Use of the Retroauricular Pull-Through Sandwich Flap for Repair of an Extensive Conchal Bowl Defect With Complete Cartilage Loss
Reconstruction of an extensive conchal bowl defect with notable cartilage loss is challenging due to the unique shape of the concha, the need for adequate structural support, and the lack of adjacent tissue reservoirs. Repair of a full-thickness conchal bowl defect has included 3-stage approaches, such as the anterior pedicled retroauricular flap. For an extensive conchal defect with substantial cartilage loss but intact posterior auricular skin, we recommend consideration of the retroauricular pull-through sandwich flap, which combines a cartilage graft and retroauricular interpolation flap pulled through a posterior auricular incision to resurface the anterior ear.
A preauricular banner transposition flap was used to repair the medial one-third of the conchal defect. A small area was left to heal by secondary intention (Figure 3).
Stage 2—The patient returned 3 weeks later for division and inset of the retroauricular interpolation flap. The pedicle of the flap was severed and its free edge was sutured into the lateral aspect of the defect. The posterior auricular incision that the flap had been pulled through in stage 1 of the repair was closed in a layered fashion, and the secondary defect of the postauricular scalp was left to heal by secondary intention (Figure 4).
Final Results—At follow-up 1 month later, the patient was noted to have good aesthetic and functional outcomes (Figure 5).
Practice Implications
The retroauricular pull-through sandwich flap combines a cartilage graft and a retroauricular interpolation flap pulled through an incision in the posterior auricular skin to resurface the anterior ear. This repair is most useful for a large conchal bowl defect in which there is extensive missing cartilage but intact posterior auricular skin.
The retroauricular scalp is a substantial tissue reservoir with robust vasculature; an interpolation flap from this area frequently is used to repair an extensive ear defect. The most common use of an interpolation flap is for a large helical defect; however, the flap also can be pulled through an incision in the posterior auricular skin to the front of the ear in a manner similar to revolving-door and flip-flop flaps, thus allowing for increased flap reach.
A cartilage graft provides structural support, helping to maintain auricular projection. The helical arcades provide a robust vascular supply and maintain viability of the helical rim tissue, despite the large aperture created for the pull-through flap.
We recommend this 2-stage repair for large conchal bowl defects with extensive cartilage loss and intact posterior auricular skin.