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Anatomic Features (anatomic + feature)
Selected AbstractsComputed Tomographic, Magnetic Resonance Imaging, and Cross-Sectional Anatomic Features of the Manus in a Normal American Black Bear (Ursus americanus)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2010C. P. Ober With 11 figures and 1 table Summary The purpose of this study was to provide a detailed description of cross-sectional anatomic structures of the manus of a black bear cadaver and correlate anatomic findings with corresponding features in computed tomographic (CT) and magnetic resonance (MR) images. CT, MR imaging, and transverse sectioning were performed on the thoracic limb of a cadaver female black bear which had no evidence of lameness or thoracic limb abnormality prior to death. Features in CT and MR images corresponding to clinically important anatomic structures in anatomic sections were identified. Most of the structures identified in transverse anatomic sections were also identified using CT and MR imaging. Bones, muscles and tendons were generally easily identified with both imaging modalities, although divisions between adjacent muscles were rarely visible with CT and only visible sometimes with MR imaging. Vascular structures could not be identified with either imaging modality. [source] Basic principles of MRI and morphometry studies of human brain developmentDEVELOPMENTAL SCIENCE, Issue 3 2002David N. Kennedy Magnetic resonance imaging has undergone dramatic development in the past years. This has been paralleled by developments in the tools for extracting quantitative information from these images in support of capturing the anatomic features of brain development in living humans. This has revolutionized our expectations for current and future diagnostic and investigative work with the developing brain. This paper will cover the classes of information that are readily available in the MR image, the mechanisms for extracting quantitative results, and a sample of the application of these types of methods to developmental issues. These applications highlight tissue- and anatomic-based contrasts in the nature and rate of developmental maturation within the brain. This will be followed by a discussion of the emergent themes of developmental science as elucidated by these classes of observation. [source] Atrial Morphology in Hearts with Congenitally Corrected Transposition of the Great Arteries: Implications for the InterventionistJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2002RAJNISH JUNEJA M.D. Atrial Morphology in Congenitally Corrected Transposition.Introduction: In view of the possible need for septal puncture to ablate left-sided lesions and the occasional difficulty in coronary sinus (CS) cannulation, we investigated relevant anatomic features in the right atrium of hearts with congenitally corrected transposition of the great arteries (ccTGA). Methods and Results: Nine hearts with ccTGA and an intact atrial septum and eight weight-matched normal hearts were examined by studying the "septal" aspect of the right atrium with reference to the oval fossa (OF). The anterior margin was arbitrarily measured as the shortest distance from the OF to the superior mitral/tricuspid annulus. The posterior margin was measured from the OF to the posterior-most edge of the right atrial "septal" surface. The total "septal" surface width was measured at the middle of the OF. The stretched OF dimensions and CS isthmus length were noted. Mann-Whitney test was used to compare absolute and indexed dimensions, i.e.. normalized to total width. The posterior margin in hearts with ccTGA was shorter than in controls (6.3 ± 2.4 mm vs 11 ± 1.9 mm, P < 0.001; normalized margin P = 0.09). The CS isthmus also was significantly shorter (5.3 ± 2.7 mm vs 11.4 ± 2.2 mm, P < 0.001). In two hearts with ccTGA, the CS opening into the right atrium was on the same side of the eustachian valve as the inferior caval vein. Conclusion: The shorter posterior "septal" margin in hearts with ccTGA may increase the risk of exiting the heart while performing septal puncture when pointing the needle posteriorly. The shorter CS isthmus and the abnormal location of the CS opening in some of these hearts are important when contemplating radiofrequency ablation in this area. [source] Necropsy by magnetic resonance in a case of conjoined thoracopagus twinsJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2001A.C. Manzano MD Abstract A case of thoracopagus conjoined stillborn twins studied with magnetic resonance imaging (MRI) is presented. Due to the parents' denial of authorization for an autopsy of the fetuses, the MRI study was performed as an alternative to necropsy. High-resolution images of the fetuses demonstrated relevant anatomic features, providing noninvasive pathological insight with preservation of the fetal specimen. J. Magn. Reson. Imaging 2001;13:976,981. © 2001 Wiley-Liss, Inc. [source] Measurement of Angle and Length of the Eustachian Tube on Computed Tomography Using the Multiplanar Reconstruction TechniqueTHE LARYNGOSCOPE, Issue 7 2007Kenji Takasaki MD Abstract Objective: To compare the anatomic features of the eustachian tube (ET) between children with and without otitis media with effusion (OME) and with adults. Methods: The angle and length of the ET in children with OME (54 ears, OME children) and without OME (50 ears, normal children), as well as those of normal adults (90 ears), were measured on computed tomography using the multiplanar reconstruction technique. Results: The angles of ET in the OME children group, the normal children group, and the normal adult group were 20.4 ± 3.5° and 21.2 ± 4.8°, 19.9 ± 3.4° and 20.0 ± 3.6°, and 27.3 ± 2.7° and 27.3 ± 2.8° on the right and the left sides, respectively. There was no significant difference between the right and the left side in any group (P = .541, P = .952, P = .978). The lengths of ET in the OME children group, the normal children group, and the normal adult group were 37.2 ± 3.0 mm (mean ± SD) and 37.6 ± 3.2 mm, 37.5 ± 3.3 mm and 38.0 ± 3.2 mm, and 42.5 ± 2.8 mm and 42.9 ± 2.9 mm on the right and the left sides, respectively. There was no significant difference between the right and left sides in any group (P = .670, P = .597, and P = .545). Both the angles and lengths were significantly greater in the normal adult group than in either the OME children group or the normal children group (one-way analysis of variance and Fisher's protected least significant difference tests, P < .05), but there was no significant difference in either the angle or length of the ET between the OME and normal children groups (P > .05). In the OME and normal children groups, the angle was observed to constantly increase with age, and the values were found to be within the range of the adult size in all the patients older than 7.5 years and 7.7 years in the OME children group and the normal children group, respectively. As well as the angle, the lengths were observed to constantly increase with age, but the increase appeared to be greater at a younger age (until approximately 3 to 4 years) than at an older age, and the values were found to be within the range of the adult size in all the patients older than 6.8 years and 7.7 years in the OME children group and the normal children group, respectively. Conclusion: The angle and length of the ET are more horizontal and shorter in infants than in adults. However, there is no statistical difference between the angle and length of the ET in infants with and without OME. These results lead us to believe that a short and horizontal ET may not be a main etiologic factor related to high susceptibility to OME in infants and children. [source] Effect of apolipoprotein E on biomarkers of amyloid load and neuronal pathology in Alzheimer diseaseANNALS OF NEUROLOGY, Issue 3 2010Prashanthi Vemuri PhD Objective To study the effect of apolipoprotein E ,4 status on biomarkers of neurodegeneration (atrophy on magnetic resonance imaging [MRI]), neuronal injury (cerebrospinal fluid [CSF] t-tau), and brain A, amyloid load (CSF A,1,42) in cognitively normal subjects (CN), amnestic subjects with mild cognitive impairment (aMCI), and patients with Alzheimer disease (AD). Methods We included all 399 subjects (109 CN, 192 aMCI, 98 AD) from the Alzheimer's Disease Neuroimaging Initiative study with baseline CSF and MRI scans. Structural Abnormality Index (STAND) scores, which reflect the degree of AD-like anatomic features on MRI, were computed for each subject. Results A clear ,4 allele dose effect was seen on CSF A,1,42 levels within each clinical group. In addition, the proportion of the variability in A,1,42 levels explained by APOE ,4 dose was significantly greater than the proportion of the variability explained by clinical diagnosis. On the other hand, the proportion of the variability in CSF t-tau and MRI atrophy explained by clinical diagnosis was greater than the proportion of the variability explained by APOE ,4 dose; however, this effect was only significant for STAND scores. Interpretation Low CSF A,1,42 (surrogate for A, amyloid load) is more closely linked to the presence of APOE ,4 than to clinical status. In contrast, MRI atrophy (surrogate for neurodegeneration) is closely linked with cognitive impairment, whereas its association with APOE ,4 is weaker. The data in this paper support a model of AD in which CSF A,1,42 is the earliest of the 3 biomarkers examined to become abnormal in both APOE carriers and noncarriers. ANN NEUROL 2010;67:308,316 [source] Transcatheter closure of high-risk muscular ventricular septal defects with the CardioSEAL occluder: Initial report from the CardioSEAL VSD RegistryCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 5 2007D. Scott Lim MD Abstract Objectives: The CardioSEAL VSD registry was created to track safety of the device to close high-risk Ventricular Septal Defect (VSD). Background: This is the first report from the multi-centered CardioSEAL VSD registry reviewing demographics and initial results. Methods: Centers recruited patients with VSD who were high-risk for surgery due to medical condition or anatomic features. Results: 18 centers contributed data on 55 high-risk patients who had 61 VSD-occlusion procedures, with age of range of 5 days to 65 years and using one to six devices. Implantation approach was transvenous in 48, perventricular in five, and by combined approach in two patients. Ninety-two percent of intended VSD device implants were judged successful. Twenty-two patients had single VSD closed by single device in 18 and by two devices in four patients. All patients <8 kg underwent perventricular device implantation. Thirty-three patients had multiple VSDs which were closed by a single device in 23, and multiple devices in 10. At discharge echocardiography showed total residual flow through all VSDs in which devices were used was classified as "Small" or less in 74%, "More than small" in 11%, and "Uncertain" in 15%. Eight major adverse events occurred in 5/61 cases (8% event rate), with 3/81 devices embolized (4% embolization rate), 5/81 devices surgically explanted (6% explant rate), and no deaths judged to be procedure-related. Conclusion: This initial report from the multi-centered CardioSEAL VSD registry demonstrates the safety of the device to close high-risk VSDs. © 2007 Wiley-Liss, Inc. [source] High-resolution 8 Tesla imaging of the formalin-fixed normal human hippocampusCLINICAL ANATOMY, Issue 2 2005Donald W. Chakeres Abstract The purpose of this study was to evaluate the capacity of high-resolution magnetic resonance imaging (MRI) to visualize the normal anatomic features of the human hippocampus in vitro, using high field imaging equipment, parameters, and acquisition times appropriate for imaging human subjects in vivo. This research compared high field, high-resolution MRI of formalin-fixed normal human hippocampus specimens to histologic sectioning of the same hippocampus samples. Four specimens were evaluated using an 8 Tesla (T), 80 cm bore whole-body MRI scanner equipped with a 12.7 cm single strut transverse electromagnetic resonator (TEM) coil. Hahn spin echo images were acquired with a repetition time (TR) of 800 msec, echo times (TE) of 20, 50, 90, and 134 msec, and an acquisition time (TA) of 3.25 min. The image quality was superb with demonstration of most of the features of the hippocampus. High field, high-resolution MRI can be used to depict multiple layers of the formalin-fixed human hippocampus in vitro using an 8 T whole-body scanner, a TEM coil, and short acquisition times compatible with human imaging in vivo. Clin. Anat. 18:88,91, 2005. © 2005 Wiley-Liss, Inc. [source] | |||||||||||||