Janssen Natasja N Y, Ter Beek Leon C, Loo Claudette E, Winter-Warnars Gonneke, Lange Charlotte A H, van Loveren Marjolein, Alderliesten Tanja, Sonke Jan-Jakob, Nijkamp Jasper
Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, Amsterdam, The Netherlands.
Department of Radiology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
Acad Radiol. 2017 Jul;24(7):818-825. doi: 10.1016/j.acra.2017.01.003. Epub 2017 Feb 27.
This study aims to evaluate if navigator-echo respiratory-triggered magnetic resonance acquisition can acquire supine high-quality breast magnetic resonance imaging (MRI).
Supine respiratory-triggered magnetic resonance imaging (Trig-MRI) was compared to supine non-Trig-MRI to evaluate breathing-induced motion artifacts (group 1), and to conventional prone non-Trig-MRI (group 2, 16-channel breast coil), all at 3T. A 32-channel thorax coil was placed on top of a cover to prevent breast deformation. Ten volunteers were scanned in each group, including one patient. The acquisition time was recorded. Image quality was compared by visual examination and by calculation of signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and image sharpness (IS).
Scan time increased from 56.5 seconds (non-Trig-MRI) to an average of 306 seconds with supine Trig-MRI (range: 120-540 seconds). In group 1, the median values (interquartile range) of SNR, CNR, and IS improved from 11.5 (6.0), 7.3 (3.1), and 0.23 (0.2) cm on supine non-Trig-MRI to 38.1 (29.1), 32.8 (29.7), and 0.12 (0) cm (all P < 0.01) on supine Trig-MRI. All qualitative image parameters in group 1 improved on supine Trig-MRI (all P < 0.01). In group 2, SNR and CNR improved from 14.7 (6.8) and 12.6 (5.6) on prone non-Trig-MRI to 36.2 (12.2) and 32.7 (12.1) (both P < 0.01) on supine Trig-MRI. IS was similar: 0.10 (0) cm vs 0.11 (0) cm (P = 0.88).
Acquisition of high-quality supine breast MRI is possible when respiratory triggering is applied, in a similar setup as during subsequent treatment. Image quality improved when compared to supine non-triggered breast MRI and prone breast MRI, but at the cost of increased acquisition time.
本研究旨在评估导航回波呼吸触发磁共振采集能否获取仰卧位高质量乳腺磁共振成像（MRI）。
将仰卧位呼吸触发磁共振成像（Trig-MRI）与仰卧位非触发磁共振成像进行比较，以评估呼吸引起的运动伪影（第1组），并与传统俯卧位非触发磁共振成像（第2组，16通道乳腺线圈）进行比较，均在3T条件下进行。将一个32通道胸部线圈置于覆盖物上方以防止乳房变形。每组扫描10名志愿者，包括1名患者。记录采集时间。通过视觉检查以及计算信噪比（SNR）、对比噪声比（CNR）和图像清晰度（IS）来比较图像质量。
扫描时间从56.5秒（非触发磁共振成像）增加到仰卧位Trig-MRI的平均306秒（范围：120 - 540秒）。在第1组中，仰卧位非触发磁共振成像时SNR、CNR和IS的中位数（四分位间距）分别为11.5（6.0）、7.3（3.1）和0.23（0.2）cm，而在仰卧位Trig-MRI时分别提高到38.1（29.1）、32.8（29.7）和0.12（0）cm（所有P < 0.01）。第1组中所有定性图像参数在仰卧位Trig-MRI时均有所改善（所有P < 0.01）。在第2组中，俯卧位非触发磁共振成像时SNR和CNR分别为14.7（6.8）和12.6（5.6），在仰卧位Trig-MRI时分别提高到36.2（12.2）和32.7（12.1）（两者P < 0.01）。IS相似：0.10（0）cm对0.11（0）cm（P = 0.88）。
当应用呼吸触发时，在与后续治疗相似的设置下，有可能获取高质量的仰卧位乳腺MRI。与仰卧位非触发乳腺MRI和俯卧位乳腺MRI相比，图像质量有所提高，但代价是采集时间增加。
