Bucher Andreas M, Wichmann Julian L, Schoepf U Joseph, Wolla Christopher D, Canstein Christian, McQuiston Andrew D, Krazinski Aleksander W, De Cecco Carlo N, Meinel Felix G, Vogl Thomas J, Geyer Lucas L
Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Ashley River Tower, MSC 226, 25 Courtenay Drive, Charleston, SC, 29401, USA.
Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
Eur Radiol. 2016 Sep;26(9):3215-22. doi: 10.1007/s00330-015-4137-x. Epub 2015 Dec 9.
To assess quantitatively the impact of a novel reconstruction algorithm ("kernel") with beam-hardening correction (BHC) on beam-hardening artefacts of the myocardium at dual-energy CT myocardial perfusion imaging (DE-CTMPI).
Rest-series of DE-CTMPI examinations from 14 patients were retrospectively analyzed. Six image series were reconstructed for each patient: a) 100 kV, b) 140 kV, and c) linearly blended MIX0.5, each with BHC (D33f kernel) and without (D30f kernel). Seven hundred and fifty-six myocardial regions were assessed. Seven equal regions of interest divided the myocardium in the axial section. Three subdivisions were created within these regions in areas prone to BHA. Reports of SPECT studies performed within 30 days of CT examination were used to confirm the presence and location of true perfusion defects. Paired student t-test was used for statistical evaluation.
Overall mean myocardial attenuation was lower using BHC (D30f: 87.3 ± 24.1 HU; D33f: 85.5 ± 21.5 HU; p = 0.009). Overall relative difference from average myocardial attenuation (RDMA) was more homogeneous using BHC (D30f: -0.3 ± 11.4 %; D33f: 0.1 ± 10.1 %; p < 0.001). Changes in RDMA were greatest in the posterobasal myocardium (D30f: -16.2 ± 10.0 %; D33f: 3.4 ± 10.7 %; p < 0.001).
A dedicated reconstruction algorithm with BHC can significantly reduce beam-hardening artefacts in DE-CTMPI.
• Beam-hardening artefacts (BHA) cause interference with attenuation-based CT myocardial perfusion assessment (CTMPI). • BHA occur mostly in the posterobasal left ventricular wall. • Beam-hardening correction homogenized and decreased mean myocardial attenuation. • BHC can help avoid false-positive findings and increase specificity of static CTMPI.
定量评估一种具有束硬化校正（BHC）的新型重建算法（“内核”）对双能量CT心肌灌注成像（DE-CTMPI）中心肌束硬化伪影的影响。
回顾性分析14例患者的DE-CTMPI静息期检查系列。为每位患者重建六个图像系列：a）100 kV，b）140 kV，以及c）线性混合的MIX0.5，每个系列均有BHC（D33f内核）和无BHC（D30f内核）。评估756个心肌区域。七个等大的感兴趣区域将心肌在轴位上进行划分。在这些区域中易出现束硬化伪影（BHA）的区域内创建三个子区域。使用在CT检查30天内进行的SPECT研究报告来确认真正灌注缺损的存在和位置。采用配对学生t检验进行统计学评估。
使用BHC时总体平均心肌衰减较低（D30f：87.3±24.1 HU；D33f：85.5±21.5 HU；p = 0.009）。使用BHC时与平均心肌衰减的总体相对差异（RDMA）更均匀（D30f：-0.3±11.4%；D33f：0.1±10.1%；p < 0.001）。RDMA的变化在基底后心肌中最大（D30f：-16.2±10.0%；D33f：3.4±10.7%；p < 0.001）。
具有BHC的专用重建算法可显著减少DE-CTMPI中的束硬化伪影。
• 束硬化伪影（BHA）会干扰基于衰减的CT心肌灌注评估（CTMPI）。• BHA大多发生在左心室基底后壁。• 束硬化校正使平均心肌衰减均匀化并降低。• BHC有助于避免假阳性结果并提高静态CTMPI的特异性。
