Feasibility of the superselective test with propofol for determining eloquent brain regions in the endovascular treatment of arteriovenous malformations.

The superselective test for determining eloquent brain areas, carried out prior to the embolization treatment for arteriovenous malformations (AVMs), is a tool contributing to increase the safety of endovascular procedures. Taking into account amobarbital unavailability, it was decided to carry out the present study to demonstrate the efficacy and safety of propofol as an alternative to amobarbital to perform this test. A group of 58 patients were treated in 91 embolization sessions for brain AVMs using endovascular surgery between February 2006 and February 2011. The superselective test was performed prior to embolization with Histoacryl, using the intra-arterial administration of 20 mg propofol through a microcatheter positioned near the AVM nidus. Ten (7.8%) of the 128 superselective tests were positive. Neurological deficits appeared immediately after propofol administration, lasted for one minute and disappeared after five minutes. Only one of the patients showing a negative test result developed neurological deficits after embolization, for 99.2% negative predictive vale. Despite their positive test results, six patients were embolized and five developed post-embolization neurological deficits, for 83.3% positive predictive value. The test showed 83.3% sensitivity and 99.2% specificity. The use of propofol to perform the superselective test during brain AVM embolization is a safe and effective alternative to amobarbital, and may predict the occurrence of post-embolization ischemic complications.

[Endovascular treatment of intracranial arteriovenous malformation with n-butyl cyanoacrylate. Working methods and experience in 58 cases]. / Tratamiento endovascular de malformaciones arteriovenosas intracerebrales con n-butil cianoacrilato. Métodos de trabajo y experiencia en 58 casos.

BACKGROUND AND PURPOSE: Arteriovenous malformations (AVMs) constitute malformative lesions of the central nervous system vasculature and cause significant morbidity and mortality. Endovascular embolization with n-butyl cyanoacrylate is a well established modality of AVM treatment, usually combined with surgery or radiosurgery. The purpose of this study was to characterise the AVMs that were treated endovascularly with n-butyl cyanoacrylate and to evaluate the post-embolization results in the Cuban population. MATERIALS AND METHODS: From February 2006 to February 2011, a group of 58 consecutive patients with brain AVMs were embolized using n-butyl cyanoacrylate in the endovascular therapy unit of the Medical Surgical Research Centre in Havana (Cuba). In all, 91sessions were carried out with intranidal embolization and mainly partial devascularization, 25-30% per session, and closing 123 arterial pedicles. Safety times for n-butyl cyanoacrylate injection were established by calculating the polymerisation times for different dilutions, using post-embolisation hypotension systematically, as well as a superselective test with propofol to determine cerebral eloquence. RESULTS: Haemorrhagic signs were the initial presentation in 68.8% of the patients, 24.1% presented with epileptic episodes and 1.7% with ischemic stroke. Of the AVMs, 93.2% were supratentorial; according to the Spetzler and Martin classification, 13.8% were grade II, 56.9% were grade III, 22.4% were grade IV and 6.8%, grade V. One hundred and twenty-eight selective tests with propofol were performed and 118 (92.2%) of those were negative. Partial devascularization (20-30%) prevailed; complete obliteration was achieved in 17.2% of the patients and 70%-99% in 27.5% of the patients. Safety times for n-butyl cyanoacrylate injection were established and the use of post-procedure hypotension was settled. Morbidity of 17.2%, with 6.9% haemorrhagic complications and mortality of 3.4% were registered in the whole series. CONCLUSIONS: The rates of total occlusion and of morbidity and mortality in the series are in the internationally described ranges. The implementation of intranidal closings with 20-30% devascularization per session and the use of post-embolization hypotension after the haemorrhage complications described resulted in the total absence of haemorrhagic complications.