FIGURE 45.1 The anatomy of the lateral scalp.

The most superficial layers of the scalp include the skin and underlying subcutaneous tissue, which in the lateral scalp is comprised primarily of the hair follicles. The hair follicles are an important landmark in the harvest of this flap. The temporoparietal fascia is found immediately deep to the hair follicles. The superficial temporal artery and vein and its anterior and posterior divisions are found within this layer. The frontal branch of the facial nerve also runs in this layer anteriorly over the zygomatic arch and extending toward the frontalis muscle. Deep to the temporoparietal fascia is the layer of loose areolar tissue, and deep to this lies the fascia of the temporalis muscle. The fascia of the temporalis muscle is a firm dense layer of connective tissue typically used in tympanoplasty for reconstruction of defects in the tympanic membrane. The temporalis muscle is found deep to this layer. Superior to the superior temporal line, the temporalis fascia becomes contiguous with the pericranium and the temporoparietal fascia becomes contiguous with the galea aponeurotica. The temporalis muscle fascia inserts inferiorly onto the superior border of the zygomatic arch.

The nutrient vessel of the TPFF, the superficial temporal artery, is one of the two terminal branches of the external carotid artery. After passing through the parotid gland, it is found immediately superior to the posterior aspect of the zygomatic arch, where it is identified prior to branching into its anterior and posterior components. The superficial temporal vein parallels the superficial temporal artery. In some cases, it may run posterior to the ear to drain into the postauricular vein, which can result in a shorter vascular pedicle.

HISTORY

Patients who are possible candidates for TPFF reconstruction of the cranial base will present with either an anticipated postablative or traumatic defect involving selected areas of the base of the anterior, middle, or posterior cranial fossa. For defects in these areas, the TPFF is best suited to providing a lining (such as an orbital exenteration cavity), a barrier (to separate the middle fossa dura from the sinonasal cavity), or a vascularized obliterative volume of tissue (as in a large mastoid cavity following revision cholesteatoma surgery with exposed dura). Patients who have had prior surgery that may have disrupted either the TPFF layer or the integrity of the superficial temporal vessels should be considered for a different reconstructive approach. Patients who will require a large volume of soft tissue to reconstruct the defect, such as a total maxillectomy and orbital exenteration, when it is desired to repair the entire defect, likewise should be reconstructed with a larger-volume flap such as a rectus abdominis, anterolateral thigh, or scapular free flap. A resection that may also include either a subtotal or total parotidectomy where the nutrient vessels may be sacrificed should force consideration of an alternative reconstructive option.

PHYSICAL EXAMINATION

The patient should be examined preoperatively to determine the suitability of using the TPFF for reconstruction. The nature of the defect, the volume of tissue required, the distance of the defect from the fulcrum of the pedicle, and the integrity of the donor sites should all be assessed. Careful inspection of the lateral scalp should be performed with special attention to detect well-healed scars. The superficial temporal artery pulse should be located and palpated. Any evidence of previous surgery in this area should raise the possibility of the need for an alternative plan for the reconstruction. Evidence of severe radiation changes in the soft tissue of the lateral scalp in patients with previous radiation therapy undergoing revision or salvage surgery should also be a contraindication to the use of the TPFF.

INDICATIONS

The temporoparietal fascial flap is indicated in the reconstruction of lateral and posterior defects of the skull base that require a vascularized layer of tissue to separate the intracranial contents from the extracranial contents. It is useful for defects in the midline skull base, the orbit, and the mastoid cavity. Its proximity to the recipient site as well as minimal donor site morbidity, including essentially an undetectable cosmetic defect, makes it a very useful flap for reconstruction of defects in these sites.

CONTRAINDICATIONS

Previous surgery in the lateral scalp that has disrupted the blood supply to this layer by injuring the superficial temporal artery and vein is a contraindication to the use of this flap. In addition, any concerns about the viability of the remaining skin overlying the craniotomy defect, particularly for middle cranial fossa surgery, should also raise some concern. Radiated skin or a diabetic patient would potentially not heal if the temporoparietal fascia were harvested.

PREOPERATIVE PLANNING

Stay updated, free articles. Join our Telegram channel

Join