PDF(Pubmed)
Abstract：
UNASSIGNED: Spatio-temporal variability in clinical fluoroscopy and cine angiography images combined with nonlinear image processing prevents the application of traditional image quality measurements in the cardiac catheterization laboratory. We aimed to develop and validate methods to measure human observer impressions of the image quality.
UNASSIGNED: Multi-frame images of the thorax of a euthanized pig were acquired to provide an anatomical background. The detector dose was varied from 6 to 200 nGy (increments 2×), and 0.6 and 1.0 mm focal spots were used. Two coronary stents with/without 0.5 mm separation and a synthetic right coronary artery (RCA) with hemispherical defects were embedded into the background images as test objects. The quantitative observer ( n = 17 ) performance was measured using a two-alternating forced-choice test of whether stents were separated and by a count of visible right coronary artery defects. Qualitative impressions of noise, spatial resolution, and overall image quality were measured using a visual analog scale (VAS). A paired t -test and multinomial logistic regression model were used to identify statistically significant factors affecting the observer\'s impression image quality.
UNASSIGNED: The proportion of correct detection of stent separation and the number of reported right coronary artery defects changed significantly with detector dose increment in the 6 to 100 nGy ( p < 0.05 ). Although a trend favored the 0.6 versus 1.0 mm focal spot for these quantitative assessments, this was insignificant. Visual analog scale measurements changed significantly with detector dose increments in the range of 24 to 100 nGy and focal spot size ( p < 0.05 ). The application of multinomial logistic regression analysis to observer VAS scores demonstrated sensitivity matching of the paired t -test applied to quantitative observer performance measurements.
UNASSIGNED: Both quantitative and qualitative measurements of observer impression of the image quality were sensitive to image quality changes associated with changing the detector dose and focal spot size. These findings encourage future work that uses qualitative image quality measurements to assess clinical fluoroscopy and angiography image quality.
UNASSIGNED: Multi-frame images of the thorax of a euthanized pig were acquired to provide an anatomical background. The detector dose was varied from 6 to 200 nGy (increments 2×), and 0.6 and 1.0 mm focal spots were used. Two coronary stents with/without 0.5 mm separation and a synthetic right coronary artery (RCA) with hemispherical defects were embedded into the background images as test objects. The quantitative observer ( n = 17 ) performance was measured using a two-alternating forced-choice test of whether stents were separated and by a count of visible right coronary artery defects. Qualitative impressions of noise, spatial resolution, and overall image quality were measured using a visual analog scale (VAS). A paired t -test and multinomial logistic regression model were used to identify statistically significant factors affecting the observer\'s impression image quality.
UNASSIGNED: The proportion of correct detection of stent separation and the number of reported right coronary artery defects changed significantly with detector dose increment in the 6 to 100 nGy ( p < 0.05 ). Although a trend favored the 0.6 versus 1.0 mm focal spot for these quantitative assessments, this was insignificant. Visual analog scale measurements changed significantly with detector dose increments in the range of 24 to 100 nGy and focal spot size ( p < 0.05 ). The application of multinomial logistic regression analysis to observer VAS scores demonstrated sensitivity matching of the paired t -test applied to quantitative observer performance measurements.
UNASSIGNED: Both quantitative and qualitative measurements of observer impression of the image quality were sensitive to image quality changes associated with changing the detector dose and focal spot size. These findings encourage future work that uses qualitative image quality measurements to assess clinical fluoroscopy and angiography image quality.
摘要：
■临床透视和电影血管造影图像中的时空变异性与非线性图像处理相结合，阻止了传统图像质量测量在心导管实验室中的应用。我们旨在开发和验证方法来测量人类观察者对图像质量的印象。
■获取安乐死猪的胸部的多帧图像以提供解剖背景。检测器剂量从6到200nGy(增量2倍)变化，并且使用0.6和1.0mm的焦斑。将两个具有/不具有0.5mm间隔的冠状动脉支架和具有半球形缺损的合成右冠状动脉（RCA）嵌入背景图像中作为测试对象。定量观察者（n=17）的表现是使用两次交替的强制选择测试来测量支架是否分离以及可见的右冠状动脉缺陷的计数。对噪音的定性印象，空间分辨率,使用视觉模拟量表（VAS）测量整体图像质量。使用配对t检验和多项logistic回归模型来确定影响观察者印象图像质量的有统计学意义的因素。
■正确检测支架分离的比例和报告的右冠状动脉缺陷的数量随着检测器剂量在6至100nGy中的增加而显着变化（p<0.05）。尽管对于这些定量评估，趋势倾向于0.6毫米与1.0毫米的焦点，这是微不足道的。随着检测器剂量增量在24至100nGy范围内和焦斑尺寸(p<0.05),视觉模拟量标测量值显著变化。将多项逻辑回归分析应用于观察者VAS评分，证明了应用于定量观察者绩效测量的配对t检验的敏感性匹配。
■观察者对图像质量的印象的定量和定性测量都对与改变检测器剂量和焦斑大小相关的图像质量变化敏感。这些发现鼓励使用定性图像质量测量来评估临床透视和血管造影图像质量的未来工作。
■获取安乐死猪的胸部的多帧图像以提供解剖背景。检测器剂量从6到200nGy(增量2倍)变化，并且使用0.6和1.0mm的焦斑。将两个具有/不具有0.5mm间隔的冠状动脉支架和具有半球形缺损的合成右冠状动脉（RCA）嵌入背景图像中作为测试对象。定量观察者（n=17）的表现是使用两次交替的强制选择测试来测量支架是否分离以及可见的右冠状动脉缺陷的计数。对噪音的定性印象，空间分辨率,使用视觉模拟量表（VAS）测量整体图像质量。使用配对t检验和多项logistic回归模型来确定影响观察者印象图像质量的有统计学意义的因素。
■正确检测支架分离的比例和报告的右冠状动脉缺陷的数量随着检测器剂量在6至100nGy中的增加而显着变化（p<0.05）。尽管对于这些定量评估，趋势倾向于0.6毫米与1.0毫米的焦点，这是微不足道的。随着检测器剂量增量在24至100nGy范围内和焦斑尺寸(p<0.05),视觉模拟量标测量值显著变化。将多项逻辑回归分析应用于观察者VAS评分，证明了应用于定量观察者绩效测量的配对t检验的敏感性匹配。
■观察者对图像质量的印象的定量和定性测量都对与改变检测器剂量和焦斑大小相关的图像质量变化敏感。这些发现鼓励使用定性图像质量测量来评估临床透视和血管造影图像质量的未来工作。
