Konar Amaresha Shridhar, Vajuvalli Nithin N, Rao Rashmi, Jain Divya, Ramesh Babu D R, Geethanath Sairam
Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, USA; Medical Imaging Research Centre, Dayananda Sagar Institutions, Bangalore, India.
Medical Imaging Research Centre, Dayananda Sagar Institutions, Bangalore, India.
Magn Reson Imaging. 2020 Apr;67:18-23. doi: 10.1016/j.mri.2019.11.014. Epub 2019 Nov 18.
Magnetic Resonance Imaging (MRI) provides excellent soft tissue contrast with one significant limitation of slow data acquisition. Dynamic Contrast Enhanced MRI (DCE-MRI) is one of the widely employed techniques to estimate tumor tissue physiological parameters using contrast agents. DCE-MRI data acquisition and reconstruction requires high spatiotemporal resolution, especially during the post-contrast phase. The region of Interest Compressed Sensing (ROICS) is based on Compressed Sensing (CS) framework and works on the hypothesis that limiting CS to an ROI can achieve superior CS performance. In this work, ROICS has been demonstrated on breast DCE-MRI data at chosen acceleration factors and the results are compared with conventional CS implementation. Normalized Root Mean Square Error (NRMSE) was calculated to compare ROICS with CS quantitatively. CS and ROICS reconstructed images were used to compare K and v values derived using standard Tofts Model (TM). This also validated the superior performance of ROICS over conventional CS. ROICS generated Concentration Time Curves (CTC's) at chosen acceleration factors follow similar trend as the ground truth data as compared to CS. Both qualitative and quantitative analyses show that ROICS outperforms CS particularly at acceleration factors of 5× and above.
磁共振成像(MRI)能提供出色的软组织对比度,但存在数据采集速度慢这一显著局限性。动态对比增强磁共振成像(DCE-MRI)是广泛应用的利用造影剂估计肿瘤组织生理参数的技术之一。DCE-MRI数据采集和重建需要高时空分辨率,尤其是在造影剂注射后的阶段。感兴趣区域压缩感知(ROICS)基于压缩感知(CS)框架,其工作假设是将CS限制在感兴趣区域(ROI)可实现更优的CS性能。在这项工作中,已在选定加速因子下对乳腺DCE-MRI数据进行了ROICS测试,并将结果与传统CS实现方式进行了比较。计算归一化均方根误差(NRMSE)以定量比较ROICS和CS。使用CS和ROICS重建图像来比较通过标准Tofts模型(TM)得出的K值和v值。这也验证了ROICS相较于传统CS的优越性能。与CS相比,ROICS在选定加速因子下生成的浓度-时间曲线(CTC)与真实数据遵循相似趋势。定性和定量分析均表明,ROICS尤其在5倍及以上的加速因子下优于CS。