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981.
Winter L Kellman P Renz W Gräßl A Hezel F Thalhammer C von Knobelsdorff-Brenkenhoff F Tkachenko V Schulz-Menger J Niendorf T 《European radiology》2012,22(10):2211-2220
Objectives
To implement, examine, and compare three multichannel transmit/receive coil configurations for cardiovascular MR (CMR) at 7T.Methods
Three radiofrequency transmit-receive (TX/RX) coils with 4-, 8-, and 16-coil elements were used. Ten healthy volunteers (seven males, age 28?±?4?years) underwent CMR at 7T. For all three RX/TX coils, 2D CINE FLASH images of the heart were acquired. Cardiac chamber quantification, signal-to-noise ratio (SNR) analysis, parallel imaging performance assessment, and image quality scoring were performed.Results
Mean total examination time was 29?±?5?min. All images obtained with the 8- and 16-channel coils were diagnostic. No significant difference in ejection fraction (EF) (P?>?0.09) or left ventricular mass (LVM) (P?>?0.31) was observed between the coils. The 8- and 16-channel arrays yielded a higher mean SNR in the septum versus the 4-channel coil. The lowest geometry factors were found for the 16-channel coil (mean ± SD 2.3?±?0.5 for R?=?4). Image quality was rated significantly higher (P?0.04) for the 16-channel coil versus the 8- and 4-channel coils.Conclusions
All three coil configurations are suitable for CMR at 7.0T under routine circumstances. A larger number of coil elements enhances image quality and parallel imaging performance but does not impact the accuracy of cardiac chamber quantification.Key Points
? Cardiac chamber quantification using 7.0T magnetic resonance imaging is feasible. ? Examination times for cardiac chamber quantification at 7.0T match current clinical practice. ? Multichannel transceiver RF technology facilitates improved image quality and parallel imaging performance. ? Increasing the number of RF channels does not influence cardiac chamber quantification. 相似文献982.
Albrecht I. Schmid Vera B. Schrauwen‐Hinderling Martin Andreas Michael Wolzt Ewald Moser Michael Roden 《Magnetic resonance in medicine》2012,67(4):898-905
Alternate methods to quantify mitochondrial activity or function have been extensively used for studying insulin resistance and type 2 diabetes mellitus, namely saturation transfer and phosphocreatine (PCr) recovery. As these methods are in fact determining different parameters, this study aimed to compare saturation transfer results to PCr recovery measurements within the same group. Fifteen subjects underwent saturation transfer and ischemic exercise‐recovery experiments. PCr decrease during ischemia (Q), induced by cuff inflation, served as an additional measure of resting ATP (adenosine triphosphate) production. ATP synthetic rate (fATP) measured by saturation transfer (0.234 ± 0.043 mM/s) was greater than (Q = 0.0077 ± 0.0011 mM/s), but correlated well with Q (r = 0.63 P = 0.013). Parameters of PCr recovery correlated well with fATP (Qmax,lin: r = 0.71, P = 0.003, Qmax,ADP: r = 0.66, P = 0.007) and Q (Qmax,lin: r = 0.92, P = 0.000002, Qmax,ADP: r = 0.76, P = 0.001). In conclusion, although saturation transfer yields higher ATP synthetic rates than PCr decrease during ischemia, their significant correlation indicates that fATP can be used as a marker of mitochondrial activity. The finding that both Q and fATP correlate with PCr recovery kinetics suggests that skeletal muscle with greater maximal aerobic ATP synthetic rates is also metabolically more active at rest. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
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Joerg Heil Valerie Fuchs Michael Golatta Sarah Schott Markus Wallwiener Christoph Domschke Peter Sinn Michael P. Lux Christof Sohn Florian Schütz 《Breast care (Basel, Switzerland)》2012,7(5):364-369
Surgery is still a main therapeutic option in breast cancer treatment. Nowadays, methods of resection and reconstruction vary according to different tumors and patients. This review presents and discusses standards of care and arising questions on how radical primary breast cancer surgery should be according to different clinical situations. In most early breast cancer patients, breast conservation is the method of choice. The discussion on resection margins is still controversial as different studies show conflicting results. Modified radical mastectomy is the standard in locally advanced breast cancer patients, although there are different promising approaches to spare skin or even the nipple-areola complex. A sentinel node biopsy is the standard of care in clinically node-negative invasive breast cancer patients, whereas the significance of axillary lymphonodectomy seems to be questioned through a number of different findings. Although there are interesting findings to modify surgical approaches in very young or elderly breast cancer patients, it will always be an individualized approach if we do not adhere to current guidelines. Up to date, there are no special surgical procedures in BRCA mutation carriers or patients of high-risk families. 相似文献
987.
Pier?Francesco?AlesinaEmail author Jakob?Hinrichs Beate?Meier Kurt?W.?Schmid Hartmut?P.?H.?Neumann Martin?K.?Walz 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2012,397(2):233-238
Introduction
Cortical-sparing adrenalectomy in bilateral pheochromocytomas offers a postoperative corticoid-free course and has to be balanced against the risk of local recurrence. In this study we report our experience with the minimally invasive cortical-sparing adrenalectomy in patients with bilateral pheochromocytomas. 相似文献988.
989.
G Freckmann C Schmid K Ruhland A Baumstark C Haug 《Journal of diabetes science and technology》2012,6(4):938-946
Self-monitoring of blood glucose (SMBG) implicates a number of handling steps with the meter and the lancing device. Numerous user errors can occur during SMBG, and each step adds to the complexity of use. This report compares the required steps to perform SMBG of one fully integrated (the second generation of the Accu-Chek® Mobile), three partly integrated (Accu-Chek Compact Plus, Ascensia® Breeze®2, and Accu-Chek Aviva), and six conventional (Bayer Contour®, Bayer Contour USB, BGStar™, FreeStyle Lite®, OneTouch® Ultra® 2, and OneTouch Verio™Pro) systems. The results show that the fully integrated system reduces the number of steps to perform SMBG. The mean decrease is approximately 70% compared with the other systems. We assume that a reduction of handling steps also reduces the risk of potential user errors and improves the user-friendliness of the system. 相似文献
990.