There was no difference in the proportion of wounds that were closed surgically ( 75-mmHg group , 50 percent ; 125-mmHg group , 60 percent ) , wounds that demonstrated 50 percent wound area reduction ( 75-mmHg group , 65 percent ; 125-mmHg group , 80 percent ) , or wounds that demonstrated 50 percent wound volume reduction after 4 weeks of therapy ( 75-mmHg group , 95 percent ; 125-mmHg group , 90 percent ) .