tokens: BACKGROUND : The purpose of this study was to compare surgical conditions , including the amount of intraoperative bleeding as well as intraoperative blood pressure , during functional endoscopic sinus surgery ( FESS ) using flexible reinforced laryngeal mask airway ( FRLMA ) versus endotracheal tube ( ETT ) in maintaining controlled hypotension anesthesia induced by propofol - remifentanil total i . v . anesthesia ( TIVA ) .