Pinkernelle J G, Streitparth F, Rump J, Teichgräber U
Institut für Radiologie, Charité Univertätsmedizin Berlin.
Rofo. 2010 Apr;182(4):348-52. doi: 10.1055/s-0028-1109895. Epub 2009 Dec 14.
To demagnetize a PC mouse for interventional use in magnetic resonance imaging (MRI).
A mobile version of a wireless optical mouse at 2.470 Hz was modified in ways ranging from the replacement of magnetic components to the construction of new components. The magnetic force (Fm), the induction of susceptibility artifacts, and the signal-to-noise ratio (SNR) were determined. The modified mice at 1.0 T. were used in MR-guided interventions.
A final demagnetization down to 2 % (Fm = 9 N vs. Fm = 0.15 N) was achieved. Operating the device clinically caused no compromise in image quality. From a minimal distance of about 20 cm, even the non-modified mouse did not produce any susceptibility artifacts in gradient recalled imaging. The SNR was not reduced significantly (TSE 228 + or - 22,3 vs. 211 + or - 15; FFE 55 + or - 5,6 vs. 56 + or - 4,3). For over a year the modified mouse proved to be a reliable tool for the interventionalist to manipulate MRI.
Relatively inexpensive modifications of a standard USB mouse enable the interventionalist to work independently without a technical assistant and to take immediate advantage of multiplanar MR imaging during interventions.
使用于磁共振成像（MRI）介入操作的电脑鼠标消磁。
对一款频率为2.470 Hz的无线光学移动鼠标进行了多种改造，包括更换磁性部件以及构建新部件。测定了磁力（Fm）、磁化率伪影的感应以及信噪比（SNR）。在1.0 T场强下对改造后的鼠标进行了MR引导介入操作。
最终实现了降至2%的消磁效果（Fm = 9 N对比Fm = 0.15 N）。临床操作该设备未对图像质量造成损害。从约20 cm的最小距离起，即使是未改造的鼠标在梯度回波成像中也未产生任何磁化率伪影。信噪比未显著降低（快速自旋回波序列TSE 228 ± 22.3对比211 ± 15；快速小角度激发序列FFE 55 ± 5.6对比56 ± 4.3）。一年多来，改造后的鼠标被证明是介入医生在MRI操作中可靠的工具。
对标准USB鼠标进行相对低成本的改造，可使介入医生无需技术助手独立工作，并在介入操作过程中即时利用多平面MR成像。
