In vitro models of intracranial arteriovenous fistulas for the evaluation of new endovascular treatment materials

BACKGROUND AND PURPOSE: The purpose of this study was to create and test an in vitro model of intracranial arteriovenous fistulas (AVFs) that simulate s the geometry of human vasculature and allows realistic testing of devices used in endovascular therapy. METHODS: The models were derived from corrosion casts of the main cervicocr anial arteries and veins obtained from two nonfixed human specimens. Wax co pies of the casts were produced and combined to create complex models simul ating various types of intracranial AVFs, Wax assemblies were embedded with liquid silicone solidified into transparent blocks containing, after wax e vacuation, hollow reproductions of the original vascular trees. The models were connected to a pulsatile pump and their compatibility with various ima ging techniques and endovascular treatment materials was evaluated. RESULTS: The models were compatible with digital subtraction angiography, C T, MR imaging, and transcranial Doppler sonography. They provided a realist ic endovascular environment for the simulation of interventional neuroradio logic procedures. CONCLUSION: Anatomically accurate and reproducible in vitro models of intra cranial AVFs provide a valuable method for evaluating new endovascular trea tment materials and for teaching purposes.