TITLE: Cholesteatoma: Pathogenesis and Surgical Management
SOURCE: Dept. of Otolaryngology, UTMB, Grand Rounds Presentation
DATE: February 24, 1999
RESIDENT: Kyle Kennedy, M.D.
FACULTY: Jeffrey Vrabec, M.D.
SERIES EDITOR: Francis B. Quinn, Jr., M.D.

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"This material was prepared by resident physicians in partial fulfillment of educational requirements established for the Postgraduate Training Program of the UTMB Department of Otolaryngology/Head and Neck Surgery and was not intended for clinical use in its present form. It was prepared for the purpose of stimulating group discussion in a conference setting. No warranties, either express or implied, are made with respect to its accuracy, completeness, or timeliness. The material does not necessarily reflect the current or past opinions of members of the UTMB faculty and should not be used for purposes of diagnosis or treatment without consulting appropriate literature sources and informed professional opinion."


 

Introduction

Cholesteatoma (keratoma) represents the presence of a non-neoplastic accumulation of keratinizing stratified squamous epithelium along with desquamated keratin debris in the tympanic cavity and/or mastoid. Once the squamous epithelium reaches these areas from its origin in the external auditory canal or tympanic membrane, a locally invasive and destructive process typically ensues. The rate of progression of the disease process is usually insidious and inexorable but may be quite variable depending on the clinical circumstances. Signs and symptoms are dependent on the location and extent of disease. Cholesteatoma may remain clinically silent for a significant period of time until the disease has become quite extensive. Hearing loss and otorrhea are common manifestations, but other, more serious, intratemporal and intracranial complications may arise. Surgical therapy is the mainstay of management. The primary surgical objective is eradication of all diseased tissue with establishment of a dry, safe ear. Maintenance or restoration of hearing is a secondary goal. Management of cholesteatoma requires prolonged, diligent postoperative follow-up due to the significant rate of recidivistic disease.

This discussion will involve pathogenesis and management of cholesteatoma with an emphasis on management of the disease. Some underlying concepts regarding establishment of the pathologic process will be mentioned, as well as anatomical considerations pertinent to effective management of the condition. A great deal of controversy remains as to the most effective surgical management of cholesteatoma. The various surgical techniques employed will be outlined, followed by treatment results which have been obtained with different approaches to cholesteatoma removal.

Pathology and Classification of Cholesteatoma

Although in clinical use for many years, the term cholesteatoma is somewhat of a misnomer in that the lesion is not a neoplasm, nor is cholesterol present. The term keratoma, as applied by Schuknecht, affords a more appropriate description of the lesion. Histopathologically, cholesteatoma demonstrates the presence of keratinizing stratified squamous epithelium with keratin debris and an underlying subepthelial fibroconnective tissue. Granulation tissue with an acute and chronic inflammatory cell infiltrate may be evident as well. Bone destruction or resorption may occur as a consequence of expansion of the cholesteatoma mass and/or elaboration of collagenase and other enzymes and inflammatory mediators. Different types of cholesteatoma exist and are broadly classified as congenital or acquired. A separate and unusual type is the canal cholesteatoma.

The vast majority of cholesteatomas are acquired, with a much smaller number of cholesteatomas which are congenital in origin. The clinical features of these lesions are significantly different. The canal cholesteatoma deserves brief mention as well.

Congenital cholesteatoma is usually diagnosed in children of preschool age and may arise in the middle ear or within the tympanic membrane. Congenital cholesteatoma involving the middle ear is usually evident as a white or pearly mass medial to the anterosuperior quadrant of an intact tympanic membrane. Congenital cholesteatoma arising in the tympanic membrane is rare and may involve different portions of the drum. Associated hearing loss may be minimal, but the visible portion of the cholesteatoma may only represent a small portion of a much more extensive lesion than is apparent on initial inspection. Irrespective of the location, congenital cholesteatomas are defined by a specific set of criteria which have been set forth and refined by various authors:

Acquired cholesteatoma is usually diagnosed in older children and adults and with a previous history of middle ear disease. The cholesteatoma is most often found in the posterosuperior quadrant of the tympanic membrane with the associated presence of tympanic membrane retraction and/or perforation. Hearing loss is typically manifest with more extensive disease. Acquired cholesteatoma may be further subdivided into primary or secondary. Primary acquired cholesteatoma arises in the clinical setting of accumulation of squamous debris in a pre-existing retraction pocket. Secondary acquired cholesteatoma is most often accompanied by a perforation of the tympanic membrane with subsequent migration of squamous epithelium into the middle ear.

Canal cholesteatoma is found lateral to the tympanic membrane. Pain and otorrhea are typical findings. Several varieties are noted. The spontaneous variant is idiopathic, while a post-traumatic canal cholesteatoma may arise as a result of acquired canal stenosis. Finally, an iatrogenic form may be the result of a flap complication following a prior otologic procedure. The idiopathic form is typically encountered in older individuals, while the traumatic variety is often seen in younger patients. Iatrogenic canal cholesteatoma may arise at any age. Canal cholesteatoma must be distinguished from keratosis obturans, a condition resulting from the accumulation of keratin debris secondary to loss of the normal self-cleansing mechanism of the external auditory canal.

Eustachian Tube Dysfunction

The importance of eustachian tube dysfunction as it relates to the pathogenesis of middle ear disease and cholesteatoma cannot be overstated. Poor tubal function plays an essential role recurrent disease and failure of surgical therapy.

The most recent Grand Rounds concerning the topic of otitis media presented an excellent overview of eustachian tube anatomy and physiology and these points will not be repeated here. Recall that the main functions of the eustachian tube include pressure regulation, protection, and clearance. Failure of any one or all of these functions may lead to persistent negative middle ear pressure, effusion, and tympanic membrane retraction. Wide excursions in middle ear pressure may lead to tympanic membrane atrophy, atelectasis, retraction pocket formation, or perforation. Tympanic membrane pathology is most likely to occur in the attic, and the degree of pathology usually correlates with the degree of eustachian tube dysfunction. Development of cholesteatoma may ensue.

Clinical assessment of tubal patency and function may be achieved with inspection, pneumatic otoscopy, observation of autoinsufflation capability, and tympanometry. Retraction disease with a lack of middle ear aeration, inability to autoinsufflate, and type C or B tympanogram are indicative of poor tubal function.

Tubal function and middle ear aeration are particularly important in terms of postoperative hearing results. As an example, Tos et al assessed hearing results 3 to 9 months postoperatively in children treated for cholesteatoma and chronic otitis media. Significantly better hearing was noted in the those patients with a positive preoperative Valsalva’s maneuver when compared with those with a negative Valsalva’s maneuver.

Pathogenesis of Cholesteatoma

The epithelium of the external aspect of the tympanic membrane and that encountered in cholesteatoma are known to migrate. It is this migratory capability that undoubtedly plays a significant role in the accumulation of keratin and squamous debris in an established retraction pocket and the extension of skin into the middle ear through a persistent tympanic membrane perforation.

Several theories exist which may explain the mechanism of cholesteatoma development. Iatrogenic implantation of squamous epithelium into the middle ear via tympanostomy tube insertion or tympanoplasty may occur, with subsequent cholesteatoma formation. Invasion of squamous epithelium into the middle ear via a persistent tympanic membrane perforation is probably the most commonly accepted etiology behind formation of a secondary acquired cholesteatoma. The invagination theory has been suggested as a mechanism for formation of a primary acquired cholesteatoma. This theory proposes that an underlying abnormality in attic mucosa results in decreased aeration with localized retraction pocket development leading to cholesteaoma formation.

Congenital cholesteatoma formation within or medial to an otherwise normal, intact tympanic membrane has several possible etiologies, such as basal cell proliferation within the squamous epithelium as a result of tympanic membrane alterations induced by inflammation. The cones of epithelial proliferation may then expand within the tympanic membrane itself or extend medially into the middle ear proper. Metaplasia of normal middle ear mucosa from chronic inflammation is another possibility. Embryonic squamous epithelial cell rests within the middle ear mucosa could also proliferate to form an accumulation of squamous epithelium leading to cholesteatoma.

Anatomic Considerations in Cholesteatoma

The tympanic cavity develops embryologically from the endodermally-lined first branchial pouch. A number of mucosal folds and ligaments subsequently develop within the tympanic cavity in association with the ossicular chain, and this results in the creation of characteristic pathways for the extension of cholesteatoma throughout the tympanic cavity and antrum. A basic knowledge of the anatomy of this area provides a foundation for understanding disease progression and sound concepts for its surgical management.

A cholesteatoma is most likely to develop in the attic or epitympanum or the posterior mesotympanum. In the epitympanum, this includes Prussack’s space. This space is bounded by the neck of the malleus medially, par flaccida laterally, lateral process of the malleus and its associated horizontal folds inferiorly, and the lateral mallear fold superiorly. Cholesteatoma may extend from here to other areas by one of several routes including lateral to the incus posteriorly toward the antrum and inferiorly toward the posterior mesotympanum. Cholesteatoma in the anterior epitympanum may involve the facial nerve or extend into the supratubal recess.

In the posterior mesotympanum, the facial recess and sinus tympani are anatomic features with which one should be familiar. The posterior mesotympanum is an area which commonly harbors residual cholesteatoma due to these areas, which are often difficult to access surgically. The facial recess is bounded by the facial nerve, fossa incudis superiorly, and chorda tympani nerve laterally. The sinus tympani is located medial to the fallopian canal between the canal and medial wall of the posterior mesotympanum. Severe retraction of the tympanic membrane may occur into these recesses of the posterior mesotympanum, and cholesteatoma may be difficult or impossible to visualize directly and remove no matter which surgical approach is employed. A posterior tympanotomy via a facial recess approach may be helpful in this area, and endoscopic assessment may sometimes prove useful for removal of diseased tissue in the sinus tympani.

Evaluation

History

A careful otologic history must be obtained in order to elicit the early, subtle symptoms of cholesteatoma since the disease may remain essentially asymptomatic until involvement has become quite extensive. A previous history of middle ear disease such as tympanic membrane perforation or chronic otitis media may become evident. Progressive hearing loss, usually unilateral, may be reported, and infection of the cholesteatoma may lead to foul-smelling otorrhea. Unfortunately, the patient may not become symptomatic nor seek medical attention until symptoms become troublesome. Symptoms such as headache, ear pain, facial paresis/paralysis, and vertigo indicate possible impending intratemporal or intracranial complications and should prompt immediate assessment and treatment.

Physical examination

The physical examination consists of a thorough head and neck examination with particular attention to the otologic exam. A general overall assessment of the patient is necessary to avoid overlooking fever, subtle changes in mental status, or other findings which might afford clues to the development of a potential complication.

Otomicroscopy is the primary means by which the presence and extent of cholesteatoma may be ascertained during the physical examination. Thorough aural toilet is necessary for removal of any otorrhea, debris, or crusting which may hinder adequate visualization. The tympanic membrane should examined closely. A retraction pocket may be seen and is most often located in the attic or posterosuperior quadrant of the tympanic membrane. An accumulation of squamous debris may be seen within the pocket. Should there be a tympanic membrane perforation, an assessment of the middle ear mucosa should be attempted with regard to the presence or absence of edema or granulation tissue and character of any drainage. With extensive granulation, a frank aural polyp may develop and be seen to emanate from a perforation. Extreme caution should be exercised with polyp removal, as the polyp may be adherent to important underlying structures. Very careful sharp debridement may afford an extended view of the other pathology which is present, but bleeding can be troublesome. An initial assessment of the ossicles is helpful, but the ultimate status is best determined at operation. Inspection and pneumatic otoscopy to establish eustachian tube function and middle ear aeration are performed, but it may be necessary to infer tubal function based on the status of the contralateral ear.

Weber and Rinne tests with 512 Hz tuning fork are most likely to indicate a conductive hearing loss and should be compared with subsequent audiometric findings. Failure to observe appropriate correlation with the expected results may prompt further investigation, such as imaging studies.

Audiology

Pure tone audiometry with air and bone conduction, speech reception thresholds, and word recognition usually establish a conductive hearing loss in the affected ear. The degree of conductive loss will vary considerably depending in the extent of disease. Tympanometry findings will vary as well and may suggest decreased compliance or tympanic membrane perforation. A sensorineural component should create suspicion of further complications.

Imaging

Preoperative imaging is unnecessary for many patients, particularly those undergoing an initial procedure in which there is no evidence to suggest the presence of a complication other than perhaps conductive hearing loss. In this instance, computed tomography of the temporal bone is not likely to provide much additional information but will certainly aid in the assessment of mastoid disease and provide a surgical road map. However, temporal bone CT is indicated for revision cases and those in which sensorineural hearing loss, vestibular symptoms, or other evidence of complication exist.

Management of Cholesteatoma

Cholesteatoma is a surgical disease, but, depending on the clinical circumstances, non-surgical management options may be appropriate for some patients. Patient age plays a prominent role in the therapeutic decision-making process. For instance, childhood cholesteatoma is generally considered to be a more aggressive disease process than that encountered in adults. The fundamental disease process is most likely the same in children and adults. However, a set of conditions may exist in childhood cholesteatoma which make it more difficult to treat. For instance, poor tubal function in children may lead to episodes of recurrent otitis media or otitis media with effusion with associated inflammation promoting increased proliferation of squamous epithelium. Formation of further tympanic membrane retraction may result in recurrent cholesteatoma. A well-aerated pediatric mastoid may facilitate extension of disease. This situation mandates timely and thorough surgical intervention to eliminate disease and minimize the potential for future adverse sequelae. On the other hand, the elderly patient may be a poor surgical candidate due to the presence of comorbid conditions and have a primary acquired cholesteatoma with a retraction pocket which is perfectly amenable to routine aural toilet in the office. A number of other factors must also be considered when determining an appropriate course of therapy, and a final decision can sometimes only be made intraoperatively.

As mentioned previously, management goals for cholesteatoma include eradication of the disease with establishment of a safe, dry ear. Preservation of as much normal anatomy as possible with maintenance or improvement of hearing is a secondary consideration. Management of complications, should they arise, may initially take priority over the other management objectives.

Non-surgical Management

It may not be possible to offer surgical therapy to all patients with a cholesteatoma, such as an elderly patient with a poor general medical condition. Depending on the extent of disease, it may be possible to manage the cholesteatoma in the office with otomicroscopy and aggressive aural toilet. Thorough cleaning at routine intervals with removal of all accessible squamous debris may be adequate to prevent extension of the disease process and development of infection and other complications. This regimen is particularly useful in those patients in whom disease is limited to an attic or posterosuperior retraction pocket that allows adequate visualization and access. A reliable and cooperative patient is essential.

Topical antibiotic therapy may prove useful in alleviating otorrhea, but access of the medication to all areas involved with the disease process is often not possible, and the effectiveness may therefore be limited. Preparations containing steroids may help decrease the amount of granulation tissue and afford better visualization at surgery. Unfortunately, in many instances it is simply not possible to achieve a completely dry ear prior to performing surgery.

Surgical Management

The following is an overview of the various procedures employed in the management of cholesteatoma. The important features of the different approaches will be emphasized with regard to their utility in removal of cholesteatoma from specific locations in the middle ear and mastoid. There has been no consensus as to the most efficacious procedure for management of cholesteatoma, and the continued high rate of recidivism underscores this point. The principal controversy surrounds intact canal wall versus canal wall down mastoidectomy for removal of disease, and results of these two methods will be reviewed in the next section. The approach to a given ear case is based on many factors, including those relating to the ear itself, as well as other general patient considerations. It is essential that management of cholesteatoma be highly individualized on a case-by-case basis.

As with any surgical procedure, careful preoperative patient counseling is mandatory. The following points should be explained and clarified prior to the procedure:

Tympanostomy tube insertion with middle ear aeration may be beneficial in alleviating early tympanic membrane retraction associated with eustachian tube dysfunction. If the pathologic process can be arrested before atelectasis, deepening of the pocket, and other possibly irreversible changes have occurred, then development of a cholesteatoma may be averted. Retraction disease will likely persist in the face of severe eustachian tube dysfunction despite tympanostomy tube placement with subsequent progression of the disease process and formation of an acquired cholesteatoma. In a similar fashion, tympanoplasty for repair of a persistent perforation may fail in the setting of severe eustachian tube dysfunction. The importance of tubal function in the successful management of cholesteatoma and other chronic middle ear diseases cannot be overstated.

For smaller congenital cholesteatomas limited to the mesotympanum and those within or adherent to the tympanic membrane, adequate access may often be achieved via a transcanal approach with elevation of a tympanomeatal flap. Adequate tubal function with aeration of the middle ear and mastoid is important in these instances. Excision of the cholesteatoma from the tympanic membrance often necessitates tympanoplasty. Acquired cholesteatomas limited to the mesotympanum may often be accessed via an endaural or postauricular approach with surgical manipulation of the middle ear only followed by tympanoplasty.

Intact canal wall mastoidectomy consists of preservation of the posterior bony external auditory canal wall during simple mastoidectomy with or without a posterior tympanotomy. The posterior tympanotomy is achieved through a facial recess approach via a triangular area bounded by the fossa incudis, chorda tympani nerve, and facial nerve. Intact canal wall mastoidectomy is suitable in cases with a cholesteatoma in the attic, antrum, and possibly the posterior mesotympanum with an adequately aerated middle ear and mastoid. A staged procedure is often necessary with a scheduled second look at 6 to 9 months for removal of residual cholesteatoma and ossicular chain reconstruction. Staging becomes important in the presence of extensive abnormalities of middle ear mucosa, residual cholesteatoma, and ossicular erosion.

Canal wall down mastoidectomy involves removal of the posterior canal wall to the level of the vertical facial nerve. A mastoid cavity is created with exteriorization of the mastoid into the external auditory canal. The scutum or lateral wall of the epitympanum is removed with obliteration of the epitympanum and removal of the head of the malleus and incus. In the modified radical mastoidectomy variant, the middle ear space is maintained, while in the radical mastoidectomy, the middle ear space is eliminated and the eustachian tube obliterated. This approach is indicated as the initial procedure under the following circumstances:

Some of these factors may be evident preoperatively, while others may only be assessed at surgery. The presence of inadequate middle ear aeration and a sclerotic mastoid are relative indications.

Other maneuvers may be required with a canal wall down procedure. A meatoplasty is necessary with the canal wall down mastoidectomy to facilitate egress of desqaumated epithelial debris and provide access to the mastoid bowl. Mastoid obliteration provides a means of decreasing the size of the mastoid cavity to avoid bowl complications such as accumulation of debris with subsequent infection as well as caloric effects of an open mastoid cavity. Obviation of the need for periodic cleaning is another objective. Various flaps have been advocated for this purpose, along with the use of bone pate or bone chips. Components of the tissues employed are often noted to atrophy during the first few years following surgery, and this results in a concomitant increase in the size of the cavity. Loss of the initial benefits gained with attempted mastoid obliteration further emphasizes the importance of a well-done meatoplasty and diligent routine follow-up.

Atticotomy entails removal of the scutum for for access to limited attic disease. The scutal defect is subsequently reconstructed, usually with autologous cartilage, to reduce the possibility of retraction pocket formation and development of recurrent cholesteatoma.

The Bondy procedure consists of removal of the scutum and posterior canal wall with preservation of the ossicles and middle ear space. This approach is adequate for larger attic cholesteatomas located lateral to the ossicle in patients with a sclerotic mastoid.

The various procedures all have advantages and disadvantages. Since the two primary concepts of the approaches are those of the intact canal wall or canal wall down mastoidectomy, the strong and weak points of each are summarized below.

Intact canal wall advantages:

Intact canal wall disadvantages:

Canal wall down advantages:

Canal wall down disadvantages:

Whatever the chosen approach, complete eradication of disease should remain at the forefront of the surgical decision-making process.

Results of Therapy

A great deal of debate exists as to the most appropriate surgical technique for the management of cholesteatoma. Much of the controversy surrounds the use of intact canal wall vs. canal wall down mastoidectomy. Many prominent otologic surgeons have considerable differences of opinion in this matter, and there are strong proponents of both approaches. Treatment results are variable in terms of eradication of disease and hearing, and there has been no consensus as to a universally effective treatment strategy. Due to the nature of the cholesteatoma disease process, a meaningful randomized, prospective clinical study is difficult to implement. Anatomy, extent of disease, and other circumstances may necessitate one approach or another in an individual case. When considering postsurgical results, it is often impossible to accurately assess whether the finding of further disease represents residual or recurrent cholesteatoma. For this reason, results are often reported in terms of recidivism, which encompasses both residual and recurrent disease.

Rosenberg et al. retrospectively reviewed the cases of 232 children with cholesteatoma (244 ears) in an attempt to identify factors which might contribute to residual-recurrent cholesteatoma. In this particular study, approximately 2/3 of the cases initially required a mastoidectomy for management. The authors found that residual-recurrent cholesteatoma was associated with the presence of ossicular erosion but not the approach used. The rate of residual-recurrent disease was highest in the first 3 postsurgical years and reached 61% at 6 years. The aggressive nature of cholesteatoma in children was reinforced, and diligent long-term follow-up was recommended including the necessity of a second-look procedure in those children demonstrating ossicular erosion.

Although there has been no consensus as to the most appropriate surgical approach for the optimal surgical management of cholesteatoma, most studies in the literature demonstate a higher degree of recidivistic disease in cases treated with an intact canal wall approach. Nevertheless, strong proponents of both intact canal wall and canal wall down mastoidectomy continue to argue their reasoning for the use of a particular procedure. Two studies, each representing a different side of the controversy, are Dodson et al. at the University of Virginia and Hirsch et al. at the University of Pittsburgh.

Dodson et al. retrospectively reviewed the cases of 66 pediatric patients with cholesteatoma (73 ears) followed for an average of 37.7 months. Recidivistic disease

was noted in 41% of the patients having intact canal wall mastoidectomy compared with 12% recidivism in those having a canal wall down procedure. Hearing results were comparable for the two procedures with a postoperative speech reception threshold of less than 30 dB in 75% of cases with intact canal wall and 72% of cases with canal wall down. With a planned second-stage procedure, the authors feel that an ear with no mastoid cavity to maintain and good hearing is the preferable method to attempt initial eradication of cholesteatoma unless this approach is precluded for other reasons (i.e. presence of labyrinthine fistula).

Conversely, Hirsch et al. favor the canal wall down approach for removal of cholesteatoma in children. These authors retrospectively reviewed 164 cases of pediatric cholesteatoma, 116 of which were available for a 5 year follow-up period. The majority of the patients required a canal wall down procedure including modified radical mastoidectomy and radical mastoidectomy. Rates of recidivistic disease were 11% for tympanoplasty, 19% for intact canal wall mastoidectomy, 5% for modified radical mastoidectomy, and 0% for radical mastoidectomy. They also reported a need for fewer revisions with canal wall down surgery and better hearing results with this approach in their review.

Complications

Conductive hearing loss is probably the most common complication of cholesteatoma and may result from ossicular erosion or mass effect. One or more ossicles may be involved, and the lenticular process of the incus is often cited as the most common site of erosion. The degree of conductive hearing loss varies considerably depending on the situation at hand. A maximal conductive loss may be evident with erosion the lenticular process of the incus and the stapes superstructure. On the other hand, hearing loss may be minimal with severe retraction resulting in creation of a myringostapediopexy or with transmission of sound directly through cholesteatoma to the stapes. The ossicular chain should always be assumed to be intact until careful inspection and palpation at operation prove otherwise. Cholesteatoma in the vicinity of the stapes superstructure and footplate should always be addressed last and removed with great care. Evidence of sensorineural hearing loss should prompt suspicion of possible involvement of the labyrinth.

Labyrinthine fistula should be suspected in patients with sensorineural hearing loss or vestibular symptoms. The labyrinth or basal turn of the cochlea may be involved. The lateral semicircular canal is the most common site of fistula formation and is the first area encountered by the advancing cholesteatoma as the disease process extends through the antrum. Management of the cholesteatoma matrix covering the fistula site varies, and this area should be addressed last during the procedure. In an only-hearing ear, the matrix should be left intact over the fistula. Matrix should also be left intact over extensive fistulae involving the vestibule or cochlea in an ear with normal hearing. On the other hand, in a relatively dry, uninfected ear with normal hearing in the opposite ear, the surgeon may elect to remove the matrix over a small fistula of the semicircular canal and cover the fistula site with fascia or bone pate.

Facial nerve paresis or paralysis may occur with extensive cholesteatoma or supervening infection and requires immediate surgical intervention. The approach is planned based on the most likely site of involvement as evidenced by computed tomography of the temporal bone. Removal of cholesteatoma and infected material with decompression of the nerve is usually sufficient in conjunction with the administration of intravenous antibiotics. Steroids may also be helpful. Involvement of the facial nerve by cholesteatoma is said to be most likely to occur in the area of the geniculate ganglion from disease in the anterior epitympanum.

The tympanic segment of the facial nerve is a common site of iatrogenic injury both during mastoidectomy and removal of cholesteatoma from the middle ear. A dehiscence in the fallopian canal may be present as a normal anatomical variant or as a result of disease. Immediate repair is performed if the injury is apparent intraoperatively. Immediate, complete postoperative facial nerve paralysis in which the facial nerve was identified and noted to be intact intraoperatively may be managed expectantly with serial electroneuronography. Recovery may be expected. Infiltration of local anesthetic solution in the vicinity of the anterior cartilaginous external auditory canal may result in paralysis, and, under circumstances similar to those noted above, may be expected to recover within several hours. Timely re-exploration is required in instances in which integrity of the nerve is questionable. Delayed, complete postoperative paralysis occurring less than 3 days after surgery is typically the result of minor trauma with an intact nerve, and edema is the likely etiology. Again, management is expectant with serial electroneuronography, and full recovery may be expected. However, viral reactivation with varicella zoster virus should be considered in those cases in which the delayed, completed paralysis occurs 5 or more days after surgery, and anti-virals may be helpful.

Intratemporal or intracranial complications of cholesteatoma are serious and may be life-threatening. Expeditious evaluation and management are mandatory.

Infection with resultant chronic suppurative otitis media is often associated with the presence of a cholesteatoma, and serious neurotologic sequelae may result. The clinician must maintain a high index of suspicion to afford early recognition of these serious complications with the prompt initiation of appropriate management. The clinical picture may be clouded by prior antibiotic and/or otologic surgical therapy.

Early findings which may suggest an impending complication typically includes suppurative, malodorous otorrhea. The otorrhea is usually chronic or recurrent. Headache, pain, and fever are other early findings. Systemic signs and symptoms may initially be subtle but should not be overlooked. The onset of vestibular symptoms may suggest a suppurative labyrinthitis. Squamous debris from cholesteatoma and/or granulation tissue are usually noted on the physical examination.

The presence of mental status changes are consistent with intracranial extension of the inflammatory process, and nuchal rigidity and cranial nerve involvement are other late findings. Epidural abscess and granulation are probably the most common abnormalities evident at surgery. Subdural empyema, meningitis, and cerebral abscess are other possibilites. Intracranial complications warrant neurosurgical consultation with urgent or emergent intervention prior to definitively addressing the otologic component of the disease process.

Encephalocele may occur as a result of iatrogenic dural exposure and disruption in the area of the tegmen tympani or mastoideum. Leakage of cerebrospinal fluid may or may not be evident. When recognized at the initial procedure, the dural defect should be repaired with temporalis fascia or similar material. Cartilage may be necessary to provide support for larger defects. Leakage of CSF may necessitate placement of a lumbar drain for management. Should an encephalocele develop and be noted at a subsequent procedure, the non-viable, herniated tissue should be removed at the level of the dura for biopsy and confirmation and the defect repaired.

Conclusions

 


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