The surgical resection methods for head and neck malignant tumors vary depending on the primary site and clinical stage (refer to the corresponding sections). The removal of primary lesions often leads to damage to the appearance of the head and neck as well as critical physiological functions such as breathing, phonation, and swallowing. As a result, the repair and reconstruction of head and neck defects constitute a vital component of surgical treatment for malignant tumors in this region.
Objectives of Repair and Reconstruction
The repair and reconstruction of head and neck defects aim to achieve both functional restoration and aesthetic reconstruction, while preserving or restoring crucial physiological functions such as breathing, phonation, and swallowing to improve the patient’s quality of life. Appropriate repair techniques also address dead spaces and surgical wound areas, protect critical cervical blood vessels, and reconstruct important anatomical structures such as the skull base. Additionally, reconstruction broadens the surgical options for intermediate- and advanced-stage head and neck tumors, allowing more patients to undergo effective treatment. Successful repair promotes primary wound healing and reduces surgical complications, thereby facilitating timely postoperative radiotherapy and/or chemotherapy. This contributes to better postoperative recovery and higher cure rates for the patients.
Principles of Repair and Reconstruction
Defects caused by head and neck tumor resection are often complex and may include isolated or combined deformities involving the skin, mucosa, large portions of soft tissue, or bone. Various repair techniques and materials are available in clinical practice, and selecting an appropriate method is critical. The principles guiding repair and reconstruction include the following:
Stepwise Approach to Repair
The principle of "simpler over complex and closer over distant" is emphasized. Repair methods should proceed from the simplest and most effective techniques to more complex approaches, with simpler options prioritized whenever possible.
Planning of Primary and Secondary Reconstruction
Reconstruction is ideally performed as a primary procedure immediately following tumor resection to minimize patient disability and reduce the length of hospital stay. For patients not suitable for primary reconstruction, a secondary reconstruction plan should be established.
Comprehensive Assessment
The requirements of the recipient site (the defect area) and the potential loss and complications at the donor site should be thoroughly evaluated. The surgeon's skills and preferences should also be taken into account to determine the most appropriate repair method.
Availability of Multiple Reconstruction Techniques
Backup repair methods should always be prepared in case the initial reconstruction technique fails or proves unsuitable.
Methods of Repair
A wide range of repair techniques and materials are currently employed in clinical practice, which can be categorized as follows:
Direct Approximation and Suturing
This method is suitable for defects with small surface areas where wound closure can be achieved with minimal tension.
Free Tissue Grafting and Transfers
Free grafting techniques include split-thickness, medium-thickness, and full-thickness skin grafts. Although technically simple and reliable, free skin grafting has various limitations, such as poor color and texture matching, contracture deformities at the recipient site, scarring at the donor site's periphery, and reduced durability. Additionally, free tissue transfers involve other types of tissues, such as fat, fascia, bone, nerves, and blood vessels.
Fat transfers is typically used for repairing lateral skull base defects.
Fascial transfers are commonly used for anterior skull base reconstruction.
Bone transfers are often employed to provide structural support for the anterior skull base or for the reconstruction of mandibular defects.
Nerve transfers are utilized for bridging defects in cranial nerves, such as the facial nerve or the recurrent laryngeal nerve.
Vascular transfers are used for vascular reconstruction in cases where the common or internal carotid artery has been resected.
Tissue Flap Reconstruction
The majority of post-surgical defects in head and neck tumors require tissue flaps for repair to achieve primary healing. Tissue flaps can be categorized into the following three types:
Local Flaps
Local flaps refer to tissue flaps adjacent to the defect area. These are the best option for repairing small to medium-sized skin defects because they provide well-matched skin. Local flaps can be further subdivided into:
Random-Pattern Flaps
These rely on blood supply from the subdermal vascular plexus. To minimize the risk of flap necrosis, the length-to-width ratio of the flap must not exceed certain proportions, such as 4–5:1 for the face and 1–2:1 for the trunk.
Axial Flaps
These are vascularized by their intrinsic axial blood vessels. The survivable length of the chosen flap depends on the length of the vessels within the flap rather than the flap’s width. Axial flaps can also be designed as pedicled island flaps with vascular pedicles, such as retroauricular island flaps, submental flaps, nasal septal mucoperiosteal flaps, superficial fascial flaps, and platysma flaps.
Regional Flaps
Regional flaps are composed of tissues such as skin, fascia, muscle, and bone located at a greater distance from the surgical site. These flaps, supplied by well-defined axial vessels, have advantages such as a large range of transfer, high survival rates, and strong resistance to infection. Based on their composition, regional flaps include musculocutaneous flaps, osteomusculocutaneous flaps, myoperiosteal flaps, and osteomyocutaneous flaps. Among these, musculocutaneous flaps, which are thick and reliable, are a primary method for reconstructing head and neck defects. Commonly used musculocutaneous flaps in head and neck reconstruction include the pectoralis major flap, latissimus dorsi flap, lower trapezius flap, sternocleidomastoid flap, and submental flap.
Free Tissue Flaps
Free tissue flaps consist of skin, fascia, muscle, bone, or portions of the digestive tract obtained from areas distant from the surgical field. These flaps are transferred to the defect area through microsurgical vascular anastomosis, where the vascular pedicle of the donor site is connected to the recipient area. Compared with local and regional flaps, free tissue flaps offer advantages such as the ability to provide a larger tissue area, greater flexibility in design and transfer, and a wider range of available tissue options. However, disadvantages include differences in the properties of skin between the donor and head/neck areas, the need for surgical techniques under a microscope or magnifying loupe, and higher technical demands. Widely used free tissue flaps include the radial forearm free flap, free rectus abdominis myocutaneous flap, free jejunal flap, and free fibula flap.
Artificial Materials
Artificial materials can be considered when autologous tissue is insufficient or difficult to use for repairing large defects, such as significant anterior skull base defects, orbital content defects, mandibular defects, or major vascular defects. Artificial materials are also an option when autologous tissue repair involves complex procedures or prolonged operating times that may not be well-tolerated by the patient. Examples include titanium mesh for anterior skull base reconstruction, titanium plates for mandibular reconstruction, artificial blood vessels for carotid artery repair, and prosthetic implants for orbital reconstruction.