The human ear
The human body is remarkable andit is very complex. It is made of many organs and many systems. Furthermore,the human body has five senses. One of these senses is the sense ofhearing. The main organ through which the sense of hearing is manifestedis the ear, which is a part of auditory system.
The human ear is also verycomplex. It is made of three major parts: the outer ear, the middle ear and theinner ear. All these three parts are also comprised of some parts. Therefore,the outer ear is made of ear flap and ear canal; the middle ear is comprised ofeardrum or tympanic membrane and three tiny bones (hammer, anvil and stirrup);and the inner ear is made of spiral tube, semicircular canals and the auditorynerve.
Tympanic membrane or eardrum isthe part of the middle ear. It is very thin, extremely delicate and, therefore,susceptible to many diseases or disorders. The tympanic membrane islocated at the end of the external ear canal, which is 2 cm long. The eardrumhas the appearance of a flattened cone with its apex pointed inward, while itsouter surface is slightly concave.
The uppermost small area of themembrane where the ring is open is under no tension; this part is known as thepars flaccida. The majority of the membrane is tightly stretched; this iscalled the pars tensa. The loose part of the TM, or the pars flaccida, borderson the pars tensa from the above and it is considerably smaller, aboutone-eighth the size of the pars tensa.
Thesound waves from the outer ear come to the middle ear as pressure waves. Themain role of the tympanic membrane is to conduct the waves to the middle earthrough the ossicles, which are three tiny bones. The tympanic membraneamplifies the waves and forms a shield with the round window of the labyrinthagainst direct sound waves. Furthermore, tympanic membrane also has the role toprotect the gentle mucosa of the middle ear from the external factors.
Myringitis is the medical termfor the inflammation of tympanic membrane. The main symptoms of this earcondition are earache, hearing impairment and sensation of congestion. If thiscondition is not treated within three weeks, it becomes subacute and itprogresses and develops into chronic myringitis.