Department of Diagnostic Radiology, University Hospital, RWTH Aachen University, Aachen, Germany.
Invest Radiol. 2010 Aug;45(8):477-83. doi: 10.1097/RLI.0b013e3181e53e38.
To develop a method for visualizing surgical textile implant (STI) with superparamagnetic iron oxides (SPIO), using magnetic resonance imaging (MRI). Therefore, positive-contrast inversion-recovery with on-resonant water suppression (IRON) was applied and its properties were evaluated in vitro.
STI with different concentrations of SPIO integrated into the base material were produced. Imaging was performed on a clinical 1.5 Tesla scanner, using conventional balanced gradient echo sequences (SSFP), T2*-weighted sequences, and IRON-imaging. In vitro experiments were conducted in an agarose phantom. On MR-images, contrast-to-noise-ratios, and the dimensions of the implant were assessed.
Conventional MRI exhibited SPIO-loaded STI as signal voids. Using IRON, the mesh was clearly exhibited hyperintensely with suppression of on-resonant background signals with a distinct differentiation to other sources of off-resonances. Concentrations of approximately 9 mg/g led to best positive contrast and highest contrast-to-noise-ratios using IRON. Depending on B0-orientation, phase encoding direction and the STI's SPIO-load, the IRON-signal showed a characteristic pattern and an overestimation of STI size up to 4.6 mm.
The integration of SPIOs into the base material combined with IRON is a feasible approach to visualize STI with MRI. This method could help to identify mesh-related problems in time and to reduce the need for surgical revision.
开发一种使用超顺磁氧化铁 (SPIO) 可视化手术纺织植入物 (STI) 的方法,使用磁共振成像 (MRI)。因此,应用了基于共振水抑制的正对比反转恢复 (IRON),并在体外对其性能进行了评估。
制作了具有不同浓度 SPIO 整合到基底材料中的 STI。使用常规的平衡梯度回波序列 (SSFP)、T2*-加权序列和 IRON 成像在临床 1.5T 扫描仪上进行成像。在琼脂糖体模中进行体外实验。在 MR 图像上评估对比噪声比和植入物的尺寸。
常规 MRI 显示负载 SPIO 的 STI 为信号缺失。使用 IRON,网格清晰地呈现出高强度,同时抑制了共振背景信号,与其他非共振源有明显的区别。使用 IRON 时,约 9mg/g 的浓度可获得最佳的正对比和最高的对比噪声比。IRON 信号取决于 B0 方向、相位编码方向和 STI 的 SPIO 负载,表现出特征性的模式,并高估 STI 尺寸高达 4.6mm。
将 SPIO 整合到基底材料中并结合 IRON 是一种使用 MRI 可视化 STI 的可行方法。该方法有助于及时识别与网片相关的问题,并减少手术修正的需求。