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]