In Vitro Modeling of Human Brain Arteriovenous Malformation for Endovascular Simulation and Flow Analysis.

ABSTRACT BACKGROUND Current in vitro models for human brain arteriovenous malformation (AVM) analyzing the efficacy of embolic materials or flow conditions are limited by a lack of realistic anatomic features of complex AVM nidus. The purpose of this study is to evaluate a newly developed in vitro AVM model for embolic material testing, preclinical training and flow analysis. METHODS 3D images of the AVM nidus were extracted from 3D rotational angiography from a patient. Inner vascular mold was printed using a 3D printer, coated with polydimethylsiloxanes, and then was removed by acetone, leaving a hollow AVM model. Injections of liquid embolic material and 4D flow MRI were performed using the AVM models. Besides, computational fluid dynamics (CFD) analysis was performed to examine the flow volume rate as compared to 4D flow MRI. RESULTS The manufacture of 3D in vitro AVM models delivers a realistic representation of human nidus vasculature and complexity derived from patients. The injection of liquid embolic agents performed in the in vitro model successfully replicated real-life treatment conditions. The model simulated the plug and push technique before penetration of the liquid embolic material into the AVM nidus. 4D flow MRI results were comparable to CFD analysis. CONCLUSIONS An in vitro human brain AVM model with realistic geometrical complexities of nidus was successfully created using 3D printing technology. This AVM model offers a useful tool for training of embolization techniques and analysis of hemodynamics analysis, and development of new devices and materials.