Myringoplasty. Surgical repair of tympanic membrane perforations

Observations on Tympanic Membrane Perforations (Safe Type) and Hearing Loss

The most commonly observed clinical findings in otological practice is discharging ear in which perforation of the tympanic membrane is the commonest, yet the patients hardly ever seek advice for deafness as the presenting symptom. In patients with the symptoms of ear ache or ear discharge when relieved seldom present for follow up and are not very much concerned about the hearing loss present there. There is a different correlation between surface area of tympanic membrane and amplification of sound. Conductive hearing loss is seen in lower tones than higher tones. When the surface area of tympanic membrane is reduced in case of perforations there is decreased in amplification of sound waves. Hearing loss is less in smaller perforations than in larger ones and more for lower tones than for higher tones. A perforation has more serious effect on hearing when it is located in the vicinity of the attachment of malleus. Perforations situated in the postero-inferior quadrant will cause more hearing loss than in other quadrants. The aim of the study is to know the exact location and exact size of perforation and to make a comparative study on the amount of hearing loss produced respectively-in cases of central perforations. Data of 100 patients was collected and studied from May 2015 to April 2016. Hearing loss is related to site and size of perforation with postero-inferior quadrant perforations caising more degree of hearing loss. It varies between 2 and 25 dB more at lower 2 frequencies. Hearing loss is related to size and site of perforation. Small perforation in the postero-inferior quadrant cause more hearing loss than a perforation of same size in other quadrants. Similarly the size of perforation also affects the amount of hearing loss.

Conductive hearing loss associated with pressure equalization tubes

Pressure equalization (PE) tube placement traditionally has been used to lessen conductive hearing loss with chronic middle ear effusion. It is assumed that the small diameter of the tube should not interfere with the conduction of sound. In this article we present 5 patients in whom placement of a PE tube resulted in significantly worse conductive hearing. Occlusion of the PE tube with cigarette paper or Gelfoam improved hearing, as documented with audiometry. The average conductive hearing losses attributable to the ventilation tube for this series of patients were 22, 17, 15, 13, 4, and 10 dB at the frequencies of 250, 500, 1000, 2000, 4000, and 8000 Hz, respectively. This amount of change attributable to PE tubes in this small selection of patients is much greater than would be commonly appreciated. We conclude that the opening in the tympanic membrane provided by PE tubes can potentially result in a significant conductive hearing loss. Discussion includes those conditions in which reduced hearing may be more likely to occur.

Conductive hearing loss associated with pressure equalization tubes

Pressure equalization (PE) tube placement traditionally has been used to lessen conductive hearing loss with chronic middle ear effusion. It is assumed that the small diameter of the tube should not interfere with the conduction of sound. In this article we present 5 patients in whom placement of a PE tube resulted in significantly worse conductive hearing. Occlusion of the PE tube with cigarette paper or Gelfoam improved hearing, as documented with audiometry. The average conductive hearing losses attributable to the ventilation tube for this series of patients were 22, 17, 15, 13, 4, and 10 dB at the frequencies of 250, 500, 1000, 2000, 4000, and 8000 Hz, respectively. This amount of change attributable to PE tubes in this small selection of patients is much greater than would be commonly appreciated. We conclude that the opening in the tympanic membrane provided by PE tubes can potentially result in a significant conductive hearing loss. Discussion includes those conditions in which reduced hearing may be more likely to occur.

Myringoplasty: hearing gain in relation to perforation site

One hundred perforations of the tympanic membrane with successful myringoplasties have been reviewed. A partially reversible impairment of bone conduction was noted, being more obvious in posterior and subtotal perforations. It was also shown that the site of perforation affects the degree of hearing loss and the degree of subsequent improvement after myringoplasty; marginal and malleolar perforations had a greater hearing loss and less post-operative hearing improvement than central and non-malleolar perforations. It was also shown that posterior perforations had a greater hearing loss than anterior perforations.

Hearing loss in perforations of the tympanic membrane

70 patients with dry central perforations have been studied to assess the hearing loss. The hearing loss is greater at the lower frequencies and increases with the size of the perforation. Malleolar perforations cause more hearing loss than the non-malleolar unless the perforation involves less than 10 per cent of the tympanic membrane surface area. Perforations of the postero-inferior quadrant cause more hearing loss than those in the antero-inferior quadrant.

THE USE OF VEIN HOMOGRAFTS IN TYMPANOPLASTY

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