Radioembolization (RE) is a valuable treatment for liver cancer. It consists of administering
radioactive microspheres by an intra-arterially placed catheter with the aim of
lodging these microspheres, which are driven by the bloodstream, in the tumoral bed. Even
though it is a safe treatment, some radiation-induced complications may arise. In trying to
detect or solve the possible incidences that cause nontarget irradiation, simulating the particle-
hemodynamics in hepatic arteries during RE by computational fluid dynamics (CFD)
tools has become a valuable approach. This paper reviews the parameters that influence the
outcome of RE and that have been studied via numerical simulations. In this numerical approach,
the outcome of RE is regarded as successful if particles reach the artery branches that
feed tumor-bearing liver segments. Up to 10 parameters have been reviewed. The variation
of each parameter actually alters the hemodynamic pattern in the vicinities of the catheter tip
and locally alters the incorporation of the particles into the bloodstream. Therefore, in general,
the local influences of these parameters should result in global differences in terms of
particle distribution in the hepatic artery branches. However, it has been observed that under
some (qualitatively described) appropriate conditions where particles align with blood
streamlines, the local influence resulting from a variation of a given parameter vanishes and
no global differences are observed. Furthermore, the increasing number of CFD studies on
RE suggests that numerical simulations have become an invaluable research tool in the study
of RE.
