Cartilage Tympanoplasty - Clinical Tree

Please access Videos to view the corresponding videos for this chapter.

The use of cartilage in middle ear surgery is not a new concept. From the original description by Salen of using septal cartilage for myringoplasty, interest and techniques have developed. Unfortunately, the initial published audiological outcomes did not differentiate type I cartilage tympanoplasty from cartilage ossiculoplasty, and the poor results of the latter were associated with the former. Hence, enthusiasm for the technique diminished, although it continued to be used on a limited basis to manage retraction pockets. More recently, the use of cartilage has been increasingly described for the reconstruction of large portions of the pars tensa of the tympanic membrane in cases of recurrent perforation, atelectasis, and cholesteatoma. Although one may anticipate a significant conductive hearing loss with cartilage because of its thickness and rigidity, several studies have reported results to the contrary, suggesting the hearing results with cartilage to be no different from those with fascia. Experimental and clinical studies have reported that cartilage is well tolerated by the middle ear and that long-term survival is the norm. Cartilage grafts appear to be nourished largely by diffusion and become well incorporated in the tympanic membrane. Human and animal studies have demonstrated that although some softening occurs with time, the matrix of the cartilage remains intact but develops empty lacunae, revealing chondrocyte degeneration. ^, The cartilage graft retains its rigid quality and resists resorption and retraction, even with continuous eustachian tube dysfunction.

Two distinct techniques are commonly employed for cartilage reconstruction of the tympanic membrane: the perichondrium and cartilage island flap, which uses tragal cartilage, and the mosaic technique (formerly referred to as the palisade technique), which uses cartilage from the tragus or cymba. The choice of technique is typically dictated by the specific middle ear pathology or, in cases where the tympanic membrane reconstruction is in conjunction with ossiculoplasty, the status of the ossicular chain. The mosaic technique is preferred in cases of cholesteatoma and when ossicular reconstruction is needed with the malleus present. In this case, an exact fit is necessary to prevent cholesteatoma recurrence. The perichondrium and cartilage island flap is preferred for the management of atelectatic ears and high-risk perforations. This chapter describes the two techniques in detail, followed by descriptions of the modifications in response to specific surgical indications.

Patient Selection

Generally, cartilage is used as a graft material in any ear at high risk for failure with the traditional techniques using temporalis fascia or perichondrium. Included in this group are patients with high-risk perforations, atelectatic ears, and cholesteatoma and pediatric patients. High-risk perforation comprises a revision surgery, a perforation anterior to the malleus, a perforation draining at the time of surgery, a perforation larger than 50%, or a bilateral perforation, each of which has been shown to be associated with increased failure rates using traditional techniques. ^, The atelectatic ear is one of the most important indications for cartilage tympanoplasty, and numerous reports have established its efficacy over fascia in this situation. For similar reasons, the use of cartilage to reconstruct and reinforce the scutum and posterior half of the eardrum in cholesteatoma surgery has reduced the incidence of recurrent atrophy and retraction pockets in these difficult cases.

Cartilage tympanoplasty has proven efficacious in pediatric and adult patients, with special precautions used in the former group. The general approach to pediatric patients is to avoid repairing the tympanic membrane during the otitis-prone years (<3 years of age). If the contralateral ear is normal, routine tympanoplasty is performed at age 4 years. If the contralateral ear is abnormal at this time, adenoidectomy is considered, and tympanoplasty is generally deferred until age 7 years. ^, If contralateral disease is still present, the ear may be considered at high risk for failure. Cartilage tympanoplasty is then performed on the poorer-hearing ear. This is considered the “sentinel ear” as it predicts the outcome in the better-hearing ear.

As part of the preoperative preparation, all patients are encouraged to perform the Valsalva maneuver (or use the Otovent [Invotect International] in younger children). Patients unable to insufflate the ear are placed on nasal steroids 6 weeks before surgery; these are continued in the postoperative period until an aerated middle ear cleft is documented. Although we have identified no difference in graft take between patients who can and cannot perform the Valsalva maneuver, we have found a slightly increased need (7%) for postoperative tube insertion in the Valsalva-negative group. Likewise, an attempt is made to optimize concomitant sinonasal disease (allergy, chronic sinusitis) before ear surgery, and smoking cessation is encouraged where applicable. The draining ear is treated with antibiotic and steroid-containing topical solutions and aural toilet for 6 to 8 weeks before surgery. Although every attempt is made to dry an ear before surgical intervention, it is not considered a prerequisite for tympanoplasty.

Surgical Technique

General Considerations

An excellent resource for a complete description of the various cartilage tympanoplasty techniques is provided by Tos. In this chapter, we will discuss the two underlay techniques we commonly employ.

The surgical approach for cartilage tympanoplasty does not differ from that for traditional otologic surgery and is dictated by the extent and location of the disease. The postauricular approach is used in most patients because these cases, by definition, usually have more extensive middle ear pathology. A small, localized, posterior retraction or perforation can be performed through a transcanal or endaural incision, but great care must be taken to ensure that the depths of the retraction can be reached. Likewise, the placement of the cartilage graft uses the underlay technique, so no special tympanomeatal flaps or skin incisions are required.

Some general observations should be made regarding the differences in cartilage that occur with aging. The cartilage thickness of the tragus and cymba is not appreciably different between children and adults, but the perichondrium appears more adherent in children. For this reason, when the perichondrium is removed from one side when fashioning the graft (described later), care must be taken to ensure the correct plane is dissected, especially in children. Likewise, cartilage is more pliable in children, making it slightly easier to work with than adult cartilage, which can become brittle in patients older than 65 years. For this reason, during the fashioning of the graft, it is generally a good practice to manipulate and hold the cartilage with the fingers instead of forceps, and toothed forceps should never be used to grasp the cartilage to avoid fracture.

The perichondrium is generally left attached to the side of the cartilage that faces the ear canal, regardless of technique. The perichondrium is considered to improve graft stability and facilitate the ingrowth of fibrous tissue and epithelialization. With the mosaic technique, however, perichondrium has occasionally been removed from both sides of the cartilage because of untoward curling of the graft, which typically curves toward the side with the perichondrium. No adverse effect has been noted, other than the increased fragility of the graft during formation and placement.

You're Reading a Preview

Become a Clinical Tree membership for Full access and enjoy Unlimited articles

Become membership

If you are a member. Log in here