Assessment of Long-Term Middle Ear Ventilation

Abstract

Pathologic changes of the middle ear cavity are almost invariably caused by eustachian tube malfunctions which are either permanent, fluctuating or recurrent. The process may deteriorate from middle ear effusion to atelectasis of the middle ear, adhesive otitis, and can potentially end in cholesteatoma. Close association with eustachian tube malfunction is common in the following conditions: cleft palate, allergy, obstructive lymphoid hypertrophy, hypoimmune state, etc. Negative intratympanic air pressures typify the above conditions, leading to the progressive pathology of the ear drum and cavity. Localized atelectatic retraction pockets signal the alarm of impending irreversible complications. They may be localized in any part of the eardrum, predominantly in the posterosuperior quadrant. Inpocketed by the continuous vacuum, these invaginations may fill with trapped epithelial debris. Re-establishment of adequate middle ear ventilation is the key in every attempt to arrest and reverse this pathology. Clinical, photographic, tympanometric and manometric documentations are presented to demonstrate the reversibility of even far advanced cases. This was achieved by the application of long-term silicon ventilating tubes in 203 ears. 1 744 ears treated with standard home-made polyethylene tubes served as controls. The following period covered six years. The standard tubes retained their position for an average of six months, the comparable figure for the long-term tubes was thirty-six months. In 53% of the ears, the retraction pockets were eliminated and in 29% their progress was checked. Hearing improved in 93 % throughout the study period. Complications occurred in 22% of the long-term ventilated ears. This study demonstrates that with minor surgical intervention, far-advanced seemingly irreversible, pathology in the middle ear and mastoid cavity may often be arrested. Immediately following insertion of the tubes the air bone gap is closed and optimal hearing is secured. This approach, if employed early enough, with persistence, may postpone or even render many complicated and difficult major surgical procedures unnecessary. It is preferable and easier both for the patient and for the surgeon, to ventilate the tympanic cavity for prolonged periods in an attempt to control the deterioration to adhesive otitis and cholesteatoma, rather than to correct them with intricate surgery that is not fail-proof and has many inherent risks.