The cartilage of the external ear is much softer and more malleable in infants and young children. This knowledge can be useful to guide treatment for prominent or misshapen ears. In the newborn baby, it may be possible to mold the ear with external splints comprised of tape, glue, and silicone.1,2 Surgical correction of prominent ear is also ideally performed while the cartilage remains soft and hence surgery around the age of 5 represents a good time for this in terms of striking a balance between patient compliance, cartilage malleability, and schooling. With increasing age, it is more likely that cartilage weakening will be required as part of the surgical technique. Elderly patients my have calcification of the cartilage and this may have relevance where cartilage grafts are required for reconstruction of other areas such as the nose. The medial skin of the ear is loose fibrofatty and thick, whereas the lateral skin is more dense, adherent, and thinner. The ear grows to 85% of adult size by 3 years of age. Timing of ear development differs between the sexes. Ear development is complete 1 year earlier in girls. Maximum height and width occur at different developmental stages. In boys, maximum width typically occurs at the age of 7 years and maximum height at the age of 13 years. In girls, these occur at ages 6 and 12 years, respectively.3–6
The external ear receives its vascular supply from terminal branches of the external carotid artery. These are the posterior auricular (dominant supply) and the superficial temporal arteries. The occipital artery also contributes in a small number (7%) of patients.1,2 The other branches of the external carotid artery can be remembered with a number of different mnemonics such as Some Anatomists Love Facilitating Our Precious Medical students. The branches are therefore: • Superior thyroid • Ascending pharyngeal • Lingual • Facial • Occipital • • Maxillary • Superficial temporal
A number of nerves supply sensation to the skin of the external ear and the main one is the great auricular nerve, which is a branch of the cervical plexus C2/C3. This runs up the superficial surface of sternocleidomastoid in the neck to supply the lower two-thirds of the lateral aspect including the lobule as well as most of the medial surface with the exception of the conchal bowl and the anterior-most aspect of the upper third which includes the tragus, the helical root, and the first part of the helical rim. This nerve is at risk of injury during surgical procedures involving the neck. The auriculotemporal nerve is a branch of the trigeminal nerve (V3) that supplies sensation to the tragus, helical root, and first part of the ascending helical rim. The glossopharyngeal, vagus, and facial nerves contribute to Arnold’s nerve, which supplies sensation to the external auditory canal. The greater and lesser occipital nerves originate from the cervical plexus. The lesser occipital nerve supplies the area to the superior surface of the ear, whereas the greater occipital supplies the scalp above the ear.1,2
ears? A full assessment of the characteristics of the external ear should be made in clinic when assessing a patient for otoplasty. All abnormalities need to be identified and documented and photographed preoperatively as they will have bearing on surgical approach and likely outcome in terms of patient satisfaction. Of all the factors described, the inclination in the vertical plane is probably least important with specific reference to ear prominence, but this should still be noted and highlighted to the patient if abnormal. Although not usually addressed with surgery, some techniques will allow the lateral prominence and the inclination in the vertical plane to be altered. For example, if a postauricular pocket (mastoid region) is created then the conchal bowl can be rotated posterosuperiorly into this, thereby decreasing prominence and posterior inclination. It can then be secured with a conchomastoid suture. The depth of the conchal bowl will affect ear prominence and needs to be assessed so it may be reduced or set back if required. The strength and spring of the auricular cartilage will guide the surgical decision-making process as stiff cartilage is unlikely to respond well to suture molding alone. The angle between the helical rim and mastoid plane is relevant and should ideally be less than 30 degrees. A lobule deformity may be addressed during otoplasty surgery and must be identified preoperatively.1,2
5. Farkas LG, Posnick JC, Hreczko TM. Anthropometric growth study of the ear. Cleft Palate Craniofac J 1992;29(4): 324–329
6. Janis JE, Rohrich RJ, Gutowski KA. Otoplasty. Plast Reconstr Surg 2005;115(4):60e–72e
When placing sutures to set back the ear, it is important to ensure that the suture passes through the full thickness of the cartilage, without piercing the skin. The best way to achieve this is to feel the needle pass through the cartilage until there is slight give. Pausing for a moment with the needle in situ will allow for a check that it has not breached the skin anteriorly. Then the needle pass may be continued. When performing the deep suture placement in conchomastoid sutures, the suture should pass deep into mastoid fascia. The suture used should be permanent in most cases as this is less likely to result in recurrence of prominence. When performing otoplasty by a posterior approach, the incision should be placed close to or just in front of the posterior helical sulcus over the conchal cartilage. This is to minimize subsequent scar visibility post surgery. Many surgeons will remove a small width of skin at the same time via this incision, but this is not always necessary. When set back of the conchal bowl is planned, dissection of the ear posteriorly toward the mastoid is necessary to create a pocket in which the conchal bowl can sit. It is also necessary to gain access to the mastoid such that the scaphoconchal sutures can be placed. In order to do this, the postauricular muscles and ligaments will need to be divided or excised. This may be performed effectively with electrocautery. It is important to note that the antihelical fold is not a straight line, but actually follows a curve so scaphoconchal sutures must be placed to respect this.1–5
stresses? Gibson’s principle is based on the observation that cartilage will curl away from a cut surface because interlocking stresses are released when perichondrium is incised.1 This is analogous to scoring cardboard on one side to allow it to fold. Gibson and Davis1 published this work in 1958. Techniques that employ scoring are based on these principles. Cartilage is known to maintain its position because of the balancing forces of perichondrium on each side. When the perichondrium is incised on one side, the balance of forces is no longer equal, and the cartilage moves away from the incision. For this reason, anterior rather than posterior scoring has been more commonly performed and is generally advised for addressing antihelical fold underdevelopment. Suture techniques are termed cartilage molding procedures. For example, the Mustarde and Furnas techniques2,3 rely solely on the ability of sutures to overpower the interlocking stresses within the cartilage construct, rather than break or unbalance them. Cartilage breaking or resection techniques such as the Converse–Wood-Smith approach4 will obviously disrupt both sides of the perichondrium and the cartilage itself rather than release a single side of the perichondrium.
When performing cartilage scoring otoplasty, it is generally accepted that scoring the anterior aspect of the cartilage is preferred to release perichondrium and allow recreation of the antihelical fold. This is often now combined with a suture technique involving a posterior approach with scaphoconchal mattress sutures. It is also accepted that minimizing the anterior skin dissection is best and therefore performing anterior scoring with minimal access is the goal. In order to facilitate this an otobrader can be used via either a small cartilage fenestration or a small anterior skin incision 3–4 mm in width. Otobraders are curved instruments paired for left and right that allow progressive and controlled removal of the anterior perichondrium along the line of the planned new antihelical fold. Their use helps avoid full-thickness scoring and cartilage damage. Many of the anterior scoring techniques have traditionally involved a full-thickness cartilage incision via a posterior skin approach which may be best avoided, meaning that a closed approach would be attractive.1–4 In order to create a pocket for an anterior approach a small incision (3–4 mm) can be placed high up the ear under the helical rim, thereby leaving a well-disguised small scar. A #15 blade is ideal for this incision and tenotomy scissors can be used to dissect subcutaneously along the antihelical fold area. A 25- or 27-gauge needle is used to inject local anesthetic to the ear, while a 23- or 25-gauge needle is often used to mark the proposed antihelical fold using methylene blue. A bent 21-gauge injection needle has been used to score the cartilage anteriorly with minimal access but risks the needle tip breaking internally as the tip needs to be bent at a right angle. We have seen this occur in clinical practice.5 A Freer elevator is used to lift perichondrium from cartilage during rhinoplasty.
findings are noted: From behind, the helix to mastoid distance is 12 mm superiorly and 20 mm inferiorly. Darwin’s tubercle is a pointed thickening at the junction of the upper and middle third of the helix present in 1 in 10 individuals. This can be surgically treated with a full-thickness excision of the skin and the underlying prominent cartilage (Fig. 33.2). Because it is such a common finding with variation in severity, it may actually need no treatment at all. Aside from the description of Darwin’s tubercle, the other measurements are all in keeping with a normal ear (Box 33.1 and Fig. 33.3).1,2 Stahl’s ear refers to the presence of a third and/or horizontal superior crus with a pointed upper helix. Sometimes this is termed “Spock ears” and is associated with upper and mid-third helical prominence. A mastoid prominence will alter the appearance of the postauricular valley and can be surgically managed with either soft tissue or bone resection of this area. BOX 33.1 BASIC GOALS OF OTOPLASTY • Correction of all upper third protrusion • Visibility of the helix beyond the antihelix when viewed from the front • Smooth and regular helix • No marked distortion or decrease in the depth of the postauricular sulcus • Correct placement of the ear The helix-to-mastoid distance falls in the normal range of 10–12 mm at the top, 16–18 mm in the middle, and 20–22 mm in the lower third. • Bilateral symmetry The position of the lateral ear border to the head matches within 3 mm at any point between the ears. • Smooth, rounded, and well-defined antihelical fold • Conchoscaphal angle of 90 degrees • Conchal reduction or reduction of the conchomastoidal angle • Helical rim that projects laterally farther than the lobule Fig. 33.2 Darwin’s tubercle. Darwin’s tubercle Incision on edge of Darwin’s tubercle Skin incision flush with edge of helical rim Skin incision flush with edge of helical rim Cartilage incision flush with edge of helical rim Fig. 33.3 Correct placement of ear. 5.5-6.5 cm 5.5-6.5 cm 55-60% of ear height 20° 21-30° Scalp Helix Antihelix 2-5 mm projection Fig. 33.4 Stahl’s ear. A B C D
Stahl’s ear involves the presence of a third and/or horizontal superior crus with a pointed upper helix. This results in a pointy prominence in the upper and middle third of the ear (“Spock ear”). This has been traditionally felt to be challenging to correct. However, the most predictable and effective approach to treat Stahl’s ear deformity is complete excision of the third crus through the helical rim.1 The excised superior crus can then also be used as an onlay graft to create a superior crus if it is absent. The incision for this is within the scapha, similar to scapha reduction and a small scaphal cartilage excision may be used to facilitate forward rotation of the helical rim. The third crus is excised completely with a wedge excision of the helical rim skin extending onto the back of the ear. When closed, the wedge excision aids in forward rotation of the helical rim (Fig. 33.4).
Following otoplasty, most surgeons will advise patients to wear a headband at night for 3 months to protect the ears from mechanical trauma leading to recurrence of prominence. Although this is not evidence based, it makes sense in terms of wound healing and tissue remodeling. Following surgery, it is standard practice to protect the ears with layered dressings and a head bandage or similar. This is removed sometime between 4 and 7 days. Hematomas probably represent the most common early complication and present with increasing pain in the first 24 hours after surgery. They should be treated swiftly with evacuation and hemostasis to reduce the risk of skin necrosis. Infection is a rare complication and is most likely due to Staphylococcus. It can in some circumstances lead to chondritis, which may need surgical debridement. Reoperation may be required following otoplasty, but this may not be solely due to recurrence of prominence. For example, it may be associated with suture problems such as sinuses, foreign body reaction, or extrusion. It may be for scar revision or adjustment for asymmetry.1,2