<prompt> Eustachian tube opens in middle ear in-flooranterior wallSuperior wallPosterior wall  <response>: 70. Ans: b. Anterior wallRefer: PL Dhingra, Diseases of Ear, Nose Throat, 7th edition, pg no. 61Eustachian tube Cylindrical channel connecting tympanic cavity nasopharynx called Pharyngotympanic tubeOpens in the anterior wall of middle earEpithelium Ciliated columnar epitheliumLength 36 mm Lateral 13 bony Medial 23 fibrocartilaginousPosition Placed at angle of 45 with sagittal planeMuscles of ET Tensor palati supplied by branch of mandibular nerve Levator palate supplied by pharyngeal plexus of 11th nerveNeurovascular supplyArterial supplyVenous drainageNerve supplyAscending pharyngeal arteryMiddle meningeal arteryArtery of pterygoid canalPterygoid venous plexusTympanic plexus 