From the Departments of Diagnostic Imaging and Nuclear Medicine.
Human Health Sciences.
Invest Radiol. 2021 Feb 1;56(2):69-77. doi: 10.1097/RLI.0000000000000708.
The aim of this study was to assess the accuracy, reliability, and cerebral microbleed (CMB) detection performance of 2-minute quantitative susceptibility mapping (QSM) from 3-dimensional echo-planar imaging (3D-EPI).
Gadolinium phantom study was conducted using 3D-EPI, single-echo time (TE), and multi-TE gradient-recalled echo (GRE) sequences on two 3-T magnetic resonance (MR) scanners to assess the accuracy between measured and theoretical susceptibility values. The institutional review board approved this prospective study, and 40 healthy volunteers were enrolled with written consent between April 2018 and October 2019. Each underwent 3D-EPI, single-TE, and multi-TE GRE sequences consecutively on one 3-T MR scanner, and QSMs were calculated to assess the reliability of 3D-EPI QSM. Intraclass correlation coefficient (ICC), linear regression, and Bland-Altman plots were calculated. Patients with CMB who underwent both 3D-EPI and GRE QSM scans were retrospectively enrolled. Two radiologists evaluated images independently, and Cohen κ coefficients were calculated to compare CMB detection performance.
Phantom study showed excellent validity of 3D-EPI QSM on both MR scanners: Skyra, R2 = 0.996, P < 0.001, ICC = 0.997, mean difference, -2 ppb (95% confidence interval [CI], -45 to 40 ppb); Prisma, R2 = 0.992, P < 0.001, ICC = 0.988, mean difference, 15 ppb (95% CI, -67 to 97 ppb). A human study of 40 healthy volunteers (59 ± 13 years, 25 women) showed excellent reliability with 3D-EPI QSM for both single-TE and multi-TE GRE (R2 = 0.981, P < 0.001, ICC = 0.988; R2 = 0.983, P < 0.001, ICC = 0.990, respectively), supported by a Bland-Altman mean difference of 4 ppb (95% CI, -15 to 23 ppb) for single-TE GRE and 3 ppb (95% CI, -15 to 20 ppb) for multi-TE GRE. The CMB detection performance evaluation from 38 patients (51 ± 20 years, 20 women) showed almost perfect agreement between 3D-EPI and GRE QSM for both raters (κ = 0.923 and 0.942, P < 0.001).
Faster QSM from 3D-EPI demonstrated excellent accuracy, reliability, and CMB detection performance.
本研究旨在评估基于三维回波平面成像（3D-EPI）的 2 分钟定量磁化率图（QSM）的准确性、可靠性和脑微出血（CMB）检测性能。
在两台 3T 磁共振（MR）扫描仪上，使用 3D-EPI、单回波时间（TE）和多 TE 梯度回波（GRE）序列进行钆造影剂体模研究，以评估测量值与理论磁化率值之间的准确性。本研究获得机构审查委员会批准，于 2018 年 4 月至 2019 年 10 月期间，40 名健康志愿者经书面同意后参与本前瞻性研究。所有志愿者均在一台 3T MR 扫描仪上连续进行 3D-EPI、单 TE 和多 TE GRE 序列检查，计算 QSM 以评估 3D-EPI QSM 的可靠性。计算组内相关系数（ICC）、线性回归和 Bland-Altman 图。回顾性纳入同时接受 3D-EPI 和 GRE QSM 扫描的 CMB 患者。两名放射科医生独立评估图像，计算 Cohen κ 系数以比较 CMB 检测性能。
体模研究显示，两台 MR 扫描仪上的 3D-EPI QSM 均具有优异的有效性：Skyra，R2 = 0.996，P < 0.001，ICC = 0.997，平均差值，-2 ppb（95%置信区间[CI]，-45 至 40 ppb）；Prisma，R2 = 0.992，P < 0.001，ICC = 0.988，平均差值，15 ppb（95% CI，-67 至 97 ppb）。对 40 名健康志愿者（59 ± 13 岁，25 名女性）的人体研究显示，3D-EPI QSM 对单 TE 和多 TE GRE 均具有优异的可靠性（R2 = 0.981，P < 0.001，ICC = 0.988；R2 = 0.983，P < 0.001，ICC = 0.990），单 TE GRE 的 Bland-Altman 平均差值为 4 ppb（95% CI，-15 至 23 ppb），多 TE GRE 的 Bland-Altman 平均差值为 3 ppb（95% CI，-15 至 20 ppb）。对 38 名患者（51 ± 20 岁，20 名女性）的 CMB 检测性能评估显示，两名阅片者的 3D-EPI 和 GRE QSM 之间几乎完全一致（κ = 0.923 和 0.942，P < 0.001）。
更快的 3D-EPI QSM 显示出优异的准确性、可靠性和 CMB 检测性能。
