Perichondrium Cartilage Island Flap

The general technique of reconstruction using the perichondrium/cartilage island flap begins with harvest of the cartilage from the tragal area.28 An initial cut through skin and cartilage is made on the medial side of the tragus, leaving a 2-mm strip of cartilage in the dome of the tragus for cosmesis (Fig. 6-1). The cartilage, with attached perichondrium, is dissected medially from the overlying skin and soft tissue by spreading a pair of sharp scissors in a plane that is easily developed superficial to the perichon-drium on both sides. At this point, it is necessary to make an inferior cut as low as possible to maximize the length of harvested cartilage. The cartilage is then grasped and retracted inferiorly, which delivers the superior portion from the incisura area. The superior portion is then dissected out while retracting, which produces a piece of cartilage typically measuring 15 x 10 mm in children and somewhat larger in adults.

The perichondrium from the side of the cartilage furthest from the ear canal is dissected off, leaving the thinner perichondrium on the reverse side. A perichondrium/cartilage island flap is constructed as described previously.28 Using a round knife, cartilage is removed to produce an eccentrically located disk of cartilage about 7 to 9 mm in diameter for total TM reconstruction. A flap of perichondrium is produced posteriorly that will eventually drape over the posterior canal wall. A complete strip of cartilage 2 mm in width is then removed vertically from the center of the cartilage to accommodate the

FIGURE 6 — 1 Harvest of cartilage, leaving small rim of cartilage in dome for cosmesis (right ear).

1 SOM

FIGURE6—2 Prepared perichondrium/cartilage island graft, showing strip of cartilage removed to facilitate malleus.

entire malleus handle (Fig. 6—2). The creation of two cartilage islands in this manner is essential to enable the reconstructed TM to bend and conform to the normal conical shape of the TM. When the ossicular chain is intact, an additional triangular piece of cartilage is removed from the posterior-superior quadrant to accommodate the incus. This excision prevents the lateral displacement of the posterior portion of the cartilage graft that sometimes occurs because of insufficient space between the malleus and incus.

The entire graft is placed in an underlay fashion, with the malleus fitting in the groove and actually pressing down into and conforming to the perichon-drium, as shown in Figure 6—3. The cartilage is placed toward the promontory, with the perichon-drium immediately adjacent to the TM remnant, both of which are medial to the malleus. Failure to remove enough cartilage from the center strip will cause the graft to fold up at the center instead of lying flat in the desired position. Likewise, if the strip is insufficient, the cartilage may be displaced

Perichondrium

Cartilage Malleus

Perichondrium

Cartilage Malleus

FIGURE 6-4 Postoperative ear with perichondrium/ cartilage island graft (left ear).

FIGURE 6—3 Lateral line drawing demonstrating proper placement of graft.

FIGURE 6-4 Postoperative ear with perichondrium/ cartilage island graft (left ear).

medially instead of assuming a more lateral position in the same plane as the malleus.

Gelfoam (Upjohn Laboratories, Kalamazoo, MI) is packed in the middle ear space underneath the anterior annulus to support the graft in this area, and the posterior flap of perichondrium is draped over the posterior canal wall. Middle ear packing is avoided on the promontory and in the vicinity of the ossicular chain. One piece of Gelfoam is placed lateral to the reconstructed TM, and antibiotic ointment is placed in the ear canal (Fig. 6-4).

Was this article helpful?

0 0
Hearing Aids Inside Out

Hearing Aids Inside Out

Have you recently experienced hearing loss? Most probably you need hearing aids, but don't know much about them. To learn everything you need to know about hearing aids, read the eBook, Hearing Aids Inside Out. The book comprises 113 pages of excellent content utterly free of technical jargon, written in simple language, and in a flowing style that can easily be read and understood by all.

Get My Free Ebook


Post a comment