Læknablaðið - 01.06.1972, Blaðsíða 42

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LÆKNABLAÐIÐ
recovered in all cases, with normal hearing regained in three cases. In no
cases was there deterioration of hearing. The principle of the Bellucci
method is that the normal part of the stapes footplate is separated from
the diseased one and subluxated by pushing it down with a polyethylene
strut placed between the footplate and the lenticular process.
The present paper outlines the various pathologic conditions of the
tympanic membrane and middle ear and some of the methods of recon-
structive surgery practiced today.
Myringoplasty in general is discussed, with special reference to the Shea
method, which is the method preferred by the author. In most cases cubital
vein tissue taken from the patient himself was used as a graft. The vein
was excised the day before the operation and left in the wound until needed.
In the case of one child, a vein graft from a patient operated on the day
before was used. In the case of another child, pericard tissue was used as a
graft. The results were excellent and lasting in both cases.
During the past two years, the innovation of cutting a small slit in the
graft before positioning it and inserting a polyethylene tube No. 90 in the
slit has been employed. The tube, which provided adequate drainage, was
removed a few days later, depending on the secretion.
Some of the more common operative procedures for reconstruction of
the defective ossicular chain are described.
Remnants of the incus have most frequently been used by the author
for reconstructing the sound conducting mechanism of the middle ear. In
some cases, however, a polyethylene strut, wire or homograft bone has been
used. In two cases where the incus and the arch of the stapes were missing,
the stapes footplate and the tympanic membrane were connected with a
series of superimposed vein „rolls" a.m. Offermann.
A few case histories with pre- and post-operative audiograms are pre-
sented.
The results of 120 cases of tympanoplastic surgery are presented. The
ears had been dry for at least three months. Sequelae of chronic otitis with
perforation of the eardrum was the most common condition. In some cases,
there was a defective ossicular chain in addition to the perforation.
The material contains a few cases of traumatic rupture of the tympanic
membrane, traumatic dislocation of the incus, and fracture of the stapes.
The results of the operations are based upon pure tone audiometry,
which was performed at least two months post-operatively. The figures
refer to average hearing level for the speech frequencies.
The results aie divided in two categories:
The first category covers the first 100 cases of myringoplasty performed
by the author. Average hearing improvement was 24 dB, ranging from five
dB to 65 dB. Serviceable or normal hearing was obtained in 85% of these
cases. In 93% of the cases the air-bone gap closure was either complete or
within 15 dB. In six of these cases there was a total perforation. In these
cases, average hearing improvement was 23 dB, ranging from 15 dB to 40
dB, with all patients regaining serviceable hearing.
All patients in this category improved in hearing. Omitted, however, are
four ears where myringoplasty was unsuccessful due to exessive post-
operative secretion. In four of the 100 cases, a tiny perforation occurred at
the junction of the graft and eardrum post-operatively but without noticeable
hearing impairment. Recurrence of perforation some years after operation
occurred in three cases caused by acute otitis media. One of these healed
spontaneously.
The latter category covers 20 cases of type II and III tympanoplasty.
In 12 of these cases where the greatest part of the long proeess of the incus
was missing remnants of the incus were repositioned to the stapes. Of these,
nine cases showed hearing improvement from 15 dB to 35 dB, with service-
able hearing in nearly all cases and air-bone gap 0-25 dB. In three cases,
however, there was no hearing improvement, probably due to adhesion of
the incus to the tympanic wall. This hypothesis is based on the fact that