Toritani Hidetaka, Yoshida Kazuki, Hosokawa Takaaki, Tanabe Yuki, Yamamoto Yuta, Nishiyama Hikaru, Kido Tomoyuki, Kawaguchi Naoto, Matsuda Megumi, Nakano Shota, Miyazaki Shigehiro, Uetani Teruyoshi, Inaba Shinji, Yamaguchi Osamu, Kido Teruhito
From the Ehime University School of Medicine.
Department of Radiology, Ehime University Graduate School of Medicine, Toon City.
J Comput Assist Tomogr. 2025;49(1):85-92. doi: 10.1097/RCT.0000000000001652. Epub 2024 Aug 2.
This study evaluated the feasibility of a model-based iterative reconstruction technique (MBIR) tuned for the myocardium on myocardial computed tomography late enhancement (CT-LE).
Twenty-eight patients who underwent myocardial CT-LE and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) within 1 year were retrospectively enrolled. Myocardial CT-LE was performed using a 320-row CT with low tube voltage (80 kVp). Myocardial CT-LE images were scanned 7 min after CT angiography (CTA) without additional contrast medium. All myocardial CT-LE images were reconstructed with hybrid iterative reconstruction (HIR), conventional MBIR (MBIR_cardiac), and new MBIR tuned for the myocardium (MBIR_myo). Qualitative (5-grade scale) scores and quantitative parameters (signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]) were assessed as image quality. The sensitivity, specificity, and accuracy of myocardial CT-LE were evaluated at the segment level using an American Heart Association (AHA) 16-segment model, with LGE-MRI as a reference standard. These results were compared among the different CT image reconstructions.
In 28 patients with 448 segments, 160 segments were diagnosed with positive by LGE-MRI. In the qualitative assessment of myocardial CT-LE, the mean image quality scores were 2.9 ± 1.2 for HIR, 3.0 ± 1.1 for MBIR_cardiac, and 4.0 ± 1.0 for MBIR_myo. MBIR_myo showed a significantly higher score than HIR ( P < 0.001) and MBIR_cardiac ( P = 0.018). In the quantitative image quality assessment of myocardial CT-LE, the median image SNR was 10.3 (9.1-11.1) for HIR, 10.8 (9.8-12.1) for MBIR_cardiac, and 16.8 (15.7-18.4) for MBIR_myo. The median image CNR was 3.7 (3.0-4.6) for HIR, 3.8 (3.2-5.1) for MBIR_cardiac, and 6.4 (5.0-7.7) for MBIR_myo. MBIR_myo significantly improved the SNR and CNR of CT-LE compared to HIR and MBIR_cardiac ( P < 0.001). The sensitivity, specificity, and accuracy for the detection of myocardial CT-LE were 70%, 92%, and 84% for HIR; 71%, 92%, and 85% for MBIR_cardiac; and 84%, 92%, and 89% for MBIR_myo, respectively. MBIR_myo showed significantly higher image quality, sensitivity, and accuracy than the others ( P < 0.05).
MBIR tuned for myocardium improved image quality and diagnostic performance for myocardial CT-LE assessment.
本研究评估了一种针对心肌进行调整的基于模型的迭代重建技术（MBIR）在心肌计算机断层扫描延迟强化（CT-LE）中的可行性。
回顾性纳入28例在1年内接受心肌CT-LE和钆延迟强化（LGE）磁共振成像（MRI）的患者。使用低管电压（80 kVp）的320排CT进行心肌CT-LE检查。在CT血管造影（CTA）后7分钟，在不使用额外造影剂的情况下扫描心肌CT-LE图像。所有心肌CT-LE图像均采用混合迭代重建（HIR）、传统MBIR（MBIR_cardiac）和针对心肌调整的新MBIR（MBIR_myo）进行重建。将定性（5级评分）分数和定量参数（信噪比[SNR]和对比噪声比[CNR]）评估为图像质量。以LGE-MRI作为参考标准，使用美国心脏协会（AHA）16节段模型在节段水平评估心肌CT-LE的敏感性、特异性和准确性。对不同CT图像重建方法的这些结果进行比较。
在28例共448个节段的患者中，LGE-MRI诊断为阳性的节段有160个。在心肌CT-LE的定性评估中，HIR的平均图像质量评分为2.9±1.2，MBIR_cardiac为3.0±1.1，MBIR_myo为4.0±1.0。MBIR_myo的评分显著高于HIR（P<0.001）和MBIR_cardiac（P = 0.018）。在心肌CT-LE的定量图像质量评估中，HIR的图像SNR中位数为10.3（9.1 - 11.1），MBIR_cardiac为10.8（9.8 - 12.1），MBIR_myo为16.8（15.7 - 18.4）。HIR的图像CNR中位数为3.7（3.0 - 4.6），MBIR_cardiac为3.8（3.2 - 5.1），MBIR_myo为6.4（5.0 - 7.7）。与HIR和MBIR_cardiac相比，MBIR_myo显著提高了CT-LE的SNR和CNR（P<0.001）。HIR检测心肌CT-LE的敏感性、特异性和准确性分别为70%、92%和84%；MBIR_cardiac为71%、92%和85%；MBIR_myo为84%、92%和89%。MBIR_myo的图像质量、敏感性和准确性显著高于其他方法（P<0.05）。
针对心肌调整的MBIR提高了心肌CT-LE评估的图像质量和诊断性能。
