Diagnostic accuracy of oblique chest radiograph for occult pneumothorax: comparison with ultrasonography. - Shokei Matsumoto; Kazuhiko Sekine; Tomohiro Funabiki; Tomohiko Orita; Masayuki Shimizu; Kei Hayashida; Taku Kazamaki; Tatsuya Suzuki; Masanobu Kishikawa; Motoyasu Yamazaki; Mitsuhide Kitano (World Journal of Emergency Surgery, 2016)