Department of Clinical Radiology, University Hospital-Grosshadern, Ludwig-Maximilians University, Munich, Munich, Germany.
Eur Radiol. 2010 Dec;20(12):2876-81. doi: 10.1007/s00330-010-1861-0. Epub 2010 Jun 30.
The aim of this study was to test the feasibility of time-resolved computed tomography angiography (TR-CTA) for use in the lower leg.
Fifty-nine patients with suspected peripheral arterial occlusive disease were examined with a standard CTA (S-CTA) of the lower run-off and with an additional TR-CTA of the calves (12 phases; 2.5 s/phase, 80 kV, 120 mAs, volume of contrast medium 50 mL, flow rate 5.0 mL/s). For seven lower-leg artery segments, arterial contrast and the presence of venous overlay were tested for S-CTA and TR-CTA. Stenoses were classified on a three-point scale separately for S-CTA and TR-CTA, and diagnostic confidence for stenosis assessment was evaluated for both datasets. Contrast arrival times and HU values were evaluated in patients with asymmetric proximal stenoses.
TR-CTA resulted in significantly higher contrast enhancement (P < 0.0001) and less venous overlay as compared to S-CTA (P < 0.05). Diagnostic confidence for stenosis rating was significantly higher in TR-CTA (P < 0.0001). Asymmetric proximal stenoses lead to significantly delayed and diminished contrast enhancement on the stenotic side.
TR-CTA of the calves is feasible and provides higher enhancement and higher diagnostic confidence as compared to monophasic CTA of the lower legs.
本研究旨在测试时间分辨 CT 血管造影(TR-CTA)在小腿中的应用的可行性。
对 59 例疑似外周动脉闭塞性疾病的患者进行标准 CTA(S-CTA)下肢流出道检查,并进行小腿额外的 TR-CTA 检查(12 期;2.5 s/期,80 kV,120 mAs,对比剂体积 50 mL,流速 5.0 mL/s)。对 7 个小腿动脉节段,测试 S-CTA 和 TR-CTA 的动脉对比度和静脉重叠情况。分别对 S-CTA 和 TR-CTA 进行狭窄程度的三分制分级,并对两种数据集的狭窄评估诊断置信度进行评估。对近端不对称狭窄的患者评估对比剂到达时间和 HU 值。
TR-CTA 与 S-CTA 相比,对比度增强明显更高(P < 0.0001),静脉重叠明显减少(P < 0.05)。TR-CTA 的狭窄评分诊断置信度明显更高(P < 0.0001)。不对称的近端狭窄导致狭窄侧的对比度增强明显延迟和减弱。
与单期小腿 CTA 相比,小腿 TR-CTA 是可行的,可提供更高的增强和更高的诊断置信度。