Coudyzer Walter, Cockmartin Lesley, Miseur Bram, Busselot Tim, Bielen Didier, Vanbeckevoort Dirk, Oyen Raymond, Bosmans Hilde
Department of Radiology, University Hospitals KU Leuven, Herestraat 49, 3000 Leuven, Belgium.
J Belg Soc Radiol. 2025 Jun 9;109(1):21. doi: 10.5334/jbsr.3906. eCollection 2025.
to determine (1) a target Hounsfield unit (HU) for portal venous phase iodinated contrast media enhanced abdominal CT scans, (2) an equation for a personalized total contrast agent volume, and (3) the best/most appropriate time between injection and plateau/peak in HU enhancement. from an original dataset of 5,000 cases, a weight representative subset of 370 cases was sampled for detailed HU measurements. An additional 90 cases were used for visual grading to define the minimal HU required for diagnostic quality, which led to the proposed target HU. This study uses the fact that in a first approach, the injected contrast agent volume and HU correlate linearly. Based on the injected contrast agent volumes and HU measurements in the patient scans, it was then calculated which (ideal) volume would have reached the target value. The ideal volumes and patient data (weight, height, heart rate, age, and gender) were correlated by means of a regression analysis, to determine a new patient-specific contrast volume calculation equation. The best scan delay time was derived from the start of the injection to the HU enhancement plateau/peak evaluated from manually triggered venous phase scans. The target HU value was 125. This can be achieved with a personalized contrast agent volume (ml), equal to - 108.5 + ∗ + 0.40 ∗ + 0.61 ∗ . The time delay between injection and HU plateau/peak was found to be, on average, 102 s. this study proposes a comprehensive protocol for contrast enhanced venous phase scans, including a target HU, a personalized contrast volume, and a scan delay.
(1) 门静脉期碘对比剂增强腹部CT扫描的目标亨氏单位（HU）；(2) 个性化总对比剂体积的计算公式；(3) 注射对比剂至HU增强达到平台期/峰值之间的最佳/最合适时间。从5000例的原始数据集中，抽取了370例具有代表性的样本进行详细的HU测量。另外90例用于视觉分级，以确定诊断质量所需的最小HU，从而得出建议的目标HU。本研究利用了这样一个事实，即在第一种方法中，注射的对比剂体积与HU呈线性相关。根据患者扫描中的注射对比剂体积和HU测量值，计算出达到目标值所需的（理想）体积。通过回归分析将理想体积与患者数据（体重、身高、心率、年龄和性别）进行关联，以确定新的患者特异性对比剂体积计算公式。最佳扫描延迟时间是从注射开始到通过手动触发的静脉期扫描评估的HU增强平台期/峰值的时间。目标HU值为125。这可以通过个性化对比剂体积（毫升）来实现，其计算公式为 - 108.5 + ∗ + 0.40 ∗ + 0.61 ∗ 。发现注射与HU平台期/峰值之间的平均时间延迟为102秒。本研究提出了一种用于对比剂增强静脉期扫描的综合方案，包括目标HU、个性化对比剂体积和扫描延迟。
