Demonstration of an inconspicuous right diaphragmatic hernia in a blunt trauma patient using CT multi-planar reformation.

The right diaphragmatic hernia is rare and often missed on initial radiological evaluations. Even a small tear in the right diaphragm can be gradually enlarged over time due to pressure differences between the abdominal cavity and thoracic cavity, resulting eventually in the abdominal contents entering into the thoracic cavity. We present a case of inconspicuous right diaphragmatic hernia which was missed at first thoracic radiograph and CT examination. After large portion of some abdominal contents herniated into thoracic cave, CT multi-planar reformation (MPR) demonstrated the changes directly and vividly depicted several signs of diaphragmatic hernia. As CT has become one of most important imaging modalities in the evaluation of thoracic and abdominal trauma, MPR can be used routinely to obtain a definitive diagnosis and improve radiologists' confidence of diaphragmatic hernia.