Division of Neuroradiology, Joint Department of Medical Imaging, Toronto Western Hospital, Toronto, Ontario, Canada.
Division of Neuroradiology, Joint Department of Medical Imaging, Toronto Western Hospital, Toronto, Ontario, Canada.
Eur J Radiol. 2021 May;138:109645. doi: 10.1016/j.ejrad.2021.109645. Epub 2021 Mar 10.
Cone beam CT (CBCT) imaging assessment of acute ischemic stroke (AIS) patients with large-vessel occlusion (LVO) in the angiosuite may improve stroke workflow and decrease time to recanalization. In order for this workflow to gain widespread acceptance, current CBCT imaging needs further development to improve image quality. Our study aimed to compare the image quality of a new CBCT protocol performed directly in the angiosuite with imaging from multidetector CT as a gold standard.
AIS patients with an LVO who were candidates for endovascular treatment were prospectively included in this study. Following conventional multidetector CT (MDCT), patients underwent unenhanced cone beam CT (XperCT, Philips) imaging in the angiosuite, using two different protocols: a standard 20.8 s XperCT and/or an improved 10.4 s XperCT protocol. Images were evaluated using both qualitative and quantitative methods.
We included 65 patients in the study. Patients received CBCT imaging prior to endovascular treatment; 18 patients were assessed with a standard 20.8 s protocol scans and 47 with a newer 10.4 s scan. The quantitative analysis showed that the mean contrast-to-noise ratio (CNR) was significantly higher for the newer 10.4 s protocol compared with the 20.8 s protocol (2.08 +/- 0.64 vs. 1.15 +/- 0.27, p < 0.004) and the mean image noise was significantly lower for the 10.4 s XperCTs when compared with the 20.8 s XperCTs (6.30 +/- 1.34 vs. 7.82 +/- 2.03, p=<0.003). Qualitative analysis, including 6 measures of image quality, demonstrated that 74.1 % of the 10.4 s XperCT scans were ranked as 'Acceptable' for assessing parenchymal imaging in AIS patients(scoring 3-5 points on a 5-point Likert-scale), compared with 32.4 % of the standard 20.8 s XperCT and 100 % of the MDCT scans. Compared to the MDCT studies, 83 % of the 10.4 s XperCT scans were deemed sufficient image quality for a direct-to-angiosuite selection, compared to only 11 % for the standard 20.8 s scans. The largest image quality improvements included grey/white matter differentiation (59 % improvement), and reduction of image noise and artefacts (63 % & 50 % improvement, respectively).
Continued advances in cone-beam CT allow marked improvements in image quality for the assessment of brain parenchyma, which supports a direct-to-angiosuite approach for AIS patients eligible for thrombectomy treatment.
在血管内治疗单元（angiosuite）中对伴有大血管闭塞（LVO）的急性缺血性卒中（AIS）患者行锥形束 CT（CBCT）成像评估可能会改善卒中工作流程并缩短再通时间。为了使这种工作流程得到广泛认可，目前的 CBCT 成像需要进一步发展以提高图像质量。我们的研究旨在比较在血管内治疗单元中直接进行的新 CBCT 方案与作为金标准的多排 CT（MDCT）成像的图像质量。
本前瞻性研究纳入了符合血管内治疗条件的伴有 LVO 的 AIS 患者。在常规多排 CT（MDCT）后，患者在血管内治疗单元中进行未增强锥形束 CT（XperCT，飞利浦）成像，使用两种不同的方案：标准的 20.8 s XperCT 和/或改进的 10.4 s XperCT 方案。使用定性和定量方法评估图像。
本研究纳入了 65 例患者。患者在血管内治疗前接受 CBCT 成像；18 例患者接受标准的 20.8 s 方案扫描，47 例患者接受新的 10.4 s 扫描。定量分析显示，新的 10.4 s 方案的平均对比噪声比（CNR）明显高于 20.8 s 方案（2.08 +/- 0.64 比 1.15 +/- 0.27，p < 0.004），并且新的 10.4 s XperCT 的平均图像噪声明显低于 20.8 s XperCT（6.30 +/- 1.34 比 7.82 +/- 2.03，p < 0.003）。包括 6 项图像质量测量的定性分析表明，在评估 AIS 患者的实质成像时，74.1%的 10.4 s XperCT 扫描被评为“可接受”（5 分制 Likert 评分 3-5 分），而标准的 20.8 s XperCT 为 32.4%，MDCT 为 100%。与 MDCT 研究相比，新的 10.4 s XperCT 扫描中有 83%被认为具有直接进入血管内治疗单元的足够图像质量，而标准的 20.8 s XperCT 扫描仅有 11%。最大的图像质量改善包括灰/白质分化（提高 59%）和降低图像噪声和伪影（分别提高 63%和 50%）。
锥形束 CT 的持续进步允许对脑实质的评估显著提高图像质量，这支持了对适合血栓切除术治疗的 AIS 患者直接进入血管内治疗单元的方法。
