Eustachian tube opens in middle ear in-

70. Ans: b. Anterior wall (Refer: PL Dhingra, Diseases of Ear, Nose & Throat, 7th edition, pg no. 61) Eustachian tube   Cylindrical channel connecting tympanic cavity & nasopharynx called Pharyngotympanic tube Opens in the anterior wall of middle ear Epithelium – Ciliated columnar epithelium Length – 36 mm (Lateral 1/3 bony & Medial 2/3 fibrocartilaginous) Position – Placed at angle of 45 ͦ with sagittal plane Muscles of ET – Tensor palati supplied by branch of mandibular nerve & Levator palate supplied by pharyngeal plexus of 11th nerve Neurovascular supply Arterial supply Venous drainage Nerve supply Ascending pharyngeal artery Middle meningeal artery Artery of pterygoid canal Pterygoid venous plexus Tympanic plexus