eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > Middle Ear & Mastoid

Middle Ear, Cholesteatoma

Peter S Roland, MD, Professor, Department of Neurological Surgery, Professor and Chairman, Department of Otolaryngology-Head and Neck Surgery, Director of Clinical Center for Auditory, Vestibular and Facial Nerve Disorders, Chief of Pediatric Otology, University of Texas Southwestern Medical Center; Adjunct Professor of Communicative Disorders, University of Texas School of Human Development

Updated: Jun 29, 2009

Introduction

Cholesteatomas have been recognized for decades as a destructive lesion of the skull base that can erode and destroy important structures within the temporal bone. Its potential for causing central nervous system complications (eg, brain abscess, meningitis) makes it a potentially fatal lesion.

Middle ear cholesteatoma. Attic cholesteatoma. This is a typical primary acquired cholesteatoma in its earliest stages.

History of the Procedure

Cholesteatomas were first described in 1829 by Cruveilhier, but Muller first named them in 1858. Throughout the early half of the 20th century, cholesteatomas were managed by exteriorization. The mastoid air cells were exenterated, the posterior external auditory canal removed, and the ear canal opening into the resulting cavity enlarged to ensure adequate air exchange and to make visual inspection simple.

In the 1950s and 1960s, a new approach was promulgated by William and Howard House's Otologic Medical Group (currently the House Ear Clinic). The surgical anatomy of the facial recess was described and clarified by William House, MD, the great pioneering otologist of the 20th century. Operating through the facial recess permitted access to the middle ear through the mastoid without removing the posterior canal wall.

By operating through the facial recess, cholesteatoma could be removed without taking down the posterior canal wall. Over time, more and more surgeons attempted to leave the basic underlying anatomic structure of the ear and temporal bone intact by preserving the canal wall. These aggressive attempts to conserve the normal anatomy of the ear created great controversy. Surgeons tended to align themselves with either the old canal-wall-down or with the new canal-wall-up philosophies.

Over the last couple of decades, most otologic surgeons have migrated to an intermediate position. Most otologic surgeons in the United States now perform both techniques, selecting one or the other of these operations depending on the individual circumstances of a particular patient.

Problem

A cholesteatoma consists of squamous epithelium that is trapped within the skull base. Squamous epithelium trapped within the temporal bone, middle ear, or mastoid can expand only at the expense of the bone that surrounds and contains it. Consequently, the complications associated with a growing cholesteatoma include injury to any of the structures normally found within the temporal bone. Occasionally, cholesteatomas escape the confines of the temporal bone and skull base. Extratemporal complications may occur in the neck, central nervous system, or both. Cholesteatomas sometimes become large enough to distort normal brain and produce brain dysfunction from mass effects.

Bony erosion occurs by 2 principal mechanisms. First, pressure effects produce bony remodeling, as occurs normally throughout the entire skeleton when pressure is applied consistently over time. Second, enzymatic activity at the margin of the cholesteatoma enhances osteoclastic activity, which greatly increases the speed of bone resorption. The level of these osteolytic enzymes appears to increase when a cholesteatoma becomes infected.¹

Frequency

The incidence of cholesteatomas is unknown, but it is a relatively common reason for otologic surgery (approximately weekly in tertiary otologic practices). Death from intracranial complications of a cholesteatoma is now uncommon, which is attributable to earlier recognition, timely surgical intervention, and supportive antibiotic therapy. Cholesteatomas remain a relatively common cause of permanent, moderate conductive hearing loss in children and adults.

Etiology

Generally, 3 separate types of cholesteatomas are identified based on different etiologies: congenital, primary acquired, and secondary acquired. The evolution of these 3 different types of cholesteatomas is described in the section below on pathophysiology.

Pathophysiology

Congenital

Congenital cholesteatomas arise as a consequence of squamous epithelium trapped within the temporal bone during embryogenesis. The typical congenital cholesteatoma is found in the anterior mesotympanum or in the perieustachian tube area. They are identified most commonly in early childhood (6 mo to 5 y).

As they expand, they can obstruct the eustachian tube and produce chronic middle ear fluid and conductive hearing loss. They can also expand posteriorly to encase the ossicular chain and, by this mechanism, produce conductive hearing loss. Unlike other forms of cholesteatoma, congenital cholesteatomas are usually identified most commonly behind an intact and normal-appearing tympanic membrane. The child often has no history of recurrent suppurative ear disease, previous otologic surgery, or tympanic membrane perforation.²

Primary acquired

Primary acquired cholesteatomas arise as the result of tympanic membrane retraction. The classic primary acquired cholesteatoma develops from progressively deeper medial retraction of the pars flaccida into the epitympanum. As this process continues, the lateral wall of the epitympanum (called the scutum) is slowly eroded, producing a defect in the lateral wall of the epitympanum that slowly expands. The tympanic membrane continues retracting medially until it passes over the heads of the ossicles and into the posterior epitympanum. Ossicular destruction is common. If the cholesteatoma pokes posteriorly into the aditus ad antrum and the mastoid itself, erosion of the tegmen mastoideum, with exposure of the dura and/or erosion of the lateral semicircular canal with deafness and vertigo, may result.³

A second type of primary acquired cholesteatomas arises when the posterior quadrant of the tympanic membrane is retracted into the posterior middle ear. The drum initially adheres to the long process of the incus. As retraction continues medially and posteriorly, squamous epithelium envelops the superstructure of the stapes and retracts into the sinus tympani. Primary cholesteatomas arising from the posterior tympanic membrane are likely to produce facial nerve exposure (and occasionally paralysis) and destruction of the stapedial superstructure. Surgical removal from the sinus tympani may be extremely challenging.

Secondary acquired

Secondary acquired cholesteatomas occur as a direct consequence of some type of injury to the tympanic membrane. This injury can be a perforation that has arisen as a result of acute otitis media or trauma, or it may be due to surgical manipulation of the drum. A procedure as simple as the insertion of tympanostomy tubes could implant squamous epithelium into the middle ear, ultimately producing a cholesteatoma. Posterior marginal perforations are the most likely to result in cholesteatoma formation. Although central perforations are considered unlikely to produce cholesteatomas, central perforations occasionally result in cholesteatoma formation. Any deep retraction pocket can result in cholesteatoma formation if the retraction pocket becomes deep enough to trap desquamated epithelium.⁴

Presentation

The hallmark symptom of a cholesteatoma is painless otorrhea, either unremitting or frequently recurrent. When the cholesteatoma becomes infected, the infection may be extremely difficult to eradicate. Because the cholesteatoma has no blood supply, systemic antibiotics cannot be delivered to the center of the cholesteatoma. Topical antibiotics often surround a cholesteatoma, suppress infection, and penetrate a few millimeters toward its center; however, a large, infected cholesteatoma is resistant to any type of antimicrobial therapy. Consequently, otorrhea either persists or recurs, despite frequent and aggressive treatment with antibiotics.

Hearing loss is also a common symptom of cholesteatomas. Large cholesteatomas fill the middle ear space with desquamated epithelium, with or without associated mucopurulent discharge. Ossicular damage is frequently present and can produce or magnify a conductive loss.

Dizziness is a relatively uncommon symptom of cholesteatomas, but it does occur if bony erosion produces a labyrinthine fistula or if the cholesteatoma is lying directly on the footplate of the stapes. Dizziness is a worrisome symptom because it may presage the development of more serious complications.

Upon physical examination, the most common sign of a cholesteatoma is drainage and granulation tissue in the ear canal and middle ear unresponsive to antimicrobial therapy. A tympanic membrane perforation is present in more than 90% of cases. Congenital cholesteatomas are an exception and the drum often remains intact until the middle ear component is quite large. Occasionally, a cholesteatoma that is produced by surgical implantation of squamous epithelium manifests prior to disruption of the tympanic membrane, but even in such cases, the cholesteatoma eventually produces a tympanic membrane perforation.⁵

Quite frequently, the only finding upon physical examination is a canal filled with mucopus and granulation tissue. Sometimes eliminating the infection and resolving the granulation tissue with either systemic antibiotics or ototopical antibiotic drops is impossible. When ototopical therapy is successful, a deep tympanic retraction pocket may be seen in the pars flaccida or posterior quadrant.

Very seldom is a cholesteatoma first identified based on one of its complications; however, this occasionally happens in children. An infection associated with the cholesteatoma can erupt through the inferior mastoid cortex and manifest as an abscess in the neck. Occasionally, cholesteatomas first manifest with the signs and symptoms of central nervous complications: sigmoid sinus thrombosis, epidural abscess, or meningitis.

Indications

Virtually all cholesteatomas should be excised. Occasional exceptions include the patient whose general health is so poor that it makes a surgical procedure too risky. Some patients who have cholesteatomas in their only hearing ear are, with good reason, reluctant to undergo surgery. The risks of profound hearing loss from surgical removal are generally less than the risk associated with leaving the cholesteatoma in situ.

Contraindications

The only absolute contraindications to the surgical removal of cholesteatomas are medical in nature. Some individuals have health problems of such gravity as to make the risk of surgical intervention unacceptably high.

Absence of hearing in the contralateral ear is a relative contraindication to surgery. Frequently, the cholesteatoma presents a greater risk to residual hearing than surgery, and, more often than not, surgical removal is the management option of choice even when the cholesteatoma is in the only hearing ear.

Workup

Imaging Studies

• CT scanning is the imaging modality of choice because CT scanning can detect subtle bony defects. However, CT scanning cannot always distinguish between granulation tissue and a cholesteatoma. Even technically excellent fine-cut CT scans cannot reliably determine the full extent of disease. The surgeon cannot always predict what is needed in the operating room based on findings from the preoperative evaluation. Both the operating surgeon and the patient must understand this limitation of the preoperative assessment and be prepared for intraoperative surprises.^6,7,8 Gaurano (2004) has demonstrated that expansion of the mastoid antrum can be seen in 92% of middle ear cholesteatomas and, similarly, 92% had CT demonstrable erosion of the ossicles.The subtle bony defects that can be detected using CT a scan include the following:⁸
  • Scutal erosion
  • Labyrinthine fistula
  • Defects in the tegmen
  • Details of ossicular involvement
  • Details of ossicular erosion or discontinuity
  • Anomalies or invasion of the fallopian canal
• MRI is used when very specific problems are expected to involve surrounding soft tissues. These problems including the following:⁸
  • Dural involvement or invasion
  • Subdural or epidural abscess
  • Herniated brain into the mastoid cavity
  • Inflammation of the membranous labyrinth or facial nerve
  • Sigmoid sinus thrombosis
• A number of articles have recently appeared in the literature suggesting that diffusion weighted MRI may be able to distinguish between recurrent or persistent middle ear cholesteatoma and scar tissue or granulation tissue. If future studies verify both a high sensitivity and specificity, replacing routine second look procedures with high quality diffusion weighted MRI images may be possible.^9,10
• Some surgeons reserve preoperative imaging for only special cases and are quite comfortable performing surgery without it. These surgeons may request a preoperative CT scan in the following circumstances:
  • If the diagnosis is in doubt: The diagnosis may be in doubt in individuals with only small attic retractions observed during the physical examination. CT scanning may help distinguish between shallow retractions without soft tissue extension into the epitympanic space and an extensive soft tissue mass with bony erosion. CT scanning can be helpful in individuals who have already had tympanomastoid surgery. In this group of patients, a white mass behind the tympanic membrane could represent tympanosclerosis, cartilage, or a recurrent cholesteatoma. CT scan findings frequently help resolve such questions. Diffusion weighted MRI may also be helpful in such circumstances.
  • If the patient is adamant about avoiding an operation: Poor surgical candidates or patients who wish to avoid an operation for other reasons can be better advised about the risks of nonsurgical management if a CT has been performed and findings are evaluated. The presence of extensive disease, labyrinthine fistula, encroachment on the fallopian canal, and involvement of the oval window niche increase the risk of expectant management.
  • Helping a patient or parents assess some of the risks of ossicular involvement is often useful: If ossicular involvement is apparent on preoperative CT scans, parents should be counseled that ossicular removal may be necessary and significant postoperative conductive hearing loss should be expected.
  • If the underlying anatomy is indeterminate and the extent of disease is unclear as the result of previous surgery
  • In patients with congenital anomalies (eg, atresia cases, individuals with craniofacial anomalies)
  • If complications are suspected.
  • If labyrinthine fistula or erosion of the fallopian canal is suspected: In this case, CT scanning remains the procedure of choice.
  • If intracranial invasion, dural inflammation, meningitis, abscess, or sigmoid sinus thrombosis is suspected, MRI is indicated.
• Other surgeons believe any patient with a cholesteatoma who is scheduled for surgical intervention should have a preoperative CT scan. They believe that useful information is obtained in every circumstance and, consequently, that the expense and radiation exposure is always justified.

Other Tests

Incisional biopsies are unnecessary because the diagnosis can be made based on physical examination and radiography findings.

Diagnostic Procedures

Audiometry should be performed prior to surgery whenever possible. Occasionally, a serious complication may require urgent surgery, and, in such cases, audiometric testing can be foregone. Air conduction, bone conduction, speech reception threshold, and speech discrimination scores should all be determined within a few weeks of the proposed operative procedure. No other diagnostic tests are generally necessary.

Histologic Findings

The histology findings from surgically removed cholesteatoma specimens demonstrate typical squamous epithelium. The histology is indistinguishable from that of sebaceous cysts or keratomas removed from any other portion of the body.

Treatment

Medical Therapy

Medical therapy is not a viable treatment for cholesteatomas. Patients who refuse surgery or whose medical condition makes a general anesthetic too hazardous should have their ears cleaned regularly. Regular cleaning can help control infection and may slow growth, but it does not stop further expansion and does not eliminate risk. The mainstay of microbial therapy should be topical, but systemic therapy is occasionally a helpful adjunct.

Surgical Therapy

Surgical therapy consists of removing the cholesteatoma. In certain circumstances, the surgeon can make the decision to use a canal-wall-up (closed) or canal-wall-down (open) technique preoperatively. If the patient has had several episodes of recurrence of the cholesteatoma and wishes to avoid future operations, the canal-wall-down technique is most applicable. For those who are unwilling or unable to return for a second-look procedure, a canal-wall-down operation is safer.^11,12

A large meatoplasty is simply unacceptable under any circumstances for some patients. Such patients can be treated with a closed (canal-wall-up) technique, provided they understand that disease recurrence is more likely and they may require multiple, serial surgical procedures.

A variety of factors help determine which operation is best. Sometimes, this decision is not possible until the operation has begun and a clear understanding of the extent of disease has been obtained. Canal-wall-down operations have the highest probability of permanently ridding the patient of the cholesteatoma. Canal-wall-up procedures have the advantage of maintaining a normal appearance, but they have a higher risk of persistent or recurrent cholesteatomas. The risk of recurrence is sufficiently high so that most surgeons advise an obligatory second-look tympanomastoidectomy 6 months to 1 year following the initial operation. At the time of the second look, small amounts of residual disease can frequently be removed prior to the development of either complications or massive recurrence.

No operation can be successful unless the goals of the procedure are kept clearly in mind. These goals include the following:

• To make the ear safe by eliminating the cholesteatoma and chronic infection
• To make the ear problem-free for all the usual activities of daily living, including swimming
• To conserve residual hearing
• To improve hearing when possible
• To provide an acceptable cosmetic appearance

Preoperative Details

A careful discussion of the advantages and disadvantages of canal-wall-up (closed) tympanomastoidectomies and canal-wall-down (open) procedures is useful. If a canal-wall-down procedure is considered pre-operatively, showing the patient a picture of a well-crafted meatoplasty can help the patient form a clear understanding of the expected postoperative appearance.

Characteristics of the canal-wall-up procedure include the following:

• Normal appearance
• Hearing aids easily fit
• No routine cleaning required
• Relatively high rate of recurrent or persistent cholesteatomas
• High tolerance for water exposure
• Usually a staged procedure

Characteristics of the canal-wall-down procedure include the following:

• Enlarged meatus
• Hearing aids difficult to fit
• Annual or semiannual canal cleaning needed
• Low rate of persistent or recurrent cholesteatomas
• Occasional problem with water exposure: Dizziness may develop after exposure to water or cold air.
• Usually a single procedure

Intraoperative Details

Often, the best plan is to reserve the decision about how to manage the canal wall until the operation has begun and a better understanding of the extent of disease has emerged. Some intraoperative findings that favor a canal-wall-down, or open, technique, including the following:¹¹

• Involvement of the sinus tympani
• Involvement of the medial end of the canal wall, with the cholesteatoma wedged laterally between the heads of the ossicles in the epitympanum and medial canal wall
• Ostitis or irremovable cholesteatomas in the protubal area or hypotympanum: This situation sometimes mandates a true radical mastoidectomy.
• Large defects of the canal wall: Small defects in canal wall are readily repaired. Larger defects are harder to repair, and, frequently, the best plan is simply to convert the operation to an open-cavity technique.
• The presence of labyrinthine fistula: If the cholesteatoma matrix is left over the fistula so as not to expose it, remove the posterior wall of the external auditory canal. To do otherwise would be to trap epithelium within the mastoid cavity, which would simply result in cholesteatoma recurrence. If the cholesteatoma matrix is removed from the fistula, some surgeons are comfortable with leaving the canal wall up.

Most surgical procedures for cholesteatomas in the United States are now performed through an incision behind the ear combined with an incision in the external auditory canal, but the procedure can be performed through an extended incision starting in the ear canal. Completely remove the air cells of the mastoid. Elevate the tympanic membrane in the middle ear space, and carefully evaluate the mastoid. Remove the cholesteatoma. If ossicles are involved, they must be removed to avoid recurrence. Reconstruct the ossicular chain either at the end of the primary procedure or as part of a secondary operation. The tympanic membrane is usually reconstructed. If a canal-wall-up technique is used, replace missing bone with a cartilage graft. If a canal-wall-down procedure is selected, create a large meatoplasty to allow adequate air circulation into the cavity that arises as a consequence of removing the posterior canal wall.

Essential features of a canal-wall-up procedure include the following:¹²

• Removal of all infected air cells
• A functioning eustachian tube
• A well-maintained middle ear space
• Adequate communication between the mastoid and the middle ear space through the aditus ad antrum or a generous facial recess
• Elimination of any bony attic defect with a cartilage or bone graft

Essential features of a canal-wall-down procedure include the following:

• Removal of all air cells, including those within the retrofacial, retrolabyrinthine, and subarcuate air cell tracts
• Removal of the lateral and the posterior walls of the epitympanum so that the tegmen mastoideum and tegmen tympani become a smooth, featureless plane
• Amputation of the mastoid tip is usually advisable.
• Saucerization of the lateral margins of the cavity
• Lowering of the posterior bony external auditory wall to the level of the facial nerve
• Exteriorization of the anterior epitympanic recess by removing the cog
• Enlargement of the meatus (at least twice as large as normal) by removing conchal cartilage
• Lowering of the medial end of the external auditory canal toward the floor of the hypotympanum

Postoperative Details

Regular office visits are necessary following surgery. Some surgeons prefer to see the patient on the following day and remove the dressing themselves. Others prefer to wait 7-10 days; these surgeons allow the patient to remove the dressing at home after 12-48 hours. If nonabsorbable sutures or staples are used, they must be removed at 7-10 days. If suture or staple removal is unnecessary, some surgeons delay the first postoperative visit for as long as 2-3 weeks. Open cavities heal slowly, and 12-24 weeks are often required for full epithelialization.

Postoperative treatment regimens for canal-wall-down procedures vary considerably. For canal-wall-down procedures, the wick in the external auditory canal (EAC) is removed at the first postoperative visit, 7-10 days after surgery. Antibiotic otic drops are prescribed twice daily for 10 days.

For canal-wall-down cavities, the author prefers to fill the cavity with antibiotic ointment at the first postoperative visit (7-10 d after surgery). The first cavity cleaning occurs at the postoperative visit 2-3 weeks after the procedure. Often, the patient is asked to fill the cavity with peroxide daily, starting 1-2 weeks postoperatively, or to irrigate the cavity with an alcohol-vinegar solution. This limits the amount of superficial infection.

Frequently, granulation tissue forms in the open cavity as it heals. Granulation tissue may be helpful because it can contract the size of the cavity, resulting in a much smaller postoperative cavity than would be the case if the initial defect epithelialized. On the other hand, granulation tissue can obliterate medial portions of the cavity, including the newly grafted drum, and compromise the hearing outcome. Exuberant granulation tissues can significantly delay epithelialization.

Steroid creams, steroid-containing drops, and regular applications of gentian violet can be used to help control the development and extent of granulation tissue. Silver nitrate cautery effectively eliminates or reduces granulation tissue, but care must be taken. Silver nitrate produces a chemical burn, the depth of which is difficult to control. So extra caution must be used around delicate or sensitive structures such as the horizontal semicircular and facial nerve in order to avoid injury from the chemical burn produced by the silver nitrate. Open cavities require variable amounts of cleaning over the first 4-8 postoperative weeks. Cleaning can be accomplished regularly in an office setting every 2-3 weeks, depending on how quickly the cavity epithelializes.

Often, a superficial infection develops that can be effectively controlled using topical antibiotic drops. Occasionally, the causative organisms are predominantly gram-negative, with Pseudomonas species as the single most common pathogens, but gram-positive organisms, including Streptococcus and Staphylococcus species, account for 20-30% of recovered organisms.

Both aminoglycoside and fluoroquinolone topical preparations provide appropriate antibacterial spectra for these organisms. The complete absence of potential ototoxicity among the fluoroquinolones makes them appealing. If a nonsteroid otic preparation is desired, either ciprofloxacin (Ciloxan) or ofloxacin (Floxin Otic) are excellent choices.

If granulation tissue is present, steroid-containing drops may be preferred. In such cases, ciprofloxacin/hydrocortisone (Ciprodex) is an excellent choice. Antibacterial creams containing fluoroquinolones can also be used. Occasionally, if granulation tissue appears to be overwhelming, steroid creams alone are useful. If a superficial fungal infection or candidiasis develops, nystatin-triamcinolone (Mycolog) or clotrimazole (Mycelex) cream is usually sufficient to eradicate it.

Long-term care

An open cavity should be problem-free once it is fully healed, provided that the patient returns every 6-12 months for microscopic cleaning in the office. At the cleanings, variable amounts of desquamated epithelium and/or cerumen fill the depths of the cavity. Occasional areas of crusting may be present, behind which superficial areas of infection have developed. Usually, removing the crust and exposing these areas to circulating air is sufficient to resolve the infection. Home care may consist of regular installations of hydrogen peroxide or a one-to-one mixture of alcohol and white vinegar. Such installations may be administered daily, every other day, or weekly. The alcohol-vinegar combination is desiccating.

Because the skin of the epithelialized cavity is normal squamous epithelium, filling the cavity once or twice a month with an emollient is sometimes helpful. Baby oil or any other mineral oil product is effective. This may help soften cerumen and reduce itching. Most patients swim comfortably with an open cavity. Some develop vertigo when cold water enters the ear and stimulates the exposed horizontal semicircular canal. In such circumstances, the use of an earplug can effectively the block circulation of water over the exposed canal and eliminate vertigo. Children should be watched carefully the first several times they swim to make sure they do not develop dysequilibrium and vertigo while in the water.

Follow-up

Each patient must be monitored for many years. Recurrence can occur long after the initial surgical excision. Follow-up care should include semiannual or annual evaluations, even in patients who are asymptomatic.

Patients who have had canal-wall-down procedures may require follow-up evaluations as often as every 3 months for canal cleaning. On the other hand, some patients only need to be seen once a year. The frequency with which a patient with a canal-wall-down mastoidectomy cavity needs to be seen in order to keep the ear free of desquamated epithelium and cerumen becomes readily apparent. Patients who have had canal-wall-up operations generally need a second-look procedure 6-9 months after the original operation. Once the second-look operation is healed, regular follow-up care at intervals of 6 months to 1 year are necessary in order to identify persistence or recurrence of the cholesteatoma.

A variety of complications are possible from cholesteatomas and cholesteatoma surgery. The most feared complication is facial nerve paralysis. The incidence of permanent facial nerve injury following cholesteatoma surgery is not entirely certain, but it appears to be 1% or less. The risk probably is much less than 1% in the hands of experienced otologists who perform the operation regularly. Controversy exists (see Future and Controversies) about whether or not facial nerve monitoring is helpful in reducing the risk of postoperative facial nerve injury.

The chance of total neurosensory hearing loss associated with cholesteatoma removal is 1-2%. Cholesteatomas that produce labyrinthine fistulas or those that lie directly over the footplate are more likely to produce permanent neurosensory loss.

Many patients have an alteration in taste on the anterior ipsilateral tongue for weeks after an otologic procedure. However, this is rarely a complaint beyond a few months after surgery.

Long-term balance disturbance may occur as a consequence of labyrinthine or middle ear injury, but it is uncommon, occurring in fewer than 1% of cases.

In approximately 10-15% of cases, the graft fails resulting in a permanent tympanic membrane perforation. Such perforations can frequently be eliminated by performing a revision operation. Depending on the procedure, 5-30% of operations are unsuccessful, and cholesteatoma persistence or recurrence becomes evident at some point in the postoperative period. Persistence may manifest as early as 5-6 months, or it may be delayed for many years. Consequently, long-term follow-up is important.

Complications

Perichondritis or chondritis occurs in fewer than 1% of patients. Care should be taken at the time of surgery to minimize the amount of exposed cartilage because exposure and devascularization render it more susceptible to infection. The symptoms of perichondritis are (1) increasing pain, erythema, and edema of the skin over the involved conchal or auricular cartilage and (2) occasional fluctuance. The process is indolent and slow to develop.

Because the blood supply to cartilage is relatively sparse, perichondritis and chondritis are slow to respond to antibiotic therapy. Fluoroquinolones offer excellent coverage for these infections, achieving similar blood levels equal to those achieved with oral or IV administration. Antibiotic therapy must be continued for a minimum of 3-4 weeks; often, 6 weeks of oral antibiotic therapy is required. If fragments of devitalized cartilage become sequestered, they require operative removal. If no clinical response to antibiotic therapy occurs within 2-3 weeks or if the infection worsens during that period, consider operative drainage should be considered. Drains should be left in place for several weeks. A semicircular incision that parallels the margin of the antihelix minimizes the cosmetic impact.

Postoperative stenosis is usually a consequence of exuberant granulation tissue. It is more likely to occur when a postoperative infection is present. Principles of prevention include control of the infection and suppression of the granulation tissue. Surprisingly, the gentle pressure of the expanded packing often slowly increases the size of the canal. By keeping the packing in place for several months, a 1- to 2-mm nonfunctional medial canal can be expanded to 4-5 mm, which is large enough to conduct sound efficiently and prevent additional conductive hearing loss. If postoperative stenosis completely obliterates the cavity, revision of the cavity in an attempt to restore patency and improve hearing may be necessary. Split-thickness skin grafts limit the recurrence of postoperative stenosis.

The most dreaded complication of tympanomastoid surgery is injury to the facial nerve. Facial nerve injuries are sometimes recognized during the course of the procedure, but, other times, they are noted only after the patient has awakened in the recovery room or day surgery unit. Because even the suggestion of intraoperative facial nerve injury may produce in the surgeon in pronounced sympathetic discharge with high levels of circulating catecholamines, technical skills may be degraded and judgment impaired. Therefore, the surgeon should stop operating to assess the situation, and, if at all possible, a consultant opinion should be obtained immediately. The first step in managing a possible or recognized facial nerve injury is to decompress the nerve around the area thought to be injured. Remove bone a few millimeters proximal and distal to the damaged segment so that the injury can be clearly visualized.

Evaluation of the severity of injury is extremely difficult if the injured segment is in the middle ear, where the space in which the surgeon can operate is very limited. The horizontal semicircular canal limits exposure posteriorly and the superstructure of the stapes limits exposure anteriorly. Consequently, accurate assessment of the severity of injury is especially difficult in this area.

If more than 50% of the diameter of the nerve is deemed nonviable because it has been cut, crushed, or stretched, then resect the injured segment and re-anastomose or graft the nerve.

If a primary anastomosis can be achieved without tension, this is probably the best method of repair. However, a primary anastomosis, even with small segments of missing nerve, is possible only if the nerve can be mobilized and rerouted over a substantial portion of its length. This is not usually possible when surgery is limited to the mastoid and tympanic segment. If a primary anastomosis without tension cannot be achieved, then place an interposition graft.

If injury to the facial nerve is not recognized during the operation and the patient awakens with facial paralysis, the surgeon should wait several hours to make sure that this is not a consequence of the local anesthetic. If facial paralysis persists 3-4 hours beyond recovery from anesthesia, the packing should be removed.

If the facial nerve was clearly visualized at the time of surgery and the operating surgeon is absolutely certain that the nerve is anatomically intact, treat the injury like any other posttraumatic nerve paralysis. Begin electroneuronography testing approximately 72 hours postoperatively. If, within the first 2-3 weeks, the compound action potential on the affected side drops to less than 10% of the compound action potential on the normal side, the patient should be taken back to the operating room for exploration.

If the surgeon is not absolutely sure that the facial nerve is anatomically intact, the patient should be taken back to surgery immediately, the nerve decompressed around the area of injury, and the severity of the injury assessed. Based on such an assessment, the surgeon must decide whether or not to excise the injured segment. Once again, a consultation should be obtained if possible. Consultants should document their assessment and opinion on the chart.

Sometimes, a labyrinthine fistula is suggested based on the preoperative CT scan images; other times, a fistula is a complete surprise. Initially, the desquamated epithelium should be removed, carefully leaving the matrix over the horizontal canal. Blunt probes are used to locate the fistula by palpation. If the fistula appears superficial, the matrix is gently removed at the end of the case and the defect covered with fascia.

However, if the fistula is large and it appears that the cholesteatoma matrix is attached firmly to the membranous labyrinth itself,  leaving the matrix in position should be considered. Debate continues as to whether hearing loss is more likely if the matrix is removed. If the membranous labyrinth is opened at any point during the procedure, broad-spectrum intravenous antibiotics and steroids should both be administered immediately. Bacterial labyrinthitis and inflammation pose the biggest risk to hearing.¹⁵ Fistulas involving the oval window area should be treated according to the same principles. Violation of the vestibule itself is much more likely to produce hearing loss than violation of one of the semicircular canals.

Occasionally, a canal fistula is created during the surgical procedure. If such a fistula involves one of the semicircular canals, then it should be sealed with soft tissue (preferably fascia) and intravenous antibiotics and steroids administered. These patients are quite likely to have significant balance disturbance in the immediate postoperative period, but a significant number recover with little or no hearing loss if appropriate antibiotic therapy and steroids are provided in the postoperative period.

Persistent drainage from a canal-wall-down cavity can arise for a number of reasons. The most common cause of persistent drainage is either a sequestered air cell that continues to harbor infection or a small area of osteitis. In such cases, the cavity as a whole heals up quite well except for a small area that remains covered with granulation tissue. The only solution is to remove the involved area. If the area of osteitis is large and postoperative otorrhea has persisted for months or years, skin grafting should be considered. Skin grafts are especially useful in the cavities that have developed, on one or more occasions, mucosal (as opposed to squamous) epithelial linings. Sometimes, persistent or recurrent drainage is due to a residual cholesteatoma. Then the only viable solution is reoperation to remove residual disease.

Foreign bodies retained within the mastoid cavity or wound must if they have become the focus for inflammation or infection. The most common foreign bodies are small metal fragments that result from the burr hitting the end of the suction irrigation during surgery. Retained pieces or fragments of packing and/or shreds of cotton can similarly serve as a nidus of infection but can usually be removed in the office.

Brain herniation through the tegmen of the middle fossa has a characteristic glistening, shiny appearance. The presence of clear fluid associated with such a lesion should raise the suggestion of a brain hernia and cerebrospinal fluid leak. MRI and CT scanning can often help clarify the diagnosis preoperatively.

Options for managing a brain hernia fall into 2 basic categories: reconstruction of the mastoid cavity or obliteration of the mastoid cavity. If reconstruction is chosen, glialized brain can be removed simply by sharply excising it and any viable brain can be pushed back up into the middle cranial fossa. If the defect is large, both intradural and extradural repair of the dural defect should be considered. The second alternative is to simply obliterate the middle ear, external auditory canal, and mastoid by removing posterior canal wall, obliterating the eustachian tube, filling the defect with abdominal fat and over sewing the external canal. This is an especially appealing option if hearing is very poor in the afflicted ear. If all the squamous epithelium has been removed, obliteration ensures a safe, well-healed, problem-free ear. Maximal conductive hearing loss is unavoidable.

Outcome and Prognosis

Eliminating a cholesteatoma is almost always possible; however, multiple operations may be required. Because surgery is generally successful, complications from uncontrolled cholesteatoma growth are now relatively uncommon.

Canal-wall-down tympanomastoidectomy offers a very low rate of recurrence or persistence of a cholesteatoma. Reoperation for cholesteatomas occurs in 5% or fewer patients. This compares quite favorably to the 20-40% recurrence rates associated with closed-cavity techniques¹¹ .

Nonetheless, because the ossicular chain and/or tympanic membrane cannot always be completely restored to normal, cholesteatomas remain a relatively common cause of permanent conductive hearing loss.

Future and Controversies

Controversies

The routine use of facial nerve monitoring remains controversial. A survey of practicing otologists in 1990 showed that most experienced otologists do not believe that facial nerve monitoring is obligatory. Many experienced otologists only use it occasionally. Facial nerve monitoring requires experience and is unlikely to provide meaningful protection to an inexperienced surgeon.

On the other hand, some surgeons believe that predicting the cases in which the facial nerve is at risk is impossible and, consequently, believe monitoring should be performed in every case. These surgeons see facial nerve monitoring as a precaution, much like ECG monitoring, that may be potentially useful in any given case.

A large percentage of surgeons do not use facial nerve monitoring for all cases but, instead, monitor only selected cases. Such cases often include revision operations or situations in which the patient has had perioperative facial nerve weakness in the past or when imaging studies show facial nerve anomalies.

Future

The applicability of using small otoendoscopes as part of the surgical management of cholesteatomas is being explored. To date, they have only an adjunctive role; however, their role may expand in the future.

Multimedia

Media file 1: Middle ear cholesteatoma. Attic cholesteatoma. This is a typical primary acquired cholesteatoma in its earliest stages.

Media file 2: Middle ear cholesteatoma. A large cholesteatoma. No landmarks are visible, which typically is the case with advanced cholesteatomas.

Media file 3: Middle ear cholesteatoma. A congenital cholesteatoma. A white mass can be seen behind an intact drum.

Media file 4: Middle ear cholesteatoma. A large attic cholesteatoma that is much more advanced than the one in Image 1.

Media file 5: Middle ear cholesteatoma. CT scan of an erosive cholesteatoma. The posterior canal wall has been eroded away, and the external auditory canal has filled with cholesteatomatous debris. Surprisingly, the middle ear is relatively free of disease.

Media file 6: Middle ear cholesteatoma. A large, adequate meatoplasty. Such a meatoplasty is usually necessary to create a problem-free cavity.

References

1. Ottaviani F, Neglia CB, Berti E. Cytokines and adhesion molecules in middle ear cholesteatoma. A role in epithelial growth?. Acta Otolaryngol. 1999;119(4):462-7. [Medline].

2. De la Cruz A, Fayad JN. Detection and management of childhood cholesteatoma. Pediatr Ann. Jun 1999;28(6):370-3. [Medline].

3. Kemppainen HO, Puhakka HJ, Laippala PJ, et al. Epidemiology and aetiology of middle ear cholesteatoma. Acta Otolaryngol. 1999;119(5):568-72. [Medline].

4. Golz A, Goldenberg D, Netzer A, et al. Cholesteatomas associated with ventilation tube insertion. Arch Otolaryngol Head Neck Surg. Jul 1999;125(7):754-7. [Medline].

5. Thompson JW. Cholesteatomas. Pediatr Rev. Apr 1999;20(4):134-6. [Medline].

6. Tierney PA, Pracy P, Blaney SP, Bowdler DA. An assessment of the value of the preoperative computed tomography scans prior to otoendoscopic 'second look' in intact canal wall mastoid surgery. Clin Otolaryngol Allied Sci. Aug 1999;24(4):274-6. [Medline].

7. Gaurano JL, Joharjy IA. Middle ear cholesteatoma: characteristic CT findings in 64 patients. Ann Saudi Med. Nov-Dec 2004;24(6):442-7. [Medline].

8. Joel Swartz, H. Harnsberger. Imaging of the Temporal Bone. 3 Sub edition. New York: George Thieme Verlag; Oct 1, 1997.

9. Vercruysse JP, De Foer B, Pouillon M, et al. The value of diffusion-weighted MR imaging in the diagnosis of primary acquired and residual cholesteatoma: a surgical verified study of 100 patients. Eur Radiol. Mar 3 2006;[Medline].

10. Dubrulle F, Souillard R, Chechin D, et al. Diffusion-weighted MR imaging sequence in the detection of postoperative recurrent cholesteatoma. Radiology. Feb 2006;238(2):604-10.

11. Roland PS, Meyerhoff WL. Open-cavity tympanomastoidectomy. Otolaryngol Clin North Am. Jun 1999;32(3):525-46. [Medline].

12. Graham MD, Delap TG, Goldsmith MM. Closed tympanomastoidectomy. Otolaryngol Clin North Am. Jun 1999;32(3):547-54. [Medline].

13. Roth TN, Haeusler R. Inside-out technique cholesteatoma surgery: a retrospective long-term analysis of 604 operated ears between 1992 and 2006. Otol Neurotol. Jan 2009;30(1):59-63. [Medline].

14. Sanna M, Facharzt AA, Russo A, Lauda L, Pasanisi E, Bacciu A. Modified Bondy's technique: refinements of the surgical technique and long-term results. Otol Neurotol. Jan 2009;30(1):64-9. [Medline].

15. Busaba NY. Clinical presentation and management of labyrinthine fistula caused by chronic otitis media. Ann Otol Rhinol Laryngol. May 1999;108(5):435-9. [Medline].

Keywords

keratoma, cholesteatoma, middle ear cholesteatoma, canal-wall-down otologic surgery, canal-wall-up otologic surgery, canal-wall-down technique, canal-wall-up technique, ear lesion, ear mass, congenitally acquired cholesteatoma, primarily acquired cholesteatoma, secondarily acquired cholesteatoma, congenital cholesteatoma, primary cholesteatoma, secondary cholesteatoma, chronic middle ear fluid, conductive hearing loss, tympanic membrane retraction, tympanic membrane trauma, tympanic membrane injury, acute otitis media, AOM, OM, acute OM, tympanic membrane perforation, painless otorrhea, otorrhea, hearing loss, deafness

Contributor Information and Disclosures

Author

Peter S Roland, MD, Professor, Department of Neurological Surgery, Professor and Chairman, Department of Otolaryngology-Head and Neck Surgery, Director of Clinical Center for Auditory, Vestibular and Facial Nerve Disorders, Chief of Pediatric Otology, University of Texas Southwestern Medical Center; Adjunct Professor of Communicative Disorders, University of Texas School of Human Development
Peter S Roland, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Otolaryngic Allergy, American Academy of Otolaryngology-Head and Neck Surgery, American Auditory Society, American Laryngological Rhinological and Otological Society, American Neurotology Society, American Otological Society, North American Skull Base Society, and Society of University Otolaryngologists-Head and Neck Surgeons
Disclosure: Alcon labs Honoraria Speaking and teaching; GSK Honoraria Speaking and teaching; Advanced Bionics Honoraria Board membership; Cochlear corp Honoraria Board membership; Med El corp travel grants Consulting

Medical Editor

Jack A Shohet, MD, Associate Clinical Professor, Department of Otolaryngology-Head and Neck Surgery, University of California Irvine; Otolaryngologist, Shohet Ear Associates Medical Group, Inc
Jack A Shohet, MD is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery, American Medical Association, American Neurotology Society, American Tinnitus Association, and California Medical Association
Disclosure: Envoy Medical Consulting fee Consulting

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Gerard J Gianoli, MD, Clinical Associate Professor, Department of Otolaryngology-Head and Neck Surgery, Tulane University School of Medicine; Vice President, The Ear and Balance Institute; Chief Executive Officer, Ponchartrain Surgery Center
Gerard J Gianoli, MD is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery, American College of Surgeons, American Neurotology Society, American Otological Society, Society of University Otolaryngologists-Head and Neck Surgeons, and Triological Society
Disclosure: Nothing to disclose.

CME Editor

Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders
Christopher L Slack, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American Medical Association
Disclosure: Nothing to disclose.

Chief Editor

Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine
Arlen D Meyers, MD, MBA is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American Head and Neck Society
Disclosure: Covidien Corp Consulting fee Consulting; US Tobacco Corporation unstricted gift unknown; Axis Three Corporation Ownership interest Consulting; Omni Biosciences Ownership interest Consulting; Sentegra Ownership interest Board membership; Syndicom Ownership interest Consulting; Oxlo  Consulting; Medvoy Ownership interest Management position

The author is grateful for the expert help of Pam Henderson in the preparation of this manuscript.

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