Acta Oto-Laryngologica

ISSN: 0001-6489 (Print) 1651-2251 (Online) Journal homepage: http://www.tandfonline.com/loi/ioto20

Postinflammatory Acquired Atresia of the External Auditory Canal P. Bonding & M. Tos To cite this article: P. Bonding & M. Tos (1975) Postinflammatory Acquired Atresia of the External Auditory Canal, Acta Oto-Laryngologica, 79:1-2, 115-123, DOI: 10.3109/00016487509124663 To link to this article: http://dx.doi.org/10.3109/00016487509124663

Published online: 08 Jul 2009.

Submit your article to this journal

Article views: 10

View related articles

Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ioto20 Download by: [University of California, San Diego]

Date: 20 April 2016, At: 22:03

Acta Otolaryngol 79: 115-123, 1975

POSTINFLAMMATORY ACQUIRED ATRESIA O F THE EXTERNAL AUDITORY CANAL

P. Bonding and M. Tos From the E N T Clinic, Gentofte Hospital, Copenhagen, Denmark

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

(Received March 22, 1974)

Abstract. Seventeen cases of postinflammatory acquired atresia of the external auditory canal in 14 women are described and analysed. Fourteen of these cases were solid atresias in which the auditory canal was more or less filled with fibrous tissue. Three patients had partial membranous atresia. The aetiology was external otitis and/or chronic otitis media. The formation of atresia is usually by jerks, and its steps are as follows: External otitis with destruction of the epithelium, formation of granulations, fibrosing of the granulations, and lining with new meatal skin.

Acquired atresia of the auditory canal is fairly uncommon. Aetiologically it may be sub-divided as follows: Post-traumatic atresia arising as a rsult of severe, direct or indirect, trauma, such as shotgun injuries (Conley, 1946), severe contusions of the ear (Proud, 1956), and impression fractures of the anterior meatal wall with displacement of the mandibular neck (Anthony, 1957). It may also follow upon burns, thermal, chemical, or electric (Proud, 1956; Cohen, & Fox, 1943). Postoperative atresia arises as an early phenomenon following otosurgery, and in rare cases after surgery on the parotid gland (Proud, 1956). Furthermore, neoplastic atresia may occur when a malignant tumour from the auditory canal or its surroundings entirely occludes the auditory canal (Mitchell, 1940; Work, 1950). The aetiology and pathogenesis of these three varieties are evident and easy to understand. As a rule these cases are preceded by stenosis, whereupon total closure takes place because of granulations. The presupposition of atresia is that the skin is damaged in the entire

circumference of the auditory canal. Between the atresia and the drum the meatal epithelium may be preserved, and a meatal cholesteatoma results. The main object of the present communication is to describe a fourth variety of acquired atresia, posinflummatory acquired atresia. Only a few cases of this type are on record, and its pathology, aetiology, or pathogenesis do not appear to have been entirely elucidated. PREVIOUS INVESTIGATIONS In the literature we have found only seven cases of postinflammatory acquired atresia. Novick (1939) reported membranous atresia in a man with a history of recurrent meatal complaints many years ago. Work (1950) described bilateral acquired atresia following chronic otitis media. Gundersen (1960) described three cases of acquired meatal atresia. In the first case the atresia was found to consist of fibrous tissue. Close to the drum there was a plate of newformed bony tissue. In the second case the atresia was situated laterally in the auditory canal. Between it and the intact drum were large exostoses and cholesteatoma-like epithelial masses. In the third case the atresia was 5 mm lateral to the drum. Between the drum and the atresia there was fibrous connective tissue. Eichel & Simonton (1965) reported on a patient who developed, following external otitis, bilateral fibrous atresia 3 mm lateral to the drum. Acta Otolaryngol79

116 P. Bonding and M . Tos Table I. Presentation of material 7 I

FIRST OTOSCOPY

FURTHER COURSE

HEARING AID

POSSIBLE AETIOLOGY

HEARING AIRIBONE

DISEASE

O E

LO110

1960-1965

OMC

LO110

1965-1972

OMC

LO110

RECURRENT 0 E IN 1967, 1969 A N D 1970

O E

60110

1356 NORMAL DRUM NORMAL M E 1961 0 E WITH GRANULATIONS ON T H E DRUM

RECURRENT 0 E IN 1966, 1967 1969 AND 1970

O E

60110

1957 INTACT, SLIGHTLY FIBROUS DRUM E M NORMAL 1966 0 E

RECURRENT O E

O E

80115

1966 SMALL, MOIST CENTRAL P E R F O RATION 0 E

CONSTANTLY DISCHARGE

1967 LARGE.MOIST CENTRAL PERFORA TION 0 E

DISCHARGE UNTIL 1970, DRY EAR SINCE

1960- 1973

O M C

90130.

1962 LARGE MOIST C E N T R A L PERFORC TION

RECURRENT

FROM 1962

OMC

50110

O E

1961 GRANULATIONS ON THE DRUM 1969 INCIPIENT ATRESIA

7ECURRENT 3 E I N 1971 4 N D 1972 ZROGRESSIN( 4TRESIA

1960 LARGE DRY C E N T R A L PERFORATION E M NORMAL

9ECURRENT DISCHARGE AND 0 E

1960 LARGE MOIST C E NTRAL PER FORATION, E M NORMAL

RECURRENT DISCHARGE AND 0 E

1956 AND 1961 NORMAL DRUM NORMAL E M 1966 ATTACK OF C E CHRONIC O E

RECURRENT ACUT O i I T S MEDIA l k CHILDHOOC PERCEPTIL 72 DEAFNESS

O E O F 1 MONTHS DURATION I f

DURING SEVERAL YEARS

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

16

OMC

3

DURING SEVERAL YEARS

16

I3

5 6

70

OMC

1956 - 1966

04 I

c

55/25

53

61

9

OMC SINCE CHILOHOO

50

1969 INCIPIENT ATRE S l A DRY

-

OMC= Otitis m-,dia chronica. O E = Otitis externa. EM = External auditory meatus.

The fibrous tissue contained many dilated blood vessels. Marlowe ( 1 972) described a patient who developed bilateral atresia with meatal cholesteatoma four months after an infection in both auditory canals.

MATERIAL AND RESULTS The material consists of 14 patients with postinflammatory acquired atresia in a total of 17 ears, as in three cases the atresia was bilateral (Table I). Acta Otolaryngol 79

Incidence During a two-year period we have collected twelve cases of postinflammatory acquired atresia among 3 770 audiological patients over 14 years of age-an incidence of one atresia in about 300 patients. In a retrospective review of 600 patients who had tympanoplasty, we found two patients with postinflammatory acquired atresia, corresponding to an incidence of one atresia per 300 tympanoplasties. A striking finding was that all the patients were females. Among the 7 patients on record, 5 were males.

Postinflammatory acquired atresia

117

--

I

FIRST OTOSCOPY

FURTHER COURSE

HEARING AID

POSSIBLE AETIOLOGY

DISEASE

+ OMC SINCE CHILOHOOO

1957 AND 1962 LARGE MOIST CENTRAL. P E R F O RATION 1962 DRY P E R F 0 RATION

OE

FROM 1962 1968 DRY, INCIPIENT ATRFSl A

FROM 1962

O M C

PERCEPTIVE

1960 NORMAL DRUM E M NCRMAL

FROM 1968 RECURRENT O E 1969 I N C I PIENT ATRESIA

FROM 1968

O E

FROM 1968 CHQONIC

1956- 1969

O E

FROM 1969

O E

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

1951 AND 1965 NORMAL DRUM E M NORMAL

13 14

CTOSCLERO

1965 DRY F E N E STRATION CAVITY E M NORMAL

OPERATION ;;gSCLERC

1965 DRY F E N E STRATION CAVITY

O E

FROM 1970 CHRONIC

O E W I T H 015CHARGE RECURRENT

O E

OE

1958 FENESTRATION OPERL 71 TlON

15 30

% YEARS EA N L;

1955 LARGE.DRY CENTRAL PERFORATION

RECURRENT DISCHARGE

0 MC

1962 MINOR D I S CHARGING CAVITY W I T H GRANULATIOh

DRY F R O M 1963

O M C

1963 LARGE PERFORATION OF T H E DRUM

CONTINOUS DISCHARGE DRY FROM 1965

OMC

PERCEPTIVE DEAFNESS

ATTICO-ANTROTOMY

17

OSlMNEE CHILDHOOD

25

Two patients were 21-40, 5 were 41-60, and 7 were 61-80 years of age. The youngest was 25 and the oldest 80 (Table I), mean 56 years.

PATHOLOGY In most cases the atrcsia was situated mediaIly, i.e. in the osseous part of the auditory canal, in 4 cases in the middle of the meatus, at the junction of the cartilaginous and osseous part (Table I, Cases 8-10 and 16, Fig. l), and in 2 cases laterally (Cases I 1 and 12). The meatus lateral to the atresia was somewhat narrow in one of the patients, who had moist eczema (Case 7), but no cther patients had stenoses. In several cases the lateral part was even rather wide. Just before the atresia the auditory canal narrowed from all sides, ending in an epithelial-lined atre-

tic plate. In 5 patients, moreover, the meatal skin lateral to the atresia was eczematous and rather moist. In 5 cases there was dry, scaly external otitis (Fig. 2), while in the remaining 6 the meatal skin was normal. Physical examination, radiography, and operation disclosed two types of atresia: (1) solid atresia and (2) membranous, web-type atresia.

Solid atresia In solid atresia the auditory cam1 between the atretic plate and the drum may be filled, either with ( a ) fibrous tissue, (b) fibrous tissue with cholesteatoma, or (c) fibrous and osseous tissue. (a) Solid fibrous atresia was found in 13 cases (Table I, Cases 1-12, Case 17). Six were treated by operation (Cases 1-3, 10, 12, and 17):which disclosed between the atretic plate and the drum, Actu Otoluryngol 79

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

118 P. Bonding and M . Tos occupied by fibrous tissue of the same histological architecture as described above. Apart from this, there was anteriorly, in the inferior part of the auditory canal, close to the drum, a well-defined cholesteatoma. The lamina mucosa and drum were intact, and there was no cholesteatoma in the tympanic cavity. In 1936 this patient had undergone attico-antrotomy because of chronic otitis media. In 1962 there was a small cavity, but no atresia of the auditory canal. The cavity wall was lined with granulations which had presumably spread inferiorly and anteriorly, so that the epithelium from the inferior tympano-meatal angle became surrounded by granulations. (c) Solid fibrous-osseous atresia was not found in the present material, but has been described by Gundersen (1960). Membranous atresia

Membranous atresia was present in three cases (Table 1, Cases 13-15), but the membrane was not quite closed. Two patients had previously had otosclerosis treated by fenestratioc which functioned for many years. The skin in the cavity was very thick and the cavity

Fig. I . Solid atresia after chronic otitis media. Developed after treatment with hearing aid (Case 9).

firm, fibrous tissue, characterized histologically by connective tissue containing numerous capillaries and non-specific sub-chronic or chronic inflammatory changes. The fibrous tissue was adherent to the lamina propria of the drum, but could easily be separated and removed from the mucous layer. In cases where a perforation of the drum had been demonstrated previously (Cases 2 , 3, and 10) operation showed that in this site the mucous layar was intact and the perforation had healed. However, an exception was found in Case 17 in which the middle ear housed a cholesteatoma arising from the margins of- the perforation. The osseous parts of the auditory canal and of the middle ear were normal. (b) Solid fibrous atresia with meatal cholesteatoma was observed in one case (Case 16). At operation the greater part of the atresia was Actu Otoluryngol 79

,

Fig. 2. Solid atresia with epithelial-lined granulations in the central area. Dry eczema in the auditory canal (Case 3).

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

Postinflammatory acquired atsessia

119

was almost completely obliterated. Through the apxture in the atretic membrane the drum could be seen moving normally. Medial to the atresia the meatal skin was eczematous and moist, The third patiznt (Case 15) had chronic otitis media with a large central perforation of the pars ttnsa. The auditory canal between the atresia and the drum was filkd with granulations arising partly from the middle ear and partly from the auditory canal.

external otitis occurred there too, and so did atrzsia. In patients having a tendency to external otitis, occlusion of the auditory canal by an earmould will-by reason of local irritation, increaxd moisture, and possibly allergy to the inaterial in the mould-aggravate the external otitis and cause accumulation of moist debris in th- innermost part of the auditory canal. This form; the basis of the local changes which may 1 x 3 t2 the formation of meatal atresia.

AETIOLOGY

PATHOGENESIS

it was common to all 17 of the present cases that prior to the development of atresia there had been an inflammatory condition in the auditory canal and/or middle ear. Chronic or recurrent external otitis was in 8 cases the direct cause of the atresia (Table I, Cases 4-6, 11-14). In these cases the drum had been, when first examined several years ago, intact, and the meatus had been normal. Four patients (Cases 6, 11, 12, 13) developed external otitis 6 to 12 months after they had been fitted with hearing aids. It had persisted or recurred for some years, and had been localized in the main medially and close to the drum. In the remaining 9 cases the patients had primarily had chronic otitis media (Cases 2, 3, 7-10, 15-17). For years before the atresia developed, they had had chronic or recurrent aural discharge, and when first seen several years ago they had exhibited perforation of the drum. Four patients (Cases 2, 3, 9, 10) had a normal auditory canal when first seen, but thereafter developed external otitis after they started using hearing aids. A total of 6 patients had, besides the chronic otitis media, definitely had chronic external otitis for some years before the atresia appeared. in the remaining 3 cases the external otitis was probably present for some part of the course. Within the entire material 9 patients had been wearing hearing aids for years before the atresia appeared. In two, with bilateral atresia (Cases 2,3, 12, 13) the external otitis and the subsequent atresia occurred first in the ear in which the hearing aid treatment was started. After the hearing aid had been shifted to the other side,

In solid fibrous atvesia the auditory canal fills, gradually or by jerks, with fibrous tissue, starting on the drum and progressing lateralward. i n most patients we have b-en able to trace the course of the disease several years back. In one patient (Table I, Case 1) the formation of the atresia was regularly observed by us. i n 1964 this patient, who had no previous history of meatal complaints, developed severe unilateral external otitis which persisted for 4 months despite treatment. On the drum there were granulations, whereas the lateral part of the meatus was only mildly involved (Fig. 3 A). The granulation subsided, and the drum became re-epithelized; thereafter, it was somewhat thickened, mobile, but withydistinct details. i n 1969 the patient had anotheryattack of external otitis and the process was repeated. At paracentesis and tubulation under the operation microscope the atresia was 14 mm thick, immobile,rand consisted of firm, fibrous tissue covering the handle of the malleus (Fig. 3B). The middle ear was aerated and the middle-ear mucosa normal. In 1971 an identical attack occurred, and the atresia increased in thickness by another +-1 mm. In 1972 the patient again developed marked formation of granulations atIthe site of the atretic plate and medially in the auditory canal. The granulations started peripherally in the atretic membrane and in the meatal wall, spreading towards the middle, and the original epithelium disappeared completely. Gradually, epithelium grew from the meatal skin over the granulations which decreased in size and grew firmer (Fig. 4). At the operation Acta Otolaryngol 79

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

120 P. Bonding and M . Tos

Fig. 3. Schematic representation of the development of solid atresia (Case 1). (A): First attack of otitis externa, with granulations on the ear-drum and the resulting

thickened, fibrous ear-drum after re-epithelization (1964). (B, C ) The subsequent attacks, progressing atresia after each attack (1969 and 1972).

the entire atretic membrane, except for a small area in the middle, was lined with meatal skin (Fig. 3C).

In this case the solid fibrous atresia grew jerkily over several years, and the same process went on repeating itself: External otitis with denudation of the epithelium and formation of granulations medially in the auditory canal, fibrosing of the granulation tissue, and lining of the granulations with meatal skin. The primary factor of the process was necrosis of the meatal skin and denudation of all epithelial elements. Signs of a similar course were observed in other patients in whom the aetiology was external otitis and in whom the drum as well as the auditory canal were originally normal. They had recarrent external otitis (Cases 4-6, 10-1 2), formation of granulations on the drum (Case 5), or incipient atresia which progressed in the course of the subsequent years (Case 11). The observed level of the atresia can probably not be considered the final state, as the atresia may spread further laterally. At re-examination of the non-operated cases one year later, we found that in One the cutaneous lining Of

Fig. 4 . Development of solid atresia. Central part moist, with granulations, peripheral part lined with skin (Case 1). Actu Otolaryngol 79

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

Postinflammatory acquired atresia 121 the atresia had disappeared, being replaced by new granulations. In cases that started as chronic otitis media with perforation of the drum (Cases 2, 3, 7, 8-10) the perforation of the drum must have closed in the first stage of formation of the atresia. In the operated cases (Cases 2, 3, lo) the inside of the drum proved to be lined with mucosa. The subsequent development of atresia presumably takes place in the way described above. After the formation of atresia had started, the discharge decreased, and the patients had thereafter had only recurrent external otitis (Case 9) or an entirely dry ear for some years (Cases 2, 3, 8-10). The condition for non-occurrence of cholesteatoma in the auditory canal is that all the squamous epithelium from the drum or the edge of the perforation must be destroyed before it gets covered with granulations. In two cases, however, operation revealed cholesteatoma. In the former (Case 17) the cholesteatoma sac was situated in the tympanic cavity. It had arisen from the edge of the perforation which was not lined with mucosa, so that the sac was in direct contact with the fibrous atretic tissue. It is difficult to tell whether the atresia had formed after or before the invasion of the cholesteatoma sac into the tympanic cavity. In the latter case (Case 16) there was, as already mentioned, a cholesteatoma anterior in the auditory canal, close t o the drum which was incidentally intact. The cause of cholesteatoma formation was presumably that the atresia coursed from the roof to the floor of the auditory canal and thus enclosed epithelial remnants inferiorly, unlikc the solid fibrous atresia which coursed from the drum laterally. The pathogenesis of membranous atresia is different from that of solid atresia. According to Work (1950) the formation of a membrane laterally in the auditory canal is due to filling of the auditory meatus with pus and detritus, resulting in special local irritation at a given level of the meatus. There will be ulceration in the entire circumferenc:, and granulations will form. The granulations get epithelized from both

- 10

125

250

500

1000

2000 LOW

BOX

0 10 20

30 LO

50 60 70

80 90 - o o l110

Fig. 5. Progressing air-bone gap during the development of solid atresia (Case I), as illustrated in Fig. 3.

sides, and a membrane results. The epithelium of the auditory canal and drum will be enclosed, with accumulation of epithelial masses, behind the atretic membrane. The reason why the membrane did not close completely in our cases may be that the skin in the medial part of the auditory canal was still affected with external otitis with discharge (Cases 13, 14). The third patient (Case 15) still has active chronic otitis media with formation of granulatjons, arising partly from the middle ear and partly from the medial part of the auditory canal (Case 15). The pathogenetic process in the web-type atresias has presumably not yet been completed, and the membrane may close entirely. On the other hand, it is conceivable that the epithelium medial to the atresia may be destroyed upon renewed formation of granulations, the granulations may undergo fibrosis, and the aperture in the atretic membrane may close. Thus, the web type of atresia may become solid, fibrous atresia. HEARING For most of the patients audiograms are available for the time before atresia formed, but the great majority had even then considerable hearing loss of the conductive type, either because of chronic otitis media with perforation or otosclerosis. Some had perceptive hearing loss. In one patient a relationship between the growth of the atresia and the hearing loss could be demonstrated (Table I, Case 1). After the first Acta Otolaryngol 7 9

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

122 P. Bonding and M . Tos DISCUSSION

attack of granulation formation in I964 (Fig. 5), when the drum was merely rendered somewhat thicker, but r,-main-d mobile, the hearing was 15 dB. After the second attack in 1969, when the drum increased in thickness to 1 4 mm and became immobile, hearing decreased to 30 dB, and at the most r x m t attack in 1972, when the atresia had become 7 mm thick, the hearing was 40 dB. Table I gives the hearing in the frequency range 500-2 000 Hz at the most recent examination. In 3 patients (Cases 1-3) exhibiting at operation a normal middle ear and a normal ossicular chain, the air-bone gap was 30 dB, and in one patient (Case 16) it was 50 dB. In a few others, not subjected to operation, in whom radiography indicated that the middle ear was normal, there was an air-bone gap of 30-60 dB (Cases 4-9). The most pronounced hearing loss occurred during incipient atresia formation. Later, the hearing did not decrease essentially, even despite a manifold increase in thickness of the atresia. TREATMENT Once the atresia has developed, the only effective treatment is surgery. Seven patients (Table I, Cases 1-3, 10, 12, 16, 17) underwent operation in which the atresia was completely excised and the auditory canal as well as drum were covered with free skin grafts. In the same stage other pathological changes in the middle ear were treated. The technique and results will be published elsewhere. Laterally situated atresias involve rather difficult problems in re-epithelialization of the auditory canal and drum. In patients who have had medially situated atresias, early operation is preferable. Removal of granulations from the drum may perhaps prevent the occurrent? of the atresia. As treatment of patients with external and chronic otitis by means of a hearing aid presumably promotes the formation of atresia, annual follow-up of such patknts may disclose incipient signs of this proczss. Acta Otolzryngol 79

,

The aetiological classification of acquired atresias suggested in the presmt paper seems justified, as the aetiology of traumatic, postoperative, and neoplastic a t m i a s is evident. It has also been demonstrated in the przsent study that recurrent external otitis, alone or combined with chronic otitis media, may be the cause of postinflammatory acquired atresia. In our opinion, therefore, this term is adequate for the disease and clearly distinguishes it from other types of atresia. Postinflammatory atresia does not appear to be as rare as previously assumed. It will be found especially among elderly patients who have been wearing a hearing aid for many years or who have been fitted with a hearing aid for an ear with perforation of the drum. No doubt the improved audiological service and following-up of these patients is contributory to the increasing incidence of acquired atresia. Although the diagnosis of a full-blown atresia is easy, incipient formation of atresia with granulations on the drum may give rise to diagnostic considerations pointing to acute and chronic otitis media and tumours. Shambaugh (1969) has described a state of chronic granulation formation on the drum, chronic myringitis. This condition seems to resemble the initial stage of postinflammatory acquired atresia with which it is possibly identical. However, in atresia the granulations arise from the meatal skin close to the drum. Solid postinflammatory atresias are more common than the web-typz ones, whereas among the post-traumatic cases the web type is more common than solid atresia (Conley, 1946). This is understandabls, as it is a precondition for the occurrence of web-type atresia that a circular injury to Lhe meatal skin occurs lateral to the drum.

ZUSAMMENFASSUNG Bei 14 Frauen wurden 17 Falle mit postinflammatotischen Gehorgangsatresien beschrieben und analysiert. Bei 14 Fallen war die Atresie solide, und der Gehorgang war

Postinflammatory acquired atresia 123 ganz ode1 teilweise mit fibrosem Gewebe ausgefiillt. Bei drei Fallen war die Atresie membranos. Die Atiologie war Otitis externa undioder Otitis media chronica. Die Atresie wird in der Regel ruckweise gebildet, unter folgenden Prozessen: Otitis externa mit Auflosung des Epithels, Bildung und Fibrosierung des Granulationsgewebes, uberdeckung des Granulationsgewebes rnit neuer Gehorgangshaut.

Downloaded by [University of California, San Diego] at 22:03 20 April 2016

REFERENCES Anthony, W. P. 1957. Congenital and acquired atresia of the external auditory canal. Arch Otolaryngol 65, 479. Cohen, L. & Fox, S. L. 1943. Atresia of the external auditory canal. Arch Otolaryngol 38, 338. Conley, J. J. 1946. Atresia of the external auditory canal occurring in military service. Arch Otolaryngol 43, 613. Eichel, B. S. & Simonton, K. M. 1965. Stenosis of the external auditory meatus secondary to chronic external otitis treated by a simplified surgical method: Report of case. Laryngoscope 75, 16.

Gundersen, T. 1960. Atresia Meatus Acusticus Externus als Folge von Otitis externa eczematosa. Acta Otolaryngol (Stockh) 52, 473. Marlowe, F. T. 1972. Acquired atresia of the external auditory canal. Arch Otolaryngol 96, 380. Mitchell, H. E. 1940. Tumors of the external auditory canal. With a report of eleven cases. Arch Otolaryngol 32, 831. Novick, J. N. 1939. Atresia of the external auditory meatus. Arch Otolaryngol 30, 144. Proud, G . 0. 1956. Stricture of the external auditory canal. Laryngoscope 66, 72. Shambaugh, G. E. 1969. Surgery of the ear, p. 247. W. B. Saunders Co. Philadelphia & London. Work, W. P. 1950. Lesions of the external auditory canal. Ann Otol Rhino1 Laryngol 59, 1063.

M. Tos, M.D. E N T Clinic Gentofte Hospital DK-2900 Hellerup Danmark

Acta Otolaryngol 79

Postinflammatory acquired atresia of the external auditory canal.

Seventeen cases of postinflammatory acquired artresia of the external auditory canal in 14 women are described and analysed. Fourteen of these cases w...
1MB Sizes 0 Downloads 0 Views