Fig. 2

Histological morphology of eustachian tube of miniature pig (right ET, axial). A, Whole view of eustachian tube and surrounding tissue. B, view of the gland (asterisk) rich area of ET lower segment lumen (4 × power field views of red box in A). C, view of the cartilaginous ET from the ET pharyngeal opening (4 × power field view of black box in A). D, Higher magnification micrograph of the tubal microstructure (red square in C) shows epithelium (black arrow) with crypt, thin connective tissue (red arrow) between the cartilage (red triangle) and epithelium, a few gland (asterisk), vessel (red arrow) and in the mesenchymal tissue (black triangle) underlying the epithelium. E, Higher magnification micrograph of the tubal microstructure (black square in B), shows epithelium (black arrow), crypt (white arrow), thick connective tissue (black triangle), vessel (red arrow) between the cartilage (red triangle) and epithelium, abound gland (asterisk) and mesenchymal tissue underlying the epithelium. ET-OCT image from the ET pharyngeal opening (F) and ET lower segment lumen (G), shows cartilage (red arc line), epithelium (white arrow), connective tissue (white triangle), gland (red arrow), vessel (white asterisk)