While angiography may be considered the gold standard for evaluating diseases of the human vasculature, vascular flow details are unavailable due to the low temporal resolution of flat panel detectors (FPDs) which operate at a maximum of 15 – 30 fps. Higher frame rates are necessary to extract any meaningful flow detail, which may act as additional information that can be used to characterize flow-dependent disease states. These higher rates have become available with recent advances in photon-counting detector (PCD) technology. The XCounter Actaeon was used to perform high frame rate imaging at 1000 fps. The Actaeon also provides superior spatial resolution due to its 100 um pixel size and electronic charge sharing correction, making it a good candidate for small ROI imaging. With this detector, “High Speed Angiography” (HSA) was performed on a variety of 3D printed patient-specific vasculature and interventional devices, using a simulated flow loop and iodinated contrast media. The images, which illustrate pathology-dependent flow detail, were recorded in a sequence of 1 ms frames. In addition, the energy discrimination capabilities of the Actaeon were used such that with a lower energy threshold, instrumentation noise was virtually negligible. The per frame noise quality and overall patient dose were acceptable as compared to standard angiography dose rates using FPDs. The previously unseen flow detail may give new insight into the diagnosis, progression, and treatment of neuro and cardiovascular pathologies.
|