Stein Thomas, von Zur Muhlen Constantin, Verloh Niklas, Schürmann Till, Krauss Tobias, Soschynski Martin, Westermann Dirk, Taron Jana, Can Elif, Schlett Christopher L, Bamberg Fabian, Schuppert Christopher, Hagar Muhammad Taha
Medical Center-University of Freiburg Faculty of Medicine, Department of Diagnostic and Interventional Radiology, Freiburg, Germany.
Medical Center-University of Freiburg Faculty of Medicine, Department of Cardiology and Angiology, Freiburg, Germany.
Diagn Interv Radiol. 2025 Jan 1;31(1):29-38. doi: 10.4274/dir.2024.242893. Epub 2024 Oct 21.
The study aimed to assess the feasibility and image quality of dual-source photon-counting detector computed tomography (PCD-CT) in evaluating small-sized coronary artery stents with respect to different acquisition modes in a phantom model.
Utilizing a phantom setup mimicking the average patient's water-equivalent diameter, we examined six distinct coronary stents inflated in a silicon tube, with stent sizes ranging from 2.0 to 3.5 mm, applying four different CT acquisition modes of a dual-source PCD-CT scanner: "high-pitch," "sequential," "spiral" (each with collimation of 144 × 0.4 mm and full spectral information), and "ultra-high-resolution (UHR)" (collimation of 120 × 0.2 mm and no spectral information). Image quality and diagnostic confidence were assessed using subjective measures, including a 4-point visual grading scale (4 = excellent; 1 = non-diagnostic) utilized by two independent radiologists, and objective measures, including the full width at half maximum (FWHM).
A total of 24 scans were acquired, and all were included in the analysis. Among all CT acquisition modes, the highest image quality was obtained for the UHR mode [median score: 4 (interquartile range (IQR): 3.67-4.00)] ( = 0.0015, with 37.5% rated as "excellent"), followed by the sequential mode [median score: 3.5 (IQR: 2.84-4.00)], = 0.0326 and the spiral mode [median score: 3.0 (IQR: 2.53-3.47), > 0.05]. The lowest image quality was observed for the high-pitch mode [median score: 2 (IQR: 1- 3), = 0.028]. Similarly, diagnostic confidence for evaluating stent patency was highest for UHR and lowest for high-pitch ( < 0.001, respectively). Measurement of stent dimensions was accurate for all acquisition modes, with the UHR mode showing highest robustness (FWHM for sequential: 0.926 ± 0.061 vs. high-pitch: 0.990 ± 0.083 vs. spiral: 0.962 ± 0.085 vs. UHR: 0.941 ± 0.036, = non-significant, respectively).
Assessing small-sized coronary stents using PCD-CT technology is feasible. The UHR mode offers superior image quality and diagnostic confidence, while all modes show consistent and accurate measurements.
These findings highlight the potential of PCD-CT technology, particularly the UHR mode, to enhance non-invasive coronary stent evaluation. Confirmatory research is necessary to influence the guidelines, which recommend cardiac CT only for stents of 3 mm or larger.
本研究旨在评估双源光子计数探测器计算机断层扫描（PCD-CT）在体模模型中针对不同采集模式评估小尺寸冠状动脉支架的可行性和图像质量。
利用模拟平均患者水等效直径的体模设置，我们检查了在硅胶管中充气的六个不同的冠状动脉支架，支架尺寸范围为2.0至3.5毫米，应用双源PCD-CT扫描仪的四种不同CT采集模式：“高螺距”、“序列”、“螺旋”（每种模式的准直为144×0.4毫米且具有全光谱信息）以及“超高分辨率（UHR）”（准直为120×0.2毫米且无光谱信息）。使用主观测量方法评估图像质量和诊断信心，包括由两名独立放射科医生使用的4分视觉分级量表（4 = 优秀；1 = 无法诊断），以及客观测量方法，包括半高宽（FWHM）。
共采集了24次扫描，所有扫描均纳入分析。在所有CT采集模式中，UHR模式获得的图像质量最高[中位数评分：4（四分位间距（IQR）：3.67 - 4.00）]（ = 0.0015，37.5%被评为“优秀”），其次是序列模式[中位数评分：3.5（IQR：
