Computed Tomography Angiography (CTA)
CT angiography has been an imaging technique since the 1990s that uses ionized radiation in combination with an intravenous contrast agent to produce high-resolution images of the human vascular system. [54] Modern CT scanners can generate high-resolution three-dimensional (3D) datasets with excellent spatial and temporal resolution in a single breath-hold during the first pass of intravenous contrast injection. CTA protocols typically include three phases: non-contrast, arterial phase, and delayed phase, each tailored to specific clinical scenarios. The timing of image acquisition relative to contrast injection is crucial for optimal contrast opacification. Post-processing techniques, such as multiplanar reconstruction (MPR) and maximum intensity projection (MIP), allow for detailed visualization and assessment of vascular anatomy. Additionally, curved planar reformats (CPR) and bone removal techniques enhance visualization, particularly in cases of tortuous anatomy. Advanced methods, such as dual-energy CT (DECT), offer improved differentiation between iodine and bone, further enhancing image quality and diagnostic accuracy. [66] CT-Angiography has several advantages that set it apart from precursor techniques such as Doppler. In comparison, these include higher accuracy, shorter examination times and the visualization of smaller-lumen vessels, including intramuscular vessel courses and the course of perforator vessels. [5, 6]