The external ear is supplied by three main arterial vessels: the posterior auricular (dominant supply), superficial temporal, and occipital. All three of these are branches of the external carotid artery. The other branches are the lingual, facial, superior thyroid, maxillary, and ascending pharyngeal. The deep temporal artery is a branch of the maxillary artery. The great auricular artery does not exist (although there is a great auricular nerve). Good interconnections exist between the main source vessels. The ear can be replanted on either the superficial temporal or posterior auricular vessels (Fig. 43.1).1–3 Fig. 43.1 Vascular supply to the external ear. Superficial temporal artery Perforating artery Posterior auricular artery
2. Park C, Lineaweaver WC, Rumly TO, Buncke HJ. Arterial supply of the anterior ear. Plast Reconstr Surg 1992;90(1):38–44
The lymphatic drainage of the ear corresponds to the embryologic origins. The tragus, helical root, and superior helix all originate from the first branchial arch and drain to the parotid nodes. The antihelix, antitragus, and lobule all arise from the second branchial arch and drain to the cervical nodes. When examining patients with squamous cell carcinoma or melanoma of the ear, it is vital that the parotid and neck nodes are thoroughly assessed, given the pathway of spread in metastatic disease. Often patients with metastatic disease originating from the ear will require both parotidectomy and neck dissection.1–4
4. Pan WR, le Roux CM, Levy SM, Briggs CA. Lymphatic drainage of the external ear. Head Neck 2011;33(1):60–64 The ear is located one ear height (not one width) posterior to the lateral orbital rim. The superior surface is usually at level with the eyebrow. Height varies between 5.5 and 6.5 cm in adults, and width is usually a little over half the height. Projection varies among individuals but is usually greatest inferiorly (approximately 2 cm) from the mastoid to the helix. The long axis tilts on average 20 degrees posteriorly, but this varies greatly.1
prevent cauliflower ear. Cauliflower ear refers to a deformity that develops after a subperichondrial hematoma in the pinna. It results in devascularization of the cartilage with permanent fibrosis and scarring. Preventative management involves early evacuation of the hematoma and application of a pressure dressing.1 Dog bites are commonly seen in children, but the pathogens involved in infection are most likely Pasteurella multocida or P. canis. Viridans-group streptococci are associated with human bites.2,3 Ear lacerations should be carefully debrided and repaired with skin-only closure. Frostbite should be managed with rapid rewarming using saline-soaked dressings. To preserve maximal tissue, thermal burns are usually treated conservatively with dressings and later debrided once demarcation has occurred.
Keloids represent fibroproliferative disorders of the skin that grow beyond the boundaries of the original wound. They can occur spontaneously but commonly occur secondary to localized trauma. The most common anatomic site for development of a keloid is the lobule and this is frequently secondary to ear piercing. Other trauma or surgery to the ear such as otoplasty risks development of keloid scarring and this must be communicated to patients before proceeding with such techniques. Sites other than the head and neck that are affected include the anterior chest, lateral arm, and some flexor surfaces.1,2
Ear piercing is the most common cause of keloids on the ear and may be associated with postpiercing infection or foreign body reaction. Keloids are 15 times (not 5 times) more frequent in dark-skinned individuals than in white individuals.1 Keloids recur after simple excision in up to 100% of cases. Outcomes after combined excision and steroid therapy are still unpredictable and vary from 0 to 100% recurrence.2 Continuous silicone therapy for 3 months after surgery can significantly decrease potential keloid formation. Radiation should be reserved for resistant lesions because of the side effects. Alternatively, it may be combined with surgical excision to provide a more reliable outcome.1–3
Chondrodermatitis nodularis helicis (CDNH) is a benign condition affecting the external ear resulting in a painful, chronic nodular, or ulcerative lesion. Patients notice these lesions because of the pain. This is in contrast to some asymptomatic ear lesions such as nodular basal cell carcinoma (BCC), where a patient’s relatives often first notice the lesion. Males are four times more likely to develop CDNH, which is thought to be as a result of repeated external pressure being placed on the ear. When taking history, patients’ sleeping position preference should be noted, as often they sleep lying on the affected side and this needs to be modified as part of the treatment plan. Lesions are treated surgically with a narrow margin excision. The key point is to remove the lesion while ensuring a smooth contour to the ear cartilage, such that no residual prominence remains. Recurrence rates vary between 10 and 30% according to series1 and this can be affected by both surgical technique and subsequent pressure relief.1,2
Successful replantation of the ear following an injury like this can provide a superior aesthetic result compared with secondary reconstruction. It requires arterial anastomosis with either the superficial temporal or posterior auricular artery. An additional venous anastomosis is preferable but not always technically possible, so venous drainage may be reliant on an external route into dressings or supplemented with other modalities.1,2 Prosthetic ears manufactured with a silicone elastomer can provide a very good aesthetic result for many patients and they are often, but not exclusively, bone-anchored devices. However, in this young patient with a clean-cut amputation, proceeding directly to prosthesis would not be indicated.3,4 Cartilage banking can be a useful approach in cases where vascularized replantation is not feasible. The benefit of this approach is that the cartilage framework can be preserved and later inset under a vascularized skin or fascial flap such as the temporoparietal fascial flap.5 The temporoparietal fascia should always be preserved for secondary ear reconstruction and not used for acute wound coverage. Autologous reconstruction of the ear may be considered in this patient if the replantation process failed. Ear reconstruction would not be performed in the acute setting though and is an elective, staged procedure. Reattachment of small composite grafts can be successful, but in a large area such as this case, the graft would fail.
During replantation of the ear, it may not be possible to achieve a satisfactory venous anastomosis. For this reason, leeches (Hirudo medicinalis) are commonly used as standard practice. They are typically used both in the presence or absence of a venous anastomosis. Sulfamylon (mafenide acetate) is used on ear burns as part of a conservative measure to minimize tissue loss and infection. Cartilage banking is performed in cases where replantation cannot be performed. Cartilage may be buried under a postauricular skin pocket or the forearm. The success of this approach is variable. Dextran and heparin are part of the treatment for frostbite to the ear. They are intended to limit thrombosis and tissue loss. Either may be used in ear replantation but are not a core part of treatment. Aspirin may help the arterial anastomosis but it is not evidence based.1,2
Use of a full-thickness skin graft works well on the ear, particularly on the conchal bowl or scapha when the anterior or posterior skin remains intact and can accept a graft reliably. Providing the remainder of the ear construct is intact, there is no structural loss associated with conchal bowl defects (hence the suitability of this area for cartilage graft harvesting). Often the defect is difficult to see once the graft has healed well and matured for some months postoperatively. In contrast, if this defect was allowed to heal by secondary intent, there would be significant distortion and the aesthetic result would be poor. A split-thickness graft could be taken and provide a fair result; however, the contour and color would be worse than with the full-thickness graft and the donor site would need to be left to reepithelialize and such wounds can often be painful and more involved to manage than full-thickness donor sites. A preauricular transposition flap would work for this defect but would not add much to the aesthetics compared with a graft and actually would risk creating fullness at the flap base where the flap was transposed and inset. There is no rationale for using cartilage graft to reconstruct this defect as the structural and aesthetic outcomes are not affected by the absence of cartilage at this site. If a cartilage graft was to be used, a vascularized skin flap would also be required to cover it.1,2
The Antia-Buch flap1 is a very useful technique for reconstruction of helical rim defects up to approximately 2 cm in height (Fig. 43.2). An anterior incision is made in the helical sulcus through skin and cartilage and a posterior skin flap dissection is performed. This undermining allows advancement of the helix and lobule vertically toward the defect. The helical root is also released and advanced as a V-Y flap, although this part is not always required for smaller defects especially in elderly men with tall ears and long lobules. A variation of this is the swing flap which is based on the superior part of the Antia-Buch flap that can be used for larger defects of the helical rim. It involves raising a helical root and superior rim flap on a mesentery without the posterior skin (which is elevated thinly). If the defect was greater than 2 cm tall then Converse’s tunnel technique may be useful. This involves burying a piece of contralateral auricular cartilage under the postauricular skin and dividing and insetting the flap after 3 weeks.2 The chondrocutaneous composite flap is indicated for reconstructing superior third, full-thickness ear defects rather than the helical rim alone. It involves raising an anteriorly based flap on the root of the ear passing into the conchal bowl. This is transposed to the top of the ear and the donor site grafted as posterior skin is left in situ. Dieffenbach’s flap is used for combined middle third defects of the scapha and helical rim. It involves raising a postauricular skin flap placed over a contralateral auricular cartilage graft. This flap is also divided at 3 weeks.2 The valise handle technique is a staged reconstruction used for superior third defects of the ear rather than the helical rim alone. In the first stage, contralateral ear cartilage is implanted subcutaneously close to the defect. After 3 weeks the inferior helix is transposed to the cartilage graft. After a further 3 weeks, a bipedicled composite flap is elevated as a valise handle and skin graft is applied to the posterior sulcus to increase ear projection. A B C Fig. 43.2 The Antia-Buch procedure of helical rim advancement.
Wedge excision of the split earlobe is a standard and effective technique for repairing a vertically split or cleft earlobe. In cases where the patient wishes to preserve the earring tract, techniques such as Pardue's flap can be used to maintain a skin-lined channel for earrings. Lobule reduction is indicated in patients with large lobules who wish to reduce the size of the lobules and the overall visual appearance of the ear. They are also indicated in patients who have used tissue expanding earrings for an extended time and want to return to a more anatomical appearance for their lobes. Composite grafts from the contralateral lobe and posteriorly based skin flaps are indicated for lobe reconstruction rather than split earlobe repair. Neither local flaps of grafts would normally be needed for surgery to the lobe.
Dieffenbach’s flap is a two-stage reconstruction process of the ear that is well suited to reconstruct full-thickness defects of the middle section where the defect spans the helical rim and scapha as in this case. In the first stage, a contralateral ear graft is sutured into the defect and the postauricular skin is elevated and advanced over the cartilage graft to fill the defect. The postauricular skin is then divided at 3 weeks.1 The Converse tunnel technique could potentially be useful here but tends to be used more for isolated helical rim reconstruction.1 Orticochea has been associated with many different flaps in the head and neck including the scalp and speech surgery, but in this case the flap is a composite chondrocutaneous rotation flap for upper and middle third ear defects. It is based on the lateral helical rim.2 The flip-flop flap is used to reconstruct conchal defects and involves a postauricular island flap that is elevated consisting the skin, postauricular muscle, and fascia. The flap is rotated anteriorly 180 degrees so that the posterior most aspect of the flap becomes anterior along the antihelix. The anterior most aspect of the donor flap is deep in the conchal bowl.3 Staged tubed pedicle flaps using the postauricular skin work well for reconstruction of the helical rim. They require three stages: in the first stage the skin is tubed; in the second stage one end is divided and inset into the helical rim; and in the third stage the flap is detached posteriorly and inset into the helical rim. If the rim is subsequently droopy, it may be necessary to insert a small cartilage graft within the reconstructed soft tissue in order to provide additional support.