L a h a r p t T he trigeminocardiac reflex (TCR) is a well-defined phenomenon consisting of the sudden onset of parasympathetic dysrhythmia, sympathetic hypotension, apnea, or astric hypermotility during stimulation of any of the sensory ranches of the trigeminal nerve (7). Clinically, the TCR has been eported to occur during craniofacial and ophthalmologic surgery or many years; in neurosurgery, it was first described in 1999 uring surgical treatment of a cerebellopontine angle tumor (6). he TCR has been reported in several other procedures owing to he long course of the trigeminal nerve at the skull base, such as icrovascular decompression, transsphenoidal operations, and urgery for tumors around the falx. The experience of Cho et al. urther enlarges the series of reports that disclose the TCR as a ossible event during transsphenoidal surgery in the wall of the avernous sinus.