V-Y Advancement Flap in Mid-Temporal Defect Reconstruction After Mohs Surgery

Introduction

Overcoming the unique anatomical challenges posed by mid-temporal defects due to Mohs micrographic surgery treatment of various skin cancers can be difficult. Additionally, the decision-making process in selecting the most appropriate approach to achieve functional and aesthetic outcomes can require analytical reasoning. The vulnerability of the temporal branch of the facial nerve becomes relevant when surgical procedures are conducted in proximity to its most superficial region, just over the zygomatic arch [1]. We report a 68-year-old man who presented with a 4.2-cm invasive, well-differentiated squamous cell carcinoma with rapid growth and poorly defined borders in the left mid-temporal region. This tumor was treated with Mohs micrographic surgery and cleared in 5 stages. The use of the local flaps reconstructive technique was used to optimize patient outcomes.

Case Report

A 68-year-old man presented with a 4.2-cm invasive, well-differentiated squamous cell carcinoma with rapid growth and poorly defined borders in the left mid-temporal region (Figure 1). This tumor was treated with Mohs micrographic surgery and cleared in 5 stages. The final defect measured 4.3×4.4 cm (19 cm2), invading to the depth of the fascia (Figure 2).

The V-Y advancement flap is a reconstructive surgical technique designed to address tissue defects while preserving a direct vascular connection with the donor site [2]. Preoperative planning included precise markings to delineate the donor and recipient sites (Figure 3). An incision was made to outline the flap island, followed by dissection to delicately create the flap, while leaving a deep pedicle containing the vascular supply, to ensure optimal flap viability. The flap was elevated from the surrounding tissues and transposed to cover the defect without inducing tension. Fixation was achieved through deep sutures followed by epicuticular sutures (Figure 4).

Postoperatively, the patient was closely monitored for signs of compromised blood supply to the flap. Immobilization and elevation were implemented to facilitate healing. The patient presented for a follow-up appointment at our clinic 2 weeks after the surgical procedure. Notably, there was no observable blanching of the tissue covering the repaired wound, indicating adequate vascularization of the mid-temporal defect. A thorough evaluation at the 10-month postoperative follow-up revealed a well-healed wound with an acceptable cosmetic appearance (Figure 5).

Discussion

The vulnerability of the temporal branch of the facial nerve becomes relevant when surgical procedures are conducted in proximity to its most superficial region, just over the zygomatic arch. If any branches of the nerve are transected anterior to the external canthus, complete regeneration often occurs, leading to the restoration of full facial movement; however, as the surgical site approaches the preauricular area, the likelihood of spontaneous regeneration and regain of function diminishes.

In terms of Mohs micrographic surgery to the temporal area, the region with the highest mobility lies in the temporoparietal fascia that covers the temporalis fascia. At the temporal line, the galea adheres to the pericranium, resulting in reduced scalp mobility; to enhance mobility in this region, carefully dividing these attachments is advised [1].

For small defects, both second intention and primary closure methods are applicable. However, in the case of larger defects or those encompassing multiple anatomic subunits, these approaches become less advantageous. Considerations for repair on this case include closure by secondary intention, allografts, full-thickness skin grafts, local and regional flaps, tissue expanders, and, for very large defects, free tissue transfer.

For large temporal defects, primary closure may not be feasible, due to the limited elasticity of skin in this region. As such, reconstructive techniques, including local flaps, skin grafts, or a combination of these approaches, can be considered. Secondary intention can be advantageous for concave sites, such as the temple; however, in this case, it was not used, due to the large size of the defect and risk of wound contracture distorting the lateral eyebrow [2].

The choice between local flaps and grafts is influenced by factors such as the size and depth of the defect, the availability of nearby healthy tissue, and the patient’s overall health. Additionally, considerations for minimizing postoperative morbidity, optimizing cosmetic results, and achieving timely wound healing are essential.

Skin grafts can be employed to cover large defects where local flaps may not be suitable. Split-thickness or full-thickness grafts can be harvested from donor sites, such as the retro auricular area, and then are carefully placed and secured over the surgical defect. While grafts can lack the same color and texture match as local flaps, they are valuable options for coverage in certain situations.

Local flaps mobilize adjacent tissue to cover the defect; their selection depends on the specific anatomical characteristics of the temporal area. For instance, a transposition flap may be used to transpose adjacent tissue overlying normal skin into the defect, while an advancement flap involves moving tissue forward to close the defect. These techniques allow for the restoration of the natural contours of the temporal region. Local flaps offer advantages in the reconstruction of forehead and temporal defects, enabling the replacement of the damaged tissue with a visually similar substitute. These flaps have a minimal complication rate of 3.4% [3]. When designing local flaps for the forehead, it is imperative to adhere to certain principles, including the use of broad bases, extensive undermining, and the judicious use of electrocautery.

In the present case, a V-Y advancement flap was selected to transpose the lower cheek tissue reservoir upward, preserving cosmetic units of the mid-face. The technique involves advancing a broadly based triangular flap of skin toward the defect while maintaining its vascular supply. The “V” shape is incised, and upon advancement, the tissue is sutured into a “Y” configuration. Both the benefits and limitations of this closure must be taken into consideration.

One drawback is the potential for flap tip necrosis if the vascular supply is compromised. Excessive tension at the flap base can lead to wound dehiscence or standing cone formation, necessitating further revision. In certain locations, tissue laxity can be insufficient for adequate mobilization, restricting flap advancement and limiting its effectiveness. Moreover, improper flap design or excessive undermining can lead to contour irregularities, scarring, or distortion of nearby anatomical structures.

Despite limitations, V-Y advancement flaps are particularly useful for areas requiring minimal tension closure. They are an excellent consideration for the reconstruction of sites such as the mid-temporal region in which there are concerns about large size and closure of an area containing multiple anatomical subunits. Its versatility makes it a valuable option in reconstructive surgery, offering solutions for complex tissue defects across various anatomical regions. The success of the procedure relies on meticulous preoperative planning, precise execution of flap elevation and transposition, and vigilant postoperative care to optimize both the flap viability and functional restoration.

Conclusions

This case represents the selecting of an ideal closure technique for a large mid-temporal defect after Mohs surgery, driven by the inherent limitation of skin elasticity in the temporal region and the imperative to achieve both an aesthetic appeal and functional restoration. Furthermore, a V-Y advancement flap to reconstruct a large mid-temporal defect preserves functional and aesthetic elements. The success of this technique depends on the maintenance of flap viability through careful flap planning, dissection, and vascular pedicle preservation.