If you don't remember your password, you can reset it by entering your email address and clicking the Reset Password button. You will then receive an email that contains a secure link for resetting your password
If the address matches a valid account an email will be sent to __email__ with instructions for resetting your password
Address reprint requests and correspondence: Jacqueline J. Greene, MD, Massachusetts Eye & Ear, Harvard Medical School, 243 Charles St, 9th floor Facial Nerve Center, Boston MA, 02114.
The Karapandzic flap is a reliable reconstructive option for medium and large lip defects that maintains sensation and motor function and optimizes tissue vascularity.
The reconstructive challenges in medium and large lip defect repair comprise balancing functional restoration (oral competence, speech and facial expression) with aesthetic outcomes. Medium (one-third to one-half of the lip) or large (greater than two-thirds of the lip) lip defects disrupt the continuity of the oral sphincter muscle, the orbicularis oris, as well as involve multiple aesthetic subunits of the lip. Local rotational flaps can compromise sensory nerve branches of the infraorbital nerve to the upper lip and the mental nerve to the lower lip, leading to an insensate lip that can cause oral incompetence and resulting in chronic dental trauma and speech difficulties. Transection of distal facial nerve branches to the orbicularis oris, buccinator, and lip elevator and depressor muscles can lead to an adynamic lip and likewise cause functional deficits.
is an effective reconstructive choice for both medium and large upper and lower lip defects. Originally, the Karapandzic flap was a modification of the Gillies fan flap, which was useful for large lip defect repair as a full-thickness pedicled rotational flap, but often resulted in oral incompetence due to interruption of neurovascular structures.
The Karapandzic flap differs from the Gillies fan flap in that a full-thickness incision is avoided and critical neurovascular input to lip musculature is kept intact through careful dissection in the subcutaneous and muscular planes, thus preserving natural sensation, and optimizing tissue vascularity and muscle function.
The Karapandzic flap is an axial musculomucocutaneous flap based on the superior or inferior labial arteries (Figure 1A and B). It is designed around the melolabial and labiomandibular creases (Figure 1C), which divide the facial subunit borders between the upper and lower lips and the cheek. Adequate lip and cheek tissue is necessary for full mobilization of the flap and previous surgical excisions or scarring may limit flap rotation. Karapandzic flaps are ideal for large lower lip defects and central upper lip defects, but may cause philtrum deviation for lateral upper lip defects.
Functionally, the Karapandzic flap preserves lip mobility, oral competence, articulation, and emotional expression. The most common complication of the Karapandzic flap is microstomia, more commonly seen when used as reconstruction for larger defects,
and should be taken into account for patients who wear dentures, have difficult airway access or require multiple dental procedures.
Figure 1(A) Cross-section of upper lip demonstrating superior labial artery in a submucosal plane deep to the orbicularis oris muscle at the level of the vermillion border, (B) cross-section of lower lip demonstrating location of inferior labial artery in submucosal plane deep to orbicularis oris muscle, and (C) locations of the melolabial, labiomandibular and mental creases.
It is best to carefully mark the patient's melolabial, labiomandibular and mental creases (Figure 1C) while the patient is awake and sitting upright in the preoperative area. While older patients may possess melolabial creases at rest that are easily marked, younger patients with functioning facial nerve should be asked to smile to exhibit the melolabial crease. The melolabial crease can also be seen and marked by palpating the philtrum and lateralizing it to render the facial crease more visible. Nasotracheal intubation is required to prevent perioral distortion during the procedure. Antibiotics covering oral flora such as Unasyn (Ampicillin/Sulbactam) or Zosyn (Piperacillin/Tazobactam) are given preoperatively. The entire face is prepped with Betadine (Povidone-iodine) or alcohol extending down to the clavicle. Small injections with a vasoconstricting agent such as epinephrine (1:100,000) into the subcutaneous tissues will aid with visualization during the procedure. Lidocaine should be avoided in order to prevent neural blockade. Long-lasting neuromuscular blockade should be avoided due to the need to identify and stimulate distal facial nerve branches.
Incision lines should be drawn along the melolabial creases bilaterally or unilaterally depending on the size of the lesion. For upper lip defects requiring bilateral flap reconstruction, the incision extends from the nasal base, along the melolabial crease to the labiomandibular crease (Figure 2). For lower lip reconstruction with bilateral Karapandzic flaps, the mental crease connects the incision from the labiomandibular creases (Figure 1C and 3).
Figure 2Upper lip reconstruction with the Karapandzic flap.
The flap incision should extend to the superior aspect of the melolabial fold at the alar base for sufficient flap rotation. The incision is made through the skin followed by careful blunt dissection in the subcutaneous tissue to identify branches of the facial artery including the angular artery, superior labial artery, and inferior labial artery. The superior labial artery is found between the oral mucosa and orbicular oris muscle, above the junction of the vermilion and mucosa and anastomosing with the opposing artery on the contralateral side(Figure 1A).
The inferior labial artery is found in the submucosal plane, generally traveling medially and deep to the orbicularis muscle, at the level of the vermilion line (Figure 1B).
The branches of the infraorbital nerve (Cranial Nerve V2) and the mental nerve (Cranial Nerve V3) are carefully dissected, and gently retracted with vessel loops during flap elevation to preserve sensory innervation. Distal branches of the facial nerve may be difficult to locate but can be identified with nerve stimulation and are generally found deep to the lip elevator and depressor muscles, but superficial to the mentalis muscle. Separation of the subcutaneous tissue from other facial musculature should be performed gently and bluntly with scissors to prevent disruption of the key vascular and neural structures. Hemostasis is achieved using limited bipolar cautery to avoid nerve injury.
The orbicularis oris muscle is dissected carefully to detach it from adjacent soft tissue and obtain the required flap mobility, but minimizing release from the lip elevator and depressor muscles at the modiolus, which could affect lip movement. Muscle release needs to be greatest at the level of the flap closest to the defect that was resected. Attempts should be made to preserve the lip elevator and depressor muscles including the levator labii superioris, levator anguli oris, zygomaticus major and minor, depressor labii inferioris, and depressor anguli oris, but muscle release may be required to achieve sufficient medial mobilization of the flaps and closure of the lip defect. The mucous membrane is not generally divided except for a small length at the defect boundary to allow for closure; for large defects, a releasing mucosal incision may be needed for full flap mobilization.
The degree of medial rotation of the myocutaneous flaps depends on the defect site. If the defect was central in origin, both flaps should be rotated equally. If the defect occupies the lateral upper or lower lip, the contralateral flap rotation should be greater to minimize upper lip distortion. Lateral upper lip defects that are reconstructed with bilateral Karapandzic flaps can distort the philtrum and should be planned carefully. Alignment of the vermillion border is essential for aesthetic results and should be carefully reapproximated early in closure with an initial suture to prevent stepoff. The continuity of the orbicularis oris muscle should be reestablished during closure to restore the oral sphincter. Closure of the mucosa and the wet-dry transition of the lip should be performed with resorbable interrupted sutures. Depending on the tension of the closure, several deep and superficial sutures should be placed during this multilayer closure. Finally, the skin incision can be closed with nonabsorbable sutures in multiple segments.
Postoperatively, the patient is started on a clear liquid diet that is then advanced as tolerated. The patient should be prophylactically treated perioperatively for nausea and vomiting so as to minimize the risk of splitting the flap closure. Postoperative antibiotics beyond perioperative dosing are generally not indicated.
Complications
The most cited complication of the Karapandzic flap is microstomia. This occurs to a variable degree across patients, although tends to be more evident in those who rely on dentures or whose defect was large and required significant medial flap rotation.
If the microstomia is severe enough to prevent appropriate oral intake or dental hygiene, a subsequent commissuroplasty may be needed to improve oral dilation. Additional complications include visible scarring, altered sensation, upper and lower lip mismatch, and commissure blunting.
In one study of 65 patients who underwent Karapandzic flap reconstructions for resections ranging from 1 to 3.6 cm in size (mean 2.0 cm, 98% with negative margins), the most common complications were altered sensation (n = 13) and lip tightness (n = 7).
There were no patient complaints with using cutlery or a normal postoperative diet. Generally, hematomas, flap necrosis, and wound infection are rare complications.
Patient selection is critical to ensure successful functional and aesthetic lip reconstruction. The Karapandzic flap may not be the optimal reconstructive option for patients with significant dental comorbidities or difficult airway access given the risk for microstomia. All patients with comorbidities including trismus or mandibular hypomobility should be cautioned about worsening symptoms. Lip lesions involving the commissure tend to have greater contracture
In this technique, the width of the transferred flap should still equal the vertical height of the lip defect, as it will be rotated into the vertical position. Burrow's triangles are excised from the lower cheek to aid in closure. Neurovascular structures are similarly carefully dissected and preserved. Given an increased flap length needed, incisions do not have to be along the melolabial creases. The buccal mucosa is everted and ultimately replaces the vermilion lip in the location of the cheek extension.
Because of this, the flap requires more buccal mucosa than skin for sufficient oral reconstruction. Ultimately, this extended technique allows for reconstruction of larger defects while limiting the extent of microstomia.
In summary, the Karapandzic flap is a reliable reconstructive technique for functional and aesthetic outcomes following both upper and lower lip defects.
Funding
None.
Conflicts of interest
The authors have no conflicts of interest relevant to this article to disclose.
Financial disclosure
The authors have no financial relationships relevant to this article to disclose.
References
Karapandzic M.
Reconstruction of lip defects by local arterial flaps.
30089-2&id=gr1.jpg){kind=link}
30089-2&id=gr2.jpg){kind=link}
30089-2&id=gr3.jpg){kind=link}