Miah Tayaba, Gunda Rithvik, Greil Gerald, Hussain Mohammad, Zou Qing
Division of Cardiology, Department of Pediatrics, UT Southwestern Medical Center, Dallas, Texas, United States of America.
Department of Radiology, UT Southwestern Medical Center, Dallas, Texas, United States of America.
PLoS One. 2025 Jan 31;20(1):e0318299. doi: 10.1371/journal.pone.0318299. eCollection 2025.
Balanced steady-state free processing (bSSFP) MR sequence has long been considered the gold standard method for ventricular function assessment (VFA), and normal values are based on this acquisition. However, bSSFP sequence suffers from susceptibility artifacts due to scenarios such as cardiac implants. The T1-TFE sequence, also known as ultrafast spoiled gradient sequence, is less affected by such susceptibility artifacts. While it is unclear if T1-TFE sequence yields similar VFA results as the bSSFP sequence.
To validate if the T1-TFE sequence, with an intravascular blood pool contrast agent, yields similar results for VFA as the gold-standard non-contrast bSSFP approach, so that the T1-TFE sequence can be used for VFA when bSSFP approach fails.
Two sets of images from two different sequences were utilized in this study. T1-TFE (with contrast) scans were used as one while bSSFP-derived images were used as the other. 37 pediatric patients were recruited into this study. Semi-automated software (cvi42) was used to segment and derive ventricular volumes. Image quality was objectively assessed by comparing signal-to-noise (SNR) and contrast-to-noise ratio (CNR) scores. Last, two expert readers provided a subjective analysis of image quality. Paired t-tests were used to assess significant differences in volumetric values (end-diastolic and end-systolic) between T1-TFE and bSSFP sequences. A Bland-Altman analysis evaluated potential bias and agreement between these sequences.
Ventricular function assessment via volumetric data analysis resulted in no statistically significant differences (P > 0.05), and high R2 values. SNR and CNR scores also presented with no statistically significant differences (P > 0.05), and nearly identical scores (SNR T1-TFE mean: 29.5 ± 3.1, SNR bSSFP mean: 28.8 ± 3.7, CNR T1-TFE mean: 28.8 ± 3.3, CNR bSSFP mean: 28.1 ± 4.0). Image quality assessment via expert subjective image analysis scores is consistent with the data. All Bland-Altman plots show good agreement and reveal no systematic bias or random error.
T1-TFE sequences in combination with Ferumoxytol allow reliable ventricular function assessment and overcome the limitations of traditional bSSFP MR sequences in this context.
平衡稳态自由处理（bSSFP）磁共振序列长期以来一直被视为评估心室功能（VFA）的金标准方法，正常值也基于此采集方式。然而，bSSFP序列会因心脏植入物等情况而出现磁化率伪影。T1-TFE序列，也称为超快扰相梯度序列，受此类磁化率伪影的影响较小。虽然尚不清楚T1-TFE序列是否能产生与bSSFP序列相似的VFA结果。
验证使用血管内血池造影剂的T1-TFE序列是否能产生与金标准非造影bSSFP方法相似的VFA结果，以便在bSSFP方法失败时可将T1-TFE序列用于VFA。
本研究使用了来自两个不同序列的两组图像。一组为T1-TFE（使用造影剂）扫描图像，另一组为bSSFP衍生图像。37名儿科患者被纳入本研究。使用半自动软件（cvi42）分割并得出心室容积。通过比较信噪比（SNR）和对比噪声比（CNR）分数对图像质量进行客观评估。最后，两位专家读者对图像质量进行主观分析。采用配对t检验评估T1-TFE和bSSFP序列在容积值（舒张末期和收缩末期）上的显著差异。Bland-Altman分析评估了这些序列之间的潜在偏差和一致性。
通过容积数据分析进行心室功能评估未发现统计学上的显著差异（P>0.05），且R2值较高。SNR和CNR分数也未显示出统计学上的显著差异（P>0.05），且分数几乎相同（T1-TFE序列的SNR平均值：29.5±3.1，bSSFP序列的SNR平均值：28.8±3.7，T1-TFE序列的CNR平均值：28.8±3.3，bSSFP序列的CNR平均值：28.1±4.0）。通过专家主观图像分析分数进行的图像质量评估与数据一致。所有Bland-Altman图均显示出良好的一致性，且未发现系统偏差或随机误差。
T1-TFE序列与菲洛托醇联合使用可实现可靠的心室功能评估，并克服了传统bSSFP磁共振序列在此方面的局限性。
