Integration of high velocity test object motion into a channelized Hotelling observer for the assessment of x-ray angiography systems

Published on Sep 17, 2019in Physics in Medicine and Biology2.883
· DOI :10.1088/1361-6560/AB39C4
Ashley Tao (Gundersen Health System), Ashley T. Tao3
Estimated H-index: 3
(Gundersen Health System),
Kenneth A. Fetterly18
Estimated H-index: 18
Sources
Abstract
: Assessment of x-ray angiography system performance is typically performed using stationary test objects with simple geometries such as a disk on a uniform background. However, these methods do not represent realistic imaging conditions in interventional cardiology as anatomy and devices are inherently non-stationary due to cardiac motion. In this work, a novel implementation of the channelized Hotelling observer (CHO) was used to assess the influence of motion blur on object detectability. A standard CHO model assumes imaging system stationarity whereby the detectability index [Formula: see text] of a test object is independent of location. However, real angiography systems are inherently non-stationary. While vendor correction gain factors and offset maps are used to compensate for visual non-uniformities, these corrections do not restore stationarity to the images. Methods to accommodate non-stationarity and allow assessment of the influence of motion blur on test object detectability will be presented. The effect of motion blur was quantified with the relative detectability index ([Formula: see text]), where the [Formula: see text] for an object when moving with constant linear velocity was compared to a low velocity 'pseudo-stationary' condition to account for system non-stationarity. The pseudo-stationary condition was used to isolate the influences of spatial non-stationarity and motion blur. Three different test object shapes (disks, spheres and capsules) with linear velocity in the range 0-30 cm · s-1 were tested. For 1 mm diameter objects and linear velocity 30 cm · s-1, [Formula: see text] was degraded by 37%, 33% and 42% for the disk, sphere and capsule respectively, relative to the pseudo-stationary condition. Considering all test objects with diameter greater than 2 mm and linear velocity 30 cm · s-1, [Formula: see text] was degraded by less than 10% due to motion. In summary, this work describes a new approach to assess performance of x-ray angiography systems using the CHO model and moving test objects.
📖 Papers frequently viewed together
2009
1 Author (Adam Wunderlich)
References18
Newest
PURPOSE: Electronic noise associated with passive pixel (PP) x-ray angiography flat panel detectors is known to compromise fluoroscopic image quality. An active pixel (AP) crystalline silicon x-ray detector with potential for reduced influence of electronic noise is commercially available. The purpose of this work was to compare the performance of the AP vs PP x-ray angiography detectors over a detector target dose (DTD) range relevant for invasive cardiology procedures. METHODS: A total of 16 p...
1 CitationsSource
Channelized Hotelling model observer (CHO) methods were developed to assess performance of an x-ray angiography system. The analytical methods included correction for known bias error due to finite sampling. Detectability indices ([Formula: see text]) corresponding to disk-shaped objects with diameters in the range 0.5-4 mm were calculated. Application of the CHO for variable detector target dose (DTD) in the range 6-240 nGy frame(-1) resulted in [Formula: see text] estimates which were as much ...
4 CitationsSource
#1Christopher P. Favazza (Mayo Clinic)H-Index: 24
#2Kenneth A. Fetterly (Mayo Clinic)H-Index: 18
Last. Beth A. Schueler (Mayo Clinic)H-Index: 32
view all 5 authors...
Evaluation of flat-panel angiography equipment through conventional image quality metrics is limited by the scope of standard spatial-domain image quality metric(s), such as contrast-to-noise ratio and spatial resolution, or by restricted access to appropriate data to calculate Fourier domain measurements, such as modulation transfer function, noise power spectrum, and detective quantum efficiency. Observer models have been shown capable of overcoming these limitations and are able to comprehens...
10 CitationsSource
#1V Singh (UB: University at Buffalo)H-Index: 4
#2Anil K. Jain (UB: University at Buffalo)H-Index: 199
Last. Stephen Rudin (UB: University at Buffalo)H-Index: 24
view all 4 authors...
Relative object detectability (ROD) quantifies the relative performance of two image detectors for a specified object of interest by taking the following ratio: the integral of detective quantum efficiency of a detector weighted by the frequency spectrum of the object divided by that for a second detector. Four different detectors, namely the microangiographic fluoroscope (MAF), the Dexela Model 1207 (Dex) and Hamamatsu Model C10901D-40 (Ham) CMOS xray detectors, and a flat-panel detector (FPD) ...
4 CitationsSource
#1Xin He (FDA: Food and Drug Administration)H-Index: 1
#2Subok ParkH-Index: 15
Model observers play an important role in the optimization and assessment of imaging devices. In this review paper, we first discuss the basic concepts of model observers, which include the mathematical foundations and psychophysical considerations in designing both optimal observers for optimizing imaging systems and anthropomorphic observers for modeling human observers. Second, we survey a few state-of-the-art computational techniques for estimating model observers and the principles of imple...
62 CitationsSource
#1Guy Shechter (Johns Hopkins University)H-Index: 10
#2Jon R. ResarH-Index: 26
Last. Elliot R. McVeighH-Index: 83
view all 3 authors...
This paper presents measurements of three-dimensional (3-D) displacements and velocities of the coronary arteries due to the myocardial beating motion and due to breathing. Data were acquired by reconstructing the coronary arteries and their motion from biplane angiograms in 10 patients. A parametric motion model was used to separate the cardiac and breathing motion fields. The arteries move consistently toward the left, inferior, and anterior during a cardiac contraction. The displacement and v...
157 CitationsSource
#1Robert M. Gagne (CDRH: Center for Devices and Radiological Health)H-Index: 10
#2Brandon D. Gallas (CDRH: Center for Devices and Radiological Health)H-Index: 19
Last. Kyle J. Myers (CDRH: Center for Devices and Radiological Health)H-Index: 30
view all 3 authors...
The use of imaging phantoms is a common method of evaluating image quality in the clinical setting. These evaluations rely on a subjective decision by a human observer with respect to the faintest detectable signal(s) in the image. Because of the variable and subjective nature of the human-observer scores, the evaluations manifest a lack of precision and a potential for bias. The advent of digital imaging systems with their inherent digital data provides the opportunity to use techniques that do...
62 CitationsSource
#1Brandon D. Gallas (CDRH: Center for Devices and Radiological Health)H-Index: 19
#2Harrison H. Barrett (UA: University of Arizona)H-Index: 64
Image quality can be objectively defined according to how well an observer can perform a task of practical interest given the image. We review a practical model observer for the signal-detection task. The ideal observer for this task is a function of the image probability distributions, which are multidimensional and complicated. This observer is often too difficult to derive or estimate. An alternative to the ideal observer is the ideal linear observer, which can still be unmanageable. Our alte...
185 CitationsSource
#1Yogesh Srinivas (Case Western Reserve University)H-Index: 3
#2David L. Wilson (Case Western Reserve University)H-Index: 51
Last. David Lynn Wilson (Case Western Reserve University)H-Index: 8
view all 2 authors...
Interventional devices used in radiology often have dimensions on the order of a pixel, and radiologists resort to image magnification to better visualize such small devices. Traditional image intensifier (II) systems use analog magnification with x-ray exposure inversely proportional to the area of field of view (FOV) so as to maintain light output for the camera. Analog magnification is impossible with flat panel (FP) detectors, and images must be magnified using digital interpolation that doe...
27 CitationsSource
#1Heang Ping Chan (UM: University of Michigan)H-Index: 74
#2Berkman Sahiner (UM: University of Michigan)H-Index: 58
Last. Nicholas Petrick (UM: University of Michigan)H-Index: 43
view all 4 authors...
Classifier design is one of the key steps in the development of computer-aided diagnosis(CAD) algorithms. A classifier is designed with case samples drawn from the patient population. Generally, the sample size available for classifier design is limited, which introduces variance and bias into the performance of the trained classifier, relative to that obtained with an infinite sample size. For CAD applications, a commonly used performance index for a classifier is the area, A z , under the rece...
117 CitationsSource
Cited By0
Newest