Does MRI show if eustachian tube is normal? If no so which scan do I have to do?

No. Mri cannot directly visualize the eustachian tube in high detail - it is usually a thin collapsed line on the exam across several slices. Mri can offer secondary clues to eustachian tube dysfunction if there are abnormal lesions in or along its course, especially at its terminus in the lateral nasopharynx. Ct of the temporal bones would offer the best opportunity to visualize it along its length.
Eustachian tube. Function is assessed by an ENT using tools such as nasopharyngoscopy, tympanometry, and pneumatic otoscopy. Mri may have a place in further evaluation should the ENT specialist believe it would add value, primarily in the visualization of tube anatomy and possible secondary involvement of the tube in nasopharyngeal disease.