Intraoperative bleeding volume [ 3.5 2.7 ( 15-35 ) ml vs. 13.1 6.1 ( 4-25 ) ml ] and mean surgical time [ 7.6 4.5 ( 2-23 ) min vs. 23.6 4.4 ( 15-35 ) min ] in the Device Group were significantly less than in the Control Group ( P < 0.01 ) .