Atticotomy, Attic Reconstruction, Tympanoplasty with or Without Ossiculoplasty, Canal Plasty and Cortical Mastoidectomy as Part of Intact Canal Wall Technique for Attic Cholesteatoma

Abstract

To evaluate a technique of canal wall up mastoidectomy for limited attic cholesteatoma and to study practical considerations during surgery. Any person undergoing surgery for attic cholesteatoma was thoroughly examined during surgery and decision for doing this canal wall up (CWU) surgery will be taken on operating table. The patients were regularly followed up and microscopic, oto endoscopic and audiological assessments done at regular intervals. Revision surgery was done only if there were signs of recidivism or if ossiculoplasty was planned for second stage or placement of a prosthesis later was considered. Out of 100 cholesteatoma surgeries, 22 cases found suitable for the CWU technique. Only 1 out of 22 patients required revision surgery due to recurrence. Rest of the patients maintained healthy middle ear for more than a year. Prevention of medialisation of attic cartilage piece was found to be very important consideration. The CWU technique is a reliable method of management for limited attic cholesteatoma. Selection of subjects should be very meticulous.

Introduction

Management of unsafe type of chronic otitis media (COM) generally requires surgical intervention. In order to obtain more physiological environment in ears after surgery, several canal preserving techniques are used. Atticotomy, contemporaneous reconstruction of lateral epitympanic wall and tympanoplasty with cartilage/perichondrium, indicated to be a reliable treatment and prevention technique for epitympanic cholesteatoma. It can achieve good morphological and functional results [1]. Post auricular approach atticotomy with reconstruction of the scutum is a useful technique to remove cholesteatoma from the anterior epitympanum [2].

The current study aims to evaluate the practical considerations of the method and observation for any complications after atticotomy, reconstruction of lateral attic wall and tympanoplasty. A cortical mastoidectomy is also done in all the cases. Canal wall is preserved in all the cases. Selection of cases suitable for this technique has to be very meticulous and the decision to employ this technique is to be taken on the operating table after thorough microscopic examination of the extent of the disease, being ready to convert into a canal wall down procedure at any point of time if the disease demands. The most suitable cases are those with limited attic cholesteatoma with no or minimal involvement of mesotympanum with or without mastoid involvement. Ossicular involvement or involvement of anterior attic are not contraindications for this technique and proper ossiculoplasty can be combined with this procedure or can be done in a second stage. Any case with serious intratemporal and/or intracranial complication is excluded from this study.

Materials and methods

Pre operative evaluation includes thorough clinical examination, microscopic examination, pure tone audiogram and fitness for general anesthesia. All patients are explained regarding possibility of a second stage surgery and an informed written consent also taken for the same. The procedure begins with a post auricular incision and harvesting of temporalis fascia graft. Vascular strip incisions used for the best exposure. Canal incision at 12 o’clock is made more anteriorly to obtain better visualization of anterior attic. Drill work started at the scutum area, to reach the fundus of the cholesteatoma sac. Attic cholesteatoma is classified into type I and II. If the cholesteatoma has only reached the surface of the malleo-incudal joint, it was regarded as type I. If the cholesteatoma has entered the anterior attic space and destroyed the malleo-incudal joint, it was regarded as type II [3]. In addition to this, we observed another pattern of disease where the cholesteatoma is going more posteriorly and destroys the Incus partially or completely, whereas sparing the head of Malleus. This sac may also extend into the mastoid area through the aditus.

According to the extent of cholesteatoma sac, partial or complete removal of the lateral attic wall is done. The mesotympanum is inspected carefully for any involvement by the disease. If the sac is not involving any ossicles and not extending into the mastoid, the whole of the sac can be exteriorised with careful dissection. Significant involvement of mesotympanum would require alternative methods of surgical intervention. A cortical mastoidectomy is done in all cases. If the cholesteatoma is extending into the mastoid area, then the sac is lifted and dissected from all sides and through the aditus, the sac everted into the attic area. At any point of time, if there is any doubt regarding completeness of removal, then the procedure is converted into a canal wall down mastoidectomy. Involvement of the tip of mastoid is also not a contraindication. Inspection of anterior attic is of crucial importance. If required, careful drilling of anterior scutum and anterior canal wall in superior part will give good visualization of anterior attic. If the cholesteatoma sac is going medial to the head of malleus, then tilting of malleus head with tensor tympani still attached at the neck of malleus is done. This also gives a good visualisation. Excision of head of malleus is done if the head is engulfed by the cholesteatoma sac or if the sac cannot be dissected off from the head. Thinning of posterior canal wall done as required to visualise a part of cholesteatoma sac otherwise out of view. Excessive thinning is avoided. The middle ear cavity, attic and mastoid area are thoroughly flushed and irrigated with saline for any retained squamous debris.

Reconstruction of attic is carried out by a piece of tragal cartilage (Fig. 1). The piece is kept in such a way that it forms the lateral wall of attic. The size and shape of the piece are decided according to the area of defect created by drilling or disease. The piece is supported from medial side by ossicular heads when present and by putting abundant gelfoam if ossicular heads are absent, in order to prevent medialisation. Partial obliteration of aditus was carried out by temporalis muscle where it was found to be very wide. Small defects that remain after reconstruction with a cartilage piece are filled up by bits of temporalis muscle or smashed cartilage. Temporalis fascia kept lateral to the piece of cartilage and also to cover any defects in tympanic membrane by underlay method. Adequate gelfoam kept in mesotympanum, mastoid and also in the ear canal. Appropriate ossicular reconstruction also carried out when necessary. The patients are advised to maintain strict follow up for at least 2 years and as and when required thereafter. After 6 weeks of surgery, thorough microscopic examination carried out. Oto endoscopic pictures taken on subsequent visits and the pictures recorded for future comparison (Fig. 2).

Fig. 1.

Cartilage piece being kept for attic reconstruction

Fig. 2.

Post operative result at 1 year

Results

100 ears were operated in 2 years, where 22 cases (22 %) were included in the study who met the inclusion criteria. Amongst them, 11 were males and 11 females. Most of the patients were between 20 and 40 years age. Only 4 patients were between 50 and 60 years of age. Atticotomy, disease removal, attic reconstruction, tympanoplasty, canal plasty and cortical mastoidectomy carried out in all of them under general anesthesia. Table 1 shows the distribution of disease in different areas.

Table 1.

Distribution of disease in different areas of middle ear and mastoid and status of ossicles

Involvement of area	No of patients	MSI	MS	NIL/M
A	7	7
A, Ad	4	1	3
AA	1	1
A, Ad. M1	6		5	1
A, Ad, M2	4			4
Total	22	9	8	5

A Attic; A, Ad attic and aditus; AA anterior attic; A, Ad, M1 attic, aditus and limited mastoid; A, Ad,M2 attic, aditus and extensive mastoid involvement; MSI all ossicles present and mobile; MS Malleus handle and Stapes present and Incus partially or completely eroded; Nil/M all ossicles absent or only a part of Malleus present

There were 7 (31.8 %) patients where only limited attic involvement was found. The disease was confined to middle or posterior part of attic and not involved the anterior attic or the aditus area. In all these patients, all the three ossicles were present and the ossicular chain was intact and mobile. In 4 (18.2 %) patients, the disease extended in attic and also the aditus area, blocking communication between the middle ear and mastoid. In 3 of them, the long process of incus found to be partially eroded, and 1 of them had an intact ossicular chain. There was one case where only the anterior attic and Prussack’s space were involved in disease and ossicular chain was intact and mobile. Mastoid involvement was seen in 10 (45.5 %) cases, where limited involvement in upper part was present in 6 patients, whereas 4 cases had extensive mastoid involvement. Anterior attic was significantly involved in 2 of these cases. The patients were followed up for minimum 1 year and longest follow up available for 2 years with an average of 16 months. Only 1 patient (4.5 %) developed recurrence of disease, where revision surgery in the form of a canal wall down procedure had to be performed 4 months after the primary surgery. Rest 21 cases did not have recurrence during the follow up period. Two of the cases developed sagging of posterior canal wall, which recovered with anti inflammatory medications and local Betamethasone+Neomycin ear drops. All patients with intact ossicular chain (8 cases) had post op air bone gap (ABG) less than 15 db. Malleus–Stapes assembly with the help of a cartilage piece was carried out in 4 patients, where the post op ABG was observed to be less than 30 db, with an average of 24.2 db. No deterioration of bone conduction suggestive of sensory-neural loss was observed in any of the 22 cases. In 4 patients, the long process of Incus was partially eroded and a small piece of cartilage was used to bridge the gap between stapes head and remaining of Incus. In 2 of the patients, only stapes was present where a type III cartilage shield tympanoplasty [4] was carried out. In 4 patients, all ossicles were absent and no ossiculoplasty was performed in them. They were scheduled for a second stage procedure but the patients refused for the same as the other ear had normal hearing and they did not want to undergo another surgery only for improvement of hearing.

Discussion

With increasing awareness regarding health of ears, more patients seek medical advice when there is limited involvement of ear with attico-antral disease. Clinical examination is useful only for diagnostic purpose. CT scan of temporal bone can guide regarding the extent of disease but the decision of doing either a canal wall up or canal wall down procedure has to be taken during surgery after contemplating the true extent of disease and gaining confidence regarding completeness of removal of disease. Various modifications and techniques have been described in literature for canal wall up procedure. Farrior [5] has described a technique of anterior–posterior mastoidectomy. Tos [6] had described a technique of intact canal wall (ICW) which includes trans-canal atticotomy, drilling of anterior canal wall, post-auricular mastoidectomy and maximum thinning of superior and posterior bony canal wall with good results. He also concludes that treatment of cholesteatoma should be individualized, that no single method is preferable in all cases, and that an intact ossicular chain should be preserved. Glasscock et al. [7] have mentioned that the intact canal wall tympanoplasty is a procedure that will gain acceptance and will be more widely used in the future. It was a routine practice to do a second look procedure in all cases of ICW surgery. Reimer et al. [8] have quoted a high rate of recidivism and a second stage surgery in most cases of ICW technique in 1987. With time, new modifications came for ICW and very few patients require a second surgery. Mahadeviah and Parikh [9] have advised thinning of the rim of posterior canal wall in order to visualize sinus tympani area and most of the patients did not require a second stage surgery. A second look surgery was required in 4.8 % cases due to residual or recurrent disease. In the current study, the patients were asked to maintain strict follow up and revision surgery was performed only when required. Table 2 shows comparison of recidivism rates with other studies.

Table 2.

Comparison of recidivism rates of different studies

Study	Recidivism rate
Current	4.5
Glasscock et al. [5]	14
Mahadevaiah et al. [6]	4.8
Deng et al. [1]	0

Conclusion

Atticotomy, attic reconstruction, tympanoplasty with or without ossiculoplasty, canal plasty and cortical mastoidectomy as intact canal wall technique for attic cholesteatoma is a reliable method for selected cases. The case selection has to be very meticulous and good follow up is essential. Rate of recidivism is minimal with the technique.