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Complications of auricular correction.

The risk of complications of auricular correction is underestimated. There is around a 5% risk of early complications (haematoma, infection, fistulae caused by stitches and granulomae, allergic reactions, pressure ulcers, feelings of pain and asymmetry in side comparison) and a 20% risk of late complications (recurrences, telehone ear, excessive edge formation, auricle fitting too closely, narrowing of the auditory canal, keloids and complete collapse of the ear). Deformities are evaluated less critically by patients than by the surgeons, providing they do not concern how the ear is positioned. The causes of complications and deformities are, in the vast majority of cases, incorrect diagnosis and wrong choice of operating procedure. The choice of operating procedure must be adapted to suit the individual ear morphology. Bandaging technique and inspections and, if necessary, early revision are of great importance for the occurence and progress of early complications, in addition to operation techniques. In cases of late complications such as keloids and auricles that are too closely fitting, unfixed full-thickness skin flaps have proved to be the most successful. Large deformities can often only be corrected to a limited degree of satisfaction.

They all demonstrate specific possibilities of complication, which are considered in detail in the following chapters.

Complications of auricular correction
Complications of auricular correct can be divided into three groups: 1. complications caused by incorrect diagnosis and wrong choice of operation techniques, 2. early complications, 3. late complication (Table 1).

Complications caused by incorrect diagnosis and wrong choice of operation techniques
Auricular correction is an operation that comes under the umbrella of aesthetic surgery. As always with these types of interventions the diagnosis should originally be made by the patient themselves. A desire for correction must be deduced from this. However the treating physician must match the diagnosis to the operating technique required. An exact analysis and documentation of the type of deformity of the ear has to take place before the operation [31], [51], [66], [92]. The quality of the cartilege, the skin and the tendency to scar hyperplasia etc. should be evaluated. It was mentioned at the start that there is no universal operating procedure that is suitable for all deformities of the form and the position of the auricle. Pre-operative planning therefore requires an exact analysis of the deformity and consequently the choice of operation technique, which is also adapted to it. However, this requires the respective surgeon to manage several operation methods that correspond to the individual circumstances and requirements. Weerda emphasizes that a skilled ear surgeon is undoubtedly able to correct the various types of protruding auricle using their prefered operation technique. The surgeon must also be able to create a harmonious auricle shape using additional interventions like cavum rotation, antitragus reduction, lobu-lous reduction, narrowing of the helix and other operative additions [21], [75], [129], [130]. The pre-operative analysis of the auricle should be done both from the front view and from the side view (the same goes for the evaluation of the post-operative result). Thus for example a protruding auricle with a pronounced anthelix bulge is contraindicated for correction by Stenström. This concerns pure anthelix correction that would lead to a considerable over-emphasis of the anthelix bulge and that would also not be able to reduce the concha-mastoid angle. On the other hand a fully formed or missing anthelix fold presents a contradindicatoon of what is known as 'concha rotation' or also 'cavum rotation' because the auricle can still be protruding. However, the formation of a satisfactory antihelix structure is hardly possible. The composition of the ear cartilage can also influence the choice of operation technique [55], [75]. Very thin cartilage represents a contradiction to the anterior cut or incision technique that can lead to unsightly formation of edges. Pure stitching techniques on the other hand are not suitable for correcting thick cartilage structures. The composition of the skin can also determine the choice of operation technique. For example, in the case of a known tendency towards keloids, the diagnosis for auricular correction would be set very strictly and an operation process chosen where no extended skin incisions or excisions would be made.

Early complications 2.2.1 Haematoma
Post-operative haematoma can occur as a consequence of insufficient haemostatis. They can also be observed if the operation is done under local anaesthetic using vasoconstriction. Only after a few hours have passed since the operation does bleeding occur in the area of the operation because of reactive vessel widening. In rare cases coagulation disorders that were not recognised pre-operatively can lead to extensive subsequent bleeding ( Figure 1). Such occurrences require a rapid revision of the wound area under sterile conditions, exact haemostasis [19], [37], [101], possible drainage and light compression. Post-operative haemotomas may occur primarily following incision techniques and in principle can encourage the occurance of an infection. They are often noticed because of post-operative pain. In order to prevent a haematoma it is recommended that the auricle is modeled with pointed swabs. The use of transcutaneous mattress stitching is less common [55], [59], [92], [101]. Organised ear haemotomas that have been in existance for longer lead to indurative, scar-like thinkenings and deformities of the auricle that are difficult to correct. In collection of statistic for all operation techniques, Weerda cites haemotoma for 11 of 712 or 1.5% [124] ( Figure 2).

Infections
Wound infections can be caused by insufficient preoperative hygiene (head and hair washing). This complication requires the use of broadband antibiotics (e.g. 2 nd or 3 rd generation cephalosporin [55]) and analogous local treatment of the auricle. Stitches that are too tight should be removed. If necessary the wound edges should be spread in order to prevent overlapping of the swelling on the auricle (perichrondritis) that can lead to deformities of the auricle. This would then be a surgical emergency where prompt debridement of necrotic tissue is necessary [59], [101]. Incipient perichondritis also responds well to appropriate antibiotics and local measures. Pseudomonas aeroginosa or staphylococcus aureus are the most common causes. A swab is obligatory [120] (Figure 3). A complete overview of literature showed an infection in 3.6% of cases (22 out of 593 ears) [124].

Fistulae caused by stitches and granulomae
They can occur as an intolerance reaction to stitching materials and principally occur in corrections that are done purely through stitching techniques more frequently than with other operation techniques. Oversensitivity to the stitching material, stitches that are too close beneath the skin surface of the scar or knots or thread ends that have been cut too long are usually present. The reaction to braided polyester threads is said to be greater than to other stitch materials. Heppt et al. [55] recommend the use of undyed, non-resorbable stitches of thickess 4.0 or 5.0, retroauricular 3.0. On the other hand the use of monofilament threads is risky because the knots can easily come undone. As far as possible there should not be any stitches whose tension is too high, because this could result in stitch perforation [66]. In any case, in the presence of fistulae and granulomae, the stitching material used should be carefully completely removed. The same is also valid for ligatures or scars on the surface, whose edges can be seen through the skin of the auricle. After removal of 1-2 stitches there is usually no change in the cosmetic result. Fistulae caused by stitches are found in 9.9% of cases (53 out of 533 ears) [116], [118], [124] (Figure 4).

Allergic reactions
Allergic reactions on the skin of the auricle can occur as allergies to washing agents. However they are caused considerably more frequently by ointment bandages (iodine allegry for example). Auricle pressure bandages with antibiotic ointment are frequently used for post-operative treatment. In individual cases we could observe the most serious swellings and blister-forming dermatoses as a consequence of allergic reactions [55] ( Figure 5).

Pressure ulcers
In the case of head bandages that are too closely fitting or that dig in, pressure ulcers can occur on the skin of the auricle but also on the ear cartilage as a result of pressure necrosis. Ulcerations of this kind are usually associated with considerable feelings of pain. Removal of the bandages and inspection of the operation area and possible operative revision is indicated. The individual bandaging technique is referred to in this respect: After the operation the front and back sides of the auricle are greased with natural salve (Vaseline/Bepanthen) and the auricle contour is lined with bandaging wadding moistened with 3% carbon super oxide. Thick layers of dried wadding are placed over it and then a light compression bandage. Checks are always made on bandages after 24 hours and every 3 days if there is no pain. The bandage is removed on the 7 th to 8 th day. Because the damp bandage wadding fits directly to the auricle, it also represents an excellent prophlaxis for a haematoma and for the occurence of pressure ulcers ( Figure 6). Mattheis und Siegert [75] recommend a foam protective bandage for 7 days with betaisodona/Vaseline/salve compresses and then a forehed bandage overnight for a further 4 weeks and regular photographic documentation to check on progress. Several current studies emphasise that the post-operative bandage should be a retaining bandage and not a pressure bandage [55], [101]. Patients are made to wear a forehead bandage at night 4-6 weeks after the operation and not practise any team sports or other sports that could result in the stitches being ripped out.

Post-operative pain
Light to medium pain can occur on the day of the operation, regardless of the operation technique chosen, that makes administration of an analgesic necessary. However, the post-operative process is usually already completely painless 24 hours following intervention. Pain that persists beyond this period is always an alarm signal for one of the complications given above. Careful removal of bandages and inspection of the operation area is indicated. Frequently it is only an auricular pressure bandage that is too tightly fitted and the patients are normally pain free once the bandages have been changed [15], [23], [60], [92], [101].

Asymmetry of auricles in comparison of sides
Post-operative asymmetry, i.e. different levels of protrusion of the auricle, is usually iatrongenic if the ears have not been measured before and after the surgical intervention. Asymmetry can be avoided by measuring the distance during the operation. However, it can also occur if there are differently shaped auricles on both sides and if different operative techniques have been applied to each respective side. Insufficient stitches, torn out stitches and knot slipping etc. [75] are indicated. Asymmetry requires observation over a longer period of time because after pure stitching or incision techniques the auricle that has been operated on will only start to rebuild itself again in accordance with the natural flexural force of the cartilage after a longer time. If the asymmetry remains, a corrective operation may be undertaken after a period of 8-12 months (Figure 7) [15], [88], [97], [101].

Recurrences
Recurrences are directly dependent on the operation technique used, but they cannot be reliably ruled out with any one corrective method. It is not to be expected that the frequency of recurrence is higher with pure stitching techniques than with incision/stitching techniques. However this contradicts the number of collected statistics published by Weerda where 7.7% of recurrences (164 of 2,136 ears) were seen following the mustard technique. On the other hand the frequency of recurrences following the converse technique is 10.5% (85 of 812 ears). Recurrences are most seldom observed following incision techniques. If an auricle that has been operated on according to these methods protrudes even further, this concerns an intra-operative under-correction [46], [125], [127] (Figure 8). According to Spira [101] a slight over-correction is desirable. Reprotrusion after one year is unlikely. Reasons for recurrence could be: • too few stitches; • stitches incorrectly positioned; • excessive skin resection leads to tension in the skin that the skin itself yields to.
Mattheis und Siegert [75] observed that the same cartilage tension can principally lead to recurrences if resorbable stitches are used.

Telephone ear
'Telephone ear' is characterised by the protrusion of the upper helix edge and of the earlobe. It is a consequence of the overcorrection of the middle part of the auricle. Over-proportional resection of retroauricular skin makes telephone ear more likely to occur. It can be avoided if a dumbbell-shaped skin excision is used instead of elypsoid skin excision. The auricle should be evaluated from the front aspect in order to make any early corrections, while the patient is still on the operating table. Late corrections of telephone ear require an extended mobilization of the auricle, whereby the skin deficits have to be replaced with sealing flaps or a full-thickness skin transplant [16], [57], [115], [123] (Figure 9).

Excessive edge formations
Increased formation of edges in the anthelix area primarily occurs with pure cutting techniques and is particularly common with extremely thin auricular skin. The causes of this type of edge formation are usually incorrect incision technique, excessively deep incision of the anthelix and over-extended excision between the anthelix and the concha. Edges principally occur if the auricle is not only incidenced but also completely severed by mis-take. Sharp edges can also occur because of separation of the ventral perichondrium or incisions in the incorrect place [75]. The corrective operation can be done by careful abrasion of the cartilage in the anthelix area or by equalisation using a scalpel. According to the extent and the severity of edge formation, fascia temporalis can be used to smooth out the edges following undermining of the anterior skin, depending on the shape of the anthelix or crura. However, if the skin of the auricle is extremely thin and the formation of edges is pronounced, recreation of a soft and smooth auricle edge is hardly possible [116], [119], [121], [122] (Figure 10).

Auricle too closely fitting
An excessive correction leads to an excessively close fit of the auricle. This causes problems for aesthetic reasons, because the auricle, which does contribute to the overall impression of the face, is practically invisible from the front, giving the face a certain emptiness. The excessively close fit of the auricle is almost exclusively caused by excessive resection of the retroauricular skin ( Figure 11). If the stitches are too tight the helix may be raised, giving the impression that the ear is getting more narrow, which is described as a 'hidden helix'. The auricle that has been thus fixed on the mastoid also exhibits a variety of functional defects. Because the retroauricular fold is no longer maintained, glasses-wearers may experiences problems and directional hearing may also become more difficult. Patients with ears that have been too closely attached often complain that their hearing has become worse following the corrective operation and that they always have to search for the source of sound. Actually the hearing of patients with ears that are too close-fitting is not worse. However, their ability to locate the source of the sound is insufficient [56]. Patients with auricles that are too close-fitting also frequently complain about pain, especially when lying down. It is possible to correct these complications uising targeted lobe correction [12], [64], [87]. We have achieved considerably better results using free full-thickness skin transplants. However, care should be taken to ensure that the transplants taken are not too small, because, on the one hand, the defect to be covered is surprisingly extensive after unpicking the scar and separation of the auricle from the mastoid. On the other hand full-thickness skin transplants tend to shrink so that complications could occur again as a result. We take the grafts required from the groin region [89], [128], [131].

Narrowing of the auditory canal
This complication occurs primarily following concha rotation. Often the retroauricular skin has not been prepared widely enough from the dorsal to the mastoid and the cavum has not been stretched widely enough towards the dorsal during rotation and then fixed, when results in auditory canal stenosis. If the narrowing is more pronounced it can lead to unpleasant sensations and, in particular, to a subjective impression of hearing difficulty, which has already been mentioned in the previous chapter [48]. Narrowing of the auditory canal can prevent earphones (Walkman) from being inserted. Treatment takes the form of excision of the carilage from an incision in the auditory canal outwards.

Hypaesthesia, sensitivity to cold
Patients frequently report hypaesthesia or sensitivity to cold following auricular correction [55], [59]. In the vast majority of cases this is a temporary phenomenon that gradually returns to normal.

Keloids
A keloid is the most feared complication of wound healing. It results from scar tissue that encroaches over the original wound area onto the adjoining health tissue, like a tumour. It concerns an excessive regeneration of fibroblasts whose activity is partly influenced by growth factors from inflammation cells and from epidermal keratinocytes. The balance between synthesis and deconstruction of the dermal collogen is clearly shifted because of the disrupted interactions of these factors. A wide range of authors consider raised wound tension to be a cause of increased collagen synthesis. In addition an abnormal increase in melanocyte hormones (MSH) is assumed. This could also explain the accumulation in dark-skinned persons [67], [69], [70], [71], [72]. Some areas of the body (presternal area, outside of the upper arms, neck and shoulder areas) are predisposed to developing keloids. Keloids in the face area are extremely rare [6]. We are of the opinion that keloids following auricular correction are not exclusively determined by a corresponding predisposition, but that comprehensive skin excision also plays a role. The consequence is a continual forward pull of the ear cartilage that works against normally progressing scar formation. During the reformation of tissue as part of normal wound healing, the collagen fibres align themselves in the direction of the main pull. However, an excessively strong pull can form more connective tissue and blood vessels. The result is excessive scar formation -the keloid. For treatment of keloids a) local injections of triamcinolon and b) radiotherapy are generally indicated. However, we do not carry out either of these procedures in the ear area of children and adolescents. On the one hand triamcinolotherapy seems to us to be problematic during childhood. On the other hand radiotherapy can leave lasting damage on to the growing ear cartilage [38]. Attempts at treatment using cortisone infiltration can lead to scar tissue in keloids that are just starting or at least small. Because the solution for injection disperses very poorly, at least in the very coarse keloids, dermojet treatment should be favoured. Dermojet treatment can also be used intraoperatively if larger keloids have been removed. It is then used to prevent keloids. Radiotherapy is also used for post-operative prevention of keloids. We apply a total dose of 20 Gy (10 x 2 Gy in 3 individual sessions per week). Alternative procedures such as kryotherapy and pressure treatment are not carried out in our clinic [29].
Luckily we very seldom have to treat keloids and we do so by careful and complete excision and cover of the resulting defect with a free full-thickness skin transplant [73], [102], [103]. This is taken from the groin area. We prefer skin transplants over complete keloid excision whose frequency of recurrence is indicated at up to 60%. Weerda reported on 25 patients who did not have any further treatment after excision of a keloid. There was recurrence in all patients (100%). During 25 years we have treated a total of 17 retriauricular keloids with full-thickness skin transplants ( Figure 12, Figure 13). There was recurrence in one case where a keloid occured at the removal point -the groin region. The frequency of keloids is given in the statistics collected by Weerda with 1.8% (14 of 775) [124].

The "collapsed ear"
Collapsed ear concerns disorders that occur when all of the complications described above come together, along with the use of wholly inappropriate operation techniques, without consideration of the anatomy of the auricle [104]. We have been able to observe auricles where there were massive, coarse, induced thickenings caused by a haematoma with loss of relief of the auricle or excessive formation of edges. There are also ears where nearly the entire cartilage has clearly been removed and the remaining skin has been attached to the mastoid. (Figure 14, Figure 15, Figure 16, Figure 17, Figure 18). Such excessive deformities are usually the consequence of inadequate operation techniques that contradict all of the principles of plastic and reconstructive surgery. It is assumed that these types of disorders, whose causes are usually iatrogenous, have medical and legal consequences. It is therefore essential that exact and comprehensive pre-operative explanations are made, together with corresponding documentation.   Finally it has been determined that the correction of the protruding auricle is usually a small and relatively easy operation. However, in order to correct all forms of protruding auricles in a way that satisfies all subjective and objective criteria, several operative procedures must be managed. These must be individually adjusted to the anomaly. The choice of operation technique, the execution of the procedure and the post-operative care should be treated with the upmost care in order to avoid one or more of the complications mentioned. Their occurence is suspected to be more frequent that is normally mentioned in the literature [110].