RT Journal Article SR Electronic T1 Trigeminocardiac reflex during the percutaneous injection of ethylene vinyl alcohol copolymer (Onyx) into a juvenile nasopharyngeal angiofibroma: a report of two cases JF Journal of NeuroInterventional Surgery JO J NeuroIntervent Surg FD BMJ Publishing Group Ltd. SP 263 OP 265 DO 10.1136/jnis.2010.003723 VO 3 IS 3 A1 Tommy A Potti A1 Joseph J Gemmete A1 Aditya S Pandey A1 Neeraj Chaudhary YR 2011 UL http://jnis.bmj.com/content/3/3/263.abstract AB The trigeminocardiac reflex (TCR) is a rare but well-described phenomenon encountered during invasive procedures involving the face, orbit, and cranial base. The reflex is characterized by the abrupt onset of hypotension, bradycardia, asystole, and dysrhythmias. With temporary cessation of the surgical procedure, vital signs typically stabilize without the need for further investigation, though anticholinergic drugs are often used to prevent prolonged hypotension and bradycardia. Two separate cases of the TCR were encountered during the percutaneous embolization of a juvenile nasopharyngeal angiofibroma with dimethylsulfoxide (DMSO) before the injection of ethylene vinyl alcohol copolymer (Onyx, ev3, Irvine, California, USA). In both cases, the injection of DMSO precipitated approximately 30 s of bradycardia/asystole, which then resolved after halting the procedure and administering anticholinergic drugs. There were no additional occurrences afterward and the patients underwent tumor excision with good recovery.