[Evaluation of MRI for the staging of esophageal cancer]

The usefulness of MRI (magnetic resonance imaging) was evaluated in the diagnosis of the mediastinal invasion of esophageal cancer. MR examination was performed in 30 subjects without esophageal diseases and 23 patients with esophageal cancer. Normal esophagi and cancers were well visualized using T1-weighted image. In the axial section, every normal esophagus was contact to the aorta in the angle of less than 30 degree of the aortic circle. When the contact angle was less than 30 degrees, the stage of the cancer was below a1. When the angle was 30 degrees or greater, the stages were ranged from a0 to a3. In the oblique section orthogonal to the contact plain between the cancer and the aorta, the depth of the aortic invasion could be estimated. The sagittal scan was also helpful in the diagnosis of the invasion to trachea, left main bronchus and left atrium.