bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intracoronary MR imaging using a 0.014‐inch MR imaging‐guidewire: Toward MRI‐guided coronary interventions
Authors: Qiu Bensheng , Gao Fabao , Karmarkar Parag , Atalar Ergin , Yang Xiaoming 
Published: July 2008

AbstractPurposeTo validate the feasibility of using a newly designed MR imaging‐guidewire (MRIG) to guide angioplasty balloon placement in coronary arteries.Materials and MethodsA custom gold/sliver/Nitinol/MP35N‐based, 0.014‐inch MRIG was manufactured. To test its mechanical performance we used the new MRIG to catheterize the left coronary arteries of three dogs under x‐ray fluoroscopy. To further validate the feasibility of using the MRIG to generate intracoronary MR imaging, we positioned the MRIG, along with a dilation‐perfusion balloon catheter, into the left coronary arteries of an additional three dogs. Longitudinal and four‐chamber views of cine cardiac MR images were obtained using a fast gradient recalled echo (FGRE) sequence (TR/TE/FA = 5.2 msec/1.6 msec/20°, field of view [FOV] = 32 × 32 cm, thickness = 5 mm, space = 2 mm, matrix = 256 × 160, number of excites [NEX] = 0.5, and bandwidth [BW] = 32 kHz). Then three‐dimensional (3D) MR coronary angiography of the left coronary arteries was obtained using a fast imaging employing steady‐state acquisition (FIESTA) sequence. We subsequently used the MRIG, at a receive‐only mode, to generate intracoronary MR images using FGRE (TR/TE/FA = 7.2 msec/3.5 msec/20°, FOV = 18 × 18cm, thickness = 3 mm, space = 0.5 mm, matrix = 256 × 256, NEX = 0.5, and BW = 32 kHz).ResultsIn all six animals the left main coronary arteries were successfully catheterized. 3D MR imaging displayed left coronary artery branches. Intracoronary MR imaging demonstrated the inflated balloons as a “train track” or a bright, thick ring at different views.ConclusionThis study demonstrates the potential of using this newly designed gold/sliver/Nitinol/MP35N‐based, 0.014‐inch MRIG to catheterize coronary arteries and, thus, generate intracoronary MR imaging with balloon inflation. J. Magn. Reson. Imaging 2008;28:515–518. © 2008 Wiley‐Liss, Inc.
Metabolite signature of developmental foregut cyst on in vivo and in vitro 1H MR spectroscopy
Authors: Santhosh Kannath , Thomas Bejoy , Varma Luxmi , Sandhyamany S. , Kesavadas Chandrasekharan , Appukuttan P.S. , Srinivas G. , Gupta Arun Kumar , Kapilamoorthy T.R. , Unnikrishnan M. 
Published: July 2008

AbstractForegut duplication cysts are developmental anomalies of the bronchopulmonary foregut and are common cystic lesions of the mediastinum. We describe a case of mediastinal foregut duplication cyst with in vivo 1H MR spectroscopy on a 1.5T magnet showing a large metabolite peak at 2.02 ppm, attributable to N‐acetylated compounds, in addition to a smaller peak at 1.33 ppm, considered to represent lipids. In vitro NMR spectroscopy (7.05T) of cyst fluid confirmed the presence of these peaks. In addition, a broad multiplet centered at 3.7 ppm, possibly from various protons of the hexose ring system, was also noted. Chemical analysis of the cyst fluid demonstrated the presence of N‐acetylhexosamines, proteins, and lipids. Again, in vitro spectra of pure samples of N‐acetylglucosamine and N‐acetylgalactosamine were obtained for comparison, which better resolved the N‐acetyl peak and the peaks at 3.7 ppm. The mucus secreted by respiratory epithelium and the mucous glands of the foregut cysts contains glycoproteins that have N‐acetylhexosamines as components and lipid breakdown products that are thought to contribute to the observed spectrum. This information might be useful in predicting the cyst content and, in turn, the lining of the epithelium and the glandular elements. J. Magn. Reson. Imaging 2008;28:493–496. © 2008 Wiley‐Liss, Inc.
Simultaneous estimation of tongue volume and fat fraction using IDEAL‐FSE
Authors: Humbert Ianessa A. , Reeder Scott B. , Porcaro Eva J. , Kays Stephanie A. , Brittain Jean H. , Robbins JoAnne 
Published: July 2008

AbstractPurposeTo determine whether high‐resolution, high signal‐to‐noise ratio (SNR) images of the tongue acquired with IDEAL‐FSE (iterative decomposition of water and fat with echo asymmetry and least squares estimation) will provide comparable volumetric measures to conventional nonfat‐suppressed FSE imaging and to determine the feasibility of estimating the proportion of lingual fat in adults using IDEAL‐FSE imaging.Materials and MethodsHealthy volunteers underwent magnetic resonance imaging of the tongue using both IDEAL‐FSE and conventional FSE sequences. The tongue was manually outlined to derive both volumetric and fat fraction measures. Intraclass correlation coefficients (ICCs) were computed for intrarater measurement reliability and Spearman's rank correlation tested the relationship between IDEAL‐FSE and conventional volumetric measures of the tongue.ResultsIDEAL‐FSE imaging yielded almost identical volumetric measures to that of conventional FSE imaging in the same amount of scan time (IDEAL‐FSE mean 64.1 cm3; conventional mean 63.3 cm3; r = 0.988, P ≤ 0.01). The average fat signal fraction across participants was 26.5%. Intrarater reliability was excellent for all measures (ICC ≥ 0.92).ConclusionOur results indicate that IDEAL‐FSE provided similar lingual volume estimates to conventional FSE imaging obtained in both the current and previous studies. IDEAL‐FSE measures of lingual fat composition may be useful in studies that aim to increase lingual muscle strength and volume in swallowing and speech‐disordered populations. J. Magn. Reson. Imaging 2008;28:504–508. © 2008 Wiley‐Liss, Inc.
MR‐guided direct arthrography of the hip
Authors: Graves Martin J. , Wakely Suzanne , Bearcroft Philip W. , Black Richard T. , van Rooyen Elzare , Soh Edmund , Lomas David J. 
Published: July 2008

AbstractPurposeTo develop an MR‐guided technique for direct magnetic resonance arthrography (DMRA) of the hip using a conventional 1.5 Tesla (T) MRI scanner.Materials and MethodsInteractive versions of standard single‐shot fast spin echo, coherent gradient echo, and fully balanced steady‐state free precession sequences were developed, together with the ability to operate the scanner from within the magnet room. Initial optimization was performed using ex vivo animal joints. After informed consent, five patients underwent DMRA using dilute gadolinium as the contrast medium.ResultsThe procedure was successful in all five patients and diagnostic quality MR arthrography studies were obtained in all cases. The time taken from the initial placement of skin marker to the introduction of contrast medium reduced with successive patients: 26, 22, and 19 min with the final two studies taking 13 min each.ConclusionThis work demonstrates the feasibility of performing DMRA using MR guidance, avoiding the need for X‐ray fluoroscopy facilities but exploiting the available imaging performance of a high‐field closed‐bore MR system. The use of an in room control and display system together with interactive fluoroscopic imaging sequences simplifies the positioning of the needle and allows rapid confirmation of an intra‐articular injection. J. Magn. Reson. Imaging 2008;28:462–465. © 2008 Wiley‐Liss, Inc.
MR susceptibility weighted imaging (SWI) complements conventional contrast enhanced T1 weighted MRI in characterizing brain abnormalities of Sturge‐Weber Syndrome
Authors: Hu Jiani , Yu Yingjian , Juhasz Csaba , Kou Zhifeng , Xuan Yang , Latif Zahid , Kudo Kohsuke , Chugani Harry T. , Haacke E. Mark 
Published: July 2008

AbstractPurposeTo evaluate the efficacy of susceptibility weighted imaging (SWI) in comparison to standard T1 weighted postgadolinium contrast (T1‐Gd) MRI in patients with Sturge‐Weber Syndrome (SWS).Materials and MethodsTwelve children (mean age, 5.6 years) with the diagnosis of SWS and unilateral hemispheric involvement were recruited prospectively and examined with high resolution three dimensional SWI and conventional T1‐Gd. Both SWI and T1‐Gd images were evaluated using a four‐grade scoring system according to six types of imaging findings (enlargement of transmedullary veins, periventricular veins, and choroid plexus, as well as leptomeningeal abnormality, cortical gyriform abnormality, and gray matter/white matter junctional abnormality). The scores of SWI versus T1‐Gd images were then compared for each type of abnormality.ResultsSWI was superior to T1‐Gd in identifying the enlarged transmedullary veins (P = 0.0020), abnormal periventricular veins (P = 0.0078), cortical gyriform abnormalities (P = 0.0020), and gray matter/white matter junction abnormalities (P = 0.0078). Conversely, T1‐Gd was better than SWI in identifying enlarged choroid plexus (P = 0.0050) and leptomeningeal abnormalities (P = 0.0050).ConclusionSWI can provide useful and unique information complementary to conventional contrast enhanced T1 weighted MRI for characterizing SWS. Therefore, SWI should be integrated into routine clinical MRI protocols for suspected SWS. J. Magn. Reson. Imaging 2008;28:300–307. © 2008 Wiley‐Liss, Inc.
Quantitative assessment of bone marrow edema‐like lesion and overlying cartilage in knees with osteoarthritis and anterior cruciate ligament tear using MR imaging and spectroscopic imaging at 3 Tesla
Authors: Li Xiaojuan , Ma Benjamin C. , Bolbos Radu I. , Stahl Robert , Lozano Jesus , Zuo Jin , Lin Katrina , Link Thomas M. , Safran Marc , Majumdar Sharmila 
Published: July 2008

AbstractPurposeTo quantitatively assess bone marrow edema‐like lesion (BMEL) and the overlying cartilage in osteoarthritis (OA) or anterior cruciate ligament (ACL)‐injured knees using magnetic resonance imaging (MRI) and spectroscopic imaging (MRSI).Materials and MethodsEight healthy controls and 30 patients with OA and other injuries who showed BMEL were scanned at 3.0T. A regression model was constructed to automatically calculate the volume of BMEL. Normalized T1ρ z‐scores were calculated within BMEL‐overlying cartilage. Three‐dimensional (3D) MRSI was acquired in the BMEL and surrounding bone marrow.ResultsThe mean T1ρ z‐score was significantly higher in BMEL‐overlying cartilage than that in surrounding cartilage in the lateral tibia of patients with ACL tears (P < 0.001). Significantly elevated water and unsaturated lipids, and decreased saturated lipids were observed in BMEL. The volume of elevated water correlated with the volume of BMEL. Water content was significantly higher within BMEL than that outside BMEL. The unsaturation index outside BMEL was significantly higher in patients with ACL tears than that in OA.Conclusion3D MRSI and T1ρ mapping provide tools to quantitatively evaluate BMEL in OA and knee injury. This may allow us to better understand pathophysiology and evolution of injuries and degenerative conditions of the knee. J. Magn. Reson. Imaging 2008;28:453–461. © 2008 Wiley‐Liss, Inc.
Free‐breathing 3D steady‐state free precession coronary magnetic resonance angiography: Comparison of diaphragm and cardiac fat navigators
Authors: Nguyen Thanh D. , Spincemaille Pascal , Cham Matthew D. , Weinsaft Jonathan W. , Prince Martin R. , Wang Yi 
Published: July 2008

AbstractPurposeTo compare the performance of the conventional diaphragm navigator (DNAV) and the recently developed cardiac fat navigator (FatNAV) in suppressing respiration‐induced cardiac motion in free‐breathing 3D balanced steady‐state free precession coronary MRA (SSFP CMRA).Materials and MethodsIn 16 healthy volunteers the right coronary artery (RCA) was imaged at 1.5T using a navigator‐gated 3D SSFP CMRA sequence. DNAV and FatNAV gating were performed in random order. Image quality difference was scored by three experienced readers blinded to the gating technique. Blood signal‐to‐noise ratio (SNR), blood‐to‐myocardium contrast‐to‐noise ratio (CNR), and navigator efficiency were calculated.ResultsDiagnostically interpretable CMRA was obtained successfully in all 16 subjects with FatNAV gating (0% failure rate) and only 14 subjects with DNAV gating (12% failure rate). Compared to DNAV gating, FatNAV gating provided similar SNR and CNR, better image quality (P < 0.01), and 28% improvement in navigator efficiency (P = 0.002).ConclusionFatNAV gating provides more effective motion suppression and better image quality than DNAV gating for free‐breathing 3D SSFP CMRA of the RCA in healthy subjects. J. Magn. Reson. Imaging 2008;28:509–514. © 2008 Wiley‐Liss, Inc.
Monitoring infection and inflammation in murine models of cystic fibrosis with magnetic resonance imaging
Authors: Sheth Vipul R. , van Heeckeren R. Christiaan , Wilson Alma G. , van Heeckeren Anna M. , Pagel Mark D. 
Published: July 2008

AbstractPurposeTo evaluate magnetic resonance imaging (MRI) in assessing lung inflammation longitudinally in genetic mouse models of cystic fibrosis (CF). MRI is used to view soft tissues noninvasively, but the lung is challenging to image.Materials and MethodsCftr+/+ (wildtype) and Cftr−/− (CF) mice were inoculated with agarose beads laden with Pseudomonas aeruginosa. Longitudinal MR lung images were acquired with cardiac gating. The effects of echo time and respiration gating were evaluated to improve the detection of lung inflammation.ResultsCardiac gating and signal averaging sufficiently suppressed motion artifacts without requiring respiration gating. MRI detected moderate to severe inflammation in infected mice, which was confirmed by histology results.ConclusionIn vivo longitudinal MRI methods can assess lung inflammation in P. aeruginosa‐infected mice, which obviates serial sacrifice. MRI was able to detect inflammation in the absence of other physiological symptoms. J. Magn. Reson. Imaging 2008;28:527–532. © 2008 Wiley‐Liss, Inc.
Single breath‐hold multiarterial dynamic MRI of the liver at 3T using a 3D fat‐suppressed keyhole technique
Authors: Hong Hye‐Suk , Kim Hua Sun , Kim Myeong‐Jin , De Becker Jan , Mitchell Donald G. , Kanematsu Masayuki 
Published: July 2008

AbstractPurposeTo evaluate the feasibility of single breath‐hold, multiarterial MRI of the liver using the THRIVE‐CENTRA‐keyhole technique.Materials and MethodsTwenty‐eight patients with 63 focal hepatic lesions underwent liver MR examinations that included the three‐dimensional THRIVE‐CENTRA‐keyhole sequence. Three or six phases were obtained for arterial phase scanning during a single breath‐hold. Central k‐space data were collected for each phase but the remaining peripheral k‐space data were collected only once. The enhancement pattern of each hepatic lesion was analyzed according to the specific diagnosis.ResultsHepatocellular carcinomas (n = 24) enhancement patterns included: rim enhancing (n = 9), homogeneous (n = 7), nodule‐in‐nodule (n = 5), or heterogeneous (n = 3). A late peritumoral rim was observed in four (17%) of the hepatocellular carcinomas. Most metastases (17 of 18; 94%) demonstrated peripheral rim enhancement. The progressive centripetal enhancement of hemangiomas (n = 6) was clearly depicted. Focal nodular hyperplasia (n = 4) showed early homogeneous enhancement and one lesion demonstrated a central scar.ConclusionThe THRIVE‐CENTRA‐keyhole technique can be used to acquire single breath‐hold, multiarterial images depicting improved enhancement characteristics of focal hepatic lesions. This technique will allow accurate timing of arterial scanning with 3D acquisition and high temporal resolution. J. Magn. Reson. Imaging 2008;28:396–402. © 2008 Wiley‐Liss, Inc.
Comparison of different contrast agents and doses for quantitative MR myocardial perfusion imaging
Authors: Köstler Herbert , Ritter Christian , Lipp Michael , Beer Meinrad , Hahn Dietbert , Sandstede Jörn 
Published: July 2008

AbstractPurposeTo investigate three different contrast agents at different injection volumes for repetitive quantitative multislice myocardial perfusion imaging using the prebolus technique.Materials and MethodsTwo consecutive prebolus perfusion measurements were performed on a 1.5T scanner using identical injection volumes for the first and second examination to test the reproducibility for possible rest and stress examination in normal volunteers. Either 1–8 mL, 1–12 mL Gd‐DTPA, 1–4 mL, 1–6 mL, 1–9 mL Gd‐BOPTA, or 1–4 mL, 1–6 mL gadobutrol were applied.ResultsIn cases where injection volumes were sufficiently small, there was no indication of significant differences in quantitative perfusion values with respect to the different contrast agents. Increasing the bolus volume improved the contrast‐to‐noise ratio (CNR) but led to saturation effects and underestimation of the true perfusion. The highest CNR was measured for gadobutrol (6 mL, p < 0.0005 compared to 8 mL Gd‐DTPA). The smallest difference of perfusion values between the first and the second prebolus examination was found for Gd‐BOPTA (p ≤ 0.006 compared Gd‐DTPA).ConclusionPrebolus examinations for quantitative myocardial perfusion imaging are possible with all three contrast agents for sufficient small injection volumes. Gd‐BOPTA was found to be advantageous for a combined quantitative rest and stress examination. J. Magn. Reson. Imaging 2008;28:382–389. © 2008 Wiley‐Liss, Inc.
Heschl gyrus and its included primary auditory cortex: Structural MRI studies in healthy and diseased subjects
Authors: Abdul‐Kareem Ihssan A. , Sluming Vanessa 
Published: July 2008

AbstractDespite the fact that the Heschl gyrus (HG) is a crucial brain structure as it contains the primary auditory cortex (PAC), relatively few structural MRI studies have concentrated upon it. We propose that this may be attributed in part to the considerable variability of this structure and, most importantly, to the lack of unified criteria for defining the extent of the PAC along the MRI‐determined landmarks of the HG, which ultimately affects the reliability and reproducibility of these studies. This review highlights three aspects: first, the standard and variant anatomy of the HG and PAC with particular focus on MRI definition of these regions; second, the importance of studying the HG and PAC in health and disease using structural MRI; and, third, the problem of MRI localization of the PAC. The scientific community should be aware that the HG and its included PAC are not synonyms. Additionally, owing to the great complexity and variability of these regions, future MRI studies should be cautious when using single brain‐based atlas or maps generated by simply averaging across individuals to localize these regions. Instead, and while waiting for future in vivo microstructural localization of the PAC, the use of probabilistic and functional maps is advantageous but not without shortcomings. J. Magn. Reson. Imaging 2008;28:287–299. © 2008 Wiley‐Liss, Inc.
Quantification of left ventricular internal flow from cardiac magnetic resonance images in patients with dyssynchronous heart failure
Authors: Fornwalt Brandon K. , Gonzales Patrick C. , Delfino Jana G. , Eisner Robert , León Angel R. , Oshinski John N. 
Published: July 2008

AbstractPurposeTo develop a method for quantifying left ventricular (LV) internal flow as a measure of dyssynchrony using standard cine cardiac magnetic resonance (CMR) images.Materials and MethodsCMR images were obtained from 10 healthy controls and 10 patients with dyssynchronous heart failure (class III/IV, LV ejection fraction <35%, pattern seen in an electrocardiogram QRS duration > 150 msec). The LV volume was reconstructed and divided into 16 regions. Internal flow was defined as the sum of the regional volume changes minus the global volume change during each time step in the cardiac cycle. Internal flow fraction (IFF) was defined as the total internal flow as a percentage of stroke volume during systole (IFFsystole), diastole (IFFdiastole), or the whole cycle (IFFwhole).ResultsIFFwhole was significantly increased in the patients (9.9 ± 5.0% vs. 1.5 ± 0.5% in the controls, P < 0.001). An IFFwhole threshold of 4% discriminated between patients and controls with 90% sensitivity and 100% specificity. IFFdiastole (2.3 ± 0.8%) was greater than IFFsystole (0.8 ± 0.5%) in the normal controls (P < 0.001) while the patients had similar IFFdiastole (7.8 ± 4.2%) and IFFsystole (12.0 ± 7.8%).ConclusionLeft ventricular internal flow fraction can be quantified from standard CMR images. In this preliminary study, Left ventricular internal flow fraction discriminated patients with dyssynchronous heart failure from normal controls with 95% accuracy. J. Magn. Reson. Imaging 2008;28:375–381. © 2008 Wiley‐Liss, Inc.
Quantifying cerebral changes in adolescence with MRI and deformation based morphometry
Authors: Riddle William R. , DonLevy Susan C. , Wushensky Curtis A. , Dawant Benoit M. , Fitzpatrick J. Michael , Price Ronald R. 
Published: July 2008

AbstractPurposeTo identify and quantify structural changes in the maturing brain between childhood and adolescence.Materials and MethodsTwo three‐dimensional T1‐weighted MR volumes of the brain were acquired from eight subjects, 6 to 7 years apart. The subjects were 9 to 12 years old on the first scan and 15 to 19 years old on the second scan. The MR scans were converted to one millimeter isotropic volumes, globally aligned with a rigid transform, inhomogeneity corrected, and nonrigid deformation fields between the aligned volumes were calculated. Masks for brain regions were automatically warped with the deformation fields and volumes of brain regions calculated. Color overlays based on the nonrigid deformation fields were generated to identify local volume changes.ResultsGray matter decreased as much as 60% and white matter increased as much as 250%. The biggest gray matter changes were in the head of the caudates, areas of the putamens, and areas of the thalamus. Some of the biggest white matter changes were in the forceps minor, forceps major, and internal capsule.ConclusionDeformation based morphometry with serial scans provides a method to study regional structural changes with brain growth and maturation. J. Magn. Reson. Imaging 2008;28:320–326. © 2008 Wiley‐Liss, Inc.
Automatic image‐driven segmentation of the ventricles in cardiac cine MRI
Authors: Cocosco Chris A. , Niessen Wiro J. , Netsch Thomas , Vonken Evert‐jan P.A. , Lund Gunnar , Stork Alexander , Viergever Max A. 
Published: July 2008

AbstractPurposeTo propose and to evaluate a novel method for the automatic segmentation of the heart's two ventricles from dynamic (“cine”) short‐axis “steady state free precession” (SSFP) MR images. This segmentation task is of significant clinical importance. Previously published automated methods have various disadvantages for routine clinical use.Materials and MethodsThe proposed method is primarily image‐driven: it exploits the spatiotemporal information provided by modern 3D+time SSFP cardiac MRI, and makes only few and plausible assumptions about the image acquisition and about the imaged heart. Specifically, the method does not require previously trained statistical shape models or gray‐level appearance models, as often used by other methods.ResultsThe performance of the segmentation method was demonstrated through a qualitative visual validation on 32 clinical exams: no gross failures for the left‐ventricle (right‐ventricle) on 31 (29) of the exams were found. A validation of resulting quantitative cardiac functional parameters showed good agreement with a manual quantification of 19 clinical exams.ConclusionThe proposed method is feasible, fast, and robust against anatomical variability and image contrast variations. J. Magn. Reson. Imaging 2008;28:366–374. © 2008 Wiley‐Liss, Inc.