快速计算软件用于修正的 Look-Locker 反转恢复（MOLLI）T1 映射。

Fast calculation software for modified Look-Locker inversion recovery (MOLLI) T1 mapping.

机构信息

Clinical Research Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.

Department of Electronic Engineering, Sogang University, Seoul, South Korea.

出版信息

BMC Med Imaging. 2021 Feb 12;21(1):26. doi: 10.1186/s12880-021-00558-8.

DOI:10.1186/s12880-021-00558-8

PMID:33579214

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7881681/

Abstract

BACKGROUND

The purpose of this study was to develop a software tool and evaluate different T1 map calculation methods in terms of computation time in cardiac magnetic resonance imaging.

METHODS

The modified Look-Locker inversion recovery (MOLLI) sequence was used to acquire multiple inversion time (TI) images for pre- and post-contrast T1 mapping. The T1 map calculation involved pixel-wise curve fitting based on the T1 relaxation model. A variety of methods were evaluated using data from 30 subjects for computational efficiency: MRmap, python Levenberg-Marquardt (LM), python reduced-dimension (RD) non-linear least square, C++ single- and multi-core LM, and C++ single- and multi-core RD.

RESULTS

Median (interquartile range) computation time was 126 s (98-141) for the publicly available software MRmap, 261 s (249-282) for python LM, 77 s (74-80) for python RD, 3.4 s (3.1-3.6) for C++ multi-core LM, and 1.9 s (1.9-2.0) for C++ multi-core RD. The fastest C++ multi-core RD and the publicly available MRmap showed good agreement of myocardial T1 values, resulting in 95% Bland-Altman limits of agreement of (- 0.83 to 0.58 ms) and (- 6.57 to 7.36 ms) with mean differences of - 0.13 ms and 0.39 ms, for the pre- and post-contrast, respectively.

CONCLUSION

The C++ multi-core RD was the fastest method on a regular eight-core personal computer for pre- or post-contrast T1 map calculation. The presented software tool (fT1fit) facilitated rapid T1 map and extracellular volume fraction map calculations.

摘要

背景

本研究旨在开发一款软件工具，并评估不同的 T1 图谱计算方法在心脏磁共振成像中的计算时间。

方法

使用改良 Look-Locker 反转恢复（MOLLI）序列采集多个反转时间（TI）图像进行对比前和对比后 T1 映射。T1 图谱计算涉及基于 T1 弛豫模型的像素级曲线拟合。使用 30 名受试者的数据评估了多种方法的计算效率：MRmap、python Levenberg-Marquardt（LM）、python 降维（RD）非线性最小二乘、C++ 单核和多核 LM 以及 C++ 单核和多核 RD。

结果

公开可用软件 MRmap 的计算时间中位数（四分位距）为 126 秒（98-141），python LM 为 261 秒（249-282），python RD 为 77 秒（74-80），C++ 多核 LM 为 3.4 秒（3.1-3.6），C++ 多核 RD 为 1.9 秒（1.9-2.0）。最快的 C++ 多核 RD 和公开可用的 MRmap 显示出良好的心肌 T1 值一致性，导致对比前和对比后的 95% Bland-Altman 一致性界限分别为（-0.83 至 0.58 毫秒）和（-6.57 至 7.36 毫秒），平均差异分别为-0.13 毫秒和 0.39 毫秒。