Three-Dimensional Reconstruction of the Thoracic Descending Aorta with Multiplane Transesophageal Echocardiography

Transesophageal 2-dimensional echocardiography, which provides high quality images of the thoracic aorta, is generally adequate for only diagnosis. However, it is difficult to obtain a 3-dimensional structure of the anatomy and the full extent of pathology. Therefore, the purpose of this study is to evaluate the feasibility of generating 3-dimensional images of the descending thoracic aorta from sequential 2-dimensional transesophageal echocardiographic images, and assess the optimal display technique to provide the morphologic information. The number of subjects consisted of 19 : 4 with normal aorta, 7 with ischemic heart disease, 4 with valvular heart disease and 4 with aortic dissection. To obtain 2-dimensional images of the aorta, a probe was inserted to about 40 to 45 cm from the ncisor. After optimizing the image characteristics, the 2-dimensional images of the aorta were taken every 2 mm by manually withdrawing the probe. Each 2-dimensional image was recorded using a VTR during two or three beats. Three-dimensional reconstruction was carried out by using distant shading and gradient shading with a computer workstation. In almost all cases, 3-dimensional reconstruction could be achieved. In patients with normal aorta, the aortic inner surface was reconstructed as a smooth wall. However, in patients with atherosclerosis, it was reconstructed as a rough wall with various protrusions of different sizes. Especially, in case of aortic dissection, three-dimensional reconstruction could demostrate the spatial anatomy (true lumen, false lumen, and intimal flap), and the dynamic 3-dimensional (4-dimensional) image demonstrated the movement of the intimal flap. In conclusion, 3-dimensional reconstruction has advantages for estimating of the thoracic aorta and its dynamics.

経食道心･血管エコー図法

三次元再構築

大動脈疾患