During the procedure, {TAIL ~ the surgeon} manipulates active electrode 6 and performs {HEAD ~ directed coagulations} 
During the procedure , { TAIL ~ the surgeon } manipulates active electrode 6 and performs { HEAD ~ directed coagulations }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD