bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vertebral development of modern salamanders provides insights into a unique event of their evolutionary history
Authors: Boisvert Catherine Anne 
Published: November 2008

AbstractThe origin of salamanders and their interrelationships to the two other modern amphibian orders (frogs and caecilians) are problematic owing to an 80–100 million year gap in the fossil record between the Carboniferous to the Lower Jurassic. This is compounded by a scarcity of adult skeletal characters linking the early representatives of the modern orders to their stem‐group in the Paleozoic. The use of ontogenetic characters can be of great use in the resolution of these questions. Growth series of all ten modern salamander families (a 120 cleared and stained larvae) were examined for pattern and timing of vertebral elements chondrification and ossification. The primitive pattern is that of the neural arches developing before the centra, while the reverse represents the derived condition. Both the primitive and derived conditions are observed within the family Hynobiidae, whereas only the derived condition is observed in all other salamanders. This provides support to the claims that Hynobiidae is both the most basal of modern families and potentially polyphyletic (with Ranodon and Hybobius forming the most basal clade and Salamandrella being a part of the most derived clade). This provides insight into a unique event in salamander evolutionary history and suggests that the developmental pattern switch occurred between the Triassic and the mid‐Jurassic before the last major radiation. J. Exp. Zool. (Mol. Dev. Evol.) 312B:1–29, 2009. © 2008 Wiley‐Liss, Inc.
Accelerated bilateral dynamic contrast‐enhanced 3D spiral breast MRI using TSENSE
Authors: Han Misung , Daniel Bruce L. , Hargreaves Brian A. 
Published: November 2008

AbstractPurposeTo assess the ability of adaptive sensitivity encoding incorporating temporal filtering (TSENSE) to accelerate bilateral dynamic contrast‐enhanced (DCE) 3D breast MRI.Materials and MethodsBilateral DCE breast magnetic resonance imaging (MRI) exams were performed using a dual‐band water‐only excitation and a “stack‐of‐spirals” imaging trajectory. TSENSE was applied in the slab direction with an acceleration factor of 2. Four different techniques for sensitivity map calculation were compared by analyzing resultant contrast uptake curves qualitatively and quantitatively for 10 patient datasets. In addition, image quality and temporal resolution were compared between unaccelerated and TSENSE images.ResultsTSENSE can increase temporal resolution by a factor of 2 in DCE imaging, providing better depiction of contrast uptake curves and good image quality. Of the different methods tested, calculation of static sensitivity maps by averaging late postcontrast frames yields the lowest aliasing artifact level based on ROI analysis.ConclusionTSENSE acceleration combined with 3D spiral imaging is very time‐efficient, providing 11‐second temporal resolution and 1.1 × 1.1 × 3 mm3 spatial resolution over a 20 × 20 × 10 cm3 field of view for each breast. J. Magn. Reson. Imaging 2008;28:1425–1434. © 2008 Wiley‐Liss, Inc.
Fibrocystic change of the breast presenting as a focal lesion mimicking breast cancer in MR imaging
Authors: Chen Jeon‐Hor , Nalcioglu Orhan , Su Min‐Ying 
Published: November 2008

AbstractFocal fibrocystic change (FCC) of the breast is a rare form of FCC. Imaging presentations of focal FCC are not well known. This study aimed to analyze its MR imaging features. Eleven patients of pathology‐proven focal FCC were retrospectively studied. Of the 11 patients, seven were mass (≥5 mm), two showed multiple foci, and two were focus (<5 mm). The lesion size ranged from 4–12 mm (mean 6.7 mm). Morphologically, three patients were suspected as malignancy. Using kinetic enhancement curve, 8 of 13 lesions were suspected to be malignant. Overall, nine patients (82%) were suspected for malignancy using either criterion. Using mammography, 6 of the 11 patients (55%) were diagnosed as malignancy. Breast sonography suspected malignancy in seven patients (7/10, 70%). No statistically significant difference was found in the three diagnostic methods. In pathology, all 11 patients showed the typical pathological features of fibrocystic change, with mixed components of stromal fibrosis, cyst formation, apocrine metaplasia, adenosis, and/or focal sclerosing adenosis. In conclusion, MR imaging features of focal FCC usually present as a mass or focus lesion with rapid enhancement and washout kinetics that mimic a malignant breast lesion and lead to unnecessary operation, especially in patients with contralateral malignant breast cancer. J. Magn. Reson. Imaging 2008;28:1499–1505. © 2008 Wiley‐Liss, Inc.
Safety of gadoversetamide in patients with acute and chronic myocardial infarction
Authors: Huber S. , Muthupillai R. , Cheong B. , Wible J.H. , Shah D. , Woodard P. , Grothues F. , Mahrholdt H. , Rochitte C.E. , Masoli O. , Kim R.J. , Schwaiger C.M. , Fuisz A. , Kramer C. , van Rossum A.C. , Biederman R. , Lombardi M. , Martin E. , Kevorkian R. , Flamm S.D. 
Published: November 2008

AbstractPurposeTo assess the safety data from two large, multicenter, phase 2 trials on the use of gadoversetamide (OptiMARK, Tyco Healthcare/Mallinckrodt, St. Louis, MO) as a contrast agent in delayed hyperenhancement magnetic resonance imaging (DE‐MRI) in patients with acute and chronic myocardial infarction (MI).Materials and MethodsThe study population from both trials comprised 577 patients who were randomly assigned to one of four dose groups (0.05, 0.1, 0.2, or 0.3 mmol/kg) before undergoing DE‐MRI. Safety evaluations included physical and electrocardiographic (ECG) examinations. Vital signs, laboratory values, adverse events (AE), and serious adverse events (SAE) were monitored before and after contrast administration.ResultsOf the 577 patients who received gadoversetamide, 124 (21.5%) reported a total of 164 AEs; most were mild (139 AEs; 84.8%) or moderate (25 AEs; 15.2%). ECG‐related changes were the most frequent AE. Site investigators judged only eight AEs as likely related to gadoversetamide and only two of the eight as clinically relevant. Further evaluation suggested neither AE was related to gadoversetamide. Two SAEs were reported, but none was judged related to gadoversetamide by the site investigators.ConclusionGadoversetamide is safe for use in patients with acute or chronic MI up to a dose of 0.3 mmol/kg. J. Magn. Reson. Imaging 2008;28:1368–1378. © 2008 Wiley‐Liss, Inc.
Regional right ventricular function and timing of contraction in healthy volunteers evaluated by strain‐encoded MRI
Authors: Hamdan Ashraf , Thouet Thomas , Sebastian Kelle , Paetsch Ingo , Gebker Rolf , Wellnhofer Ernst , Schnackenburg Bernhard , Fahmy Ahmed S. , Osman Nael F. , Fleck Eckart 
Published: November 2008

AbstractPurposeTo prospectively determine the feasibility and accuracy of strain‐encoded (SENC) magnetic resonance imaging (MRI) for the characterization of the right ventricular free wall (RVFW) strain and timing of contraction at 3.0 Tesla (3T) MRI.Materials and MethodsIn 12 healthy volunteers the RVFW was divided into three segments (anterior, lateral, and inferior) in each of three short‐axis (SA) slices (apical, mid, and basal) and into three segments (apical, mid, and basal) in a four‐chamber view. The study was repeated on a different day and interobserver and interstudy agreements were evaluated.ResultsMaximal systolic longitudinal strain values were highest at the apex and base, with a pronounced decrease in the medial segments (apex: –19.1% ± 1.4; mid: –17.4% ± 2; base: –19.4% ± 2.4, P < 0.001), and maximal systolic circumferential strain showed the highest values at the apex (apex: –18.1% ± 1.7; mid: –17.6% ± 1.2; base: –16.6% ± 0.9, P < 0.001). Peak systolic longitudinal and circumferential shortening occurred earliest at the apex compared to the mid‐ventricle and base. Excellent interobserver and interstudy correlation and agreement were observed.ConclusionThe use of SENC MRI for the assessment of normal RV contraction pattern is feasible and accurate in 3T MRI. J. Magn. Reson. Imaging 2008;28:1379–1385. © 2008 Wiley‐Liss, Inc.
Measurement of common carotid artery lumen dynamics during the cardiac cycle using magnetic resonance TrueFISP cine imaging
Authors: Chow Tracy Y. , Cheung Jerry S. , Wu Yin , Guo Hua , Chan Kevin C. , Hui Edward S. , Wu Ed X. 
Published: November 2008

AbstractPurposeTo demonstrate magnetic resonance (MR) measurements of vascular lumen dynamics in common carotid arteries by using true fast imaging with steady‐state precession (TrueFISP) cine imaging with an aim to provide additional physiologic information on the vessels.Materials and MethodsThe left and right common carotid arteries were studied in normal young men (N = 6; age = 21–24 years; body weight = 130–175 lbs) using electrocardiogram (ECG)‐triggered TrueFISP cine imaging at 20 frames per cardiac cycle. Lumen area waveforms were characterized with specific time and amplitude ratios. Distension values were quantified.ResultsDistension values were measured at 25.92 ± 2.58% and 27.58 ± 4.44% for the left and right common carotid arteries, respectively. These findings are consistent with those previously documented using ultrasound imaging in a similar age group. Consistent lumen area waveform characteristics were found among the subjects studied.ConclusionThese findings demonstrate for the first time that the use of TrueFISP cine imaging is a robust, rapid technique for quantifying carotid lumen area dynamics and distension, which may be valuable in characterizing and diagnosing cardiovascular diseases. J. Magn. Reson. Imaging 2008;28:1527–1532. © 2008 Wiley‐Liss, Inc.
Vertebral blood perfusion reduction associated with vertebral bone mineral density reduction: A dynamic contrast‐enhanced MRI study in a rat orchiectomy model
Authors: Wang Yi‐Xiang J. , Zhang Ya‐Feng , Griffith James F. , Zhou Hua , Yeung David K.W. , Kwok Timothy C. , Qin Ling , Ahuja Anil T. 
Published: November 2008

AbstractPurposeTo investigate the relationship between vertebral blood perfusion and vertebral bone mineral density (BMD) in a rat orchiectomy (ORX) model.Materials and MethodsNine 6‐month‐old male Wistar‐Kyoto rats were used. Computed tomography (CT) bone densitometry and dynamic MRI were performed at baseline and four weeks post‐ORX. MRI was performed on a 1.5T clinical MR scanner with a small surface coil placed under the rat lumbar spine region. A sagittal midsection of the lumbar spine was prescribed. Dynamic MRI was performed after a bolus injection of gadolinium‐tetraazacyclododecane tetraacetic acid (Gd‐DOTA) (0.3 mmol/kg) administered through a tail vein cannula. At a temporal resolution of 0.6 seconds, 800 images were acquired. Regions‐of‐interest were drawn comprising the medullary component of lumbar vertebrae L3–L6. Maximum enhancement was analyzed.ResultsSatisfactory CT and MRI data for analysis was obtained in all animals. Vertebral BMD decreased by 16.6% at four weeks post‐ORX (1.134 ± 0.035 vs. 0.946 ± 0.027 g/cm3, P = 0.008). MRI maximum enhancement decreased by 17% at four weeks post‐ORX (151.5 ± 12.0% vs. 125.8 ± 9.9%, P = 0.015).ConclusionVertebral blood perfusion reduction is associated with vertebral BMD reduction in a male rat osteoporosis model. Perfusion MRI provides a new investigative technique for osteoporosis experimental research. J. Magn. Reson. Imaging 2008;28:1515–1518. © 2008 Wiley‐Liss, Inc.
Venous congestion associated with developmental venous anomaly: Findings on susceptibility weighted imaging
Authors: Amemiya Shiori , Aoki Shigeki , Takao Hidemasa 
Published: November 2008

AbstractA case of venous congestion associated with developmental venous anomaly (DVA) in a 5‐year‐old girl who presented with acute deterioration of consciousness is reported. Susceptibility‐weighted imaging revealed abnormal structures connected to the central collector of a DVA, which were not shown on other sequences. These structures were considered to be presumably thrombosed medullary veins. J. Magn. Reson. Imaging 2008;28:1506–1509. © 2008 Wiley‐Liss, Inc.
MR angiography of the cerebral perforating arteries with magnetization prepared anatomical reference at 7T: Comparison with time‐of‐flight
Authors: Zwanenburg Jaco J.M. , Hendrikse Jeroen , Takahara Taro , Visser Fredy , Luijten Peter R. 
Published: November 2008

AbstractPurposeTo develop a magnetic resonance imaging (MRI) protocol that visualizes both the perforating arteries and the related anatomy in a single acquisition at 7T.Material and MethodsT1‐weighted magnetization prepared imaging (MPRAGE) was empirically modified for use as angiography method at 7T. The resulting sequence depicts the vasculature simultaneously with the surrounding anatomical structures, and is referred to as “magnetization prepared anatomical reference MRA” (MPARE‐MRA). The method was compared to time‐of‐flight (TOF) MRA in seven healthy subjects. The conspicuity of the perforating arteries and the contrast between gray and white matter were evaluated both quantitatively by contrast‐to‐noise (CNR) measurements, and qualitatively by two radiologists who scored the images.ResultsThe contrast‐to‐noise ratio (CNR) between blood and background was 28 ± 9 for MPARE‐MRA and 35 ± 16 for TOF‐MRA, indicating good conspicuity of the vessels. CNR values were: internal capsule (IC) vs. caudate head (CH): 4.2 ± 0.7; IC vs. putamen: 3.5 ± 0.6; white matter vs. gray matter: 9.7 ± 2.5.ConclusionThe benefits of ultra‐high‐field MRI can transform MPRAGE into a new angiography method to image small vessels and associated parenchyma at the same time. This technique can be used to study the correlation between tissue damage and vascular pathology. J. Magn. Reson. Imaging 2008;28:1519–1526. © 2008 Wiley‐Liss, Inc.
1H HR‐MAS spectroscopy for quantitative measurement of choline concentration in amniotic fluid as a marker of fetal lung maturity: Inter‐ and intraobserver reproducibility study
Authors: Joe Bonnie N. , Vahidi Kiarash , Zektzer Andrew , Chen Mei‐Hsiu , Clifton Matthew S. , Butler Thomas , Keshari Kayvan , Kurhanewicz John , Coakley Fergus , Swanson Mark G. 
Published: November 2008

AbstractPurposeTo determine the intra‐ and interobserver reproducibility of human amniotic fluid metabolite concentration measurements (including potential markers of fetal lung maturity) detectable by MR spectroscopy.Materials and Methods1H high‐resolution magic angle spinning (HR‐MAS) spectroscopy was performed at 11.7T on 23 third‐trimester amniotic fluid samples. Samples were analyzed quantitatively using 3‐(trimethylsilyl)propionic‐2,2,3,3‐d4 acid (TSP) as a reference. Four observers independently quantified eight metabolite regions (TSP, lactate doublet and quartet, alanine, citrate, creatinine, choline, and glucose) twice from anonymized, randomized spectra using a semiautomated software program.ResultsExcellent inter‐ and intraobserver reproducibility was found for all metabolites. Intraclass correlation as a measure of interobserver agreement for the four readers ranged from 0.654 to 0.995. A high correlation of 0.973 was seen for choline in particular, a major component of surfactant. Pearson correlation as a measure of intraobserver reproducibility ranged from 0.478 to 0.999.ConclusionQuantification of choline and other metabolite concentrations in amniotic fluid by high‐resolution MR spectroscopy can be performed with high inter‐ and intraobserver reproducibility. Demonstration of reproducible metabolite concentration measurements is a critical first step in the search for biomarkers of fetal lung maturity. J. Magn. Reson. Imaging 2008;28:1540–1545. © 2008 Wiley‐Liss, Inc.
Evaluating the severity of nonalcoholic steatohepatitis with superparamagnetic iron oxide‐enhanced magnetic resonance imaging
Authors: Tomita Kengo , Tanimoto Akihiro , Irie Rie , Kikuchi Masahiro , Yokoyama Hirokazu , Teratani Toshiaki , Suzuki Takahiro , Taguchi Takashi , Noguchi Masaaki , Ohkura Tamiko , Hibi Toshifumi 
Published: November 2008

AbstractPurposeTo evaluate the utility of noninvasive assessment of human nonalcoholic fatty liver disease (NAFLD) patients using superparamagnetic iron oxide (SPIO)‐enhanced MRI.Materials and MethodsNineteen NAFLD patients underwent SPIO‐enhanced MRI. The values of τ, a time constant for an exponential approximation, were calculated using gradient‐echo echo‐planar imaging, and the values of %T2, a marker of the T2 relaxation effect of SPIO, were calculated using T2‐weighted fast spin‐echo images. Correlations between these values and the histological NAFLD activity scores were evaluated. The study protocol was approved by our Institutional Review Board and all patients gave informed consent.ResultsThere was a statistically significant relationship between the NAFLD activity scores and the τ values (r = 0.66, P = 0.002). The %T2 values were also significantly correlated with the NAFLD activity score (r = −0.58, P = 0.009). A cutoff τ value of 42.8 predicted “definitive NASH” (NAFLD activity score ≥5) with a specificity of 66.7% and a sensitivity of 99.9%, whereas a cutoff %T2 value of 32.5 predicted “definitive NASH” with a specificity of 72.7% and a sensitivity of 87.5%.ConclusionNoninvasive SPIO‐enhanced MRI may be helpful for identifying NASH patients among patients suspected of having NAFLD. J. Magn. Reson. Imaging 2008;28:1444–1450. © 2008 Wiley‐Liss, Inc.
MR imaging findings of early bile duct cancer
Authors: Lee Dong Ho , Lee Jeong Min , Kim Kyung Won , Park Hee Sun , Kim Se Hyung , Lee Jae Young , Han Joon Koo , Choi Byung Ihn 
Published: November 2008

AbstractPurposeTo retrospectively evaluate the MR imaging features of early bile duct cancer and to correlate them with the clinicopathologic findings.Materials and MethodsThis retrospective study was approved by our institutional review board, and informed consent was waived. Seventeen patients with surgically proven early bile duct cancer who had undergone preoperative MR cholangiopancreatography with gadolinium‐enhanced MR imaging, were included in this study. Two, experienced radiologists evaluated the MR images in consensus regarding the following findings: tumor number and morphology; signal intensity of the tumor; sharpness of the outer border of the bile duct wall; enhancement pattern of the tumor; and the presence of enlarged peribiliary lymph nodes. Another radiologist measured the SNR of the tumor and bile duct wall on gadolinium‐enhanced MRI during the dynamic phases to evaluate the tumor enhancement degree.ResultsIn all patients, MR imaging demonstrated single or multiple intraluminal bile duct masses showing a sharply defined outer margin. The most common enhancement pattern of the biliary lesions showed heterogeneous amorphous enhancement or heterogeneous enhancement with central, dot‐like structures or vascular structures (76.5%, 13/17 patients). The difference of SNR between bile duct and tumor was greatest in the equilibrium phase (P < 0.05).ConclusionMRCP combined with dynamic contrast‐enhanced MRI can be useful for detecting early bile duct cancers. Common MR findings of early bile duct cancer include one or more inhomogeneously enhancing intraductal masses with clear outer margins and preservation of the bile duct wall. J. Magn. Reson. Imaging 2008;28:1466–1475. © 2008 Wiley‐Liss, Inc.
Measurement of T1, T2, and magnetization transfer properties during embryonic development at 7 Tesla using the chicken model
Authors: Boss Andreas , Oppitz Matthias , Wehrl Hans F. , Rossi Cristina , Feuerstein Markus , Claussen Claus D. , Drews Ulrich , Pichler Bernd J. , Schick Fritz 
Published: November 2008

AbstractPurposeTo evaluate whether techniques of high field magnetic resonance imaging may be used to characterize embryonic tissue during proliferation and differentiation.Materials and MethodsThirteen chicken embryos with incubation times between 5 days and 16 days have been measured in a small animal magnetic resonance imager (ClinScan, Bruker) at 7 Tesla using the built‐in resonator. T1, T2‐, and magnetization transfer imaging was performed using fast spin‐echo with inversion recovery, half acquisition single shot turbo spin‐echo, and spoiled gradient‐echo sequences with and without off‐resonance pulse, respectively. T1, T2, and magnetization transfer ratio (MTR) maps were calculated on a pixel‐by‐pixel basis.ResultsT1‐, T2‐, and MTR maps showed good image quality allowing for delineation of embryonic organs. During embryonic development, a decrease of T1 and T2 relaxation times was found, whereas, embryonic tissue typically showed an increase of magnetization transfer, for example, liver properties at day 5: T1 = 2431 ± 163 ms, T2 = 122 ± 12 ms, MTR = 9.2 ± 4.2%; liver properties at day 16: T1 = 1763 ± 89 ms, T2 = 71 ± 4 ms, MTR = 16.9 ± 2.2%.ConclusionEmbryonic tissues show changing relaxation and magnetization transfer properties during development, therefore, high field MRI seems suitable for characterization of tissue replacement derived from embryonic stem cells. J. Magn. Reson. Imaging 2008;28:1510–1514. © 2008 Wiley‐Liss, Inc.
Simulation study of susceptibility gradients leading to focal myocardial signal loss
Authors: Anderson Douglas J. , Dendy Jeffrey M. , Paschal Cynthia B. 
Published: November 2008

AbstractPurposeTo assess the cause of a “bite”‐shaped signal void artifact often seen in 1.5 Tesla (T) and 3T gradient echo MR images in myocardium along the infero‐apical border of the heart, MRI simulation was used to conduct experiments impossible in reality. Two previous studies attempting to explain the origin of this artifact came to different conclusions. One suggested deoxygenated blood in the posterior vein of the left ventricle (PVLV) leads to a susceptibility gradient that causes the artifact. The other suggested the difference in susceptibility between lung tissue and myocardium was responsible. This study assessed the relative effect of each possible cause.Materials and MethodsAnthropometric phantoms were developed for use with a previously reported MRI simulator. The images were simulated at 3T with gradient echo scans using TE = 4 ms, TR = 25 ms, and θ = 25°.ResultsThe simulations indicate that both susceptibility differences can lead to signal losses in the area of the artifact with contributions from the PVLV being more localized while lung tissue effects are stronger but more spatially distributed.ConclusionThe data support the conclusion that both differences together, rather than one or the other, are responsible for the artifact. J. Magn. Reson. Imaging 2008;28:1402–1408. © 2008 Wiley‐Liss, Inc.