Zaccagnino Ethan, Devincent Craig, Leelakanok Nattinee, Phelps Andrew S, Zapala Matthew, Worters Pauline Wong, Courtier Jesse
University of California San Francisco, San Francisco, CA, United States.
Radiology, UCSF Benioff Children's Hospital, San Francisco, CA, United States.
Clin Imaging. 2019 Jan-Feb;53:12-16. doi: 10.1016/j.clinimag.2018.09.014. Epub 2018 Sep 26.
Elevated acoustic noise during Magnetic Resonance Imaging (MRI) has been associated with patient anxiety and altered cochlear function. Acoustic Reduction Technique (ART) T2 weighted (T2w) periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) has been studied in brain MR but not abdominopelvic imaging. The purpose of our study was to evaluate the image quality and acoustic noise level of ART T2w PROPELLER sequence in comparison with the conventional T2w PROPELLER sequence in pediatric abdomino-pelvic imaging.
Eleven consecutive pediatric patients undergoing abdomino-pelvic MRI were scanned on a 3 Tesla magnet using standard and ART T2w PROPELLER sequences. After scanning completion, objective sound level measurements were performed with a sound level meter and microphone. Mann-Whitney U test was used for a non-parametric two-tailed statistical analysis of acoustics, image rating and scan time with significance level set to 0.05. Overall inter-rater agreement was calculated using Cohen's kappa coefficient.
Eleven pediatric patients (4 females and 7 males) between 26 days and 18 years of age (mean = 10.0, SD = 5.8) were included. ART T2w produced lower levels of acoustic noise than standard technique in a comparison of mean decibel readings from eleven trials of standard and ART T2w (p value = 0.00008). Streak artifacts were rated greater in ART T2w by both raters (p-value = 0.00278 and 0.00252). There was no significant difference in bile duct blurring, respiratory ghosting, pulsation, fat suppression or hepatic parenchymal depiction.
Presence of additional streaking artifacts should be considered along with the benefit of reduced acoustic noise from ART T2w.
磁共振成像（MRI）过程中升高的噪音与患者焦虑及耳蜗功能改变有关。声学降噪技术（ART）T2加权（T2w）周期性旋转重叠平行线增强重建（PROPELLER）序列已在脑部MRI中得到研究，但在腹部盆腔成像中尚未见报道。我们研究的目的是在儿科腹部盆腔成像中，将ART T2w PROPELLER序列与传统T2w PROPELLER序列相比较，评估其图像质量和声噪水平。
连续11例接受腹部盆腔MRI检查的儿科患者在3特斯拉磁体上使用标准及ART T2w PROPELLER序列进行扫描。扫描完成后，使用声级计和麦克风进行客观声级测量。采用曼-惠特尼U检验对声学、图像评分及扫描时间进行非参数双尾统计分析，显著性水平设定为0.05。使用科恩kappa系数计算评分者间的总体一致性。
纳入11例年龄在26天至18岁之间（平均=10.0，标准差=5.8）的儿科患者（4例女性，7例男性）。在对标准及ART T2w的11次试验的平均分贝读数比较中，ART T2w产生的声学噪音水平低于标准技术（p值=0.00008）。两位评分者均认为ART T2w中的条纹伪影更明显（p值分别为0.00278和0.00252）。在胆管模糊、呼吸伪影、搏动、脂肪抑制或肝实质显示方面无显著差异。
在考虑ART T2w降低声学噪音益处的同时，应注意其存在额外条纹伪影的情况。
