The role of angled‐tip microcatheter and microsphere injection velocity in liver radioembolization: A computational particle–hemodynamics study

Abstract

Liver radioembolization is a promising treatment option for combating liver tumors. It is performed by placing a microcatheter in the hepatic artery and administering radiation-emitting microspheres through the arterial bloodstream so that they get lodged in the tumoral bed. In avoiding nontarget radiation, the standard practice is to conduct a pretreatment, in which the microcatheter location and injection velocity are decided. However, between pretreatment and actual treatment, some of the parameters that influence the particle distribution in the liver can vary, resulting in radiation-induced complications. The present study aims to analyze the influence of a commercially available microcatheter with an angled tip and particle injection velocity in terms of segment-to-segment particle distribution. Specifically, 4 tip orientations and 2 injection velocities are combined to yield a set of 8 numerical simulations of the particle-hemodynamics in a patient-specific truncated hepatic artery. For each simulation, 4 cardiac pulses are simulated. Particles are injected during the first cycle, and the remaining pulses enable the majority of the injected particles to exit the computational domain. Results indicate that, in terms of injection velocity, particles are more spread out in the cross-sectional lumen areas as the injection velocity increases. The tip's orientation also plays a role because it influences the near-tip hemodynamics, therefore altering the particle travel through the hepatic artery. However, results suggest that particle distribution tries to match the blood flow split, therefore particle injection velocity and microcatheter tip orientation playing a minor role in segment-to-segment particle distribution.

Realistic boundary conditions in SimVascular through inlet catheter modeling

“…Catheters are commonly used in medical procedures in a wide range of applications from drug delivery such as in tumor embolization to dialysis, injection of intravenous fluids, and invasive methods of measuring cardiovascular parameters. Previous studies suggest that the presence of a catheter affects the local flow field and flow distribution in downstream vessel trees [ 7 – 10 ] and therefore it might alter the hemodynamics quantities of interest [ 11 , 12 ]. For example, when a catheter is used to administer antibiotics, bland particles, chemo beads, glue (as an embolism material), parental nutrition, or other drugs in liquid form, any alterations in the flow field, even in the short period of time that the catheter is inserted into the vessels, can change the downstream blood flow and therapeutic agent distribution, and consequently affect the procedure efficiency.…”

Computational Fluid Dynamics Modeling of Liver Radioembolization: A Review

“…Blood has been assumed to have a density of 1060 kg/m 3 [ 12 , 18 , 21 – 25 , 27 , 29 – 32 ] or 1050 kg/m 3 [ 10 , 13 – 17 , 20 , 26 , 33 , 34 , 37 ]. Blood densities around 1050 kg/m 3 have been measured in the arterial level, decreasing to a value of 1040 kg/m 3 at the capillary level [ 38 ].…”

CFD Simulations of Radioembolization: A Proof-of-Concept Study on the Impact of the Hepatic Artery Tree Truncation

“…In the last decade, a number of studies have been published on the computational fluid dynamics-based (CFD) simulation of the hepatic artery hemodynamics and microsphere transport during RE [3]. Some studies have focused on the type of microcatheter (e.g., standard end-hole microcatheter, antireflux catheter, angled-tip microcatheter) [4][5][6], and others have focused on the influence of various treatment and patient parameters (e.g., injection velocity, microcatheter location, hepatic artery geometry, etc.) on the microsphere distribution [7][8][9].…”