DYNAMIC RANGE CONSIDERATIONS FOR MRI

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。大型阵列3D数据集的图像质量通常受到16位模数转换器（ADC）的限制，它只能表示65536个单独的步骤，这对于256x256片是足够的，但对于更大的3D数据集，该ADC会产生很大的误差源。由于大部分信号位于低频数据中，高频空间的小信号表现不佳，导致高频对比度的损失。为了尽量减少这种错误，我们建议分割k空间的采集，以允许高频空间用更高的增益编码，而低频空间用更低的增益编码，以防止饱和。本实验的目标是通过放大高频信号来提高图像对比度和边界，在不产生任何额外的时间延迟的情况下，显示比常规获取的图像更精细的细节。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The image quality of large array 3D data sets is often limited by the 16-bit analog to digital converter (ADC), which is only capable of representing 65536 individual steps, which are adequate for a 256x256 slice, but for larger 3D data sets, this ADC creates a large source of error. Since the majority of the signal is located in the low-frequency data, the small signal of the high-frequency space is poorly represented, which results in a loss of high-frequency contrast. To minimize this error, we propose segmenting the acquisition of the k-space to allow the high-frequency space to be encoded with a higher gain, while the low-frequency space is encoded with a lower gain to prevent saturation. The goal of this experiment is to improve image contrast and boundaries by amplifying the high frequency signal, revealing finer details than the regularly acquired image without incurring any additional time delays.