COVID-19 Technique Army Maj. (Dr.) Douglas Ruhl, a surgeon at Madigan Army Medical Center, Joint Base Lewis-McChord, Wash., uses the COVID-19 airway management isolation chamber to perform a mastoidectomy, which removes a growth behind the eardrum, Jan. 5, 2021. This procedure requires drilling into the skull, creating bone dust and aerosolized droplets. SHARE: Download: Full Size (0.27 MB) Tags: Army, coronavirus Credit: Army Maj. Douglas Ruhl VIRIN: 210105-F-HG842-001.JPG Photo Gallery