PMC5412625_01
Overview of post-processing of cardiac computed tomography angiography (CTA) from the scanning console. A: Scanned range covering the entire heart, at 300 msec time-point at the level of the yellow line in the scout radiography, shows motion artifact in the proximal right coronary artery (arrow). B: Scanned range covering upper portion of the heart, at 240 msec time-point now demonstrates an aneurysmal right coronary artery without motion artifact (arrow). C: Scanned range covering the bottom half of the heart, at 360 msec time-point shows a partially calcified moderate stenosis in the mid right coronary artery (arrow). a: Scout radiographs showing the scanned range (pink box) with the yellow line representing the time-point of the scan. b: Rhythm strip demonstrates premature ventricular contractions (PVCs) every third beat of the cardiac cycle (trigeminy). Heart rate in beats per minute (bpm) was an average of 58, ranging from 68 to 109. Note the CTA is acquired as a systolic-targeted prospective ECG-triggered scan with a data acquisition window between 200 and 450 msec following each R peak (dark and light purple boxes on the rhythm strip). Despite application of an advanced arrhythmia rejection algorithm ("Adaptive Cardio Seq."), the ectopic beats have not been excluded from acquisition (green arrows mark the post-PVC acquisitions). c: Resultant computed tomography image.
gr1.jpg
PMC5412625_01_gr1.jpg
f0005
From the single-acquisition dataset as shown in Figure 1A, the disparate artifact-free phase intervals were reconstructed separately for proximal (240 ms time point) and distal (360 ms time point) coronary artery segments as shown in Figure 1B and Figure 1C, respectively.
A: Outline of the definitive steps for image processing. B: Cardiac 3-dimensional (3-D) planes from the combined phase's series. a: Axial section; b: 3-D rendering. Notice the easily recognizable slab-to-slab misalignment artifact on the coronal (c) and sagittal (d) views of the heart (arrows) resulting from combining images from the 240 ms phase reconstruction (top half) and 360 ms phase reconstruction (bottom half). The 3-D volume-rendered reconstruction of the heart in the bottom right corner also shows easily recognizable slab-to-slab misalignment artifact and 2 serial aneurysms of the proximal right coronary artery (arrowheads).
gr2.jpg
PMC5412625_01_gr2.jpg
f0010
Using otherwise identical parameters, these 2 datasets, each with a 0.75 mm image slice thickness and a 0.4 mm slice interval, were then combined in parallel range to reconstruct a unique dataset as illustrated in a flow chart in Figure 2A. The resultant image had diagnostic quality in all coronary segments, despite an easily recognizable slab-to-slab misalignment artifact, as shown in Figure 2B at the merge plane (ie, the end position of the proximal dataset and beginning position of the distal dataset).
Representative images of the curved planar reformatted diagnostic cardiac computed tomography angiography (CTA) dataset derived from the combined phase series in concordance with invasive coronary angiography (ICA) findings. A: Right coronary artery (RCA); arrowheads show aneurysms. B: Left anterior descending artery (LAD). C: Left circumflex artery. Arrows denote slab-to-slab misalignment artifacts. Cardiac CTA findings completely correlated to that of ICA, demonstrating coronary atherosclerosis with multiple aneurysms and multisegment moderate stenosis in the RCA and LAD.
gr3.jpg
PMC5412625_01_gr3.jpg
f0015
CCTA demonstrated coronary atherosclerotic disease with multiple aneurysms and multisegment moderate stenosis in the right coronary artery and left anterior descending artery with excellent correlation with invasive coronary angiography, as shown in Figure 3.