Pressure Measurements during Embolization of an AVM

Abstract

The endoscopic embolization of arterio venous malformations in the brain is a technique that potentiates the risk of rupture of the blood vessels and a subsequent cerebral haemorrhage. Knowledge of cerebral hemodynamics in its various aspects is fundamental to control and have a better understanding of the therapeutical risks associated with embolizations.

We obtained pressure measurements, through microcatheters, during an interventional in vivo embolization, and analyzed them as a way of studying the local hemodynamic changes caused by embolization.

However, the use of microcatheters to measure endovascular pressures presents some difficulties since the measurement of pressure is not independent of factors like, for example, the internal distal diameter of the microcatheter. With that in mind a study of the pressure responses of the various microcatheters with different distal diameters was performed. From this study tables with correction factors to apply to the measurements acquired by the different microcatheters as a function of pressure were obtained, allowing the analysis of the pressure measurements acquired during the in vivo embolization. Thus, during the in vivo embolization it was possible to observe that the mean pressure in the feeding arteries of the arterio venous malformation increased in the minutes following the embolization, corresponding to an increase in the risk of rupture of the blood vessels.