Pancreaticoduodenectomy with malrotation following reoperation due to torsion of efferent loop: a case report oleh Yumiko Kageyama, Ryuzo Yamaguchi, Shinya Watanabe, Keiji Aizu, Shinichiro Kobayashi, Fumiya Sato, Hironori Fujieda, Yoshitaka Toyoda, Tsutomu Iwata