Reconstructing Large Facial Defects by Optimizing the Utilization of Expanded Flap

Abstract

Objective:

This study aimed to investigate the optimization of expanded flaps for the repair of large facial defects, while also providing insights and strategies for the prevention and management of complications.

Methods:

A retrospective study was conducted with 5 patients who underwent repair of skin soft tissue defects of the head and face with expanded flap at First Affiliated Hospital of Kunming Medical University between October 2018 and May 2021. Patient data were collected, including age, diagnosis, lesion area, and photographs, together with details of the type, volume, placement, and depth of the expander, the duration of expansion, the type of flap used for repair, and follow-up results. All patients with large soft tissue defects of the head and face, resulting from the resection of benign lesions, underwent preoperative implantation of expanders. The defects were subsequently repaired by established flap design principles after the expanded flap was obtained through continuous water injection and expansion.

Results:

All 5 patients underwent successful surgery with complete flap survival. In 1 case, a failure of forehead expander placement was addressed by utilizing a expanded flap derived from the remaining 2 expanders. In addition, a case of cheek expander infection was resolved through the removal of the infected expander and repair using a expanded flap from the neck expander. One patient did not return for treatment of postoperative incisional scar hyperplasia due to her predisposition to keloids. The remaining 4 patients were actively followed postoperatively and exhibited flaps that closely matched the surrounding skin in color and texture. All patients were satisfied with their postoperative results and appearance.

Conclusions:

In cases of significant soft tissue defects following the resection of benign cephalofacial lesions, the utilization of expanding flap repair is a practical and effective approach. When employed optimally, this technique results in more satisfactory postoperative outcomes and a reduction in complications.

The face, as the communication basis for the first impression in people’s communication, is getting more and more attention, and people are no longer satisfied with the cure, leading to a steady rise in the number of beauty seekers in recent years. Given its unique characteristics, 2 critical considerations arise when repairing and reconstructing the face: ensuring the function and coordination of the 5 senses, and restoring facial esthetics. Consequently, the repair of facial soft tissue defects is both challenging and significant, representing a technical hurdle that plastic surgeons continue to confront.¹ Various methods are commonly employed for repair, including direct suturing, fractional resection, skin grafting, local flaps, expanded flaps, pedicled flaps, and free flaps.² Local flap repair is particularly effective when there is an adequate amount of soft tissue available, offering several advantages such as similarity in color and texture to the surrounding skin, the absence of new scarring in the donor area, flexibility in design principles, and enhanced surgical maneuverability. The invention and clinical application of the skin expander addresses the issue of insufficient local flap tissue. By expanding the excess skin through regular saline injections and adhering to the principles of flap design, the skin expander can facilitate the repair and reconstruction of facial soft tissue defects. This technique is applicable for repairing large benign facial lesions (eg, nevi, hemangiomas, scars, and so on) and has consequently emerged as one of the primary modalities for addressing large soft-tissue defects in recent years. In this article, we present the experiences of 5 patients who underwent repair of substantial facial defects utilizing expanding skin flaps.

METHODS

Patients

All the patients in the study gave informed consent for the treatment plan adopted and had been granted the right to use the patient’s likeness before the operation. We retrospectively reviewed 5 cases of repairing skin soft tissue defects of head and face using expanded flaps, which were performed between October 2018 and May 2021. The cohort included 3 male and 2 female patients, with ages ranging from 7 to 24 years, yielding an average age of 19 years. The area of the defects varied, with a maximum size of 8.5 cm by 6 cm and a minimum of 6 cm by 1.8 cm. All dilators were sourced from Guangzhou Wanhe Plastic and Reconstructive Materials Company, and disposable dilators were utilized. The total volume of intraoperative dilatation ranged from a minimum of 80 mL to a maximum of 220 mL, with the dilatation process completed over a period of ∼8 to 12 weeks.

TREATMENT

Preoperative Assessment

After conducting thorough preoperative examinations and rigorously assessing and excluding any surgical contraindications, we formulated relevant treatment plans tailored to the patients’ cephalo-facial defects. All patients underwent at least 2 stages of surgery, to ensure optimal therapeutic outcomes for their cephalo-facial soft tissue defects.

Surgical Procedure

Before stage I surgery, the appropriate placement of the expander and surgical incision, as well as the selection of an expander type suited to the patient (eg, kidney-shaped, columnar, or cylindrical), are determined based on the patient’s cephalo-facial soft tissue defects. The patient is anesthetized (general or local), and the skin, subcutaneous tissue, and fat layer are incised sequentially according to the preoperative marking lines. The soft tissue is dissected to the depth where the expander is placed to form a flap pocket. The cavity of the flap bag should be ∼0.5 to 1 cm larger than the expander to achieve the target range of expansion. Prepare a tunnel for the injection pot far away from the expander. The water injection port should be located at a location that facilitates percutaneous access. After inserting the expander, inject normal saline at 10% of the rated volume. After complete hemostasis, the subcutaneous tissue and skin are sutured in layers. After the operation, a negative pressure drainage tube is placed, and a pressure bandage is applied. Antibiotics can be used routinely for symptomatic and supportive treatment. Following a period of 24 to 48 hours, the negative pressure drain is removed. The stitches are removed after 1 week, after which the expansion is observed for any signs of leakage or displacement. If the expanded is confirmed to be placed in the correct position, the expansion process can begin. The speed and volume of water used during expansion should be monitored carefully to prevent excessive expansion and thinning of the skin. Expansion should be repeated every 2 weeks, with the entire process taking between 8 and 12 weeks. It is essential to maintain the expansion of the rated volume for a period of 2 to 3 months before stage II surgery. In advance of this, the design of the skin flap must be considered, taking into account the limitations of flap retraction and mechanical stretch-induced skin regeneration. These limitations typically restrict the expansion to the original area to a ratio of 2 to 3 times, with other factors also influencing the final outcome. The size of the flap should be designed to be ∼30% larger than the original defect area. A marking line should then be drawn along the border of the lesion, and the lesion should be excised according to this line. Subsequently, the expanded skin flap is transferred to the defect area, and a pressure bandage is applied after layered suturing.

RESULTS

A total of 5 cases were expanded, including complete expansion and excision of congenital hemangioma, giant nevus, and scar. In 1 patient, the buccal expander was removed due to infection and failed to be placed. Subsequently, the expansion flap obtained from the neck expander was repaired, resulting in a satisfactory outcome. Furthermore, the frontal expander of one patient was removed due to leakage. The expansion flap obtained from the remaining 2 expanders was then repaired, resulting in a satisfactory outcome. It is noteworthy that no other complications occurred in the remaining patients. In the remaining patients, no complications were observed during the placement of the expanders. All patients were duly changed at the appropriate time and underwent a further examination within 1 month of surgery. The flaps were all found to be viable without evidence of necrosis or infection. One patient exhibited evident incisional scar hyperplasia at the 6-month telephone follow-up, citing personal reasons for noncompliance with the scheduled follow-up. The remaining 4 patients participated in the follow-up program, following the provision of informed consent, and returned to the hospital for review at 6 months, 1 year, and 2 years postsurgery. The results of the postoperative period were deemed to be favorable, and the patients indicated that they were more satisfied with the appearance of the surgical result.

*Supplemental Digital Content, Table 1 (http://links.lww.com/SCS/H502).

CASE REPORT

Typical Case 1

A 24-year-old male patient presented with a congenital hemangioma measuring 10×4 cm² in size, extending from the right frontotemporal region to the right corner of the eye. A total of 270 mL of expansion was performed using 3 different expanders: a 70 mL renal expander, a 100 mL cylindrical expander, and a 70 mL cylindrical expander. These were placed in the right temporal, right preauricular, and right frontal regions, respectively. A leakage of the frontal expander was identified and removed during the third postoperative week. Over 3 months, a total of 220 mL of water was injected into the remaining 2 expanders, after which the expansion was continued for a further 3 months. This was followed by a second-stage surgical procedure. Following the excision of the facial mass, a 10×3 cm² expanded flap was harvested from the temporal region and advanced in a gliding motion, maintaining a position flush with the hairline in the region where hair was present. An additional 8×2.5 cm² expanded flap was harvested from the anterior ear and glided forward and upward, with the 2 flaps then connected to cover the defect and sutured in layers. All the flaps were viable. One year later, the corners of the eyes were loosened due to scar pulling, and the tails of the eyes were adjusted. The patient expressed satisfaction with the treatment result at 2 years postoperation (Fig. 1).

FIGURE 1.

A 24-year-old male with a expander placed preoperatively in each of the buccal and temporal regions (A). The preoperative lateral photograph clearly shows a lesion measuring 4×10 cm² (B). Complete resection of the lesion is visible 1 week after surgery (C). At 3 years postoperatively, partial scarring is visible on the face but satisfied (D).

Typical Case 2

An 18-year-old male patient presented with a large pigmented nevus on the dorsum of the nose, measuring ∼6.5×4.5 cm² and covering almost the entire dorsum of the nose. A 70 mL columnar expander was placed in the forehead, and 7 mL of saline was injected intraoperatively (prophylactic antibiotics were administered 1 wk postoperatively), followed by a total of 80 mL of water over the subsequent 3 months. Thereafter, continuous expansion was carried out for a further 3 months before the second stage of surgery. Following the excision of the pigmented nevus, a forehead flap based on the supratrochlear artery (STrA) was designed to be rotated to cover the resulting defect. The donor area was directly pulled together and sutured. Given that the defect involved the entire nasal dorsum, the pedicle of the flap was also used to cover the defect, and pedicle breaking was never performed subsequently. Two years following the initial procedure, the patient returned to the hospital for a follow-up appointment. When returning to the hospital, skin flap fat removal was performed under local anesthesia, and the bulging part of the pedicle was trimmed (Fig. 2).

FIGURE 2.

A lesion measuring 6.5×4.5 cm² is clearly visible on the nose before surgery (A). A expander was inserted subcutaneously to fully expand it (B). Two years postoperatively, complete excision of the lesion, red linear scar visible on the face without hyperplasia, and slight hypertrophy of the skin of the tip (C). postoperative result of trimming the skin of the hypertrophied tip at stage III (D).

Typical Case 3

A 24-year-old female patient presented with a congenital nevus of pigmentation involving the entire right upper eyelid and extending into the dorsal region of the nose. The nevus was observed to have an irregular black appearance and was ∼6×1.8 cm² in size. A 100 mL round expander was inserted into the right frontotemporal region of the patient at the outset of stage I surgery and inserted subcutaneously. Immediately following the surgical procedure, 10 mL of saline was injected into the patient’s right frontotemporal region. No postoperative complications, such as hematoma, occurred. Over 20 weeks, water was injected once every 2 weeks, with a cumulative total of 112 mL of water injected. The expander was removed before the commencement of the second surgical phase. The mass was then excised in its entirety along the periphery of the mass. Thereafter, a flap was designed by the principles of translocated flap surgery. This flap was then completely inserted into the right upper eyelid to reconstruct the defect in that region. The donor area was then sutured using a direct pulling technique. At the 3-month postoperative review, the flap was observed to have good survival, no obvious scarring, and a color and texture that was similar to those of the surrounding flaps. A 3-stage surgical procedure was contemplated to improve the mild ptosis of the right upper eyelid. The patient expressed satisfaction with the results of the postoperative period (Fig. 3).

FIGURE 3.

Preoperatively, the left forehead skin was fully expanded by placing a expander, and the lesion area was about 6×1.8 cm (A). The lesion was completely excised, and a translocation flap was inserted into the lesion location, and the expanded portion was directly pulled together and sutured (B). Three months after surgery, frontal scar is not obvious, red scar is visible in the right medial canthus and partially pulls the upper eyelid, which is slightly hypertrophied (C). At 8 months postoperatively, the medial canthus scar was significantly faded (D).

DISCUSSION

Common lesions affecting facial esthetics, such as pigmented nevi, haemangiomas, scarring due to burns or trauma, malignant tumors, etc, are still mainly treated by surgical excision.³ Commonly used repair methods include free skin graft, local flaps, free flaps, tipped flaps, and expanded flaps, each with its advantages and disadvantages.⁴ Free skin grafts are not limited by the distance and area of repair, but the scar left in the donor area affects the appearance. The pedicled skin flaps have a high survival rate due to the distal part of a blood vessel, but it is more complicated and needs to take into account the pedicle and blood vessels. Free flaps increase the surgical time and risk due to the need for vascular anastomosis. Localized flaps⁵ are effective but limited to smaller defects. Expanded flaps obtained with an expander and used for repair can solve the problem of insufficient tissue volume and are close in color and texture to the surrounding skin. Expanded flaps may be the current first choice for the repair of facial defects under conditions such as the patient’s ability to undergo 2 surgeries, a long treatment period, and transient changes in appearance.

The design of the dilatation flap is inextricably linked to the facial blood supply. The source arteries of the skin of the head and neck contain 10 terminal dermal vessels that converge to form the blood supply to the region.⁶ The source arteries give rise to branches or migratory continuations that become direct cutaneous arteries, which serve as the primary reference for axial flaps. The prevalence of indirect cutaneous arteries is a significant factor contributing to the viability of facial random-type flaps. Furthermore, the dilated cutaneous microangiogenesis with increased blood flow, which is essentially a flap delay phenomenon, has the potential to enhance the survival rate of the flap.⁷ The central region of the face represents an anastomotic communication zone between the internal and external carotid arterial blood supply systems. The dorsal nasal artery, which originates from the internal carotid system, and the medial canthal artery, which arises from the external carotid system, converge at the dorsum of the nose. In addition, the dorsal nasal artery possesses an anastomotic branch that is connected to the STrA.¹ The supraorbital plexus provides the connection among the 3 arteries that pierce the orbital rim, facilitating perfusion of the flap. It forms a vascular plexus with the surrounding cutaneous arteries, thereby ensuring a reliable blood supply to the forehead skin.⁸ The frontal skin flap is characterized by a high blood flow as a donor area, allowing for flexible utilization according to its anatomy while integrating the principles of random and axial skin flaps. Secondly, following the expansion of the skin, the cell gap is widened, the dermis and subcutaneous tissue are reduced, and the fat and muscle are also reduced, with the fat layer being the most affected.⁹ Therefore, there is no need to thin the skin flap when repairing periorbital defects. In one case, periorbital reconstruction was performed using a frontal expansion flap, with satisfactory results. Furthermore, the issue of venous return must be taken into account when the flap graft is expanded. It was determined that the average diameter of the STrA was 1 mm¹⁰ and the distance between the edge of the flap pedicle and the artery was at least 5 mm to ensure blood supply. In addition, other scholars¹¹ have reported that the supratrochlear vein lies medial to the STrA and is not in close proximity. The pedicle of the flap should be delineated with the STrA as the lateral boundary and the supratrochlear vein as the medial boundary. An appropriate width of 1.5 to 2.0 cm is recommended to ensure adequate blood supply and to minimize obstruction of venous return. In our department, the expander is placed in the subcutaneous plane when buried in the frontal region. Previous scholars predominantly recommended positioning the flap on the deep surface of the frontalis muscle. However, subsequent studies¹² have demonstrated that subcutaneous insertion can facilitate more efficient expansion of the skin, particularly in the forehead. In addition, subcutaneous insertion preserves and promotes the proliferation of a greater number of cutaneous vascular plexuses, thereby ensuring a more robust blood supply to the flap. This reduces the likelihood of infections and hematomas, which is beneficial for the restorative effect of the expanded flap. Consequently, the frontal expansion flap is typically the preferred option. The refinement of the design methodology throughout the repair process can mitigate the incidence of complications and enhance the survival rate of the flap.

During the expansion process, our department recommended that dilatation be conducted at a slow pace, with dilatation reaching 150% to 200% of the established dilator capacity. Thereafter, water injection should be ceased and the dilator retained in the patient for a period of 2 to 3 months before commencing the second stage of the procedure. It has been demonstrated that¹³ the maximum value of dilator pressure on the skin is within 200% of the dilator capacity, specifically during the initial and intermediate stages of dilatation. In addition, it has been observed that as the volume of injected water increases, the pressure decreases. Furthermore, it has been demonstrated that the longer the dilation period, the smaller the contraction rate of the dilated flap.¹⁴ Therefore, this can facilitate the continuous expansion of the skin and reduce the retraction rate of the expanded skin flap. Firstly, it improves the utilization rate of the expanded skin flap. Secondly, it effectively reduces skin tension and inhibits scar growth, resulting in better post-repair results.

In our case, 2 dilators were failed placement. Firstly, one of these was placed in the buccal region and subsequently removed due to infection. The patient was 7 years of age with a large nevus. In stage I surgery, expanders were placed in the cheek and neck, and the defect was repaired by an expanding flap in the neck after the buccal expander was removed due to infection. Wang et al¹⁵ proposed that young age and an excessive number of expanders are risk factors for a high incidence of infection. Wang et al⁶ demonstrated that the buccal region has a rich blood supply and is prone to expansion, but has a higher chance of infection. Azzi et al¹⁶ proposed the concept of the “tamponade effect,” which suggests that areas with dense bony structures, such as the forehead and scalp, are better able to encase expanders and form a tight space, reducing the incidence of hematoma. Conversely, areas without bony support, such as the cheeks, have a higher incidence of hematoma and an increased risk of infection. Furthermore, their analysis demonstrated that the nonsubcutaneous insertion resulted in a higher incidence of infection compared with subcutaneous insertion. In addition, the authors observed that buccal dilators were often placed on top of the SMAS fascia, which may also contribute to an increased risk of infection. Furthermore, the authors posit that the elevated incidence of buccal infections may also be associated with the proximity of the oral cavity and maxillary sinus. The human oral cavity is home to ∼700 species of microorganisms, which exist in a mutually reinforcing ecological balance. Any disruption to this equilibrium can result in pathological changes.¹⁷ Microbial translocation is one of the influencing factors, and translocation can be long-distance, that is, it occurs outside the oral ecological zone. The placement of dilators may also disrupt the balance of the oral ecological flora and create conditions conducive to infection, thereby contributing to the failure of dilator placement. Secondly, the proximity of the buccal region to the maxillary sinuses, where fluid accumulation is often associated with the common cold or rhinitis, may also increase the likelihood of infection following buccal dilator placement. In our experience, the age of the patient and the location and number of dilators placed should be considered to minimize the incidence of infection. If a dilator is to be placed in the cheek, the number of days of perioperative antibiotics can be increased, or a small amount of metronidazole can be added when injecting isotonic saline into the dilator,¹⁸ as the dilator has a penetrating effect and a local anti-infective effect on the surrounding tissue.

CONCLUSION

The authors posit that in cases where patients are amenable to multiple surgical procedures, a prolonged treatment regimen, and a brief “disfigurement period,” the expansion flap should be the primary option for the repair and reconstruction of extensive facial defects. Furthermore, a comprehensive understanding of cephalo-facial vascular anatomy can facilitate more rational flap design and expander placement, thereby enhancing the feasibility of facial expansion. The utilization of optimized repair methodologies during surgical procedures can also serve to reduce the incidence of complications, thereby enhancing the survival rate of the flap, ensuring patient satisfaction, and facilitating the attainment of superior repair outcomes.

Supplementary Material

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