Tympanoplasty-Undersurface Graft Technique: Postauricular Approach

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Chapter 12 Tympanoplasty—Undersurface Graft Technique

Postauricular Approach

C. Gary Jackson, David M. Kaylie, Michael E. Glasscock, III, Barry Strasnick

Videos corresponding to this chapter are available online at www.expertconsult.com.

Since the fundamental principles of tympanoplasty were first introduced by Wullstein ¹ and Zollner,² there has been great diversity in the accepted surgical techniques used for repair of the tympanic membrane. The multitude of graft materials employed is a testimony to the difficulty of middle ear reconstruction. With advanced microsurgical techniques, the state of the art has now developed to the extent that graft success rates of 90% to 97% are to be expected.³^–⁵ Two basic grafting techniques have evolved based on where the graft material is placed in relation to the drum remnant (overlay versus underlay techniques). This chapter presents a method of undersurface grafting. Detailed surgical techniques and appropriate preoperative and postoperative care are presented.

HISTORICAL ASPECTS

Modern middle ear reconstructive surgery represents a culmination of more than a century of contributions by numerous dedicated and innovative otologic surgeons. The term tympanoplasty was originally defined in 1964 by what was then known as the American Academy of Ophthalmology and Otolaryngology’s Committee on Conservation of Hearing as “an operation to eradicate disease in the middle ear and to reconstruct the hearing mechanism without mastoid surgery, with or without tympanic membrane grafting.”⁶ If a mastoid procedure is included, the term tympanoplasty with mastoidectomy is used.

The era of surgical repair of the tympanic membrane dates as far back as the 19th century. In 1853, Toynbee ⁷ described closure of a perforation of the tympanic membrane using a small rubber disk attached to a silver wire. Ten years later, Yearsley⁸ advocated placing a cotton ball over the perforation; in 1887, Blake⁹ introduced the concept of placing a thin paper patch over the membrane. The use of cautery to promote spontaneous healing of tympanic membrane perforations was introduced by Roosa in 1876¹⁰; he used silver nitrate. Later, Joynt,¹¹ Linn,¹² and Derlacki¹³ described modifications of this technique using various forms of cautery and patches. Closure of tympanic membrane perforations was considered appropriate only for dry central perforations, however. At this point, no one advocated the use of drum closure for the chronically draining ear.

It was not until 1952 that Wullstein ¹ and Zollner² revolutionized middle ear surgery by advocating reconstructive grafting of the chronically diseased ear through the use of full-thickness or split-thickness skin grafts. House and Sheehy¹⁴ and Plester¹⁵ later used canal skin, believing that it more closely resembled the squamous layer of the tympanic membrane. The overall poor success rates of these grafts and the development of iatrogenic cholesteatomas prompted the search for alternative grafting materials.

Shea ¹⁶ and Tabb,¹⁷ working independently, described the use of autogenous vein to close the tympanic membrane. Goodhill¹⁸ advocated tragal perichondrium in the mid-1960s, and tympanic membrane homografts became popular a few years later. Glasscock and House¹⁹ reported the first sizable series of homograft tympanic membrane transplants in 1968. Interest in homografts has waned, however, largely because of the fear of transmission of infectious diseases. Storrs²⁰ performed the first fascia graft in the United States. Although vein, perichondrium, and homografts still have their advocates, autogenous fascia has now become the standard by which all other grafting materials are measured.

The use of skin grafts required that the tympanic membrane perforation be repaired by laying the graft on top of the denuded drum remnant. This method of repair eventually became known as the overlay technique and was carried over to other forms of grafting material. With the use of connective tissue grafts, the graft material could be placed medial to the tympanic membrane remnant. The success of this approach eventually gave rise to the underlay technique of tympanic membrane grafting; Austin and Shea ³ reported a large series. Proponents of the underlay procedure submit that it eliminates many of the problems associated with overlay grafts, such as anterior blunting, epithelial pearl formation, and lateralization of the new drum.

In 1973, Glasscock ⁴ described an underlay grafting technique that relied on a postauricular approach. With minor modifications, this approach continues to be the preferred method of dealing with disorders of the tympanic membrane and the middle ear.

PREOPERATIVE FUNDAMENTAL PRINCIPLES

Regardless of the grafting technique chosen, the preoperative evaluation and management of a patient with a tympanic membrane perforation remain the same. A complete clinical history is obtained, and a comprehensive head and neck examination is performed. Particular attention is addressed to the nasopharynx. Otoscopic examination is performed with the aid of an operating microscope if necessary. All findings are diagrammed on the patient’s chart. All patients receive a pure tone air and bone conduction audiogram along with speech discrimination testing. Tuning fork tests should be done on all patients to confirm the audiologic findings.

FUNDAMENTALS

Traditional Objectives

As with any surgical procedure, successful outcomes result from mastery of understanding and execution of each component of the process as a whole. It is useful to distill the task of tympanoplasty into its important fundamentals.

The traditional objectives of tympanoplasty have not changed in 50 years and remain:

• Eradication of disease

• Closure of the ear by grafting

• Hearing rehabilitation

The goals, in this order of priority, allow for patient counseling and reasonable expectations.

Predisposing Conditions

Tympanoplasty is usually successful in achieving the above-listed goals in the short term. To ensure long-term success, conditions predisposing to failure must be prospectively managed. Generally, the status of the upper respiratory tract influences eustachian tube function and, consequently, the long-term success of tympanoplasty.

Adenoidal Hypertrophy and Adenoidectomy

Excessive adenoidal hypertrophy is regarded, by consensus, to influence the success of tympanic membrane grafting. Adenoidectomy should be done prospectively. It is generally not advised to perform adenoidectomy, with its significant effects on the nasopharynx in the short term, simultaneously with tympanic membrane grafting. After the adenoidectomy is performed, the tympanic membrane grafting is scheduled as a separate procedure, approximately 4 weeks later. Tonsillectomy is performed as an independently indicated consideration. Its effect on tympanoplasty is negligible. The clinical setting in which this occurs is generally in children younger than 10 years.

Nasal or Sinus Condition

Allergy

Allergic disease is an inexorable detriment to the long-term success of tympanic membrane grafting. In endemic areas, it should not be disregarded. At some time in the perioperative period, the tympanoplasty patient is referred for comprehensive allergy diagnosis and management. Immunotherapy, when indicated, can have a tremendous influence on long-term outcomes. Acute exacerbations, often seasonal, are managed pharmacologically with antihistamines and nasal steroids.

Rare Disorders

Particularly in recidivistic disease, the presence of rare associated diseases must be kept in mind. Tuberculosis, sarcoidosis, diabetes mellitus, hematologic disorders, histiocytoses, immunodeficiency syndromes, and, in recurrent adult disease, neoplasms should not be disregarded.

PREOPERATIVE PREPARATION

Otorrhea

Every attempt is made to operate on dry ears. Preoperative infection control in the involved ear is useful, but not essential. At the initial evaluation, the draining ear is otomicroscopically evacuated. Instructions are given to begin the instillation of steroid-containing antibiotic drops. Irrigating the ear with sterile 1.5% acetic acid solution can be helpful in eradicating recalcitrant infections. Instillation of drops in the infected ear affords minimal ototoxicity risk. Pain on administration constitutes an end point. Associated disorders or unusually significant infection may rarely warrant oral antibiotics. In the absence of any immunocompromising accompaniment, cultures are not routinely done. The physician must be vigilant for signs and symptoms of intratemporal or extratemporal complications. Surgery is scheduled, and the ear is operated on, draining or not.

Eustachian Tubal Tests

No clinical test exists for eustachian tubal physiology. Eustachian tubal patency is testable via methods such as the Valsalva maneuver and the Toynbee test, but it is not important in the grand schematic of tympanoplasty. Eustachian tubal physiology tests exist (e.g., the Flisberg test), but are clinically impractical and are not done. A statement attributed to Sheehy is true: “Sometimes the best test of eustachian tubal function is a tympanoplasty.”

Eustachian tube function is nonetheless important to tympanic membrane grafting success. Status of the contralateral ear often predicts the eustachian tubal capacity of the involved ear. Apparent current eustachian tubal dysfunction may be a consequence of active infections unilaterally or the aftermath of a lifetime of chronic otitis media. Tympanoplasty is not contraindicated. Postoperatively, when the ear is restored to a more normal state, its eustachian tubal function may also be restored. In the difficult situation of tracheostomy in which eustachian tube function is compromised or when effusion or retraction affects the successful graft, the ear can be ventilated in the office. Ventilation tubes should not be placed in tympanic membrane grafts because they promptly extrude. Tube placement can be performed in the first month after the procedure in the office because the tympanic membrane is still anesthetic.

An atelectatic ear should not preclude tympanoplasty. Rather, it is a perfect indication for cartilage tympanoplasty.

Imaging

The imaging standard for chronic otitis media is now high-resolution temporal bone computed tomography (CT). Contrast medium is also employed to evaluate clinically silent epidural, intracranial, or lateral sinus abscess. Plain mastoid radiographs have been abandoned, as has polytomography. All ears for grafting are not imaged. Only hearing ears and disease in long-standing adult chronic otitis media are ideal candidates. It is prudent to obtain CT scans for revision surgery, particularly if the initial surgery was done by another surgeon. Selected cholesteatomas may be studied, although imaging is unnecessary for all cholesteatomas. Patients with a cholesteatoma in which an inner ear fistula or tegmen defect with encephalocele is suspected are good candidates for imaging. The current state of magnetic resonance imaging (MRI) precludes its routine use in ear imaging of chronic otitis media. Magnetic resonance angiography is useful in venous phase to assess the lateral venous sinus.

Complications

Polypharmacy and accessible medical care have changed the face of diagnosis of temporal bone and intracranial complications in chronic otitis media. Pain, focal neurology, headache, vertigo, particularly noisome (anaerobic) otorrhea, cephalgia, and sensorineural hearing loss all should elicit the applicable cliché: “high index of suspicion.”

Informed Consent

Preoperative counseling regarding the nature and extent of the problem, treatment options, surgical details, surgical staging, reasonable expectations, and risks and complications is comprehensive. This discussion is interpersonal and reviewed in professionally prepared videotapes. The consent and preoperative and postoperative instructions are provided in written form, and the patient is asked to sign the informed consent in the presence of a neutral witness. Common complications discussed include, but are not limited to, hearing loss, infection, graft failure, and facial nerve paralysis. Disorder-focused brochures are also given to the patient.

BASIC TECHNICAL PRINCIPLES

The basic surgical principles we all learn as surgical interns are as important here as ever when the operating microscope is introduced as a surgical tool.

Infection Control

Chronic ear surgery is clean-contaminated or contaminated; 90% of otologic wounds are colonized at the time of surgery. The general surgical principle of infection control seeks to minimize colony counts so that host defense mechanisms are not overwhelmed. Whether or not surgeons can accomplish this in ear surgery is highly debated. Otologists seeking higher graft take rates and fewer complications often resort to prophylactic antibiotics as a “protective umbrella.”

In the only study of statistical power on this subject, Jackson ²³ concluded that prophylactic antibiotics are harmless, but useless. In common uncomplicated tympanoplasty, antimicrobial prophylaxis is unwarranted. An indication for prophylaxis exists in the draining ear, which, intuitively, has a high postinfection rate with graft failure. Despite this fact, no protocol exists to prevent such an outcome. This is an ideal indication for intraoperative irrigation, yet ototoxicity and medicolegal concerns have impeded human study design to address this issue.

There are indications for antimicrobial prophylaxis in ear surgery. Violation of the dural integrity with or without cerebrospinal fluid leakage, violation of the labyrinth, acknowledged aseptic technique breaks, only hearing ears, and implantation of indwelling devices such as cochlear implants all are valid indications.

“The secret to pollution is dilution.” Aggressive irrigation throughout the procedure theoretically clears devitalized debris and clots, and is thought to reduce colony counts. Normal saline is used. The surgical preparation is described in the section on technique.

Hemostasis

Prior injection of the surgical field with 2% lidocaine (Xylocaine) and 1:100,000 epinephrine helps reduce bleeding in the surgical field, which is essential to microsurgery. These solutions are contained in dental carpules so that loose solutions with their attendant risks are not on the surgical table to be confused. Electromicrobipolar cautery, adapted from neurotology, is useful in eliminating bleeding from the lateral venous sinus, dura, facial nerve, and delicate external auditory canal (EAC) flaps.

Excessive bleeding from infected areas granulating can be difficult. Absorbable gelatin sponge (Gelfoam) soaked in 1:100,000 epinephrine placed on the involved site while surgical attention is directed elsewhere is efficient hemostasis. Aggressive irrigation is thought to help control blood loss and affect hemostasis. Graft placement of any kind cannot be efficient under water. A bloodless field to identify all margins is essential. While preparing the graft, the operative field is filled with epinephrine-soaked Gelfoam until graft placement is imminent.

Grafting Techniques and Exposure

Two approaches to tympanic membrane grafting have evolved over the years. The overlay technique previously was popular because of its high success rate and reproducibility.²⁴ Experience has recognized recurring downsides, however. Blunting of the anterior sulcus, when significant, can result in conductive hearing loss by malleus fixation, as can lateralization of the graft away from the malleus. Inability to denude the drum of epithelium completely could and has resulted in epithelial pearls or cholesteatoma or both. Because the EAC skin is removed and replaced, delays in healing occur.

The undersurface graft placement technique has been propelled by the adoption of connective tissue as a grafting material. Because this surgery was commonly performed with a transcanal approach through a speculum, underlay grafting was regarded as more technically difficult. Irregular graft placement—hence failure—often resulted. Variations in size and contour of the EAC and operator experience using a speculum impaired visualization of the entire tympanic membrane remnant and anterior sulcus, making graft placement particularly challenging. Adequate exposure of the middle ear and eustachian tubal orifice was rare.

The postauricular approach obviated all of these problems using the vascular strip access. Anterior EAC wall bulges could be easily managed, and no speculum was needed. Overall exposure was enhanced, allowing luxurious middle ear exposure and precise graft placement. All the complications of the overlay strategy are avoided. For the experienced ear surgeon, either placement strategy produces the desired outcome in greater than 90% of grafts. For some ear surgeons, the postauricular undersurface technique affords higher take rates with fewer complications.

Mastoidectomy

Tympanic membrane perforation with cholesteatoma virtually mandates performing a mastoidectomy. Data do not exist to guide the ear surgeon regarding performing mastoidectomy or not when tympanic membrane perforation exists. In uncomplicated tympanic membrane rupture, such as in trauma, mastoidectomy is rarely indicated.

Tympanic membrane grafts fail most commonly because of infection in the middle ear or mastoid. We readily assess and manage middle ear infection at the time of tympanoplasty. In any suggestion of mastoid infection, recent otorrhea, refractory or recurrent disease, or difficult aeration occasions such as tracheostomy, if it seems appropriate, mastoidectomy is executed.

Ossicular Reconstruction

The key to successful ossicular reconstruction is understanding the healing concept of changing anatomic relationships. When anatomic relationships in the middle ear are minimal or stabilized, ossicular reconstruction is unstaged. When anatomic relationships are expected to change, such as in the most diseased ears because of complicated tympanic membrane pathology, extensive mucosal disease, extensive ossicular pathology, a fixed footplate, or extensive tympanosclerosis or healing biology, ossicular reconstruction is staged.

Autogenous cartilage is always interposed between platforms and tympanic membrane graft undersurfaces. Cartilage is not interposed for hydroxyapatite. If possible, autogenous material is preferred.

Facial Nerve Monitoring

Neural integrity monitoring of the facial nerve is used for all otologic cases. Paralyzing agents are not used in ear surgery anesthesia. Nerve monitoring informs technique relative to the facial nerve. Monitoring is no substitute for knowledge of the anatomy, sound tissue technique, or surgical instinct.

SURGICAL TECHNIQUE

Surgical Preparation

A 2-cm wide area of hair is shaved above and behind the auricle, and Mastisol is placed. Nonsterile 3M (No. 1010) plastic towel drapes are placed on the skin to cover the hair. Electrode insertion for intraoperative facial nerve monitoring occurs before the surgical preparation. An iodine soap solution is used to wash the auricle and the skin around it, which is blotted dry with a sterile towel. The ear itself is bathed in an iodine preparation solution for 3 minutes. The solution is allowed to enter the EAC. Finally, the area around the ear is prepared with an alcohol-based solution (DuraPrep Surgical Solution).

The postauricular region and the tragus are injected with a 2% lidocaine and 1:100,000 epinephrine solution. After injection, the patient is draped with two layers of sterile sheets. The first layer consists of a 3M plastic ear drape (No. 1030). This waterproof sheet effectively isolates the patient and prevents contamination if the paper drapes become soaked with irrigation solution. Finally, a custom-designed paper otologic drape and a plastic drainage bag are applied (Fig. 12-1). Suction-irrigation tubing and cautery lines are secured to the field. The scrub nurse attaches a compartmentalized plastic pouch to the Mayo stand to hold suction tips and electrocauteries.

FIGURE 12-1 The ear and postauricular area are prepared and draped in a sterile fashion.

Anesthesia

All patients undergo general endotracheal anesthesia with an epinephrine-compatible anesthetic agent. Long circuits are used on the anesthesia machine to enable the anesthesiologist to be seated at the foot of the table, opposite the surgeon (Fig. 12-2). The scrub nurse is positioned at the head of the table across from the surgeon.

FIGURE 12-2 Operating room arrangement. The scrub nurse is located directly across from the surgeon, and the anesthesiologist (not shown) is seated at the foot of the table.

The vascular strip and four quadrants of the ear canal are injected with the 2% lidocaine and 1:100,000 epinephrine solution. The local anesthetic reduces pain and allows the patient to be kept relatively “light” during the procedure. No limitations on the use of nitrous oxide during graft placement are required because the undersurface placement of the graft, along with packing of the eustachian tube orifice, precludes the graft being elevated off the drum remnant. The nitrous oxide bubbles escape harmlessly up the posterior canal wall.

Every attempt is made to extubate the patient deeply to avoid straining and potentially detrimental Valsalva efforts. Intravenous antiemetics are given to reduce postsurgical nausea and vomiting.

Incisions

The vascular strip is outlined by making incisions at the tympanosquamous and tympanomastoid suture lines using a No. 67 Beaver knife blade. In addition, small inferiorly and superiorly based flaps are created by making right angle incisions to the vascular strip incisions. The medial end of the vascular strip is formed by connecting the two primary incisions with a No. 72 Beaver blade approximately 2 mm lateral to the annulus (Fig. 12-3).

FIGURE 12-3 Vascular strip is outlined with No. 67 and No. 72 Beaver blade.

FIGURE 12-4. Standard postauricular incision is fashioned approximately 5 mm behind the postauricular crease.

FIGURE 12-5. A, The loose areolar tissue overlying the temporalis fascia is harvested as a free graft. Note T-incision through the mastoid periosteum used to expose the external auditory canal. B, The vascular strip is held forward along with the auricle.

FIGURE 12-6. A, The inferior canal flap is elevated to the level of the fibrous annulus. B, The malleus is denuded, and the undersurface of the drum remnant or annulus is abraded, while diseased mucosa is removed.

FIGURE 12-7. A, The fascia graft is directed under the fibrous annulus and malleus handle. B, The superior and inferior canal flaps are replaced over the fascia graft.

A postauricular incision is made approximately 5 mm behind the postauricular crease (Fig. 12-4). The surgeon firmly grasps the auricle in the left hand and forcefully pulls forward and outward. Constant tension allows identification of the loose areolar tissue overlying the temporalis fascia and creates a bloodless surgical plane. Incisional bleeding is controlled with electric cautery.

Harvesting Fascia

When hemostasis is achieved, a small Weitlaner retractor is positioned to hold the auricle forward. The scrub nurse places a small Senn retractor under the upper part of the incision and pulls laterally, exposing the temporalis fascia. The loose areolar tissue overlying the temporalis fascia is ballooned up with a local anesthetic to facilitate its removal. An incision is made at the level of the linea temporalis, and the areolar tissue is dissected free from the temporalis fascia using Metzenbaum scissors (Fig. 12-5). This tissue is pressed onto a polytef (Teflon) block and placed on the back table under a gooseneck lamp to dehydrate it.

Exposing the Middle Ear

The retractor is removed, and an incision is made along the linea temporalis extending anterior and superior to the EAC. A T-shaped incision is created by dropping a vertical limb from the midpoint of the linea temporalis to the mastoid tip (see Fig. 12-5). A Lempert elevator is used to mobilize the periosteum to the level of the ear canal. The vascular strip is identified from posteriorly, grasped with Adson forceps, and held forward in the blade of a Weitlaner retractor along with the auricle (see Fig. 12-5). A second Weitlaner retractor is placed between the temporalis muscle and the mastoid tip at right angles to the first retractor.

The ear canal is copiously irrigated with a physiologic saline solution to remove blood debris. With a 20 gauge needle suction in the surgeon’s left hand and a House No. 2 lancet knife in his or her right hand, the skin of the inferior ear canal is elevated down to the fibrous annulus (Fig. 12-6), creating an inferiorly based flap. Next, a House No. 1 sickle knife is used to develop a superior flap just above the short process of the malleus. The fibrous annulus is mobilized out of its sulcus anterior to the malleus.

If the operating table is rotated away from the surgeon, the anterior drum remnant and annulus are easily seen. If a bony overhang obscures complete vision, the canal skin can be reflected laterally, the bone removed with a small diamond burr, and the skin reflected downward. Care must be taken to protect the anterior annulus and adjacent canal skin.

Eradication of Disease

With the middle ear now well exposed, the primary disease process can be addressed logically. Cholesteatoma, granulation tissue, or polypoid disease can be removed through the middle ear itself or in conjunction with a mastoidectomy if indicated. For better exposure of the middle ear, the facial recess or posterior tympanotomy is opened, leaving the posterior canal wall intact.

Preparation of the Tympanic Membrane Remnant

When the disease of the middle ear and mastoid has been eradicated, the drum remnant is prepared for grafting. Small attic, marginal, or central perforations are prepared to preserve the normal drum remnant. In the case of an extensive perforation of a severely diseased membrane, the entire drum remnant is removed to the level of the annulus. The manubrium of the malleus is denuded, preserving the fibrous annulus. The mucosa of the undersurface of the drum remnant or annulus is abraded through the use of a House No. 1 sickle knife and cup forceps to ensure further an adequate recipient surface for the graft (see Fig. 12-6).

Placement of the Graft

It is imperative that excellent hemostasis be achieved before graft placement. Gelfoam saturated in 1:1000 epinephrine is packed into the middle ear space while the graft is being fashioned. A dried areolar tissue graft is removed from the Teflon block and trimmed to size (approximately 2.5 × 1.5 cm). A slit is made toward the superior aspect of the graft to accommodate placement medial to the malleus handle.

If mucosa has been removed from the middle ear, a sheet of absorbable gelatin film (Gelfilm) is trimmed and placed onto the promontory to prevent adhesions. The epinephrine-soaked Gelfoam is removed, and the middle ear is packed with saline-moistened Gelfoam starting from the eustachian tube and working posteriorly.

The graft is grasped using cup forceps, rehydrated in a physiologic saline solution, such as Tis-U-Sol irrigating solution, and placed in the middle ear. With a 22 gauge suction in the surgeon’s left hand and a right angle hook in his or her right hand, the graft is slid under the manubrium of the malleus onto the lateral attic wall. A House annulus elevator is used to tuck the fascia under the drum remnant anteriorly and inferiorly (Fig. 12-7).

With this technique, there is a point in the inferior canal at approximately the 6 o’clock position where the graft makes a transition from lying medial to the annulus to being lateral to it. The remaining graft is draped along the posterior canal wall, and the inferior canal flap with attached annulus is repositioned over the graft. Similarly, the superior flap is placed, covering the fascia lying anterior to the malleus (see Fig. 12-7). A House annulus elevator is used to even all edges of the annulus and smooth out the graft. The surgeon must ensure that flap margins are flat because buried skin may result in pearl formation. Polymyxin B and bacitracin (Polysporin) ointment is placed over the fascia graft filling the anterior sulcus. The retractors are removed, and the vascular strip is carefully replaced to its original position. The mastoid periosteum incision is closed with 3-0 polyglactin 910 (Vicryl) suture in interrupted fashion.

The postauricular incision is closed with the same 4-0 suture in a subcuticular fashion. No skin sutures are used, obviating later removal. Proper position of the vascular strip is confirmed again under direct vision through an ear speculum, and the remainder of the ear canal is filled with antibiotic ointment. A cotton ball is placed in the meatus, and a sterile, prepackaged plastic mastoid bubble dressing is applied (Fig. 12-8).

FIGURE 12-8 A sterile prepackaged mastoid dressing is applied.

POSTOPERATIVE CARE

Before discharge, the mastoid dressing is removed. A sterile, prepackaged postauricular dressing is applied behind the ear, and a fresh cotton ball is placed in the meatus of the ear canal to absorb the ointment as it liquefies. Patients are instructed to change the cotton ball at least three times per day and whenever it becomes soiled. A 3-week follow-up appointment is scheduled. Each patient is counseled about the warning signs of infection and instructed to contact the office immediately if these occur. A prescription for analgesics is given. Patients are asked to keep the ear dry and to avoid nose blowing.

By the first postoperative visit, the postauricular wound should be well healed, the ear canal should be free of ointment, and the tympanic membrane should be epithelialized. All tympanoplasty patients undergo a pure tone audiogram at this visit. By 6 weeks, the grafted eardrum has thinned considerably and assumes an appearance of a normal tympanic membrane. Follow-up visits are arranged at 6 and 12 months and yearly thereafter.

RESULTS

In 1982, Glasscock and associates ⁵ reported their experience in 1556 cases of tympanic membrane repair using the postauricular undersurface grafting technique described here. Of these cases, 663 were simple tympanoplasties, 687 involved a mastoidectomy, 54 were performed to repair a graft failure at a second stage, 38 involved a tympanoplasty with mastoid revision, and 114 were canal wall down mastoidectomies in which the tympanic membrane was grafted. Of ears, 463 (34%) had undergone at least one previous surgery. All tympanic membranes were repaired using areolar tissue, temporalis fascia, or tragal perichondrium.

Of the 1556 ears, there were 110 failures, for an overall graft success rate of 93%. Of the failures, 19 occurred within 3 weeks of surgery, 31 occurred at 3 months, 19 occurred at 6 months, and 41 occurred after 1 year. Successful grafting occurred in 91.5% of patients younger than 12 years compared with 93.3% of patients older than 12 years. The graft success rate was 92.7% in draining ears and 93.1% in dry ears. The presence of cholesteatoma had no apparent effect on success. Success rate in ears with cholesteatoma was 92% and in ears without cholesteatoma was 93.2%.

Complications were minimal in this series. Postoperative otorrhea occurred in 6%, varying from a mild otitis externa to a severe middle ear infection promoting loss of the graft. True wound infections were seen in less than 0.5%. Sensorineural hearing loss occurred in less than 1% of the cases. There were five cases of delayed facial paralysis, all of which recovered completely within 2 to 3 weeks. Serous otitis media occurred in 2%, whereas perichondritis, stenosis of the EAC, and epithelial pearls occurred in less than 0.5%.

A more recent study examined results from revision chronic ear surgery.²⁵ The authors found that control of recurrent cholesteatoma was achieved in 93% of cases. Hearing also can be significantly improved by closure of recurrent perforations or reconstruction of the ossicular chain. These authors found that hearing results after ossicular chain reconstruction were not as good for revision surgery as seen for primary surgery.²⁵ Another study by the same authors compared surgical outcomes for chronic ear surgery between smokers, former smokers, and nonsmokers.²⁶ This study showed that smokers have significantly more cholesteatomas, more canal wall down mastoidectomies, and overall worse hearing results than nonsmokers. Smokers also had significantly more postoperative complications than nonsmokers. Patients who quit smoking within 5 years of their surgery had the same risks as current smokers. In patients who quit smoking more than 5 years before surgery, the results of chronic ear surgery were no different than in patients who never smoked.

CARTILAGE GRAFT TYMPANOPLASTY

In cases of severe atelectasis of the tympanic membrane, a cartilage tympanoplasty is often indicated. Cartilage autografts have long been used in repair of canal wall defects and ossiculoplasty.²⁷^–³⁰ In 1982, Glasscock and associates⁵ first described the successful use of cartilage/perichondrial autografts for severe atelectasis, attic cholesteatoma, and posterior retraction pockets.⁵ Since that time, other authors have reported their results with this technique.^31,³²

The goal of cartilage tympanoplasty is to prevent recurrent retraction along with the long-term sequelae, including cholesteatoma formation, ossicular erosion, and progressive hearing loss. Incorporation of cartilage in the repair of the eardrum provides sufficient structural integrity to resist recurrent retraction, yet imparts minimal impedance. This technique is ideally suited for patients who have persistent eustachian tubal dysfunction, including tracheostomy patients or patients with recurrent atelectasis after standard fascia graft tympanoplasty.

Surgical Techniques

After exposure of the middle ear is obtained, the next step is to excise all diseased and atelectatic tympanic membrane. The posterior fibrous annulus is elevated from its bony sulcus with a House No. 2 lancet knife. Careful dissection is required to avoid tearing the atelectatic drum to ensure that no epithelium is left in the middle ear. To verify complete removal of an attic retraction, it is often necessary to perform mastoidectomy. Posterosuperior retractions must be elevated in continuity with the remainder of the tympanic membrane. When elevating the drum off the lenticular process and the stapes suprastructure, applying force in the posterior-to-anterior direction allows the stapedius tendon to provide countertraction, preventing inadvertent stapes subluxation. A House No. 1 sickle knife is used to elevate the diseased membrane off the manubrium and lateral process of the malleus. Fibrous adhesions are lysed, and diseased middle ear mucosa is removed with cup forceps (Fig. 12-9).

FIGURE 12-9 Standard vascular strip incisions are made. A House sickle knife opens the middle ear and elevates the atelectatic drum.

FIGURE 12-10. A, Tragal cartilage perichondrial graft is harvested by means of an incision on the posteromedial aspect of the tragus. B, The tragal perichondrium is elevated off the surface of the cartilage. C, The cartilage is trimmed to the desired size.

FIGURE 12-11. A, The cartilage perichondrial graft is positioned medial to the manubrium and fibrous annulus. The areolar tissue graft is positioned lateral to the cartilage perichondrial graft, but medial to the annulus and manubrium. B, Lateral view shows cartilage perichondrial graft in place. Ossiculoplasty is typically performed at a second stage.

To harvest the cartilage perichondrial graft, an incision is made on the posteromedial surface of the tragus (Fig. 12-10). This incision is carried through the tragal cartilage, preserving the dome of the tragal cartilage for cosmesis. A House No. 2 lancet elevator is used to elevate the perichondrium from one surface of the cartilage, leaving it hinged on the other side, similar to a book cover. The cartilage is trimmed to the proper dimensions, depending on the degree of disease present. A posterosuperior quadrant retraction often requires a cartilage graft of approximately 4 mm in diameter. For cases of atelectasis of the entire tympanic membrane, the cartilage can be incorporated into the entire pars tensa. In this situation, a wedge-shaped area of cartilage is accessed to accommodate the manubrium, if present. When using large cartilage grafts not likely to move in healing, perichondrium is not needed and is detached.

When the middle ear has been packed with moistened Gelfoam, the cartilage/perichondrial graft is placed with the perichondrium side facing laterally. The perichondrium is tucked under the manubrium and draped over the ear canal posteriorly. The cartilage should not overlap the posterior canal wall. The areolar tissue graft is trimmed to size and placed lateral to the cartilage perichondrial graft and medial to the fibrous annulus and manubrium (Fig. 12-11). This areolar graft serves to cover any remaining defects in the tympanic membrane or exposed bone in the external canal. When perichondrium is not used, the cartilage graft is placed atop the middle ear Gelfoam and medial to the tympanic membrane graft. The cartilage is ultimately enveloped by the neo–tympanic membrane. The superior-based and inferior-based canal flaps are returned to their original positions, covering the grafts as they extend onto the posterior canal wall. The external canal is filled with Polysporin ointment, and closure proceeds in the manner previously described.

Results

Results in 100 ears using cartilage tympanoplasty were reported more recently.³⁴ The retracted portion of the tympanic membrane was in the posterosuperior quadrant in 37%, the entire drum in 34%, the posterior half in 18%, the pars flaccida alone in 16%, the pars flaccida and pars tensa combined in 4%, and the anterior half in 1%. Cholesteatoma was present in 33 ears. Ossicular reconstruction was required in 52 ears; 31 of these procedures were performed simultaneously with the cartilage tympanoplasty, and 21 were staged.

Hearing results were reported in 79 ears by calculating the postoperative average air-bone gap for the speech frequencies (500 Hz, 1000 Hz, and 2000 Hz) in 10 dB increments. Of these 79 cases, 38% achieved closure of the air-bone gap to within 10 dB, 39% closed within 20 dB, and 18% closed within 30 dB. Five percent of the patients failed to show closure to less than 30 dB.

Of the 100 ears, there were 4 failures (4%) in terms of the technique itself. There were two recurrent cholesteatomas, one perforation, and one recurrent retraction. Six patients (6%) developed serous otitis media postoperatively. Of these six patients, three eventually required ventilation tubes. Fifteen patients had mild retractions that were easily controlled with modified Valsalva exercises. There were two wound infections and six cases of EAC infections. Perichondritis and EAC stenosis did not occur in this series.