Utility of a freehand frameless navigation system in computed tomography-assisted ventral bulla osteotomy for otitis media in calves. - Tsuka, Takeshi; Yamahita, Masamichi; Okamoto, Yoshiharu; Miyazaki, Shunsuke; Ishii, Jun; Yoshimitsu, Kitaro; Muragaki, Yoshihiro (PLoS ONE, 2026)