Abstract
Background. We have been developing endobronchial ultrasonography (EBUS) since 1994, and to date have examined 1500 cases and reported its usefulness. The most important indication, which can only be achieved with this method, is determination of the depth of tumor invasion of tracheobronchial lesions. We have reported on normal laminar layer images of the bronchial wall and comparisons between EBUS images and histopathologic findings. Method. In this report, we report laminar structures of the bronchial wall as visualized by a 30 MHz probe and the usefulness of 3D EBUS. Results. Compared with the laminar structures of the bronchial wall visualized by a 20 MHz probe, the marginal echoes of laminar structures were two-thirds thinner using a 30 MHz probe. Thus the 2nd and 4th layers were thicker and the 30 MHz equipment was useful to determine the depth of tumor invasion of tracheobronchial lesions by 30 MHz. The linear images of the bronchial wall by 3D EBUS were the same as the histopathologic findings.
