Mühlenbruch G, Wildberger J E, Koos R, Das M, Thomas C, Ruhl K, Niethammer M, Floh T G, Stanzel S, Günther R W, Mahnken A H
Department of Diagnostic Radiology, Department of Cardiology, Institute of Medical Statistics, University Hospital (RWTH) Aachen, Germany.
Acta Radiol. 2005 Oct;46(6):561-6. doi: 10.1080/02841850510021698.
Previous studies have shown a positive correlation between amount of aortic valve calcification (AVC) and degree of aortic valve stenosis (AVS). We have investigated whether calcium scoring of AVC from contrast-enhanced images is reliable.
Nineteen patients with suspected AVS underwent retrospectively ECG-gated multislice computed tomography (MSCT). Standardized scan protocols were applied prior to (120 KV, 133 mAseff) and after (120 KV, 500 mAseff) the administration of non-ionic contrast material. Image reconstruction was performed at 60% of the RR interval (slice thickness 3 mm, reconstruction increment 2 mm). AVC was quantified using Agatston score and calcium mass. The number of lesions was calculated. All nonenhanced images were scored using thresholds of 130 HU and 350 HU. Contrast-enhanced images were assessed with a threshold of 350 HU exclusively.
Fifteen patients with AVCs were included in the statistical analysis. The mean Agatston score (calcium mass) in non-enhanced images was 2888.4 +/- 2844.4 (694.2 mg +/- 869.3 mg). Altering the threshold from 130 HU to 350 HU led to a 58.2% (30.5%) decrease in the AVC score (P values < 0.001). Contrast-enhanced images showed an increased Agatston score (calcium mass) of 56.2% (33.5%) compared to non-enhanced images (P values <0.05) with the same threshold of 350 HU.
Quantification of AVC from contrast-enhanced images is not reliable, as contrast material simulates calcification.
先前的研究表明主动脉瓣钙化（AVC）量与主动脉瓣狭窄（AVS）程度之间存在正相关。我们研究了从增强图像中对AVC进行钙化评分是否可靠。
19例疑似AVS患者接受回顾性心电图门控多层螺旋计算机断层扫描（MSCT）。在注射非离子型对比剂之前（120 kV，133 mAs有效剂量）和之后（120 kV，500 mAs有效剂量）应用标准化扫描方案。在RR间期的60%进行图像重建（层厚3 mm，重建间隔2 mm）。使用阿加斯顿评分和钙质量对AVC进行量化。计算病变数量。所有未增强图像使用130 HU和350 HU的阈值进行评分。增强图像仅使用350 HU的阈值进行评估。
15例有AVC的患者纳入统计分析。未增强图像中的平均阿加斯顿评分（钙质量）为2888.4±2844.4（694.2 mg±869.3 mg）。将阈值从130 HU改为350 HU导致AVC评分降低58.2%（30.5%）（P值<0.001）。在350 HU的相同阈值下，增强图像显示阿加斯顿评分（钙质量）比未增强图像增加了56.2%（33.5%）（P值<0.05）。
由于对比剂模拟钙化，从增强图像中对AVC进行量化不可靠。
