Department of Radiology, Chiba University Hospital, 1-8-1, Inohana, Chuo-ku, Chiba City, Chiba, 260-8677, Japan.
Department of Radiology, Chiba University Hospital, 1-8-1, Inohana, Chuo-ku, Chiba City, Chiba, 260-8677, Japan.
Eur J Radiol. 2019 Feb;111:56-61. doi: 10.1016/j.ejrad.2018.12.014. Epub 2018 Dec 14.
Preoperative identification of Adamkiewicz artery (AKA) for preventing postoperative spinal cord ischemia is still challenging because of its small diameter. Low-tube-voltage technique might improve the delineation of AKA due to its higher contrast enhancement and contrast-to-noise ratio (CNR). Our purpose was to evaluate the usefulness of low-tube-voltage CTA in visualization of AKA compared with the conventional voltage protocol on the condition with the same imaging parameters aside from tube voltage.
Eighty-three patients undergoing CTA for the evaluation of aorta were retrospectively included. All CTA was performed with 320-detector-row CT with the tube voltage of either 100-kVp (41 patients) or 120-kVp (42 patients). The CNR, CT value of aorta and objective image noise were assessed. Visualization of AKA was evaluated based on the continuity from aorta using the four-grade score by two independent reviewers. The estimated radiation dose (volumetric CT dose index) was also compared.
The 100-kVp group showed significantly higher CNR and CT value than 120-kVp protocol (P = 0.010 and < 0.001, respectively). The visual score was also significantly higher in 100-kVp group than in 120-kVp group (2.73 ± 0.98 and 2.02 ± 1.00, respectively; P = 0.002). There was no significant difference on objective image noise and radiation dose between the groups (P = 0.24 and 0.72, respectively).
CTA with low-tube-voltage was significantly more sensitive for AKA visualization than conventional voltage protocol.
由于 Adamkiewicz 动脉（AKA）直径较小，因此术前对其进行识别以预防术后脊髓缺血仍然具有挑战性。低管电压技术可以通过提高对比度增强和对比噪声比（CNR）来改善 AKA 的描绘。我们的目的是评估低管电压 CTA 在与常规电压方案相同的成像参数条件下，在管电压不同的情况下，对 AKA 的可视化的有用性。
回顾性纳入 83 例因主动脉评估而行 CTA 的患者。所有 CTA 均使用 320 排探测器 CT 进行，管电压分别为 100 kVp（41 例）或 120 kVp（42 例）。评估 CNR、主动脉 CT 值和客观图像噪声。根据从主动脉连续的四级评分由两位独立的审阅者评估 AKA 的可视化。还比较了估计的辐射剂量（容积 CT 剂量指数）。
100 kVp 组的 CNR 和 CT 值明显高于 120 kVp 方案（P=0.010 和 <0.001）。100 kVp 组的视觉评分也明显高于 120 kVp 组（2.73±0.98 和 2.02±1.00，分别；P=0.002）。两组之间的客观图像噪声和辐射剂量无显著差异（P=0.24 和 0.72）。
与常规电压方案相比，低管电压 CTA 对 AKA 的可视化更敏感。
