Fahrni Guillaume, Boccalini Sara, Lacombe Hugo, de Oliveira Fabien, Houmeau Angèle, Francart Florie, Villien Marjorie, Rotzinger David C, Robert Antoine, Douek Philippe, Si-Mohamed Salim A
Department of Diagnostic and Interventional Radiology, Cardiothoracic and Vascular Division, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.
University of Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS, Villeurbanne, France.
Eur Radiol. 2025 Jun;35(6):3042-3053. doi: 10.1007/s00330-024-11237-x. Epub 2024 Dec 11.
To assess the image quality of ultra-high-resolution (UHR) virtual monoenergetic images (VMIs) at 40 keV compared to 70 keV, using spectral photon-counting CT (SPCCT) and dual-layer dual-energy CT (DECT) for coronary computed tomography angiography (CCTA).
In this prospective IRB-approved study, 26 high-risk patients were included. CCTA was performed both with an SPCCT in UHR mode and with one of two DECT scanners (iQOn or CT7500) within 3 days. 40 keV and 70 keV VMIs were reconstructed for both modalities. Stenoses, blooming artefacts, and image quality were compared between all four reconstructions.
Twenty-six patients (4 women [15%]) and 28 coronary stenoses (mean stenosis of 56% ± 16%) were included. 40 keV SPCCT gave an overall higher quality score (5 [5, 5]) than 70 keV SPCCT (5 [4, 5], 40 keV DECT (4 [3, 4]) and 70 keV SPCCT (4 [4, 5]), p < 0.001). Less variability in stenosis measurement was found with SPCCT between 40 keV and 70 keV (bias: -1% ± 3%, LoA: 6%) compared with DECT (-6% ± 8%, LoA 16%). 40 keV SPCCT vs 40 keV DECT showed a -3% ± 6% bias, whereas 40 keV SPCCT vs 70 keV DECT showed a -8% ± 6% bias. From 70 keV to 40 keV, blooming artefacts did not increase with SPCCT (mean +2% ± 5%, p = 0.136) whereas they increased with DECT (mean +7% ± 6%, p = 0.005).
UHR 40 keV SPCCT VMIs outperformed 40 keV and 70 keV DECT VMIs for assessing coronary artery stenoses, with no impairment compared to 70 keV SPCCT VMIs.
Question Use of low virtual mono-energetic images at 40 keV using spectral dual-energy and photon-counting CT systems is not yet established for diagnosing coronary artery stenosis. Findings UHR 40 keV SPCCT enhances diagnostic accuracy in coronary artery assessment. Clinical relevance By combining spectral sensitivity with lower virtual mono-energetic imaging and ultra-high spatial resolution, SPCCT enhances coronary artery assessment, potentially leading to more accurate diagnoses and better patient outcomes in cardiovascular imaging.
使用光谱光子计数CT（SPCCT）和双层双能量CT（DECT）进行冠状动脉计算机断层扫描血管造影（CCTA），评估40keV与70keV相比的超高分辨率（UHR）虚拟单能图像（VMI）的图像质量。
在这项经机构审查委员会（IRB）批准的前瞻性研究中，纳入了26例高危患者。在3天内分别使用UHR模式的SPCCT和两台DECT扫描仪（iQOn或CT7500）之一进行CCTA。两种模式均重建40keV和70keV的VMI。比较所有四种重建图像的狭窄情况、伪影和图像质量。
纳入了26例患者（4名女性[15%]）和28处冠状动脉狭窄（平均狭窄率为56%±16%）。40keV的SPCCT总体质量评分（5[5,5]）高于70keV的SPCCT（5[4,5]）、40keV的DECT（4[3,4]）和70keV的DECT（4[4,5]），p<0.001。与DECT（-6%±8%，一致性界限[LoA]为16%）相比，SPCCT在40keV和70keV之间测量狭窄时的变异性较小（偏差：-1%±3%，LoA：6%）。40keV的SPCCT与40keV的DECT相比偏差为-3%±6%，而40keV的SPCCT与70keV的DECT相比偏差为-8%±6%。从70keV到40keV，SPCCT的伪影没有增加（平均增加2%±5%，p=0.136），而DECT的伪影增加了（平均增加7%±6%，p=0.005）。
在评估冠状动脉狭窄方面，UHR 40keV的SPCCT VMI优于40keV和70keV的DECT VMI，与70keV的SPCCT VMI相比无损害。
问题 使用光谱双能量和光子计数CT系统的40keV低虚拟单能图像诊断冠状动脉狭窄尚未确立。发现 UHR 40keV的SPCCT提高了冠状动脉评估的诊断准确性。临床意义 通过将光谱敏感性与更低的虚拟单能成像和超高空间分辨率相结合，SPCCT增强了冠状动脉评估，可能在心血管成像中带来更准确的诊断和更好的患者预后。
