Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA.
Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN, USA.
J Healthc Eng. 2017;2017:5369385. doi: 10.1155/2017/5369385. Epub 2017 Aug 28.
To evaluate a new postprocessing framework that eliminates arterial vessel signal contributions in the quantification of normalized visible venous volume (NVVV, a ratio between venous and brain volume) in susceptibility-weighted imaging (SWI) exams in patients with sickle cell disease (SCD).
We conducted a retrospective study and qualitatively reviewed for hypointense arterial vessel contamination in SWI exams from 21 children with SCD. We developed a postprocessing framework using magnetic resonance angiography in combination with SWI to provide a more accurate quantification of NVVV. NVVV was calculated before and after removing arterial vessel contributions to determine the error from hypointense arterial vessels in quantifying NVVV.
Hypointense arterial vessel contamination was observed in 86% SWI exams and was successfully corrected by the proposed method. The contributions of hypointense arterial vessels in the original SWI were significant and accounted for approximately 33% of the NVVV [uncorrected NVVV = 0.012 ± 0.005 versus corrected NVVV = 0.008 ± 0.003 (mean ± SD), < 0.01].
Hypointense arterial vessel contamination occurred in the majority of SWI exams and led to a sizeable overestimation of the visible venous volume. A prospective longitudinal study is needed to evaluate if quantitation of NVVV was improved and to assess the role of NVVV as a biomarker of SCD severity or stroke risk.
评估一种新的后处理框架，该框架可消除镰状细胞病（SCD）患者磁共振磁敏感加权成像（SWI）检查中静脉归一化可视体积（NVVV，静脉与脑容量的比值）定量分析中动脉信号的影响。
我们进行了一项回顾性研究，对 21 例 SCD 患者的 SWI 检查中低信号动脉血管污染进行了定性评估。我们开发了一种后处理框架，将磁共振血管造影与 SWI 相结合，以更准确地定量 NVVV。在去除动脉血管贡献后计算 NVVV，以确定在定量 NVVV 时低信号动脉血管的误差。
86%的 SWI 检查中观察到低信号动脉血管污染，且该方法可成功校正。原始 SWI 中低信号动脉血管的贡献非常显著，占 NVVV 的约 33%[未校正的 NVVV=0.012±0.005 与校正的 NVVV=0.008±0.003（平均值±标准差），<0.01]。
大多数 SWI 检查中均存在低信号动脉血管污染，导致可视静脉体积的明显高估。需要前瞻性纵向研究来评估 NVVV 的定量是否得到改善，并评估 NVVV 作为 SCD 严重程度或中风风险的生物标志物的作用。
