Simon Gerhard H, Raatschen Hans-Juergen, Wendland Michael F, von Vopelius-Feldt Johannes, Fu Yanjun, Chen Mei-Hsiu, Daldrup-Link Heike E
University of California at San Francisco Medical Center, Department of Radiology, S-372, Center for Pharmaceutical and Molecular Imaging, 513 Parnassus Avenue, San Francisco, CA 94143, USA.
Acad Radiol. 2005 Sep;12(9):1190-7. doi: 10.1016/j.acra.2005.05.014.
The objective is to compare three different ultrasmall superparamagnetic iron oxides (USPIOs) for magnetic resonance (MR) imaging of normal bone marrow in rodents.
Femoral bone marrow in 18 Sprague-Dawley rats was examined by using MR imaging before and up to 2 and 24 hours postinjection (PI) of 200 mumol of Fe/kg of SHU555C (n = 6), ferumoxtran-10 (n = 6), or ferumoxytol (n = 6), using T1-weighted (50 ms/1.7 ms/60 degrees = repetition time [TR]/echo time [TE]/flip angle) and T2*-weighted (100 ms/15 ms/38 degrees = TR/TE/flip angle) three-dimensional spoiled gradient recalled echo sequences. USPIO-induced bone marrow was evaluated qualitatively and quantified as signal-to-noise ratio (SNR) and change in signal intensity (DeltaSI) values. A mixed-effect model was fitted to the SNR and DeltaSI values, and differences among USPIOs were tested for significance by using F tests.
At 2 hours PI, all three USPIOs showed marked positive signal enhancement on T1-weighted images and a corresponding marked signal loss on T2*-weighted images. At 24 hours PI, the T1 effect of all three USPIOs disappeared, whereas T2*-weighted images showed persistent signal loss on SHU555C and ferumoxytol-enhanced MR images, but not ferumoxtran-10-enhanced MR images. Corresponding SNR and DeltaSI values on T2*-weighted MR images at 24 hours PI were significantly different from baseline for SHU555C and ferumoxytol, but not ferumoxtran-10.
All three USPIO contrast agents, ferumoxtran-10, ferumoxytol, and SHU555C, can be applied for MR imaging of bone marrow. Ferumoxtran-10 apparently reveals a different kinetic behavior in bone marrow than ferumoxytol and SHU555C.
目的是比较三种不同的超小超顺磁性氧化铁（USPIO）用于啮齿动物正常骨髓的磁共振（MR）成像。
对18只Sprague-Dawley大鼠的股骨骨髓进行MR成像检查，在注射200 μmol Fe/kg的SHU555C（n = 6）、ferumoxtran-10（n = 6）或ferumoxytol（n = 6）之前以及注射后2小时和24小时进行，使用T1加权（50 ms/1.7 ms/60° = 重复时间[TR]/回波时间[TE]/翻转角）和T2*加权（100 ms/15 ms/38° = TR/TE/翻转角）三维扰相梯度回波序列。对USPIO诱导的骨髓进行定性评估，并量化为信噪比（SNR）和信号强度变化（DeltaSI）值。对SNR和DeltaSI值拟合混合效应模型，并使用F检验测试USPIO之间的差异是否具有显著性。
在注射后2小时，所有三种USPIO在T1加权图像上均显示出明显的正信号增强，在T2加权图像上相应地出现明显的信号丢失。在注射后24小时，所有三种USPIO的T1效应消失，而T2加权图像在SHU555C和ferumoxytol增强的MR图像上显示持续的信号丢失，但在ferumoxtran-10增强的MR图像上未显示。注射后24小时T2*加权MR图像上相应的SNR和DeltaSI值对于SHU555C和ferumoxytol与基线相比有显著差异，但对于ferumoxtran-10则无显著差异。
所有三种USPIO造影剂，即ferumoxtran-10、ferumoxytol和SHU555C，均可用于骨髓的MR成像。Ferumoxtran-10在骨髓中表现出与ferumoxytol和SHU555C不同的动力学行为。
