We report a case of a 23 year old male who suffered a traffic accident and had a suspicious widening of the mediastinum on chest x-ray. Computed tomography (CT) failed to demonstrate an aortic dissection. Due to the mechanism of injury and chest X-ray findings, we decided to perform a multiplane transesophageal echocardiogram (MTE). This revealed an aortic dissection of less than one centimeter in length and good heart function. Due to CT evidence of hemoperitoneum, the patient received an emergent laparatomy. A liver laceration and jejunal perforation were found and repaired. An intraabdominal abscess developed, which led to sepsis, multiple organ failure and ultimately death. MTE was used to monitor the status of the dissection and adequacy of heart function during his intensive care unit stay. The dissection extended to 4 cm in length by the second week and then remained stable. There was no thrombus formation within the false lumen by the third month. While the patient unfortunately died from complications related to his abdominal injuries, MTE not only diagnosed the traumatic aortic dissection when CT failed, but allowed easy monitoring of both the rate of extension and the flow patterns within the false lumen. This made prognostication and treatment planning much easier.