Department of Radiology, University Hospital Leuven, Herestraat, 49, 3000 - Leuven, Louvain, Belgium.
Medical Imaging Research Center, Medical Physics and Quality Assessment, Katholieke Universiteit Leuven, 3000 - Leuven, Louvain, Belgium.
Eur Radiol. 2018 Jul;28(7):2951-2959. doi: 10.1007/s00330-017-5301-2. Epub 2018 Feb 19.
To evaluate the impact of digital detector, dose level and post-processing on neonatal chest phantom X-ray image quality (IQ).
A neonatal phantom was imaged using four different detectors: a CR powder phosphor (PIP), a CR needle phosphor (NIP) and two wireless CsI DR detectors (DXD and DRX). Five different dose levels were studied for each detector and two post-processing algorithms evaluated for each vendor. Three paediatric radiologists scored the images using European quality criteria plus additional questions on vascular lines, noise and disease simulation. Visual grading characteristics and ordinal regression statistics were used to evaluate the effect of detector type, post-processing and dose on VGA score (VGAS).
No significant differences were found between the NIP, DXD and CRX detectors (p>0.05) whereas the PIP detector had significantly lower VGAS (p< 0.0001). Processing did not influence VGAS (p=0.819). Increasing dose resulted in significantly higher VGAS (p<0.0001). Visual grading analysis (VGA) identified a detector air kerma/image (DAK/image) of ~2.4 μGy as an ideal working point for NIP, DXD and DRX detectors.
VGAS tracked IQ differences between detectors and dose levels but not image post-processing changes. VGA showed a DAK/image value above which perceived IQ did not improve, potentially useful for commissioning.
• A VGA study detects IQ differences between detectors and dose levels. • The NIP detector matched the VGAS of the CsI DR detectors. • VGA data are useful in setting initial detector air kerma level. • Differences in NNPS were consistent with changes in VGAS.
评估数字探测器、剂量水平和后处理对新生儿胸部体模 X 射线图像质量（IQ）的影响。
使用四种不同的探测器对新生儿体模进行成像：CR 粉末磷光体（PIP）、CR 针状磷光体（NIP）和两个无线 CsI DR 探测器（DXD 和 DRX）。针对每种探测器研究了五个不同的剂量水平，并针对每个供应商评估了两种后处理算法。三位儿科放射科医生使用欧洲质量标准以及血管线、噪声和疾病模拟的附加问题对图像进行评分。使用视觉分级特征和有序回归统计来评估探测器类型、后处理和剂量对 VGA 评分（VGAS）的影响。
NIP、DXD 和 CRX 探测器之间没有发现显著差异（p>0.05），而 PIP 探测器的 VGAS 明显较低（p<0.0001）。处理不影响 VGAS（p=0.819）。剂量增加导致 VGAS 显著提高（p<0.0001）。视觉分级分析（VGA）确定 NIP、DXD 和 DRX 探测器的理想工作点为探测器空气比释动能/图像（DAK/image）约为 2.4 μGy。
VGAS 跟踪了探测器和剂量水平之间的 IQ 差异，但没有跟踪图像后处理变化。VGA 显示出一个 DAK/image 值，超过该值，感知的 IQ 不会提高，这对于委托工作可能很有用。
VGA 研究检测到探测器和剂量水平之间的 IQ 差异。
NIP 探测器与 CsI DR 探测器的 VGAS 匹配。
VGA 数据有助于设置初始探测器空气比释动能水平。
NNPS 的差异与 VGAS 的变化一致。
