NxThera (St. Paul, MN) a development-stage medical device company focused on vapor ablation therapy for the treatment of endourology conditions, closed a $9M Series B financing, bringing the round total to $21.6M. Participants include American Medical Systems, Arboretum Ventures, Aberdare Ventures, GDN Holdings, Mitsui & Co., Premier Asia Capital, Alafi Capital and Prolog Ventures.