ADCs from the two diffusion sequences both matched well with the vendor-provided values at 0°C; however DW-ssEPI fails to provide accurate ADC for high diffusivity vials at room temperature due to high noise level (10 times higher than DP-TSE). The DP-TSE sequence had excellent ADC reproducibility with <4% ADC variation among 8 separate measurements. In patient study, DP-TSE exhibited substantially improved geometric reliability. ROI analysis in ADC maps generated from DP-TSE and DW-ssEPI showed <5% difference where high b-value images were excluded from the latter approach due to excessive noise level. Conclusion: A diffusion MRI sequence with

3D T2-weighted imaging to shorten multiparametric prostate MRI protocols.

Science.gov (United States)

Polanec, Stephan H; Lazar, Mathias; Wengert, Georg J; Bickel, Hubert; Spick, Claudio; Susani, Martin; Shariat, Shahrokh; Clauser, Paola; Baltzer, Pascal A T

2018-04-01

To determine whether 3D acquisitions provide equivalent image quality, lesion delineation quality and PI-RADS v2 performance compared to 2D acquisitions in T2-weighted imaging of the prostate at 3 T. This IRB-approved, prospective study included 150 consecutive patients (mean age 63.7 years, 35-84 years; mean PSA 7.2 ng/ml, 0.4-31.1 ng/ml). Two uroradiologists (R1, R2) independently rated image quality and lesion delineation quality using a five-point ordinal scale and assigned a PI-RADS score for 2D and 3D T2-weighted image data sets. Data were compared using visual grading characteristics (VGC) and receiver operating characteristics (ROC)/area under the curve (AUC) analysis. Image quality was similarly good to excellent for 2D T2w (mean score R1, 4.3 ± 0.81; R2, 4.7 ± 0.83) and 3D T2w (mean score R1, 4.3 ± 0.82; R2, 4.7 ± 0.69), p = 0.269. Lesion delineation was rated good to excellent for 2D (mean score R1, 4.16 ± 0.81; R2, 4.19 ± 0.92) and 3D T2w (R1, 4.19 ± 0.94; R2, 4.27 ± 0.94) without significant differences (p = 0.785). ROC analysis showed an equivalent performance for 2D (AUC 0.580-0.623) and 3D (AUC 0.576-0.629) T2w (p > 0.05, respectively). Three-dimensional acquisitions demonstrated equivalent image and lesion delineation quality, and PI-RADS v2 performance, compared to 2D in T2-weighted imaging of the prostate. Three-dimensional T2-weighted imaging could be used to considerably shorten prostate MRI protocols in clinical practice. • 3D shows equivalent image quality and lesion delineation compared to 2D T2w. • 3D T2w and 2D T2w image acquisition demonstrated comparable diagnostic performance. • Using a single 3D T2w acquisition may shorten the protocol by 40%. • Combined with short DCE, multiparametric protocols of 10 min are feasible.

Study of cervical cord injury without radiological abnormality using MRI at injury

International Nuclear Information System (INIS)

Park, Jin-Soo; Ei, Terumi; Uchida, Yoko; Kodai, Yujiro; Yasumatsu, Hideo; Yoshino, Kazutaka; Hirakawa, Takashi.

1994-01-01

This study was undertaken, using MRI at the time of injury, to examine cervical cord injury without radiological abnormality. The subjects were 30 patients (24 men and 6 women) seen during the 4-year period 1989-1993, who ranged in age from 31 to 83 years (an average age of 62.8 years). Of these patients, 10 had a slightly irregular alignment of the vertebral body on plain X-rays. These 10 patients were examined using MRI early after sustaining trauma (within 24 hours in 9 and 48 hours in one). As a result, spinal cord was seen as isointensity on T1-weighted images and hyperintensity on T2-weighted images, corresponding to irregular alignment. These findings suggest that reduction of a dislocation may transiently occur due to patient transfer or natural elasticity, as plain X-rays indicated no evidence of bone abnormalities. Thus injuries like dislocations may have occurred at the time of trauma, and structural changes of the vertebral body may be responsible for the occurrence of cervical spinal cord. Spinal cord injuries, even if not evidenced on plain X-rays, should not be categorized as non-osseous injuries. (N.K.)

Neuropsychological deficits and morphological MRI brain scan abnormalities in apparently health non-encephalopathic patients with cirrhosis

International Nuclear Information System (INIS)

Moore, J.W.; De Lacey, G.; Dunk, A.A.; Sinclair, T.S.; Mowat, M.A.G.; Brunt, P.W.; Deans, H.; Crawford, J.R.; Besson, J.A.O.

1989-01-01

By means of psychometric testing, we have determined the frequency of latent hepatic encephalopathy in a group of 19 cirrhotics with no clinical evidence of encephalopathy. Magnetic resonance imaging (MRI) of the brain was performed in order to determine whether morphological cerebral abnormalities were associated with latent encephalopathy. Nineteen age and educationally matched patient with normal liver function acted as controls. Significant differences (P < 0.05) between cirrhotics and controls were found in tests of short-term visual memory and speed of reaction to light (cirrhotics 326 ] 132 ms vs. controls 225 ] 36 ms), sound (cirrhotics 361 ] 152 ms vs. controls 236 ] 52 ms) and choice (cirrhotics 651 ] 190 ms vs. controls 406 ] 101 ms) stimuli (all values mean ] S.D.). Reitan trail test performance, however, was similar in both groups. ( Trail A: cirrhotics 43 ] 19 s vs. controls 35 ] 13 s; Trail B: cirrhotics 105 ] 66 s vs. controls 93 ] 36 s.) In patients with cirrhosis, MRI revealed statistically significant increases in the maximum fissure width of right frontal sulci, light and left parietal sulci, inter-hemispheric fissure width and in bicaudafe index. These changes, indicating cerebral atrophy, were largely confined to alcoholics. There was poor correlation between measurements of cerebral morphology and neuropsychological performance, only 10% of associations achieving statistical significance. (author). 2 refs.; 3 figs.; 5 tabs

Magnetic resonance imaging of neonatal brain. Assessment of normal and abnormal findings

International Nuclear Information System (INIS)

Hasegawa, Koh; Kadono, Naoko; Kawase, Shohji; Kihara, Minako; Matsuo, Yasutaka; Yoshioka, Hiroshi; Kinugasa, Akihiko; Sawada, Tadashi

1994-01-01

To establish the normal MRI appearance of the neonatal brain, magnetic resonance imaging (MRI) was performed on 124 neonates who admitted to our neonatal intensive care unit. Degree of myelination, ventricular size, width of the extracerebral space and focal lesion in the brain were evaluated to investigate the relationship between MRI findings of neonatal brain and the neurological prognosis. 85 neonates underwent MRI both at neonatal period and at the corrected age of one year. The change of abnormal MRI findings was evaluated. 19 neonates had abnormal neurological outcome on subsequent examinations. Delayed myelination, ventriculomegaly and large extracerebral space were seen in 13, 7 and 9 neonates respectively. 4, 3 and 5 neonates out of them showed abnormal neurological prognosis respectively. Of the 19 neonates with focal lesion in MRI, 2 had parenchymal hematoma in the brain, 2 had subdural hematoma, 5 had chronic hematoma following subependymal hemorrhage, 6 had cystic formation following subependymal hemorrhage, 2 had subcortical leukomalacia, one had periventricular leukomalacia and one had cyst in the parenchyma of cerebellum. 4 neonates of 19 with focal lesion in MRI showed abnormal development. Of the neonates who had abnormal neurological prognosis, 7 neonates showed no abnormal finding in MRI at neonatal period. 3 of them had mild mental retardation. MRI shows promise in the neonatal period. It facilitates recognition of abnormalities of neonatal brain and may be used to predict abnormal neurologic outcome. However physiological change in the brain of neonates, especially of premature neonates, should be considered on interpreting these findings. Awareness of developmental features should help to minimize misinterpretation of normal changes in the neonatal brain. (author)

Magnetic resonance imaging of neonatal brain. Assessment of normal and abnormal findings

Energy Technology Data Exchange (ETDEWEB)

Hasegawa, Koh; Kadono, Naoko; Kawase, Shohji; Kihara, Minako; Matsuo, Yasutaka; Yoshioka, Hiroshi; Kinugasa, Akihiko; Sawada, Tadashi (Kyoto Prefectural Univ. of Medicine (Japan))

1994-11-01

To establish the normal MRI appearance of the neonatal brain, magnetic resonance imaging (MRI) was performed on 124 neonates who admitted to our neonatal intensive care unit. Degree of myelination, ventricular size, width of the extracerebral space and focal lesion in the brain were evaluated to investigate the relationship between MRI findings of neonatal brain and the neurological prognosis. 85 neonates underwent MRI both at neonatal period and at the corrected age of one year. The change of abnormal MRI findings was evaluated. 19 neonates had abnormal neurological outcome on subsequent examinations. Delayed myelination, ventriculomegaly and large extracerebral space were seen in 13, 7 and 9 neonates respectively. 4, 3 and 5 neonates out of them showed abnormal neurological prognosis respectively. Of the 19 neonates with focal lesion in MRI, 2 had parenchymal hematoma in the brain, 2 had subdural hematoma, 5 had chronic hematoma following subependymal hemorrhage, 6 had cystic formation following subependymal hemorrhage, 2 had subcortical leukomalacia, one had periventricular leukomalacia and one had cyst in the parenchyma of cerebellum. 4 neonates of 19 with focal lesion in MRI showed abnormal development. Of the neonates who had abnormal neurological prognosis, 7 neonates showed no abnormal finding in MRI at neonatal period. 3 of them had mild mental retardation. MRI shows promise in the neonatal period. It facilitates recognition of abnormalities of neonatal brain and may be used to predict abnormal neurologic outcome. However physiological change in the brain of neonates, especially of premature neonates, should be considered on interpreting these findings. Awareness of developmental features should help to minimize misinterpretation of normal changes in the neonatal brain. (author).

Fast CSF MRI for brain segmentation; Cross-validation by comparison with 3D T1-based brain segmentation methods

DEFF Research Database (Denmark)

van der Kleij, Lisa A.; de Bresser, Jeroen; Hendrikse, Jeroen

2018-01-01

ObjectiveIn previous work we have developed a fast sequence that focusses on cerebrospinal fluid (CSF) based on the long T-2 of CSF. By processing the data obtained with this CSF MRI sequence, brain parenchymal volume (BPV) and intracranial volume (ICV) can be automatically obtained. The aim...... of this study was to assess the precision of the BPV and ICV measurements of the CSF MRI sequence and to validate the CSF MRI sequence by comparison with 3D T-1-based brain segmentation methods.Materials and methodsTen healthy volunteers (2 females; median age 28 years) were scanned (3T MRI) twice......cc) and CSF HR (5 +/- 5/4 +/- 2cc) were comparable to FSL HR (9 +/- 11/19 +/- 23cc), FSL LR (7 +/- 4,6 +/- 5cc),FreeSurfer HR (5 +/- 3/14 +/- 8cc), FreeSurfer LR (9 +/- 8,12 +/- 10cc), and SPM HR (5 +/- 3/4 +/- 7cc), and SPM LR (5 +/- 4,5 +/- 3cc). The correlation between the measured volumes...

Anatomical Origin of Abnormal Somatosensory-Evoked Potential (SEP) in Adolescent Idiopathic Scoliosis With Different Curve Severity and Correlation With Cerebellar Tonsillar Level Determined by MRI.

Science.gov (United States)

Chau, Wai Wang; Chu, Winnie C W; Lam, Tsz Ping; Ng, Bobby K W; Fu, Linda L K; Cheng, Jack C Y

2016-05-01

A prospective cohort study. The aim of this study was to compare the somatosensory-evoked potential (SEP) findings of adolescent idiopathic scoliosis (AIS) subjects of different curve severity with age- and gender-matched controls and to evaluate any correlation between the site of the SEP abnormality with cerebellar tonsillar level measured by magnetic resonance imaging (MRI). Our previous studies showed that a higher percentage of SEP abnormality and cerebellar tonsillar ectopia was present in AIS patients than in normal controls. However, the relationship between the anatomical site of the neurophysiological abnormality and the severity in AIS patients has not been defined. SEP measurement was conducted on 91 Chinese AIS girls with major right thoracic curve of different curve severity (mild, moderate, severe) and 49 matched normal controls. Waveform characteristics (latency and amplitude) were compared among groups. Specific location of SEP abnormality was identified from tibial to cortical levels. Cerebellar tonsillar ectopia was defined by the previously established reference line between basion and opisthion on MRI. Significant prolonged P37 latency was found on the right side between severe AIS patients and normal controls, while increased inter-side P37 latency difference was found between severe versus moderate, and severe versus normal controls. Cerebellar tonsillar ectopia was detected in 27.3% of severe group, 5.8% to 6.7% in mild and moderate group, but none in normal controls. Abnormal SEP occurred superior to C5 region in all surgical (severe) patients, of whom 58% had cerebellar tonsillar ectopia. AIS patients showed significant prolonged latency and increased latency difference on the side of major curvature. The incidence of SEP abnormality increased with curve severity and occurred above the C5 level. The findings suggested that there was a subgroup of progressive AIS with subclinical neurophysiological dysfunction, associated with underlying

MRI of the popliteofibular ligament: isotropic 3D WE-DESS versus coronal oblique fat-suppressed T2W MRI

International Nuclear Information System (INIS)

Rajeswaran, G.; Lee, J.C.; Healy, J.C.

2007-01-01

The objective was to compare isotropic 3D water excitation double-echo steady state (WE-DESS) MRI with coronal oblique fat-suppressed T2-weighted (FS T2W) images in the identification of the popliteofibular ligament (PFL). A prospective analysis of 122 consecutive knee MRIs was performed in patients referred for knee pain from the orthopaedic clinic. In addition to the standard knee sequences, isotropic WE-DESS volume acquisition through the whole knee and coronal oblique FS T2W fast spin echo sequences through the posterolateral corner were obtained. The presence of the popliteus and biceps femoris tendons, lateral collateral and PFL was documented. Anterior cruciate ligament injury was present in 33 cases and these were excluded from the study because of the risk of associated PFL injury, leaving a total of 89 cases. Of the 42 patients in whom arthroscopic evaluation was subsequently obtained, none were found to have an injury to the PFL. The lateral collateral ligament, biceps femoris and popliteus tendon were identified in all cases on all sequences. The PFL was seen in 81 (91.0%; 95% CI 85.1-97.0%) patients using the WE-DESS sequence and 63 (70.8%; 95% CI 61.3-80.2%) patients using the coronal oblique FS T2W sequence, a statistically significant difference (p < 0.00005). Isotropic 3D WE-DESS MRI significantly enhances our ability to identify the popliteofibular ligament compared with coronal oblique fat-suppressed T2-weighted images. (orig.)

MRI for early diagnosis of avascular necrosis of the femoral head

International Nuclear Information System (INIS)

Kokubo, Takashi; Takatori, Yoshio; Kamogawa, Morihide; Ninomiya, Setsuo; Yoshikawa, Kohki; Itai, Yuji; Iio, Masahiro; Mitamura, Tadayuki

1988-01-01

Magnetic resonance imaging (MRI) was performed in forty patients on long-term oral steroid therapy for early detection of avascular necrosis (AN) of the femoral head. In 13 patients, AN was diagnosed in the unilateral femoral head from abnormal plain radiographs while the contralateral femoral head was normal radiographically. In the other 27 patients, radiographs were normal. A total of 67 femoral heads with normal radiographs is studied in this paper. In 36 of 67 femoral heads (54 %), MRI demonstrated abnormal low intensity area. The abnormal findings on MRI were divided into five patterns: whole type (type A), peripheral type (type B), ring or band type (type C), small change type (type D) and distal type (type E). Type A, B, C, D and E were found in 2, 11, 5, 16 and 2 femoral heads, respectively. In cases to be followed up over 6 months, AN was manifested radiographically in 4 femoral heads of 5 in type C and in one of 14 in type D. Meanwhile, in 6 of 41 femoral heads examined (15 %), bone scintigrams was abnormal. Followed-up study over 6 months revealed that AN was manifested radiographically in one femoral head of 6 with abnormal scintigram. However, in 4 of 30 with normal scintigram, AN was manifested subsequently. MRI was a better diagnostic modality for early AN. Ring or band-like low intensity (type C) on MRI was considered to be characteristic pattern of early AN. (author)

MRI for early diagnosis of avascular necrosis of the femoral head

Energy Technology Data Exchange (ETDEWEB)

Kokubo, Takashi; Takatori, Yoshio; Kamogawa, Morihide; Ninomiya, Setsuo; Yoshikawa, Kohki; Itai, Yuji; Iio, Masahiro; Mitamura, Tadayuki

1988-09-01

Magnetic resonance imaging (MRI) was performed in forty patients on long-term oral steroid therapy for early detection of avascular necrosis (AN) of the femoral head. In 13 patients, AN was diagnosed in the unilateral femoral head from abnormal plain radiographs while the contralateral femoral head was normal radiographically. In the other 27 patients, radiographs were normal. A total of 67 femoral heads with normal radiographs is studied in this paper. In 36 of 67 femoral heads (54 %), MRI demonstrated abnormal low intensity area. The abnormal findings on MRI were divided into five patterns: whole type (type A), peripheral type (type B), ring or band type (type C), small change type (type D) and distal type (type E). Type A, B, C, D and E were found in 2, 11, 5, 16 and 2 femoral heads, respectively. In cases to be followed up over 6 months, AN was manifested radiographically in 4 femoral heads of 5 in type C and in one of 14 in type D. Meanwhile, in 6 of 41 femoral heads examined (15 %), bone scintigrams was abnormal. Followed-up study over 6 months revealed that AN was manifested radiographically in one femoral head of 6 with abnormal scintigram. However, in 4 of 30 with normal scintigram, AN was manifested subsequently. MRI was a better diagnostic modality for early AN. Ring or band-like low intensity (type C) on MRI was considered to be characteristic pattern of early AN.

Middle and Inferior Temporal Gyrus Gray Matter Volume Abnormalities in First-Episode Schizophrenia: An MRI Study

OpenAIRE

Kuroki, Noriomi; Shenton, Martha Elizabeth; Salisbury, Dean; Hirayasu, Yoshio; Onitsuka, Toshiaki; Ersner-Hershfield, Hal; Yurgelun-Todd, Deborah; Kikinis, Ron; Jolesz, Ferenc A.; McCarley, Robert William

2006-01-01

Objective: Magnetic resonance imaging (MRI) studies of schizophrenia reveal temporal lobe structural brain abnormalities in the superior temporal gyrus and the amygdala-hippocampal complex. However, the middle and inferior temporal gyri have received little investigation, especially in first-episode schizophrenia. Method: High-spatial-resolution MRI was used to measure gray matter volume in the inferior, middle, and superior temporal gyri in 20 patients with first-episode schizophrenia, 20 pa...

Diagnosing CADASIL using MRI: evidence from families with known mutations of Notch 3 gene

International Nuclear Information System (INIS)

Chawda, S.J.; Lange, R.P.J. de; St-Clair, D.; Hourihan, M.D.; Halpin, S.F.S.

2000-01-01

Clinical data and MRI findings are presented on 18 subjects from two families with neuropathologically confirmed CADASIL. DNA analysis revealed mutations in exon 4 of Notch 3 gene in both families. All family members with mutations in Notch 3 gene had extensive abnormalities on MRI, principally lesions in the white matter of the frontal lobes and in the external capsules. Of several family members in whom a diagnosis of CADASIL was suspected on the basis of minor symptoms, one had MRI changes consistent with CADASIL; none of these cases carried a mutation in the Notch 3 gene. MRI and clinical features that may alert the radiologist to the diagnosis of CADASIL are reviewed. However, a wide differential diagnosis exists for the MRI appearances of CADASIL, including multiple sclerosis and small-vessel disease secondary to hypertension. The definitive diagnosis cannot be made on MRI alone and requires additional evidence, where available, from a positive family history and by screening DNA for mutations of Notch 3 gene. (orig.)

3D pulmonary perfusion MRI and MR angiography of pulmonary embolism in pigs after a single injection of a blood pool MR contrast agent

International Nuclear Information System (INIS)

Fink, Christian; Ley, Sebastian; Puderbach, Michael; Plathow, Christian; Kauczor, Hans-Ulrich; Bock, Michael

2004-01-01

The purpose of this study was to assess the feasibility of contrast-enhanced 3D perfusion MRI and MR angiography (MRA) of pulmonary embolism (PE) in pigs using a single injection of the blood pool contrast Gadomer. PE was induced in five domestic pigs by injection of autologous blood thrombi. Contrast-enhanced first-pass 3D perfusion MRI (TE/TR/FA: 1.0 ms/2.2 ms/40 ; voxel size: 1.3 x 2.5 x 4.0 mm 3 ; TA: 1.8 s per data set) and high-resolution 3D MRA (TE/TR/FA: 1.4 ms/3.4 ms/40 ; voxel size: 0.8 x 1.0 x 1.6 mm 3 ) was performed during and after a single injection of 0.1 mmol/kg body weight of Gadomer. Image data were compared to pre-embolism Gd-DTPA-enhanced MRI and post-embolism thin-section multislice CT (n=2). SNR measurements were performed in the pulmonary arteries and lung. One animal died after induction of PE. In all other animals, perfusion MRI and MRA could be acquired after a single injection of Gadomer. At perfusion MRI, PE could be detected by typical wedge-shaped perfusion defects. While the visualization of central PE at MRA correlated well with the CT, peripheral PE were only visualized by CT. Gadomer achieved a higher peak SNR of the lungs compared to Gd-DTPA (21±8 vs. 13±3). Contrast-enhanced 3D perfusion MRI and MRA of PE can be combined using a single injection of the blood pool contrast agent Gadomer. (orig.)

SU-E-J-192: Verification of 4D-MRI Internal Target Volume Using Cine MRI

Energy Technology Data Exchange (ETDEWEB)

Lafata, K; Czito, B; Palta, M; Bashir, M; Yin, F; Cai, J [Duke University Medical Center, Durham, NC (United States)

2014-06-01

Purpose: To investigate the accuracy of 4D-MRI in determining the Internal Target Volume (ITV) used in radiation oncology treatment planning of liver cancers. Cine MRI is used as the standard baseline in establishing the feasibility and accuracy of 4D-MRI tumor motion within the liver. Methods: IRB approval was obtained for this retrospective study. Analysis was performed on MR images from four patients receiving external beam radiation therapy for liver cancer at our institution. Eligible patients received both Cine and 4D-MRI scans before treatment. Cine images were acquired sagittally in real time at a slice bisecting the tumor, while 4D images were acquired volumetrically. Cine MR DICOM headers were manipulated such that each respiratory frame was assigned a unique slice location. This approach permitted the treatment planning system (Eclipse, Varian Medical Systems) to recognize a complete respiratory cycle as a “volume”, where the gross tumor was contoured temporally. Software was developed to calculate the union of all frame contours in the structure set, resulting in the corresponding plane of the ITV projecting through the middle of the tumor, defined as the Internal Target Area (ITA). This was repeated for 4D-MRI, at the corresponding slice location, allowing a direct comparison of ITAs obtained from each modality. Results: Four patients have been analyzed. ITAs contoured from 4D-MRI correlate with contours from Cine MRI. The mean error of 4D values relative to Cine values is 7.67 +/− 2.55 %. No single ITA contoured from 4D-MRI demonstrated more than 10.5 % error compared to its Cine MRI counterpart. Conclusion: Motion management is a significant aspect of treatment planning within dynamic environments such as the liver, where diaphragmatic and cardiac activity influence plan accuracy. This small pilot study suggests that 4D-MRI based ITA measurements agree with Cine MRI based measurements, an important step towards clinical implementation. NIH 1R21

SU-E-J-192: Verification of 4D-MRI Internal Target Volume Using Cine MRI

International Nuclear Information System (INIS)

Lafata, K; Czito, B; Palta, M; Bashir, M; Yin, F; Cai, J

2014-01-01

Purpose: To investigate the accuracy of 4D-MRI in determining the Internal Target Volume (ITV) used in radiation oncology treatment planning of liver cancers. Cine MRI is used as the standard baseline in establishing the feasibility and accuracy of 4D-MRI tumor motion within the liver. Methods: IRB approval was obtained for this retrospective study. Analysis was performed on MR images from four patients receiving external beam radiation therapy for liver cancer at our institution. Eligible patients received both Cine and 4D-MRI scans before treatment. Cine images were acquired sagittally in real time at a slice bisecting the tumor, while 4D images were acquired volumetrically. Cine MR DICOM headers were manipulated such that each respiratory frame was assigned a unique slice location. This approach permitted the treatment planning system (Eclipse, Varian Medical Systems) to recognize a complete respiratory cycle as a “volume”, where the gross tumor was contoured temporally. Software was developed to calculate the union of all frame contours in the structure set, resulting in the corresponding plane of the ITV projecting through the middle of the tumor, defined as the Internal Target Area (ITA). This was repeated for 4D-MRI, at the corresponding slice location, allowing a direct comparison of ITAs obtained from each modality. Results: Four patients have been analyzed. ITAs contoured from 4D-MRI correlate with contours from Cine MRI. The mean error of 4D values relative to Cine values is 7.67 +/− 2.55 %. No single ITA contoured from 4D-MRI demonstrated more than 10.5 % error compared to its Cine MRI counterpart. Conclusion: Motion management is a significant aspect of treatment planning within dynamic environments such as the liver, where diaphragmatic and cardiac activity influence plan accuracy. This small pilot study suggests that 4D-MRI based ITA measurements agree with Cine MRI based measurements, an important step towards clinical implementation. NIH 1R21

CT and MRI findings in patients with hyperglycemic encephalopathy : three cases report

International Nuclear Information System (INIS)

Chung, Sun Hee; Choi, Hye Young

2000-01-01

We describe the distinctive brain CT and MRI findings seen in the putamen of three patients with hyperglycemia. The chief complaint of these patients was either chorea (n=3D1) or mental change (n=3D2). They showed hyperglycemia, but physical examination and laboratory data revealed no other abnormalities. In all patients, non-enhanced CT scanning revealed high-attenuated lesions in the unilateral putamen. In two of the three patients, brain MRI performed two days after the onset of symptoms showed an abnormally high signal on T1-weighted images and a low signal on T2-weighted images. One patient had a history of diabetes mellitus, and another had acute myocardiac infarction. The third had no specific history. After the correction of hyperglycemia, the patient's symptoms subsided and diabetes mellitus was diagnosed. (author)

CT and MRI findings in patients with hyperglycemic encephalopathy : three cases report

Energy Technology Data Exchange (ETDEWEB)

Chung, Sun Hee; Choi, Hye Young [College of Medicine, Ewha Womans Unviersity, Seoul (Korea, Republic of)

2000-03-01

We describe the distinctive brain CT and MRI findings seen in the putamen of three patients with hyperglycemia. The chief complaint of these patients was either chorea (n=3D1) or mental change (n=3D2). They showed hyperglycemia, but physical examination and laboratory data revealed no other abnormalities. In all patients, non-enhanced CT scanning revealed high-attenuated lesions in the unilateral putamen. In two of the three patients, brain MRI performed two days after the onset of symptoms showed an abnormally high signal on T1-weighted images and a low signal on T2-weighted images. One patient had a history of diabetes mellitus, and another had acute myocardiac infarction. The third had no specific history. After the correction of hyperglycemia, the patient's symptoms subsided and diabetes mellitus was diagnosed. (author)

MRI of the cervical spine with 3D gradient echo sequence at 3 T: initial experience

International Nuclear Information System (INIS)

Xiao, L.; Siu, C.W.J.; Yeung, K.; Leung, A.; Yuen, M.K.; Wong, Y.C.

2015-01-01

Aim: The aim of this study was to compare three-dimensional (3D) high resolution T2*-weighted gradient echo (3D FFE) magnetic resonance (MR) sequence with conventional 2D T2-weighted turbo spin echo (TSE) MR sequence for imaging of the cervical spine, especially to assess the detectability of the internal anatomy of the cervical spinal cord, i.e. to distinguish the grey and white matter. Methods: Fifteen volunteers were examined at 3.0T MR unit. Signal-to-noise (SNR), contrast-to-noise (CNR) and image homogeneity were evaluated. In the visual analysis, the visibility of anatomical structures of the cervical spine and artifacts were assessed. The nonparametric method of paired sample t-test was adopted to evaluate the differences between the sequences. Results: The 3D FFE sequence provided better results for CNR, cerebrospinal fluid (CSF) versus white matter, grey matter, disk and bone. Moreover, it yielded good results for the CNR grey matter versus white matter. The butterfly-shaped “H” is clearly displayed in the 3D FFE sequence. The statistical analysis revealed the statistically significant difference between the 2D TSE and 3D FFE sequences for the contrast of CSF versus spinal cord (both grey matter and white matter). Conclusion: The 3D FFE sequence in MR imaging of the cervical spinal cord is superior in delineation of spinal cord anatomical structures compared to 2D TSE sequence. -- Highlights: •We investigate the potential of 3D FFE sequence to distinguish the grey-white of the cervical spinal cord at 3T MRI system. •We optimized The 3D FFE sequence was optimized to increase the grey-white contrast. •Utilizing medium TE for T2W and the shortest TR for reduction of susceptibility related artifacts and motion artefacts. •This technique may increase the confidence in the diagnosis of disease with the improved delineation of cord anatomy

Validity and reliability of 3D US for the detection of erosions in patients with rheumatoid arthritis using MRI as the gold standard

DEFF Research Database (Denmark)

Ellegaard, K; Bliddal, H; Møller Døhn, U

2014-01-01

PURPOSE: To test the reliability and validity of a 3D US erosion score in RA using MRI as the gold standard. MATERIALS AND METHODS: RA patients were examined with 3D US and 3 T MRI over the 2nd and 3rd metacarpophalangeal joints. 3D blocks were evaluated by two investigators. The erosions were...... estimated according to a semi-quantitative score (SQS) (0 - 3) and a quantitative score (QS) (mm²). MRI was evaluated according to the RAMRIS score. For the estimation of reliability, intra-class correlation coefficients (ICC) were used. Validity was tested using Spearman's rho (rs). The sensitivity...... and specificity were also calculated. RESULTS: 28 patients with RA were included. The ICC for the inter-observer reliability in the QS was 0.41 and 0.13 for the metacarpal bone and phalangeal bone, respectively, and 0.86 and 0.16, respectively, in the SQS.  The ICC for the intra-observer reliability in the QS...

Evaluation of anterior pituitary gland volume in childhood using three-dimensional MRI

International Nuclear Information System (INIS)

Marziali, Simone; Gaudiello, Fabrizio; Ferone, Ernesto; Colangelo, Vittorio; Floris, Roberto; Simonetti, Giovanni; Bozzao, Alessandro; Scire, Giuseppe; Simonetti, Alessandra; Boscherini, Brunetto

2004-01-01

Background: Three-dimensional MRI (3D-MRI) is a reliable tool for the evaluation of anatomical volumes. Volumetric measurement of the normal anterior pituitary gland in childhood has been performed in the past by 2D-MRI calculations, but has inherent inaccuracies. Objective: To obtain accurate normal anterior pituitary gland volume in childhood using 3D-MRI coronal sections. Materials and methods: The anterior pituitary gland was measured using coronal T1-weighted 3D-gradient-echo sequences (section thickness 0.75 mm). The study group was composed of 95 prepubertal children (age range 2 months-10 years) with clinically normal pituitary function and no pituitary or brain abnormalities. Results: A measurement error of 0.2-0.4% was assessed by using a phantom study. Volumetric evaluation of the anterior pituitary gland showed progressive growth of the gland from a mean 131±24 mm 3 at 2-12 months, to 249±25 mm 3 at 1-4 years and 271±29 mm 3 at 5-10 years. Conclusions: These data may be useful for paediatricians in the evaluation of patients with neuroendocrine diseases, in particular growth hormone deficiency. (orig.)

An open source, 3D printed preclinical MRI phantom for repeated measures of contrast agents and reference standards.

Science.gov (United States)

Cox, B L; Ludwig, K D; Adamson, E B; Eliceiri, K W; Fain, S B

2018-03-01

In medical imaging, clinicians, researchers and technicians have begun to use 3D printing to create specialized phantoms to replace commercial ones due to their customizable and iterative nature. Presented here is the design of a 3D printed open source, reusable magnetic resonance imaging (MRI) phantom, capable of flood-filling, with removable samples for measurements of contrast agent solutions and reference standards, and for use in evaluating acquisition techniques and image reconstruction performance. The phantom was designed using SolidWorks, a computer-aided design software package. The phantom consists of custom and off-the-shelf parts and incorporates an air hole and Luer Lock system to aid in flood filling, a marker for orientation of samples in the filled mode and bolt and tube holes for assembly. The cost of construction for all materials is under $90. All design files are open-source and available for download. To demonstrate utility, B 0 field mapping was performed using a series of gadolinium concentrations in both the unfilled and flood-filled mode. An excellent linear agreement (R 2 >0.998) was observed between measured relaxation rates (R 1 /R 2 ) and gadolinium concentration. The phantom provides a reliable setup to test data acquisition and reconstruction methods and verify physical alignment in alternative nuclei MRI techniques (e.g. carbon-13 and fluorine-19 MRI). A cost-effective, open-source MRI phantom design for repeated quantitative measurement of contrast agents and reference standards in preclinical research is presented. Specifically, the work is an example of how the emerging technology of 3D printing improves flexibility and access for custom phantom design.

Plaque characterization in ex vivo MRI evaluated by dense 3D correspondence with histology

DEFF Research Database (Denmark)

van Engelen, Arna; de Bruijne, Marleen; Klein, Stefan

2011-01-01

registration of histology data with ex vivo MRI data, using non-rigid registration, both for training and evaluation. This is more objective than previously presented methods, as it eliminates selection bias that is introduced when 2D MRI slices are manually matched to histological slices before evaluation....... Histological slices of human atherosclerotic plaques were manually segmented into necrotic core, fibrous tissue and calcification. Classification of these three components was voxelwise evaluated. As features the intensity, gradient magnitude and Laplacian in four MRI sequences after different degrees...

Distribution pattern of MRI abnormalities within the knee and wrist of juvenile idiopathic arthritis patients: signature of disease activity

NARCIS (Netherlands)

Nusman, Charlotte M.; Hemke, Robert; Schonenberg, Dieneke; Dolman, Koert M.; van Rossum, Marion A. J.; van den Berg, J. Merlijn; Kuijpers, Taco W.; Maas, Mario

2014-01-01

The aim of this study in clinically active juvenile idiopathic arthritis (JIA) was to assess the frequency and distribution pattern of synovitis as hallmark of disease and additional soft-tissue and bony abnormalities on MRI in the knee and wrist as two target joints. MRI datasets of 153 clinically

Relevance of 3D Cholangiography and Transient Elastography to Assess Cystic Fibrosis-Associated Liver Disease?

Directory of Open Access Journals (Sweden)

C. Lemaitre

2016-01-01

Full Text Available Background. Cystic fibrosis-associated liver disease (CFLD is a major cause of death. The objective of our retrospective study was to describe the relevance of magnetic resonance imaging (MRI and liver stiffness measurement (LSM for CFLD evaluation. Methods. All cystic fibrosis adult patients evaluated by MRI and LSM were included. MR signs of portal hypertension (PHT, dysmorphia, or cholangitis were collected and LSM expressed in kPa and Metavir. Results. Of 25 patients, 52% had abnormal MRI. Median LSM was 5.7 kPa (3.4–9.9. Three patients had F2 score and one had F3 score. In patients with PHT, LSM was 7.85 kPa (3.7–9.9 compared to 5 (3.4–7.5 in others, p=0.02. In patients with abnormal liver function tests, 50% had increased LSM (≥F2, whereas 94% with normal tests had normal LSM (p=0.04. Seven patients had abnormal MRI despite normal ultrasonography. Conclusions. MRI and LSM provide useful information on CFLD and may help to screen patients with PHT.

Unexplained mental retardation: is brain MRI useful?

Energy Technology Data Exchange (ETDEWEB)

Decobert, Fabrice; Merzoug, Valerie; Kalifa, Gabriel; Adamsbaum, Catherine [Saint Vincent de Paul Hospital, Department of Radiology, 75674 Paris Cedex 14 (France); Grabar, Sophie [Cochin Hospital, Department of Biostatistics and Medical Information, Paris (France); Ponsot, Gerard [Saint Vincent de Paul Hospital, Department of Neuropaediatrics, Paris (France); Des Portes, Vincent [Saint Vincent de Paul Hospital, Department of Neuropaediatrics, Paris (France); Debrousse Hospital, Department of Neuropaediatrics, Lyon (France)

2005-06-01

Mental retardation (MR), defined as an IQ below 70, is a frequent cause of consultation in paediatrics. To evaluate the yield of brain MRI in the diagnostic work-up of unexplained MR in children. Patients and methods: The MRI features and clinical data of 100 patients (age 1-18 years) affected with non-progressive MR of unknown origin were compared to an age-matched control group (n=100). Two radiologists conducted an independent review of the MRI scans. Univariate and multivariate analyses showed a higher incidence of brain anomalies in the MR group than in the control group (53 vs 17, OR=5.7 [2.9-11.1]), for signal abnormalities within the periventricular white matter (OR=20.3 [2.6-155.3]), lateral ventricular dilatation (OR=15.6 [2.0-124]), mild corpus callosum abnormalities (shortness, atrophy) (OR=6.8 [1.8-25.6]) and subtle cerebellar abnormalities, including fissure enlargement (OR=5.2 [1.1-26.2]). The diagnostic value of MRI abnormalities was considered good in 5% of patients (Alexander disease n=1, diffuse cortical malformation n=1, leukomalacia n=1, vermian agenesis n=1, commissural agenesis n=1), and weak in 48% of patients, in whom non-specific abnormalities did not lead to a diagnosis. Some clinical features resulted in a significantly higher percentage of abnormal MRI scans: abnormal neurological examination (82% vs 47%, P=0.008), abnormal skull circumference (66% vs 49%, P=0.04). Motor delay was associated with cerebellar abnormalities (P=0.01). (orig.)

Unexplained mental retardation: is brain MRI useful?

International Nuclear Information System (INIS)

Decobert, Fabrice; Merzoug, Valerie; Kalifa, Gabriel; Adamsbaum, Catherine; Grabar, Sophie; Ponsot, Gerard; Des Portes, Vincent

2005-01-01

Mental retardation (MR), defined as an IQ below 70, is a frequent cause of consultation in paediatrics. To evaluate the yield of brain MRI in the diagnostic work-up of unexplained MR in children. Patients and methods: The MRI features and clinical data of 100 patients (age 1-18 years) affected with non-progressive MR of unknown origin were compared to an age-matched control group (n=100). Two radiologists conducted an independent review of the MRI scans. Univariate and multivariate analyses showed a higher incidence of brain anomalies in the MR group than in the control group (53 vs 17, OR=5.7 [2.9-11.1]), for signal abnormalities within the periventricular white matter (OR=20.3 [2.6-155.3]), lateral ventricular dilatation (OR=15.6 [2.0-124]), mild corpus callosum abnormalities (shortness, atrophy) (OR=6.8 [1.8-25.6]) and subtle cerebellar abnormalities, including fissure enlargement (OR=5.2 [1.1-26.2]). The diagnostic value of MRI abnormalities was considered good in 5% of patients (Alexander disease n=1, diffuse cortical malformation n=1, leukomalacia n=1, vermian agenesis n=1, commissural agenesis n=1), and weak in 48% of patients, in whom non-specific abnormalities did not lead to a diagnosis. Some clinical features resulted in a significantly higher percentage of abnormal MRI scans: abnormal neurological examination (82% vs 47%, P=0.008), abnormal skull circumference (66% vs 49%, P=0.04). Motor delay was associated with cerebellar abnormalities (P=0.01). (orig.)

MRI of the anterior talofibular ligament, talar cartilage and os subfibulare: Comparison of isotropic resolution 3D and conventional 2D T2-weighted fast spin-echo sequences at 3.0 T

Energy Technology Data Exchange (ETDEWEB)

Yi, Jisook; Cha, Jang Gyu [Soonchunhyang University Bucheon Hospital, Department of Radiology, Wonmi-gu, Bucheon-si (Korea, Republic of); Lee, Young Koo [Soonchunhyang University Bucheon Hospital, Department of Orthopedics, Wonmi-gu, Bucheon-si (Korea, Republic of); Lee, Bo Ra [Soonchunhyang University Bucheon Hospital, Department of Biomedical Statistics, Wonmi-gu, Bucheon-si (Korea, Republic of); Jeon, Chan Hong [Soonchunhyang University Bucheon Hospital, Division of Rheumatology, Department of Internal Medicine, Wonmi-gu, Bucheon-si (Korea, Republic of)

2016-07-15

To determine the accuracy of a three-dimensional (3D) T2-weighted fast spin-echo (FSE) magnetic resonance (MR) sequence compared with two-dimensional (2D) sequence for diagnosing anterior talofibular ligament (ATFL) tears, chondral lesion of the talus (CLT) and os subfibulare/avulsion fracture of the distal fibula (OSF). Thirty-five patients were included, who had undergone ankle MRI with 3D T2-weighted FSE and 2D T2-weighted FSE sequences, as well as subsequent ankle arthroscopy, between November 2013 and July 2014. Each MR imaging sequence was independently scored by two readers retrospectively for the presence of ATFL tears, CLT and OSF. The area under the receiver operating curve (AUC) was compared to determine the discriminatory power of the two image sequences. Interobserver agreement was expressed as unweighted kappa value. Arthroscopic findings confirmed 21 complete tears of the ATFL, 14 partial tears of the ATFL, 17 CLTs and 7 OSFs. There were no significant differences in the diagnoses of ATFL tears (p = 0.074-0.501), CLT (p = 0.090-0.450) and OSF (p = 0.317) obtained from the 2D and 3D sequences by either reader. The interobserver agreement rates between two readers using the 3D T2-weighted FSE sequence versus those obtained with the 2D sequence were substantial (κ = 0.659) versus moderate (κ = 0.553) for ATFL tears, moderate (κ = 0.499) versus substantial (κ = 0.676) for CLT and substantial (κ = 0.621) versus substantial (κ = 0.689) for OSF. Three-dimensional isotropic T2-weighted FSE MRI of the ankle resulted in no statistically significant difference in diagnostic performance compared to two-dimensional T2-weighted FSE MRI in the evaluation of ATFL tears, CLTs and OSFs. (orig.)

MRI of the anterior talofibular ligament, talar cartilage and os subfibulare: Comparison of isotropic resolution 3D and conventional 2D T2-weighted fast spin-echo sequences at 3.0 T

International Nuclear Information System (INIS)

Yi, Jisook; Cha, Jang Gyu; Lee, Young Koo; Lee, Bo Ra; Jeon, Chan Hong

2016-01-01

To determine the accuracy of a three-dimensional (3D) T2-weighted fast spin-echo (FSE) magnetic resonance (MR) sequence compared with two-dimensional (2D) sequence for diagnosing anterior talofibular ligament (ATFL) tears, chondral lesion of the talus (CLT) and os subfibulare/avulsion fracture of the distal fibula (OSF). Thirty-five patients were included, who had undergone ankle MRI with 3D T2-weighted FSE and 2D T2-weighted FSE sequences, as well as subsequent ankle arthroscopy, between November 2013 and July 2014. Each MR imaging sequence was independently scored by two readers retrospectively for the presence of ATFL tears, CLT and OSF. The area under the receiver operating curve (AUC) was compared to determine the discriminatory power of the two image sequences. Interobserver agreement was expressed as unweighted kappa value. Arthroscopic findings confirmed 21 complete tears of the ATFL, 14 partial tears of the ATFL, 17 CLTs and 7 OSFs. There were no significant differences in the diagnoses of ATFL tears (p = 0.074-0.501), CLT (p = 0.090-0.450) and OSF (p = 0.317) obtained from the 2D and 3D sequences by either reader. The interobserver agreement rates between two readers using the 3D T2-weighted FSE sequence versus those obtained with the 2D sequence were substantial (κ = 0.659) versus moderate (κ = 0.553) for ATFL tears, moderate (κ = 0.499) versus substantial (κ = 0.676) for CLT and substantial (κ = 0.621) versus substantial (κ = 0.689) for OSF. Three-dimensional isotropic T2-weighted FSE MRI of the ankle resulted in no statistically significant difference in diagnostic performance compared to two-dimensional T2-weighted FSE MRI in the evaluation of ATFL tears, CLTs and OSFs. (orig.)

Reduced GABA{sub A} receptor density contralateral to a potentially epileptogenic MRI abnormality in a patient with complex partial seizures

Energy Technology Data Exchange (ETDEWEB)

Kuwert, T. [Dept. of Nuclear Medicine, Muenster Univ. (Germany); Stodieck, S.R.G. [Dept. of Neurology, Muenster Univ. (Germany); Puskas, C. [Dept. of Nuclear Medicine, Muenster Univ. (Germany); Diehl, B. [Dept. of Neurology, Muenster Univ. (Germany); Puskas, Z. [Inst. of Clinical Radiology, Muenster Univ. (Germany); Schuierer, G. [Inst. of Clinical Radiology, Muenster Univ. (Germany); Vollet, B. [Dept. of Nuclear Medicine, Muenster Univ. (Germany); Schober, O. [Dept. of Nuclear Medicine, Muenster Univ. (Germany)

1996-01-01

Imaging cerebral GABA{sub A} receptor density (GRD) with single-photon emission tomography (SPET) and iodine-123 iomazenil is highly accurate in lateralizing epileptogenic foci in patients with complex partial seizures of temporal origin. Limited knowledge exists on how iomazenil SPET compares with magnetic resonance imaging (MRI) in this regard. We present a patient with complex partial seizures in whom MRI had identified an arachnoid cyst anterior to the tip of the left temporal lobe. Contralaterally to this structural abnormality, interictal electroencephalography (EEG) performed after sleep deprivation disclosed an intermittent frontotemporal dysrhythmic focus with slow and sharp waves. On iomazenil SPET images GRD was significantly reduced in the right temporal lobe and thus contralaterally to the MRI abnormality, but ipsilaterally to the pathological EEG findings. These data suggest that iomazenil SPET may significantly contribute to the presurgical evaluation of epileptic patients even when MRI identifies potentialy epileptogenic structural lesions. (orig.)

3D conformal MRI-controlled transurethral ultrasound prostate therapy: validation of numerical simulations and demonstration in tissue-mimicking gel phantoms.

Science.gov (United States)

Burtnyk, Mathieu; N'Djin, William Apoutou; Kobelevskiy, Ilya; Bronskill, Michael; Chopra, Rajiv

2010-11-21

MRI-controlled transurethral ultrasound therapy uses a linear array of transducer elements and active temperature feedback to create volumes of thermal coagulation shaped to predefined prostate geometries in 3D. The specific aims of this work were to demonstrate the accuracy and repeatability of producing large volumes of thermal coagulation (>10 cc) that conform to 3D human prostate shapes in a tissue-mimicking gel phantom, and to evaluate quantitatively the accuracy with which numerical simulations predict these 3D heating volumes under carefully controlled conditions. Eleven conformal 3D experiments were performed in a tissue-mimicking phantom within a 1.5T MR imager to obtain non-invasive temperature measurements during heating. Temperature feedback was used to control the rotation rate and ultrasound power of transurethral devices with up to five 3.5 × 5 mm active transducer elements. Heating patterns shaped to human prostate geometries were generated using devices operating at 4.7 or 8.0 MHz with surface acoustic intensities of up to 10 W cm(-2). Simulations were informed by transducer surface velocity measurements acquired with a scanning laser vibrometer enabling improved calculations of the acoustic pressure distribution in a gel phantom. Temperature dynamics were determined according to a FDTD solution to Pennes' BHTE. The 3D heating patterns produced in vitro were shaped very accurately to the prostate target volumes, within the spatial resolution of the MRI thermometry images. The volume of the treatment difference falling outside ± 1 mm of the target boundary was, on average, 0.21 cc or 1.5% of the prostate volume. The numerical simulations predicted the extent and shape of the coagulation boundary produced in gel to within (mean ± stdev [min, max]): 0.5 ± 0.4 [-1.0, 2.1] and -0.05 ± 0.4 [-1.2, 1.4] mm for the treatments at 4.7 and 8.0 MHz, respectively. The temperatures across all MRI thermometry images were predicted within -0.3 ± 1.6 °C and 0

Abnormal left superior temporal gyrus volumes in children and adolescents with bipolar disorder: a magnetic resonance imaging study.

Science.gov (United States)

Chen, Hua Hsua; Nicoletti, Mark A; Hatch, John P; Sassi, Roberto B; Axelson, David; Brambilla, Paolo; Monkul, E Serap; Keshavan, Matcheri S; Ryan, Neal D; Birmaher, Boris; Soares, Jair C

2004-06-03

Abnormalities in left superior temporal gyrus (STG) have been reported in adult bipolar patients. However, it is not known whether such abnormalities are already present early in the course of this illness. Magnetic resonance imaging (MRI) morphometric analysis of STG was performed in 16 DSM-IV children and adolescents with bipolar disorder (mean age+/-SD 15.5+/-3.4 years) and 21 healthy controls (mean age+/-SD 16.9+/-3.8 years). Subjects underwent a 3D spoiled gradient recalled acquisition MRI examination. Using analysis of covariance with age, gender and intra-cranial brain volume as covariates, we found significantly smaller left total STG volumes in bipolar patients (12.5+/-1.5 cm(3)) compared with healthy controls (13.6+/-2.5 cm(3)) (F=4.45, d.f.=1, 32, P=0.04). This difference was accounted for by significantly smaller left and right STG white matter volumes in bipolar patients. Decreased white matter connections may be the core of abnormalities in STG, which is an important region for speech, language and communication, and could possibly underlie neurocognitive deficits present in bipolar patients.

Differentiation between grade 3 and grade 4 articular cartilage defects of the knee: Fat-suppressed proton density-weighted versus fat-suppressed three-dimensional gradient-echo MRI

Energy Technology Data Exchange (ETDEWEB)

Lee, So Yeon; Jee, Won-Hee; Kim, Sun Ki (Dept. of Radiology, Seoul St Mary' s Hospital, Catholic Univ. of Korea, Seoul (Korea)), e-mail: whjee@catholic.ac.kr; Koh, In-Jun (Dept. of Joint Reconstruction Center, Seoul National Univ. Bundang Hospital, Seoul (Korea)); Kim, Jung-Man (Dept. of Orthopedic Surgery, Seoul St Mary' s Hospital, Catholic Univ. of Korea, Seoul (Korea))

2010-05-15

Background: Fat-suppressed (FS) proton density (PD)-weighted magnetic resonance imaging (MRI) and FS three-dimensional (3D) gradient-echo imaging such as spoiled gradient-recalled (SPGR) sequence have been established as accurate methods for detecting articular cartilage defects. Purpose: To retrospectively compare the diagnostic efficacy between FS PD-weighted and FS 3D gradient-echo MRI for differentiating between grade 3 and grade 4 cartilage defects of the knee with arthroscopy as the standard of reference. Material and Methods: Twenty-one patients who had grade 3 or 4 cartilage defects in medial femoral condyle at arthroscopy and knee MRI were included in this study: grade 3, >50% cartilage defects; grade 4, full thickness cartilage defects exposed to the bone. Sagittal FS PD-weighted MR images and FS 3D gradient-echo images with 1.5 T MR images were independently graded for the cartilage abnormalities of medial femoral condyle by two musculoskeletal radiologists. Statistical analysis was performed by Fisher's exact test. Inter-observer agreement in grading of cartilage was assessed using ? coefficients. Results: Arthroscopy revealed grade 3 defects in 17 patients and grade 4 defects in 4 patients in medial femoral condyles. For FS 3D gradient-echo images grade 3 defects were graded as grade 3 (n=15) and grade 4 (n=2), and all grade 4 defects (n=4) were correctly graded. However, for FS PD-weighted MR images all grade 3 defects were misinterpreted as grade 1 (n=1) and grade 4 (n=16), whereas all grade 4 defects (n=4) were correctly graded. FS 3D gradient-echo MRI could differentiate grade 3 from grade 4 defects (P=0.003), whereas FS PD-weighted imaging could not (P=1.0). Inter-observer agreement was substantial (?=0.70) for grading of cartilage using FS PD-weighted imaging, whereas it was moderate (?=0.46) using FS 3D gradient-echo imaging. Conclusion: FS 3D gradient-echo MRI is more helpful for differentiating between grade 3 and grade 4 cartilage

Clinical assessment of CT-MRI image fusion software in localization of the prostate for 3D conformal radiation therapy

International Nuclear Information System (INIS)

Kagawa, Kazufumi; Lee, W. Robert; Schultheiss, Timothy E.; Hunt, Margie A.; Shaer, Andrew H.; Hanks, Gerald E.

1996-01-01

Purpose: To assess the utility of image fusion software and compare MRI prostate localization with CT localization in patients undergoing 3D conformal radiation therapy of prostate cancer. Materials and Methods: After a phantom study was performed to ensure the accuracy of image fusion procedure, 22 prostate cancer patients had CT and MRI studies before the start of radiotherapy. Immobilization casts used during radiation treatment were also used for both imaging studies. After the clinical target volume (CTV) (prostate or prostate + seminal vesicles) was defined on CT, slices from MRI study were reconstructed to match precisely the corresponding CT slices by identifying three common bony landmarks on each study. The CTV was separately defined on the matched MRI slices. Data related to the size and location of the prostate were compared between CT and MRI. The spatial relationship between the tip of urethrogram cone on CT and prostate apex seen on MRI was also scrutinized. Results: The phantom study showed the registration discrepancies between CT and MRI smaller than 1.0 mm in any pair of comparison. The patient study showed mean image registration error of 0.9 (± 0.6) mm. The average prostate volume was 63.0 (± 25.8) cm 3 and 50.9 (± 22.9) cm 3 determined by CT and MRI respectively (Fig. 1). The difference in prostate location with the two studies most commonly differed at the base and at the apex of the prostate (Fig. 2). On transverse MRI, the prostate apex was situated 7.1 (± 4.5) mm dorsal and 15.1 (± 4.0) mm cephalad to the tip of urethrogram cone (Fig. 3). Conclusions: CT-MRI image fusion study made it possible to compare the two modalities directly. MRI localization of the prostate is more accurate than CT, and indicates the distance from cone to apex is 15 mm. In view of excellent treatment results obtained with current CT localization of the prostate, still it may not be wise to reduce target volume to that demonstrated on MRI

Disk abnormality coexists with any degree of synovial and osseous abnormality in the temporomandibular joints of children with juvenile idiopathic arthritis

International Nuclear Information System (INIS)

Kirkhus, Eva; Smith, Hans-Joergen; Arvidsson, Linda Z.; Larheim, Tore A.; Flatoe, Berit; Hetlevik, Siri O.

2016-01-01

MRI manifestation of temporomandibular joint arthritis is frequently reported in children with juvenile idiopathic arthritis. However, little attention has been paid to temporomandibular joint disk abnormalities. To assess combinations of MRI findings in the symptomatic temporomandibular joint in children with juvenile idiopathic arthritis with focus on disk abnormalities. This was a retrospective study of 46 patients with juvenile idiopathic arthritis, mean age 12 years (range: 5-17 years). Mean disease duration was 70 months (standard deviation: 61 months). MR images of 92 temporomandibular joints were scored for thickness of abnormally enhancing synovium (synovitis), joint effusion, bone marrow oedema, abnormal bone shape, bone erosion and disk abnormalities. The 92 temporomandibular joints were categorized as A: No synovitis and normal bone shape (30/92; 33%), B: Synovitis and normal bone shape (14/92: 15%), C: Synovitis and abnormal bone shape (38/92; 41%) and D: No synovitis but abnormal bone shape (10/92; 11%). Thirty-six of the 46 patients (78%) had synovitis and 33/46 (72%) had abnormal bone shape, most frequently in combination (30/46; 65%). Disk abnormalities (flat disk, fragmented disk, adherent disk and displaced disk) were found in 29/46 patients (63%). Disk abnormalities were found in all categories of juvenile idiopathic arthritis involved temporomandibular joints (B: 8/14 [57%]; C: 25/38 [66%] and D: 7/10 [70%]). Disk displacement was found in half of the joints (7/14) in category B. Synovitis was most pronounced in this category. Disk abnormalities were frequent. Disk displacement also occurred in joints with early temporomandibular joint arthritis, i.e., with normal bone shape. Other disk abnormalities were found in joints with bone abnormalities. Attention should be paid to disk abnormalities both in early and long-standing temporomandibular joint arthritis in children with juvenile idiopathic arthritis. (orig.)

Disk abnormality coexists with any degree of synovial and osseous abnormality in the temporomandibular joints of children with juvenile idiopathic arthritis

Energy Technology Data Exchange (ETDEWEB)

Kirkhus, Eva; Smith, Hans-Joergen [Oslo University Hospital, Rikshospitalet, Department of Radiology and Nuclear Medicine, Oslo (Norway); University of Oslo, Institute of Clinical Medicine, Oslo (Norway); Arvidsson, Linda Z.; Larheim, Tore A. [University of Oslo, Department of Maxillofacial Radiology, Institute of Clinical Dentistry, Oslo (Norway); Flatoe, Berit; Hetlevik, Siri O. [Oslo University Hospital, Rikshospitalet, Department of Rheumatology, Oslo (Norway); University of Oslo, Institute of Clinical Medicine, Oslo (Norway)

2016-03-15

MRI manifestation of temporomandibular joint arthritis is frequently reported in children with juvenile idiopathic arthritis. However, little attention has been paid to temporomandibular joint disk abnormalities. To assess combinations of MRI findings in the symptomatic temporomandibular joint in children with juvenile idiopathic arthritis with focus on disk abnormalities. This was a retrospective study of 46 patients with juvenile idiopathic arthritis, mean age 12 years (range: 5-17 years). Mean disease duration was 70 months (standard deviation: 61 months). MR images of 92 temporomandibular joints were scored for thickness of abnormally enhancing synovium (synovitis), joint effusion, bone marrow oedema, abnormal bone shape, bone erosion and disk abnormalities. The 92 temporomandibular joints were categorized as A: No synovitis and normal bone shape (30/92; 33%), B: Synovitis and normal bone shape (14/92: 15%), C: Synovitis and abnormal bone shape (38/92; 41%) and D: No synovitis but abnormal bone shape (10/92; 11%). Thirty-six of the 46 patients (78%) had synovitis and 33/46 (72%) had abnormal bone shape, most frequently in combination (30/46; 65%). Disk abnormalities (flat disk, fragmented disk, adherent disk and displaced disk) were found in 29/46 patients (63%). Disk abnormalities were found in all categories of juvenile idiopathic arthritis involved temporomandibular joints (B: 8/14 [57%]; C: 25/38 [66%] and D: 7/10 [70%]). Disk displacement was found in half of the joints (7/14) in category B. Synovitis was most pronounced in this category. Disk abnormalities were frequent. Disk displacement also occurred in joints with early temporomandibular joint arthritis, i.e., with normal bone shape. Other disk abnormalities were found in joints with bone abnormalities. Attention should be paid to disk abnormalities both in early and long-standing temporomandibular joint arthritis in children with juvenile idiopathic arthritis. (orig.)

4D flow mri post-processing strategies for neuropathologies

Science.gov (United States)

Schrauben, Eric Mathew

4D flow MRI allows for the measurement of a dynamic 3D velocity vector field. Blood flow velocities in large vascular territories can be qualitatively visualized with the added benefit of quantitative probing. Within cranial pathologies theorized to have vascular-based contributions or effects, 4D flow MRI provides a unique platform for comprehensive assessment of hemodynamic parameters. Targeted blood flow derived measurements, such as flow rate, pulsatility, retrograde flow, or wall shear stress may provide insight into the onset or characterization of more complex neuropathologies. Therefore, the thorough assessment of each parameter within the context of a given disease has important medical implications. Not surprisingly, the last decade has seen rapid growth in the use of 4D flow MRI. Data acquisition sequences are available to researchers on all major scanner platforms. However, the use has been limited mostly to small research trials. One major reason that has hindered the more widespread use and application in larger clinical trials is the complexity of the post-processing tasks and the lack of adequate tools for these tasks. Post-processing of 4D flow MRI must be semi-automated, fast, user-independent, robust, and reliably consistent for use in a clinical setting, within large patient studies, or across a multicenter trial. Development of proper post-processing methods coupled with systematic investigation in normal and patient populations pushes 4D flow MRI closer to clinical realization while elucidating potential underlying neuropathological origins. Within this framework, the work in this thesis assesses venous flow reproducibility and internal consistency in a healthy population. A preliminary analysis of venous flow parameters in healthy controls and multiple sclerosis patients is performed in a large study employing 4D flow MRI. These studies are performed in the context of the chronic cerebrospinal venous insufficiency hypothesis. Additionally, a

Three-dimensional MRI of the glenoid labrum

International Nuclear Information System (INIS)

Loehr, S.P.; Pope, T.L. Jr.; Martin, D.F.; Link, K.M.; Monu, J.U.V.; Hunter, M.; Reboussin, D.

1995-01-01

The objective of this study was to assess the accuracy of three-dimensional (3D) magnetic resonance imaging (MRI) reformation in the evaluation of tears of the glenoid labrum complex (GLC). Fifty-five shoulders were evaluated by MRI using standard spin-echo sequences. Gradient-refocused-echo axial projections were used to assess the GLC on the two-dimensional (2D) studies. Three-dimensional Fourier transform multiplanar gradient-recalled imaging with a resolution of 0.7 mm was also performed in all patients. Independent analyses of the anterior and posterior labra were performed in a blinded manner for both the 2D and 3D studies by three experienced musculoskeletal radiologists. Observations of the imaging studies were compared with the videoarthroscopic findings. The appearance of the GLC was rated on a scale of 0 to 4 (0-2=normal, 3, 4=abnormal or torn). The diagnostic confidence was averaged from the three reader's scores. Anterior labral tears were effectively detected with sensitivities of 89% and 96% and specificities of 96% and 100% (P<0.0001) for the 2D and 3D studies, respectively. For posterior labral tears, the sensitivity and specificity of the 2D method were 47% and 98%, respectively. The sensitivity and specificity of the 3D volume sequence were 53% and 98%, respectively. The lower sensitivity of both imaging methods for detecting posterior labral tears may be influenced by the smaller number (n=5) of arthroscopically confirmed cases in our study and reflects the difficulty of visualizing the posteroinferior borders of the GLC with present MRI techniques. (orig.)

Brain abnormalities on MRI in non-functioning pituitary adenoma patients treated with or without postoperative radiotherapy

NARCIS (Netherlands)

Sattler, Margriet G. A.; Meiners, Linda C.; Sluiter, Wim J.; van den Berg, Gerrit; Langendijk, Johannes A.; Wolffenbuttel, Bruce H. R.; van den Bergh, Alphons C. M.; van Beek, Andre P.

Background and purpose: To assess and compare brain abnormalities on Magnetic Resonance Imaging (MRI) in non-functioning pituitary macro-adenoma (NFA) patients treated with or without postoperative radiotherapy (RT). Material and methods: In 86 NFA patients, treated between 1987 and 2008 at the

Chemical exchange-sensitive spin-lock MRI of glucose analog 3-O-methyl-d-glucose in normal and ischemic brain.

Science.gov (United States)

Jin, Tao; Mehrens, Hunter; Wang, Ping; Kim, Seong-Gi

2018-05-01

Glucose transport is important for understanding brain glucose metabolism. We studied glucose transport with a presumably non-toxic and non-metabolizable glucose analog, 3-O-methyl-d-glucose, using a chemical exchange-sensitive spin-lock MRI technique at 9.4 Tesla. 3-O-methyl-d-glucose showed comparable chemical exchange properties with d-glucose and 2-deoxy-d-glucose in phantoms, and higher and lower chemical exchange-sensitive spin-lock sensitivity than Glc and 2-deoxy-d-glucose in in vivo experiments, respectively. The changes of the spin-lattice relaxation rate in the rotating frame (Δ R 1 ρ) in normal rat brain peaked at ∼15 min after the intravenous injection of 1 g/kg 3-O-methyl-d-glucose and almost maintained a plateau for >1 h. Doses up to 4 g/kg 3-O-methyl-d-glucose were linearly correlated with Δ R 1 ρ. In rats with focal ischemic stroke, chemical exchange-sensitive spin-lock with 3-O-methyl-d-glucose injection at 1 h after stroke onset showed reduced Δ R 1 ρ in the ischemic core but higher Δ R 1 ρ in the peri-core region compared to normal tissue, which progressed into the ischemic core at 3 h after stroke onset. This suggests that the hyper-chemical exchange-sensitive spin-lock region observed at 1 h is the ischemic penumbra at-risk of infarct. In summary, 3-O-methyl-d-glucose-chemical exchange-sensitive spin-lock can be a sensitive MRI technique to probe the glucose transport in normal and ischemic brains.

MRI abnormalities of foot and ankle in asymptomatic, physically active individuals

International Nuclear Information System (INIS)

Lohman, M.; Kivisaari, A.; Kivisaari, L.; Kallio, P.

2001-01-01

Objective. To assess MRI changes in the ankle and foot after physical exercise.Design and patients. Nineteen non-professional marathon runners and 19 age- and sex-matched controls volunteered for the study. All had ankle and foot MR images (1.5 T) taken in three perpendicular planes (STIR, T2F and T1FS sequences) within 3 h of running a full-length marathon (42.125 km). Three radiologists independently analysed the groups on a masked basis using a predefined form.Results. Severe bone marrow oedema was seen in one and slight bone marrow oedema in three marathon runners. Slight bone marrow oedema was found in three control subjects. Signal alteration within the soleus muscle, consistent with a grade 1 strain, was found in one marathon runner. Small punctate hyperintensities within the Achilles tendon were seen in 26% of the marathon runners and in 63% of controls (P=0.016). An increased amount of fluid in the retrocalcaneal bursa was found in one control and in none of the marathon runners. Small amounts of fluid in the retrocalcaneal bursa were seen in 68% of marathon runners and in 53% of controls. Grade 1 or 2 peritendinous joint fluid was found around 22% of tendons, among both marathon runners and controls, most often involving the tendon sheath of the flexor hallucis longus muscle. An increased amount of joint fluid was noted in 34% of the joints of the marathon runners, and in 18% of the controls.Conclusion. MRI shows several abnormalities in the ankle and foot both after marathon races and in asymptomatic physically active individuals without any preceding extraordinary strain. Recreational sports may lead to a number of positive MRI findings without correlation with clinical findings. (orig.)

Striatal abnormalities in trichotillomania: A multi-site MRI analysis

Directory of Open Access Journals (Sweden)

Masanori Isobe

2018-01-01

Full Text Available Trichotillomania (hair-pulling disorder is characterized by the repetitive pulling out of one's own hair, and is classified as an Obsessive-Compulsive Related Disorder. Abnormalities of the ventral and dorsal striatum have been implicated in disease models of trichotillomania, based on translational research, but direct evidence is lacking. The aim of this study was to elucidate subcortical morphometric abnormalities, including localized curvature changes, in trichotillomania. De-identified MRI scans were pooled by contacting authors of previous peer-reviewed studies that examined brain structure in adult patients with trichotillomania, following an extensive literature search. Group differences on subcortical volumes of interest were explored (t-tests and localized differences in subcortical structure morphology were quantified using permutation testing. The pooled sample comprised N = 68 individuals with trichotillomania and N = 41 healthy controls. Groups were well-matched in terms of age, gender, and educational levels. Significant volumetric reductions were found in trichotillomania patients versus controls in right amygdala and left putamen. Localized shape deformities were found in bilateral nucleus accumbens, bilateral amygdala, right caudate and right putamen. Structural abnormalities of subcortical regions involved in affect regulation, inhibitory control, and habit generation, play a key role in the pathophysiology of trichotillomania. Trichotillomania may constitute a useful model through which to better understand other compulsive symptoms. These findings may account for why certain medications appear effective for trichotillomania, namely those modulating subcortical dopamine and glutamatergic function. Future work should study the state versus trait nature of these changes, and the impact of treatment.

MRI versus ultrasonography to assess meniscal abnormalities in acute knees.

Science.gov (United States)

Cook, James L; Cook, Cristi R; Stannard, James P; Vaughn, Gavin; Wilson, Nichole; Roller, Brandon L; Stoker, Aaron M; Jayabalan, Prakash; Hdeib, Moses; Kuroki, Keiichi

2014-08-01

While magnetic resonance imaging (MRI) is often considered the "gold standard" diagnostic imaging modality for detection of meniscal abnormalities, it is associated with misdiagnosis in as high as 47% of cases, is costly, and is not readily available to a large number of patients. Ultrasonographic examination of the knee has been reported to be an effective diagnostic tool for this purpose with the potential to overcome many of the shortcomings of MRI. The purpose of this study is to determine the clinical usefulness of ultrasonography for diagnosis of meniscal pathology in patients with acute knee pain and compare its diagnostic accuracy to MRI in a clinical setting. With Institutional Review Board approval, patients (n = 71) with acute knee pain were prospectively enrolled with informed consent. Preoperative MRI (1.5 T) was performed on each affected knee using the hospital's standard equipment and protocols and read by faculty radiologists trained in musculoskeletal MRI. Ultrasonographic assessments of each affected knee were performed by one of two faculty members trained in musculoskeletal ultrasonography using a 10 to 14 MHz linear transducer. Arthroscopic evaluation of affected knees was performed by one of three faculty orthopedic surgeons to assess and record all joint pathology, which served as the reference standard for determining presence, type, and severity of meniscal pathology. All evaluators for each diagnostic modality were blinded to all other data. Data were collected and compared by a separate investigator to determine sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), correct classification rate (CCR), likelihood ratios (LR[+] and LR[-]), and odds ratios. Preoperative ultrasonographic assessment of meniscal pathology was associated with Sn = 91.2%, Sp = 84.2%, PPV = 94.5%, NPV = 76.2%, CCR = 89.5%, LR(+) = 5.78, and LR(-) = 0.10. Preoperative MRI assessment of

Multimodal-3D imaging based on μMRI and μCT techniques bridges the gap with histology in visualization of the bone regeneration process.

Science.gov (United States)

Sinibaldi, R; Conti, A; Sinjari, B; Spadone, S; Pecci, R; Palombo, M; Komlev, V S; Ortore, M G; Tromba, G; Capuani, S; Guidotti, R; De Luca, F; Caputi, S; Traini, T; Della Penna, S

2018-03-01

Bone repair/regeneration is usually investigated through X-ray computed microtomography (μCT) supported by histology of extracted samples, to analyse biomaterial structure and new bone formation processes. Magnetic resonance imaging (μMRI) shows a richer tissue contrast than μCT, despite at lower resolution, and could be combined with μCT in the perspective of conducting non-destructive 3D investigations of bone. A pipeline designed to combine μMRI and μCT images of bone samples is here described and applied on samples of extracted human jawbone core following bone graft. We optimized the coregistration procedure between μCT and μMRI images to avoid bias due to the different resolutions and contrasts. Furthermore, we used an Adaptive Multivariate Clustering, grouping homologous voxels in the coregistered images, to visualize different tissue types within a fused 3D metastructure. The tissue grouping matched the 2D histology applied only on 1 slice, thus extending the histology labelling in 3D. Specifically, in all samples, we could separate and map 2 types of regenerated bone, calcified tissue, soft tissues, and/or fat and marrow space. Remarkably, μMRI and μCT alone were not able to separate the 2 types of regenerated bone. Finally, we computed volumes of each tissue in the 3D metastructures, which might be exploited by quantitative simulation. The 3D metastructure obtained through our pipeline represents a first step to bridge the gap between the quality of information obtained from 2D optical microscopy and the 3D mapping of the bone tissue heterogeneity and could allow researchers and clinicians to non-destructively characterize and follow-up bone regeneration. Copyright © 2017 John Wiley & Sons, Ltd.

Quantification of diaphragm mechanics in Pompe disease using dynamic 3D MRI

DEFF Research Database (Denmark)

Mogalle, Katja; Perez-Rovira, Adria; Ciet, Pierluigi

2016-01-01

BACKGROUND: Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification of respira......BACKGROUND: Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification...... methodology relies on image registration and lung surface extraction to quantify lung kinematics during breathing. This allows for the extraction of geometry and motion features of the lung that characterize the independent contribution of the diaphragm and the thoracic muscles to the respiratory cycle....... RESULTS: Results in 16 3D+t MRI scans (10 Pompe patients and 6 controls) of a slow expiratory maneuver show that kinematic analysis from dynamic 3D images reveals important additional information about diaphragm mechanics and respiratory muscle involvement when compared to conventional pulmonary function...

Heterogeneity phantoms for visualization of 3D dose distributions by MRI-based polymer gel dosimetry

International Nuclear Information System (INIS)

Watanabe, Yoichi; Mooij, Rob; Mark Perera, G.; Maryanski, Marek J.

2004-01-01

Heterogeneity corrections in dose calculations are necessary for radiation therapy treatment plans. Dosimetric measurements of the heterogeneity effects are hampered if the detectors are large and their radiological characteristics are not equivalent to water. Gel dosimetry can solve these problems. Furthermore, it provides three-dimensional (3D) dose distributions. We used a cylindrical phantom filled with BANG-3 registered polymer gel to measure 3D dose distributions in heterogeneous media. The phantom has a cavity, in which water-equivalent or bone-like solid blocks can be inserted. The irradiated phantom was scanned with an magnetic resonance imaging (MRI) scanner. Dose distributions were obtained by calibrating the polymer gel for a relationship between the absorbed dose and the spin-spin relaxation rate of the magnetic resistance (MR) signal. To study dose distributions we had to analyze MR imaging artifacts. This was done in three ways: comparison of a measured dose distribution in a simulated homogeneous phantom with a reference dose distribution, comparison of a sagittally scanned image with a sagittal image reconstructed from axially scanned data, and coregistration of MR and computed-tomography images. We found that the MRI artifacts cause a geometrical distortion of less than 2 mm and less than 10% change in the dose around solid inserts. With these limitations in mind we could make some qualitative measurements. Particularly we observed clear differences between the measured dose distributions around an air-gap and around bone-like material for a 6 MV photon beam. In conclusion, the gel dosimetry has the potential to qualitatively characterize the dose distributions near heterogeneities in 3D

Assessment of MRI Issues at 3 Tesla for a New Metallic Tissue Marker

Science.gov (United States)

Cronenweth, Charlotte M.; Shellock, Frank G.

2015-01-01

Purpose. To assess the MRI issues at 3 Tesla for a metallic tissue marker used to localize removal areas of tissue abnormalities. Materials and Methods. A newly designed, metallic tissue marker (Achieve Marker, CareFusion, Vernon Hills, IL) used to mark biopsy sites, particularly in breasts, was assessed for MRI issues which included standardized tests to determine magnetic field interactions (i.e., translational attraction and torque), MRI-related heating, and artifacts at 3 Tesla. Temperature changes were determined for the marker using a gelled-saline-filled phantom. MRI was performed at a relatively high specific absorption rate (whole body averaged SAR, 2.9-W/kg). MRI artifacts were evaluated using T1-weighted, spin echo and gradient echo pulse sequences. Results. The marker displayed minimal magnetic field interactions (2-degree deflection angle and no torque). MRI-related heating was only 0.1°C above background heating (i.e., the heating without the tissue marker present). Artifacts seen as localized signal loss were relatively small in relation to the size and shape of the marker. Conclusions. Based on the findings, the new metallic tissue marker is acceptable or “MR Conditional” (using current labeling terminology) for a patient undergoing an MRI procedure at 3 Tesla or less. PMID:26266051

[3D FSPGR (fast spoiled gradient echo) magnetic resonance imaging in the diagnosis of focal cortical dysplasia in children].

Science.gov (United States)

Alikhanov, A A; Sinitsyn, V E; Perepelova, E M; Mukhin, K Iu; Demushkina, A A; Omarova, M O; Piliia, S V

2001-01-01

Small dysplastic lesions of the cerebral cortex are often missed by conventional MRI methods. The identification of subtle structural abnormalities by traditional multiplanar rectilinear slices is often limited by the complex convolutional pattern of the brain. We used a method of FSPGR (fast spoiled gradient-echo) of three-dimensional MRI data that improves the anatomical display of the sulcal structure of the hemispheric convexities. It also reduces the asymmetric sampling of gray-white matter that may lead to false-positive results. We present 5 from 12 patients with dysplastic cortical lesions in whom conventional two-dimensional and three-dimensional MRI with multiplanar reformatting was initially considered normal. Subsequent studies using 3D FSPGR identified various types of focal cortical dysplasia in all. These results indicate that an increase in the detection of subtle focal dysplastic lesions may be accomplished when one improves the anatomical display of the brain sulcal structure by performing 3D FSPGR.

Diagnosis of glenoid labral tears using 3-tesla MRI vs. 3-tesla MRA: a systematic review and meta-analysis.

Science.gov (United States)

Ajuied, Adil; McGarvey, Ciaran P; Harb, Ziad; Smith, Christian C; Houghton, Russell P; Corbett, Steven A

2018-05-01

Various protocols exist for magnetic resonance arthrogram (MRA) of the shoulder, including 3D isotropic scanning and positioning in neutral (2D neutral MRA), or abduction-external-rotation (ABER). MRA does not improve diagnostic accuracy for labral tears when compared to magnetic resonance imaging (MRI) performed using 3-Tesla (3T) magnets. Systematic review of the Cochrane, MEDLINE, and PubMed databases according to PRISMA guidelines. Included studies compared 3T MRI or 3T MRA (index tests) to arthroscopic findings (reference test). Methodological appraisal performed using QUADAS-2. Pooled sensitivity and specificity were calculated. Ten studies including 929 patients were included. Index test bias and applicability were a concern in the majority of studies. The use of arthroscopy as the reference test raised concern of verification bias in all studies. For anterior labral lesions, 3T MRI was less sensitive (0.83 vs. 0.87 p = 0.083) than 3T 2D neutral MRA. Compared to 3T 2D neutral MRA, both 3T 3D Isotropic MRA and 3T ABER MRA significantly improved sensitivity (0.87 vs. 0.95 vs. 0.94). For SLAP lesions, 3T 2D neutral MRA was of similar sensitivity to 3T MRI (0.84 vs. 0.83, p = 0.575), but less specific (0.99 vs. 0.92 p < 0.0001). For posterior labral lesions, 3T 2D neutral MRA had greater sensitivity than 3T 3D Isotropic MRA and 3T MRI (0.90 vs. 0.83 vs. 0.83). At 3-T, MRA improved sensitivity for diagnosis of anterior and posterior labral lesions, but reduced specificity in diagnosis of SLAP tears. 3T MRA with ABER positioning further improved sensitivity in diagnosis of anterior labral tears. IV.

TU-AB-BRA-09: A Novel Method of Generating Ultrafast Volumetric Cine MRI (VC-MRI) Using Prior 4D-MRI and On-Board Phase-Skipped Encoding Acquisition for Radiotherapy Target Localization

Energy Technology Data Exchange (ETDEWEB)

Wang, C; Yin, F; Harris, W; Cai, J; Chang, Z; Ren, L [Duke University Medical Center, Durham, NC (United States)

2016-06-15

Purpose: To develop a technique generating ultrafast on-board VC-MRI using prior 4D-MRI and on-board phase-skipped encoding k-space acquisition for real-time 3D target tracking of liver and lung radiotherapy. Methods: The end-of-expiration (EOE) volume in 4D-MRI acquired during the simulation was selected as the prior volume. 3 major respiratory deformation patterns were extracted through the principal component analysis of the deformation field maps (DFMs) generated between EOE and all other phases. The on-board VC-MRI at each instant was considered as a deformation of the prior volume, and the deformation was modeled as a linear combination of the extracted 3 major deformation patterns. To solve the weighting coefficients of the 3 major patterns, a 2D slice was extracted from VC-MRI volume to match with the 2D on-board sampling data, which was generated by 8-fold phase skipped-encoding k-space acquisition (i.e., sample 1 phase-encoding line out of every 8 lines) to achieve an ultrafast 16–24 volumes/s frame rate. The method was evaluated using XCAT digital phantom to simulate lung cancer patients. The 3D volume of end-ofinhalation (EOI) phase at the treatment day was used as ground-truth onboard VC-MRI with simulated changes in 1) breathing amplitude and 2) breathing amplitude/phase change from the simulation day. A liver cancer patient case was evaluated for in-vivo feasibility demonstration. Results: The comparison between ground truth and estimated on-board VC-MRI shows good agreements. In XCAT study with changed breathing amplitude, the volume-percent-difference(VPD) between ground-truth and estimated tumor volumes at EOI was 6.28% and the Center-of-Mass-Shift(COMS) was 0.82mm; with changed breathing amplitude and phase, the VPD was 8.50% and the COMS was 0.54mm. The study of liver patient case also demonstrated a promising in vivo feasibility of the proposed method Conclusion: Preliminary results suggest the feasibility to estimate ultrafast VC-MRI for on

TU-AB-BRA-09: A Novel Method of Generating Ultrafast Volumetric Cine MRI (VC-MRI) Using Prior 4D-MRI and On-Board Phase-Skipped Encoding Acquisition for Radiotherapy Target Localization

International Nuclear Information System (INIS)

Wang, C; Yin, F; Harris, W; Cai, J; Chang, Z; Ren, L

2016-01-01

Purpose: To develop a technique generating ultrafast on-board VC-MRI using prior 4D-MRI and on-board phase-skipped encoding k-space acquisition for real-time 3D target tracking of liver and lung radiotherapy. Methods: The end-of-expiration (EOE) volume in 4D-MRI acquired during the simulation was selected as the prior volume. 3 major respiratory deformation patterns were extracted through the principal component analysis of the deformation field maps (DFMs) generated between EOE and all other phases. The on-board VC-MRI at each instant was considered as a deformation of the prior volume, and the deformation was modeled as a linear combination of the extracted 3 major deformation patterns. To solve the weighting coefficients of the 3 major patterns, a 2D slice was extracted from VC-MRI volume to match with the 2D on-board sampling data, which was generated by 8-fold phase skipped-encoding k-space acquisition (i.e., sample 1 phase-encoding line out of every 8 lines) to achieve an ultrafast 16–24 volumes/s frame rate. The method was evaluated using XCAT digital phantom to simulate lung cancer patients. The 3D volume of end-ofinhalation (EOI) phase at the treatment day was used as ground-truth onboard VC-MRI with simulated changes in 1) breathing amplitude and 2) breathing amplitude/phase change from the simulation day. A liver cancer patient case was evaluated for in-vivo feasibility demonstration. Results: The comparison between ground truth and estimated on-board VC-MRI shows good agreements. In XCAT study with changed breathing amplitude, the volume-percent-difference(VPD) between ground-truth and estimated tumor volumes at EOI was 6.28% and the Center-of-Mass-Shift(COMS) was 0.82mm; with changed breathing amplitude and phase, the VPD was 8.50% and the COMS was 0.54mm. The study of liver patient case also demonstrated a promising in vivo feasibility of the proposed method Conclusion: Preliminary results suggest the feasibility to estimate ultrafast VC-MRI for on

MRI findings of the brainstem of the neuro-Behcet syndrome

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Fujiki, Naoto; Tashiro, Kunio; Yamada, Takayoshi; Ito, Kazunori; Honma, Sanae; Doi, Shizuki; Moriwaka, Fumio

1987-10-01

We reported three cases of neuro-Behcet's syndrome which showed brainstem lesions on MRI compatible with the clinical symptoms. In Case 1, MRI showed a large, abnormal signal-intensity area in the pons and small, abnormal signal-intensity areas at the right cerebral peduncle, the bilateral basal ganglia, and the left thalamus. These lesions disappeared on MRI, in accordance with the remission of clinical symptoms. On the other hand, CT showed no positive findings. In Case 2, an abnormal signal-intensity area was disclosed at the left cerebral peduncle on MRI. This lesion was also identified on the CT scan. In Case 3, an abnormal signal-intensity area was present in the pons on MRI. In this case, CT showed no positive findings. In Cases 2 and 3, these lesions seemed to represent inflammatory or necrotic areas attributable to vasculitis;however, the extensive brainstem lesion seen on the MRI of Case 1 was a quite unique finding, for which no exact pathophysiological explanation is possible at the present time.

Electroencephalography and Brain MRI Patterns in Encephalopathy.

Science.gov (United States)

Wabulya, Angela; Lesser, Ronald P; Llinas, Rafael; Kaplan, Peter W

2016-04-01

Using electroencephalography (EEG) and histology in patients with diffuse encephalopathy, Gloor et al reported that paroxysmal synchronous discharges (PSDs) on EEG required combined cortical gray (CG) and "subcortical" gray (SCG) matter pathology, while polymorphic delta activity (PDA) occurred in patients with white matter pathology. In patients with encephalopathy, we compared EEG findings and magnetic resonance imaging (MRI) to determine if MRI reflected similar pathological EEG correlations. Retrospective case control study of 52 cases with EEG evidence of encephalopathy and 50 controls without evidence of encephalopathy. Review of clinical, EEG and MRI data acquired within 4 days of each other. The most common EEG finding in encephalopathy was background slowing, in 96.1%. We found PSDs in 0% of cases with the combination of CG and SCG abnormalities. Although 13.5% (n=7) had PSDs on EEG; 3 of these had CG and 4 had SCG abnormalities. A total of 73.1% (38/52) had white matter abnormalities-of these 28.9% (11/38) had PDA. PSDs were found with either CG or "SCG" MRI abnormalities and did not require a combination of the two. In agreement with Gloor et al, PDA occurred with white matter MRI abnormalities in the absence of gray matter abnormalities. © EEG and Clinical Neuroscience Society (ECNS) 2015.

The cerebellar development in chinese children-a study by voxel-based volume measurement of reconstructed 3D MRI scan.

Science.gov (United States)

Wu, Kuan-Hsun; Chen, Chia-Yuan; Shen, Ein-Yiao

2011-01-01

Cerebellar disorder was frequently reported to have relation with structural brain volume alteration and/or morphology change. In dealing with such clinical situations, we need a convenient and noninvasive imaging tool to provide clinicians with a means of tracing developmental changes in the cerebellum. Herein, we present a new daily practice method for cerebellum imaging that uses a work station and a software program to process reconstructed 3D neuroimages after MRI scanning. In a 3-y period, 3D neuroimages reconstructed from MRI scans of 50 children aged 0.2-12.7 y were taken. The resulting images were then statistically analyzed against a growth curve. We observed a remarkable increase in the size of the cerebellum in the first 2 y of life. Furthermore, the unmyelinated cerebellum grew mainly between birth and 2 y of age in the postnatal stage. In contrast, the postnatal development of the brain mainly depended on the growth of myelinated cerebellum from birth through adolescence. This study presents basic data from a study of ethnic Chinese children's cerebellums using reconstructed 3D brain images. Based on the technique we introduce here, clinicians can evaluate the growth of the brain.

CSF abnormalities can be predicted by VEP and MRI pathology in the examination of optic neuritis

DEFF Research Database (Denmark)

Vinter, Matilda Degn; Nielsen, Signe Modvig; Larsson, Henrik B W

2012-01-01

be valuable in the evaluation of patients with ON. We analyzed CSF findings in patients referred with ON in the context of MRI and visual evoked potential (VEP) pathology. We assessed the possible contributory role of a lumbar puncture and weigh this against disadvantages of the procedure. Between February...... causes of their symptoms and patients with >3 months between onset and tests were excluded. All files were reviewed retrospectively. CSF leukocytes and the IgG index were elevated in 33 and 41 %, respectively, and OCBs were detected in 61 % of patients. CSF abnormalities correlated strongly with VEP...

MRI of degenerative bone marrow lesions in experimental osteoarthritis of canine knee joints

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Nolte-Ernsting, C.C.A. [Department of Diagnostic Radiology, University of Technology, Aachen, Pauwelsstrasse 30, D-52057 Aachen (Germany); Adam, G. [Department of Diagnostic Radiology, University of Technology, Aachen, Pauwelsstrasse 30, D-52057 Aachen (Germany); Buehne, M. [Department of Diagnostic Radiology, University of Technology, Aachen, Pauwelsstrasse 30, D-52057 Aachen (Germany); Prescher, A. [Department of Anatomy, University of Technology, Aachen (Germany); Guenther, R.W. [Department of Diagnostic Radiology, University of Technology, Aachen, Pauwelsstrasse 30, D-52057 Aachen (Germany)

1996-07-01

Objective. The objective of this study was to determine the value of MRI in the detection of degenerative bone marrow abnormalities in an animal osteoarthritis model. Design. In 10 dogs with experimentally induced unilateral osteoarthritis of the knee, MRI was performed using two-dimensional spin-echo (2D-SE) and three-dimensional gradient-echo (3D-GE) imaging. Contrast enhanced T1-weighted 2D-SE sequences were also obtained after injection of gadolinium-DTPA. The results were compared with the gross and histopathologic findings and with radiography. Results. Histopathologic specimens revealed 21 osteosclerotic lesions and 5 intraosseous cysts. On 2D-SE images, 24 of 26 lesions were detected, while 21 of 26 lesions were identified on 2D-GE sequences. Radiography, including conventional tomography, demonstrated 9 of 26 lesions. Regardless of the sequence weighting, all osteosclerotic lesions appeared hypointense on MRI. Signal loss in bone sclerosis resulted primarily from the reduction of intact fat marrow, the increased bone density being of secondary importance. Quantitative signal analysis allowed approximate estimation of the grade of sclerosis. On postcontrast images, sclerotic bone remained hypointense, although significant but non-specific enhancement relative to the normal fat marrow was observed. The extent of contrast enhancement did not correlate with the grade of osteosclerosis. All five cysts were readily diagnosed by MRI. Cysts displayed either central or marginal contrast enhancement within their cavities. Conclusions. MRI provides a sensitive method for the diagnosis of osteoarthritic bone abnormalities, allowing their differentiation from most non-degenerative subarticular lesions. (orig.). With 1 tab.

Comparison of the utility of whole-body MRI with and without contrast-enhanced Quick 3D and double RF fat suppression techniques, conventional whole-body MRI, PET/CT and conventional examination for assessment of recurrence in NSCLC patients

International Nuclear Information System (INIS)

Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Takenaka, Daisuke; Seki, Shinichiro; Tsubakimoto, Maho; Sugimura, Kazuro

2013-01-01

Purpose: The purpose of this study was to compare diagnostic capabilities for assessment of recurrence in non-small cell lung cancer (NSCLC) patients by contrast-enhanced whole-body MRI (CE-WB-MRI) with and without CE-Quick 3D and double RF fat suppression technique (DFS), FDG-PET/CT and conventional radiological examinations. Materials and methods: A total of 134 pathologically proven and completely resected NSCLC patients (78 males, 56 females; mean age: 72 years) underwent FDG-PET/CT, CE-WB-MRI with and without Quick 3D and DFS at 3 T as well as conventional radiological examinations. The probability of recurrence was assessed with a 5-point scoring system on a per-patient basis, and final diagnosis was made by consensus between two readers. The capability for overall recurrence assessment by all the methods was compared by means of ROC analysis and their sensitivity, specificity and accuracy by means of McNemar's test. Results: Although areas under the curve did not show any significant differences, specificity (100%) and accuracy (95.5%) of CE-WB-MRI with CE-Quick 3D and DFS were significantly higher than those of FDG-PET/CT (specificity: 93.6%, p = 0.02; accuracy: 89.6%, p = 0.01) and conventional radiological examinations (specificity: 92.7%, p = 0.01; accuracy: 91.0%, p = 0.03). In addition, specificity of CE-WB-MRI without CE-Quick 3D and DFS (100%) was significantly higher than that of FDG-PET/CT (p = 0.02) and conventional radiological examinations (p = 0.01). Conclusion: Specificity and accuracy of CE-WB-MRI with CE-Quick 3D and DFS for assessment of recurrence in NSCLC patients are at least as high as, or higher than those of others

Comparison of the utility of whole-body MRI with and without contrast-enhanced Quick 3D and double RF fat suppression techniques, conventional whole-body MRI, PET/CT and conventional examination for assessment of recurrence in NSCLC patients

Energy Technology Data Exchange (ETDEWEB)

Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Nishio, Mizuho [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Koyama, Hisanobu [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Yoshikawa, Takeshi; Matsumoto, Sumiaki [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Takenaka, Daisuke [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Department of Radiology, Hyogo Cancer Center, Akashi (Japan); Seki, Shinichiro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Tsubakimoto, Maho [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa (Japan); Sugimura, Kazuro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan)

2013-11-01

Purpose: The purpose of this study was to compare diagnostic capabilities for assessment of recurrence in non-small cell lung cancer (NSCLC) patients by contrast-enhanced whole-body MRI (CE-WB-MRI) with and without CE-Quick 3D and double RF fat suppression technique (DFS), FDG-PET/CT and conventional radiological examinations. Materials and methods: A total of 134 pathologically proven and completely resected NSCLC patients (78 males, 56 females; mean age: 72 years) underwent FDG-PET/CT, CE-WB-MRI with and without Quick 3D and DFS at 3 T as well as conventional radiological examinations. The probability of recurrence was assessed with a 5-point scoring system on a per-patient basis, and final diagnosis was made by consensus between two readers. The capability for overall recurrence assessment by all the methods was compared by means of ROC analysis and their sensitivity, specificity and accuracy by means of McNemar's test. Results: Although areas under the curve did not show any significant differences, specificity (100%) and accuracy (95.5%) of CE-WB-MRI with CE-Quick 3D and DFS were significantly higher than those of FDG-PET/CT (specificity: 93.6%, p = 0.02; accuracy: 89.6%, p = 0.01) and conventional radiological examinations (specificity: 92.7%, p = 0.01; accuracy: 91.0%, p = 0.03). In addition, specificity of CE-WB-MRI without CE-Quick 3D and DFS (100%) was significantly higher than that of FDG-PET/CT (p = 0.02) and conventional radiological examinations (p = 0.01). Conclusion: Specificity and accuracy of CE-WB-MRI with CE-Quick 3D and DFS for assessment of recurrence in NSCLC patients are at least as high as, or higher than those of others.

SU-F-J-158: Respiratory Motion Resolved, Self-Gated 4D-MRI Using Rotating Cartesian K-Space Sampling

Energy Technology Data Exchange (ETDEWEB)

Han, F; Zhou, Z; Yang, Y; Sheng, K; Hu, P [UCLA School of Medicine, Los Angeles, CA (United States)

2016-06-15

Purpose: Dynamic MRI has been used to quantify respiratory motion of abdominal organs in radiation treatment planning. Many existing 4D-MRI methods based on 2D acquisitions suffer from limited slice resolution and additional stitching artifacts when evaluated in 3D{sup 1}. To address these issues, we developed a 4D-MRI (3D dynamic) technique with true 3D k-space encoding and respiratory motion self-gating. Methods: The 3D k-space was acquired using a Rotating Cartesian K-space (ROCK) pattern, where the Cartesian grid was reordered in a quasi-spiral fashion with each spiral arm rotated using golden angle{sup 2}. Each quasi-spiral arm started with the k-space center-line, which were used as self-gating{sup 3} signal for respiratory motion estimation. The acquired k-space data was then binned into 8 respiratory phases and the golden angle ensures a near-uniform k-space sampling in each phase. Finally, dynamic 3D images were reconstructed using the ESPIRiT technique{sup 4}. 4D-MRI was performed on 6 healthy volunteers, using the following parameters (bSSFP, Fat-Sat, TE/TR=2ms/4ms, matrix size=500×350×120, resolution=1×1×1.2mm, TA=5min, 8 respiratory phases). Supplemental 2D real-time images were acquired in 9 different planes. Dynamic locations of the diaphragm dome and left kidney were measured from both 4D and 2D images. The same protocol was also performed on a MRI-compatible motion phantom where the motion was programmed with different amplitude (10–30mm) and frequency (3–10/min). Results: High resolution 4D-MRI were obtained successfully in 5 minutes. Quantitative motion measurements from 4D-MRI agree with the ones from 2D CINE (<5% error). The 4D images are free of the stitching artifacts and their near-isotropic resolution facilitates 3D visualization and segmentation of abdominal organs such as the liver, kidney and pancreas. Conclusion: Our preliminary studies demonstrated a novel ROCK 4D-MRI technique with true 3D k-space encoding and respiratory

MRI of the fetal eyes: morphologic and biometric assessment for abnormal development with ultrasonographic and clinicopathologic correlation

International Nuclear Information System (INIS)

Robinson, Ashley J.; Blaser, Susan; Toi, Ants; Pantazi, Sophie; Chitayat, David; Keating, Sarah; Viero, Sandra; Ryan, Greg

2008-01-01

Currently ocular biometric measurements are defined by US and are measured from the orbital walls. These bony landmarks cannot be seen by MRI, and therefore these measurements cannot be directly applied. To define measurements of normal growth of the fetal eyes using MRI. Transorbital views were analyzed in 198 fetal MR examinations. The ocular diameter (OD) and interocular and binocular distances (IOD and BOD) were measured and were plotted against gestational age. Fetuses with abnormalities affecting the eyes were evaluated separately. Of 198 scans, 146 had suitable images, 35 of which were abnormal. Normal growth of BOD, IOD and OD were determined, and compared with the respective already established US data. Normal growth charts were derived from a cohort of 111 normal fetuses. Because the margins of the vitreous are inside the bony orbit, at the same gestational age measurements of the BOD and OD are always less than the corresponding measurements by US, and those of the IOD are always more. Normal growth charts for MRI can now be used to support suspected diagnoses of orbital and ocular pathologies and the syndromes that give rise to them, and many examples are demonstrated. (orig.)

Real-time 3-dimensional virtual reality navigation system with open MRI for breast-conserving surgery

International Nuclear Information System (INIS)

Tomikawa, Morimasa; Konishi, Kozo; Ieiri, Satoshi; Hong, Jaesung; Uemura, Munenori; Hashizume, Makoto; Shiotani, Satoko; Tokunaga, Eriko; Maehara, Yoshihiko

2011-01-01

We report here the early experiences using a real-time three-dimensional (3D) virtual reality navigation system with open magnetic resonance imaging (MRI) for breast-conserving surgery (BCS). Two patients with a non-palpable MRI-detected breast tumor underwent BCS under the guidance of the navigation system. An initial MRI for the breast tumor using skin-affixed markers was performed immediately prior to excision. A percutaneous intramammary dye marker was applied to delineate an excision line, and the computer software '3D Slicer' generated a real-time 3D virtual reality model of the tumor and the puncture needle in the breast. Under guidance by the navigation system, marking procedures were performed without any difficulties. Fiducial registration errors were 3.00 mm for patient no.1, and 4.07 mm for patient no.2. The real-time 3D virtual reality navigation system with open MRI is feasible for safe and accurate excision of non-palpable MRI-detected breast tumors. (author)

Is 3D MPRAGE better than the combination DIR/PSIR for cortical lesion detection at 3T MRI?

Science.gov (United States)

Nelson, Flavia; Poonawalla, Aziz; Datta, Sushmita; Wolinsky, Jerry; Narayana, Ponnada

2014-03-01

Based on the application of newer magnetic resonance imaging (MRI) acquisition sequences, the detection of cortical lesions (CL) in multiple sclerosis (MS) has significantly improved. Double inversion recovery (DIR) at 3T has increased the detection sensitivity and classification specificity when combined with phase sensitive inversion recovery (PSIR). Previous findings with 3D magnetization prepared rapid acquisition with gradient echo (MPRAGE) sequences, showed improved classification specificity of purely intracortical (IC) and mixed (MX) lesions, compared to the classification based on DIR/PSIR. Direct comparison between the detection of CL by 3D MPRAGE and by DIR/PSIR at 3T has not been evaluated. Eleven subjects were imaged on a 3T magnet. DIR/PSIR and 3D MPRAGE images were reviewed independently. Each image set was reviewed twice; only lesions detected on both sessions were scored. Review time per scan was ~5min for DIR/PSIR and ~15min for 3D MPRAGE. We identified 141 CL (62 IC+79 MX) based on DIR/PSIR images vs. 93 (38 IC+55 MX) based on MPRAGE from all eleven patients. MPRAGE under-detected the number of CL in seven cases and over-detected the number of CL in three, only one case had the same number of CL on both sets of images. Combination DIR/PSIR at 3T is superior to 3D MPRAGE for detection of cortical gray matter lesions in MS. The contrast-to-noise ratio of CL appears to be inferior on the MPRAGE images relative to DIR/PSIR. © 2013 Published by Elsevier B.V.

The developing role of knee MRI in musculo-skeletal radiology: the progression to 3-D imaging

International Nuclear Information System (INIS)

Kurmis, A.P.

2001-01-01

The purpose of this paper, following a comprehensive and systematic review of the available literature, is to provide both a historical record of the development of knee MRI and outline its progression to new 'state of the art' three dimensional reconstruction techniques. while preliminary work has been done to qualitatively- explore the application of 3D knee MR in controlled research settings the true clinical value of such applications has not yet been clearly established. lt was found that in the absence of valid research findings, much of the reported work in this area relied heavily on both anecdotal evidence and hypothetical expressions of likelihood. Much work must still be done to validate the reliability and clinical usefulness of this new diagnostic tool. In following with the reports of previous authors, the likely benefits of a 3-D computer reconstructed model of the knee include improved display of complex anatomical relationships, clarification of anatomical structures, clear demonstration of anatomy/pathology for those unfamiliar with tomographic or sectional images,and reduced examination time. Work has also suggested that 3-D MR may allow accurate pre-surgical classification of lesions while facilitating operative planning and real time intra-operative navigation. Other areas of cutting edge research also include applications toward surgical robotics, simulated surgical procedures, tele surgery, bone and prosthesis modeling, and virtual endoscopy/arthroscopy One of the more practical potential benefits of 3-D image displays may lie in assisting the radiologist to communicate the appearance of normal anatomy or pathological processes to other medical staff likely to be less familiar with the interpretation of routine two dimensional images. Such a method may also prove useful in aiding clinicians to convey their diagnoses and means of treatment to patients. It is hoped that this review will provide a base point from which future work can be

Neuropsychological deficits and morphological MRI brain scan abnormalities in apparently health non-encephalopathic patients with cirrhosis; A controlled Study

Energy Technology Data Exchange (ETDEWEB)

Moore, J.W.; De Lacey, G.; Dunk, A.A.; Sinclair, T.S.; Mowat, M.A.G.; Brunt, P.W. (Royal Infirmary, Aberdeen (United Kingdom)); Deans, H. (Aberdeen Univ. (UK). Dept. of Medical Physics (United Kingdom)); Crawford, J.R. (Aberdeen University Medical School (United Kingdom). Department of Psychology (United Kingdom)); Besson, J.A.O. (Aberdeen University Medical School (United Kingdom). Department of Mental Health (United Kingdom))

1989-11-01

By means of psychometric testing, we have determined the frequency of latent hepatic encephalopathy in a group of 19 cirrhotics with no clinical evidence of encephalopathy. Magnetic resonance imaging (MRI) of the brain was performed in order to determine whether morphological cerebral abnormalities were associated with latent encephalopathy. Nineteen age and educationally matched patient with normal liver function acted as controls. Significant differences (P < 0.05) between cirrhotics and controls were found in tests of short-term visual memory and speed of reaction to light (cirrhotics 326 ( 132 ms vs. controls 225 ) 36 ms), sound (cirrhotics 361 ( 152 ms vs. controls 236 ) 52 ms) and choice (cirrhotics 651 ( 190 ms vs. controls 406 ) 101 ms) stimuli (all values mean S.D.). Reitan trail test performance, however, was similar in both groups. ( Trail A: cirrhotics 43 ( 19 s vs. controls 35 ) 13 s; Trail B: cirrhotics 105 ( 66 s vs. controls 93 ) 36 s.) In patients with cirrhosis, MRI revealed statistically significant increases in the maximum fissure width of right frontal sulci, light and left parietal sulci, inter-hemispheric fissure width and in bicaudafe index. These changes, indicating cerebral atrophy, were largely confined to alcoholics. There was poor correlation between measurements of cerebral morphology and neuropsychological performance, only 10% of associations achieving statistical significance. (author). 2 refs.; 3 figs.; 5 tabs.

Time-resolved 3D pulmonary perfusion MRI: comparison of different k-space acquisition strategies at 1.5 and 3 T.

Science.gov (United States)

Attenberger, Ulrike I; Ingrisch, Michael; Dietrich, Olaf; Herrmann, Karin; Nikolaou, Konstantin; Reiser, Maximilian F; Schönberg, Stefan O; Fink, Christian

2009-09-01

Time-resolved pulmonary perfusion MRI requires both high temporal and spatial resolution, which can be achieved by using several nonconventional k-space acquisition techniques. The aim of this study is to compare the image quality of time-resolved 3D pulmonary perfusion MRI with different k-space acquisition techniques in healthy volunteers at 1.5 and 3 T. Ten healthy volunteers underwent contrast-enhanced time-resolved 3D pulmonary MRI on 1.5 and 3 T using the following k-space acquisition techniques: (a) generalized autocalibrating partial parallel acquisition (GRAPPA) with an internal acquisition of reference lines (IRS), (b) GRAPPA with a single "external" acquisition of reference lines (ERS) before the measurement, and (c) a combination of GRAPPA with an internal acquisition of reference lines and view sharing (VS). The spatial resolution was kept constant at both field strengths to exclusively evaluate the influences of the temporal resolution achieved with the different k-space sampling techniques on image quality. The temporal resolutions were 2.11 seconds IRS, 1.31 seconds ERS, and 1.07 VS at 1.5 T and 2.04 seconds IRS, 1.30 seconds ERS, and 1.19 seconds VS at 3 T.Image quality was rated by 2 independent radiologists with regard to signal intensity, perfusion homogeneity, artifacts (eg, wrap around, noise), and visualization of pulmonary vessels using a 3 point scale (1 = nondiagnostic, 2 = moderate, 3 = good). Furthermore, the signal-to-noise ratio in the lungs was assessed. At 1.5 T the lowest image quality (sum score: 154) was observed for the ERS technique and the highest quality for the VS technique (sum score: 201). In contrast, at 3 T images acquired with VS were hampered by strong artifacts and image quality was rated significantly inferior (sum score: 137) compared with IRS (sum score: 180) and ERS (sum score: 174). Comparing 1.5 and 3 T, in particular the overall rating of the IRS technique (sum score: 180) was very similar at both field

T1rho, T{sub 2} and focal knee cartilage abnormalities in physically active and sedentary healthy subjects versus early OA patients - a 3.0-Tesla MRI study

Energy Technology Data Exchange (ETDEWEB)

Stahl, Robert [University of California, San Francisco, Musculoskeletal and Quantitative Imaging Group, Department of Radiology, San Francisco, CA (United States); University Hospitals-Campus Grosshadern, Ludwig Maximilians University of Munich, Department of Clinical Radiology, Munich (Germany); Luke, Anthony; Ma, C.B. [University of California, San Francisco, Department of Orthopedic Surgery, San Francisco, CA (United States); Li, Xiaojuan; Carballido-Gamio, Julio; Majumdar, Sharmila; Link, Thomas M. [University of California, San Francisco, Musculoskeletal and Quantitative Imaging Group, Department of Radiology, San Francisco, CA (United States)

2009-01-15

(1) To assess the degree of focal cartilage abnormalities in physically active and sedentary healthy subjects as well as in patients with early osteoarthritis (OA). (2) To determine the diagnostic value of T2 and T1rho measurements in identifying asymptomatic physically active subjects with focal cartilage lesions. Thirteen asymptomatic physically active subjects, 7 asymptomatic sedentary subjects, and 17 patients with mild OA underwent 3.0-T MRI of the knee joint. T1rho and T2 values, cartilage volume and thickness, as well as the WORMS scores were obtained. Nine out of 13 active healthy subjects had focal cartilage abnormalities. T1rho and T2 values in active subjects with and without focal cartilage abnormalities differed significantly (p<0.05). T1rho and T2 values were significantly higher (p<0.05) in early OA patients compared to healthy subjects. T1rho measurements were superior to T2 in differentiating OA patients from healthy subjects, yet T1rho was moderately age-dependent. (1) Active subjects showed a high prevalence of focal cartilage abnormalities and (2) active subjects with and without focal cartilage abnormalities had different T1rho and T2 composition of cartilage. Thus, T1rho and T2 could be a parameter suited to identify active healthy subjects at higher risk for developing cartilage pathology. (orig.)

Low Cost, High-Throughput 3-D Pulmonary Imager Using Hyperpolarized Contrast Agents and Low-Field MRI

Science.gov (United States)

2017-10-01

greater gas polarizations and production amounts/ throughputs- benefiting in particular from the advent of com- pact, high-power, relatively low- cost ...Award Number: W81XWH-15-1-0271 TITLE: Low- Cost , High-Throughput 3-D Pulmonary Imager Using Hyperpolarized Contrast Agents and Low-Field MRI...DISTRIBUTION STATEMENT: Approved for Public Release; Distribution Unlimited The views, opinions and/or findings contained in this report are those of the

Parenchymal abnormalities associated with developmental venous anomalies

Energy Technology Data Exchange (ETDEWEB)

San Millan Ruiz, Diego; Gailloud, Philippe [Johns Hopkins Hospital, Division of Interventional Neuroradiology, Baltimore, MD (United States); Delavelle, Jacqueline [Geneva University Hospital, Neuroradiology Section, Department of Radiology and Medical Informatics, Geneva (Switzerland); Yilmaz, Hasan; Ruefenacht, Daniel A. [Geneva University Hospital, Section of Interventional Neuroradiology, Department of Clinical Neurosciences, Geneva (Switzerland); Piovan, Enrico; Bertramello, Alberto; Pizzini, Francesca [Verona City Hospital, Service of Neuroradiology, Verona (Italy)

2007-12-15

To report a retrospective series of 84 cerebral developmental venous anomalies (DVAs), focusing on associated parenchymal abnormalities within the drainage territory of the DVA. DVAs were identified during routine diagnostic radiological work-up based on magnetic resonance imaging (MRI) (60 cases), computed tomography (CT) (62 cases) or both (36 cases). Regional parenchymal modifications within the drainage territory of the DVA, such as cortical or subcortical atrophy, white matter density or signal alterations, dystrophic calcifications, presence of haemorrhage or a cavernous-like vascular malformation (CVM), were noted. A stenosis of the collecting vein of the DVA was also sought for. Brain abnormalities within the drainage territory of a DVA were encountered in 65.4% of the cases. Locoregional brain atrophy occurred in 29.7% of the cases, followed by white matter lesions in 28.3% of MRI investigations and 19.3% of CT investigations, CVMs in 13.3% of MRI investigations and dystrophic calcification in 9.6% of CT investigations. An intracranial haemorrhage possibly related to a DVA occurred in 2.4% cases, and a stenosis on the collecting vein was documented in 13.1% of cases. Parenchymal abnormalities were identified for all DVA sizes. Brain parenchymal abnormalities were associated with DVAs in close to two thirds of the cases evaluated. These abnormalities are thought to occur secondarily, likely during post-natal life, as a result of chronic venous hypertension. Outflow obstruction, progressive thickening of the walls of the DVA and their morphological organization into a venous convergence zone are thought to contribute to the development of venous hypertension in DVA. (orig.)

Diagnositc value of 3D-gradient echo dynamic contrast enhanced MRI in breast cancer

Energy Technology Data Exchange (ETDEWEB)

Yang, Ik; Chung, Soo Young; Park, Hai Jung; Lee, Yul; Chung, Bong Wha; Shim, Jeong Won [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

1997-10-01

To assess the usefulness of 3D-gradient echo dynamic contrast enhanced MRI (3D-DMRI) in the diagnosis of breast cancer and to determine the most useful parameter for this diagnosis. Using a 1.0T MR unit, (Magnetom, Siemens, Erlaugen, Germany), 3D-DMRI (TR/TE=3D30/12) with Gd-DTPA was performed in 38 cases of breast cancer, 22 of fibroadenoma, and in three normal volunteers. We retrospectively evaluated the findings according to the speed on dynamic study and maximal amount of contrast enhancement during the delayed phase;we calculated the contrast index and morphology of the cancers and compared diagnostic accuracy among these three diagnostic parameters. On conventional spin-echo T1-and T2-weighted images, there was no significant difference of signal intensity between benign fibroadenoma and breast carcinoma. Rapid contrast enhancement (within one minute) was noted in 35 breast cancer lesions (92.1%), but relatively low and slow contrast enhancement (after five minutes) was noted in three such lesions (7.9%). Gradual contrast enhancement was noted in 21 lesions of fibroadenoma(95.5%), but a moderate degree of rapid contrast enhancement (from three to five minutes) was noted in the other case (7.9%). of On the delayed enhanced phase of 3D-DMRI, the maximal amount of contrast enhancement showed no significant difference between fibroadenoma and cancer. On 3D-DMRI, an irregular, spiculated border, with high contrast enhancement was noted in all cases of breast cancer, in particular, irregular thick peripheral contrast enhancement with central necrosis was noted 11cases(28.9%). For the diagnosis of breast cancer, 3D-DMRI is a useful technique. Among the diagnostic criteria of speed, maximal amount of contrast enhancement and morphology, morphologic change after contrast enhancement study was the most useful diagnostic parameter.=20.

Diagnositc value of 3D-gradient echo dynamic contrast enhanced MRI in breast cancer

International Nuclear Information System (INIS)

Yang, Ik; Chung, Soo Young; Park, Hai Jung; Lee, Yul; Chung, Bong Wha; Shim, Jeong Won

1997-01-01

To assess the usefulness of 3D-gradient echo dynamic contrast enhanced MRI (3D-DMRI) in the diagnosis of breast cancer and to determine the most useful parameter for this diagnosis. Using a 1.0T MR unit, (Magnetom, Siemens, Erlaugen, Germany), 3D-DMRI (TR/TE=3D30/12) with Gd-DTPA was performed in 38 cases of breast cancer, 22 of fibroadenoma, and in three normal volunteers. We retrospectively evaluated the findings according to the speed on dynamic study and maximal amount of contrast enhancement during the delayed phase;we calculated the contrast index and morphology of the cancers and compared diagnostic accuracy among these three diagnostic parameters. On conventional spin-echo T1-and T2-weighted images, there was no significant difference of signal intensity between benign fibroadenoma and breast carcinoma. Rapid contrast enhancement (within one minute) was noted in 35 breast cancer lesions (92.1%), but relatively low and slow contrast enhancement (after five minutes) was noted in three such lesions (7.9%). Gradual contrast enhancement was noted in 21 lesions of fibroadenoma(95.5%), but a moderate degree of rapid contrast enhancement (from three to five minutes) was noted in the other case (7.9%). of On the delayed enhanced phase of 3D-DMRI, the maximal amount of contrast enhancement showed no significant difference between fibroadenoma and cancer. On 3D-DMRI, an irregular, spiculated border, with high contrast enhancement was noted in all cases of breast cancer, in particular, irregular thick peripheral contrast enhancement with central necrosis was noted 11cases(28.9%). For the diagnosis of breast cancer, 3D-DMRI is a useful technique. Among the diagnostic criteria of speed, maximal amount of contrast enhancement and morphology, morphologic change after contrast enhancement study was the most useful diagnostic parameter.=20

Initial clinical assessment of CT-MRI image fusion software in localization of the prostate for 3D conformal radiation therapy

International Nuclear Information System (INIS)

Kagawa, Kazufumi; Lee, W. Robert; Schultheiss, Timothy E.; Hunt, Margie A.; Shaer, Andrew H.; Hanks, Gerald E.

1997-01-01

Purpose: To assess the utility of image fusion software and compare MRI prostate localization with CT localization in patients undergoing 3D conformal radiation therapy of prostate cancer. Materials and Methods: After a phantom study was performed to ensure the accuracy of image fusion procedure, 22 prostate cancer patients had CT and MRI studies before the start of radiotherapy. Immobilization casts used during radiation treatment were also used for both imaging studies. After the clinical target volume (CTV) (prostate or prostate + seminal vesicles) was defined on CT, slices from the MRI study were reconstructed to precisely match the CT slices by identifying three common bony landmarks on each study. The CTV was separately defined on the matched MRI slices. Data related to the size and location of the prostate were compared between CT and MRI. The spatial relationship between the tip of urethrogram cone on CT and prostate apex seen on MRI was also estimated. Results: The phantom study showed the registration discrepancies between CT and MRI smaller than 1.0 mm in any pair in comparison. The patient study showed a mean image registration error of 0.9 (± 0.6) mm. The average prostate volume was 63.0 (± 25.8) cm 3 and 50.9 (± 22.9) cm 3 determined by CT and MRI, respectively. The difference in prostate location with the two studies usually differed at the base and at the apex of the prostate. On the transverse MRI, the prostate apex was situated 7.1 (± 4.5) mm dorsal and 15.1 (± 4.0) mm cephalad to the tip of urethrogram cone. Conclusions: CT-MRI image fusion study made it possible to compare the two modalities directly. MRI localization of the prostate is more accurate than CT, and indicates the distance from cone to apex is 15 mm. CT-MRI image fusion technique provides valuable supplements to CT technology for more precise targeting of the prostate cancer

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

spondylolysis, 2D MRI is still very good at detecting spondylolysis while remaining sensitive for detection of alternative diagnoses such as disc abnormalities and pars stress reaction. The data suggest that standard 2D MRI sequences should not be entirely replaced by a volumetric T2-weighted 3D sequence (despite promising features of rapid acquisition time, increased spatial resolution, and reconstruction capability). © 2016 The Author(s).

Neurological abnormalities predict disability

DEFF Research Database (Denmark)

Poggesi, Anna; Gouw, Alida; van der Flier, Wiesje

2014-01-01

To investigate the role of neurological abnormalities and magnetic resonance imaging (MRI) lesions in predicting global functional decline in a cohort of initially independent-living elderly subjects. The Leukoaraiosis And DISability (LADIS) Study, involving 11 European centres, was primarily aimed...... at evaluating age-related white matter changes (ARWMC) as an independent predictor of the transition to disability (according to Instrumental Activities of Daily Living scale) or death in independent elderly subjects that were followed up for 3 years. At baseline, a standardized neurological examination.......0 years, 45 % males), 327 (51.7 %) presented at the initial visit with ≥1 neurological abnormality and 242 (38 %) reached the main study outcome. Cox regression analyses, adjusting for MRI features and other determinants of functional decline, showed that the baseline presence of any neurological...

Neurologic abnormalities in murderers.

Science.gov (United States)

Blake, P Y; Pincus, J H; Buckner, C

1995-09-01

Thirty-one individuals awaiting trial or sentencing for murder or undergoing an appeal process requested a neurologic examination through legal counsel. We attempted in each instance to obtain EEG, MRI or CT, and neuropsychological testing. Neurologic examination revealed evidence of "frontal" dysfunction in 20 (64.5%). There were symptoms or some other evidence of temporal lobe abnormality in nine (29%). We made a specific neurologic diagnosis in 20 individuals (64.5%), including borderline or full mental retardation (9) and cerebral palsy (2), among others. Neuropsychological testing revealed abnormalities in all subjects tested. There were EEG abnormalities in eight of the 20 subjects tested, consisting mainly of bilateral sharp waves with slowing. There were MRI or CT abnormalities in nine of the 19 subjects tested, consisting primarily of atrophy and white matter changes. Psychiatric diagnoses included paranoid schizophrenia (8), dissociative disorder (4), and depression (9). Virtually all subjects had paranoid ideas and misunderstood social situations. There was a documented history of profound, protracted physical abuse in 26 (83.8%) and of sexual abuse in 10 (32.3%). It is likely that prolonged, severe physical abuse, paranoia, and neurologic brain dysfunction interact to form the matrix of violent behavior.

Imaging of the Achilles tendon in spondyloarthritis: a comparison of ultrasound and conventional, short and ultrashort echo time MRI with and without intravenous contrast

International Nuclear Information System (INIS)

Hodgson, R.J.; Emery, P.; Grainger, A.J.; O'Connor, P.J.; Evans, R.; Coates, L.; Marzo-Ortega, H.; Helliwell, P.; McGonagle, D.; Robson, M.D.

2011-01-01

To compare conventional MRI, ultrashort echo time MRI and ultrasound for assessing the extent of tendon abnormalities in spondyloarthritis. 25 patients with spondyloarthritis and Achilles symptoms were studied with MRI and ultrasound. MR images of the Achilles tendon were acquired using T1-weighted spin echo, gradient echo and ultrashort echo time (UTE) sequences with echo times (TE) between 0.07 and 16 ms, before and after intravenous contrast medium. Greyscale and power Doppler ultrasound were also performed. The craniocaudal extent of imaging abnormalities measured by a consultant musculoskeletal radiologist was compared between the different techniques. Abnormalities were most extensive on spoiled gradient echo images with TE=2 ms. Contrast enhancement after intravenous gadolinium was greatest on the UTE images (TE=0.07 ms). Fewer abnormalities were demonstrated using unenhanced UTE. Abnormalities were more extensive on MRI than ultrasound. Contrast enhancement was more extensive than power Doppler signal. 3D spoiled gradient echo images with an echo time of 2 ms demonstrate more extensive tendon abnormalities than the other techniques in spondyloarthritis. Abnormalities of vascularity are best demonstrated on enhanced ultrashort echo time images. (orig.)

Low-Cost, High-Throughput 3-D Pulmonary Imager Using Hyperpolarized Contrast Agents and Low-Field MRI

Science.gov (United States)

2017-10-01

low- cost and high-throughput was a key element proposed for this project, which we believe will be of significant benefit to the patients suffering...Award Number: W81XWH-15-1-0272 TITLE: Low- Cost , High-Throughput 3-D Pulmonary Imager Using Hyperpolarized Contrast Agents and Low-Field MRI...STATEMENT: Approved for Public Release; Distribution Unlimited The views, opinions and/or findings contained in this report are those of the author(s

Diagnostic value of MRI in cerebrovascular disease

Energy Technology Data Exchange (ETDEWEB)

Sone, Reiko; Uchiyama, Shinichiro; Kobayashi, Itsuro; Maruyama, Shoichi; Kakinoki, Yoshio; Ono, Yuko; Kobayashi, Naotoshi (Tokyo Women' s Medical Coll. (Japan))

1989-06-01

Thirty-four patients with cerebrovascular disease were studied with both magnetic resonance imaging (MRI) and cranial computed tomography (CT). They were 29 cerebral or cerebreller infarction and 5 cerebral bleeding. From the clinical symptoms, supratentorial lesions were suspected in 17 patients. Areas of abnormal density on CT were detected in all these patients. Areas of abnormal intensity on MRI were detected in 14 patients. Based on the infratentorial MRI, in four patients who have not shown any abnormal symptoms asyptomatic small lesions were detected. Infratentorial lesions were suspected in 17 patients. Areas of abnormal density on CT were detected in 6 patients (35%), while areas of abnormal intensity on MRI were detected in 13 patients (77%). Abnormal regions, which failed to be demonstrated on MRI were enhanced with Gd-DTPA in a patient with midbrain infarction. In a patient with Wallenberg's syndrome, area of abnormal intensity shown by MRI was consistent with lateral medullary infarct identified by autopsy. The results indicate that MRI is more useful than CT for detecting brainstem lesions in stroke. (author).

MRI features of meningeal metastasis from lung cancer

International Nuclear Information System (INIS)

Luo Xuemao; Long Wansheng; Jin Zhifa; Hu Maoqing; Mai Xuyu

2009-01-01

Objective: To investigate the pathway and MRI findings of meningeal metastasis original from lung cancer. Methods: 44 cases with cerebro-spinal meningeal metastasis original from lung cancer proven by clinical and pathology were retrospectively reviewed. All cases undergone plain MRI scan and Gd-DTPA enhanced MRI scan on brain and/or spine. Results: MRI plain scan indicated 28 cases with brain metastases, 3 cases with meningeal nodosity or irregularly patchy abnormal signal, 1 case with nodule in left cavernous sinus, 10 cases with abnormal signal in spine, 2 cases with abnormal signal in spinal dura mater. 34 cases with cerebro meningeal metastases were found in MRI enhancement scan. Among them, 11 cases displayed cerebral dura mater-arachnoid enhancement, 17 cases revealed cerebral pia mater-arachnoid enhancement and 6 cases with mixed typed enhancement. Osteoclasia in skull was found in 4 cases, spinal metastasis was revealed in 17 cases, and patchy abnormal enhancement in spinal dura mater was showed in 12 cases. Conclusion: Hematogenous metastasis is a main route of meningeal metastasis caused by lung cancer and enhanced MRI scan is of important diagnostic value. (authors)

Congenital tracheobiliary fistula diagnosed with contrast-enhanced CT and 3-D reformation

Energy Technology Data Exchange (ETDEWEB)

Chawla, Soni C. [Olive View-UCLA Medical Center, Department of Radiological Sciences, Sylmar, CA (United States); University of California, Los Angeles (UCLA), Department of Radiological Sciences, Sylmar, CA (United States); Jha, Priyanka; Breiman, Richard; Gooding, Charles [University of California, San Francisco (UCSF), Department of Radiological Sciences, San Francisco, CA (United States); Farmer, Diana [University of California, San Francisco (UCSF), Department of Pediatric Surgery, San Francisco, CA (United States)

2008-09-15

Congenital tracheobiliary fistula (CTBF) is a rare malformation. So far 24 cases have been reported in the English language literature. The imaging techniques used in diagnosis have been bronchography, fistulography, cholangiography, hepatobiliary nuclear imaging and MRI. We report a newborn patient who presented with right lung consolidation and biliptysis. The radiographic diagnosis of tracheobiliary fistula was made on multidetector CT scan of the chest and abdomen. Multiple 3-D volume-rendered reformations were performed. An abnormal air-filled tract was seen connecting the posteroinferior aspect of the carina and left biliary system, which was successfully treated surgically. (orig.)

3-D MRI for lumbar degenerative diseases

International Nuclear Information System (INIS)

Aota, Yoichi; Kumano, Kiyoshi; Hirabayashi, Shigeru; Ogawa, Yu; Izumi, Yasujiro; Yoshikawa, Koki; Yamazaki, Tatsuo.

1993-01-01

Three-dimensional (3-D) magnetic resonance (MR) images obtained from 10 patients with lumbar degenerative diseases were retrospectively reviewed to determine how far 3-D MR imaging is capable of demonstrating nerve roots. In 8 of the 10 patients, the area up to the dorsal root ganglion was visualized on 3-D MR images. Thus, it is capable of detecting a wide area of nerve roots, thereby allowing the determination of running of nerve root, and size and location of dorsal root ganglion. In delineating the area from the dural canal to root cyst, 3-D MR imaging was equal to conventional myelography. The former was superior to the latter in detecting the positional relation between the degenerative intervertebral disc and the nerve root, and herniation-compressed root cyst. In 3 of 9 patients who presented with root symptoms, disturbed nerve roots were of high signal on 3-D MR images. This may suggest that it has the potential for selectively detecting root nerves associated with clinical manifestations. (N.K.)

Abnormal baseline brain activity in Parkinson's disease with and without REM sleep behavior disorder: A resting-state functional MRI study.

Science.gov (United States)

Li, Dan; Huang, Peiyu; Zang, Yufeng; Lou, Yuting; Cen, Zhidong; Gu, Quanquan; Xuan, Min; Xie, Fei; Ouyang, Zhiyuan; Wang, Bo; Zhang, Minming; Luo, Wei

2017-09-01

To investigate the differences in spontaneous brain activity between Parkinson's disease (PD) patients with rapid eye movement sleep behavior disorder (RBD), PD patients without RBD, and normal controls, which may shed new light on the neural mechanism of RBD. Eighteen PD patients with RBD, 16 patients without RBD, and 19 age- and gender-matched normal controls underwent clinical assessment and functional magnetic resonance imaging (fMRI) with a 3.0T scanner. Resting-state fMRI scans were collected using an echo planar imaging sequence. Amplitude of low-frequency fluctuations (ALFF) were calculated to measure spontaneous brain activity in each subject. Compared with PD patients without RBD, patients with RBD exhibited significantly decreased ALFF values (P abnormalities. Our findings provide additional insight into the neural mechanism of RBD and may drive future research to develop better treatment. 3 Technical Efficacy: Stage 3 J. MAGN. RESON. IMAGING 2017;46:697-703. © 2016 International Society for Magnetic Resonance in Medicine.

A spatiotemporal-based scheme for efficient registration-based segmentation of thoracic 4-D MRI.

Science.gov (United States)

Yang, Y; Van Reeth, E; Poh, C L; Tan, C H; Tham, I W K

2014-05-01

Dynamic three-dimensional (3-D) (four-dimensional, 4-D) magnetic resonance (MR) imaging is gaining importance in the study of pulmonary motion for respiratory diseases and pulmonary tumor motion for radiotherapy. To perform quantitative analysis using 4-D MR images, segmentation of anatomical structures such as the lung and pulmonary tumor is required. Manual segmentation of entire thoracic 4-D MRI data that typically contains many 3-D volumes acquired over several breathing cycles is extremely tedious, time consuming, and suffers high user variability. This requires the development of new automated segmentation schemes for 4-D MRI data segmentation. Registration-based segmentation technique that uses automatic registration methods for segmentation has been shown to be an accurate method to segment structures for 4-D data series. However, directly applying registration-based segmentation to segment 4-D MRI series lacks efficiency. Here we propose an automated 4-D registration-based segmentation scheme that is based on spatiotemporal information for the segmentation of thoracic 4-D MR lung images. The proposed scheme saved up to 95% of computation amount while achieving comparable accurate segmentations compared to directly applying registration-based segmentation to 4-D dataset. The scheme facilitates rapid 3-D/4-D visualization of the lung and tumor motion and potentially the tracking of tumor during radiation delivery.