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Surgery of the parotid gland accounts for 1–2% of iatrogenic induced facial nerve injuries. In particular, after primary parotid surgery temporal and permanent facial nerve palsies occur in 10–66% and 2.5–8% of cases, respectively. However, risk of facial nerve injury increases with (1) extend of excision, (2) surgical resection of tumour recurrence, and (3) salvage surgery. Therefore, meticulous dissection and detailed knowledge of anatomic landmarks are crucial to prevent facial nerve damage. It is of utmost importance to first identify the tragal pointer of the auricle, the posterior belly of the digastric muscle and the tympanomastoid suture line as anatomic landmarks for safe dissection of the extratemporal, main trunk of the facial nerve. Thereafter, the branches of the facial nerve can be safely dissected using surgical loupes under neuromonitoring. The marginal mandibular branch, running along the body of the mandible, is at the most risk for injury during parotidectomy and even at higher risk when performing a level Ib neck dissection. Particularly for level Ib neck dissection, the topography of the marginal branch and the fact that it crosses superficially the facial artery within the plane of the platysma needs to be kept in mind. The marginal mandibular branch, in turn, can be easily identified 1–2 cm superiorly to the lower edge of the mandible where the facial artery curves upwards within the groove of mandible’s body.

One of the essential skills of a reconstructive surgeon is not only in the ability to properly raise the flap but also in a competent exposure of recipient vessels. The raised flap will be irreversibly lost if the recipient vessels are unsuitable for microsurgical transfer to the required area. That is why the recipient exposure skill must be mastered together with the free flaps harvesting. Training the proper exposure of recipient vessels includes the ability to work with soft tissues, neurovascular bundles, and recipient bed preparation. This chapter describes the basic techniques for working with normal vessels: in clinical practice, various defects are possible at the recipient site. So, it is important to remember that each case is individual and the surgeon must be able to manage with unusual situations at the expense of his knowledge and surgical savvy. We describe the techniques of exposure of the workhorse recipient vessels: carotid artery and jugular vein, facial artery and vein, and internal mammary vessels.

The nasolabial fold (NFL) is a natural contour, which belongs to the middle third of the face. The NFL becomes an important aesthetic problem, when with age, it becomes more prominent due to several factors such as loss of soft tissue volume, cutaneous atrophy, less elasticity of the skin, loss of fat malar, and musculature of the face.

The facial artery and vein, frequently utilized in microvascular head and neck reconstruction, have traditionally been exposed via limited neck dissection or similar neck exploration techniques. However, when neck dissection is not required and/or increased superior pedicle reach is required, these vessels are amenable to isolation via a small aesthetically favorable incision just below the inferior mandible border at the facial notch. The technique described in the following chapter allows for facile vessel access and isolation with minimal morbidity and negligible risk to adjacent neural structures.

The lips surround the mouth which is the entrance into the gastrointestinal system. The oral cavity provides the ability to eat, drink, and speak. Digestion begins in the mouth through mastication and the action of salivary enzymes. The musculature controlling the mouth is complex and interdigitating, making their repair and reconstruction challenging. The muscles which seal the oral cavity, elevate, or depress the lips are described. Motor innervation of these muscles is provided by branches of the facial nerve (CNVII). Sensory innervation is provided by branches of the trigeminal nerve and cervical nerves. The facial artery, a branch of the external carotid, supplies this region.

The following chapter is a brief overview of the lateral craniofacial anatomy that will be relevant to subsequent clinically related chapters. It starts with an overview of the bone and soft tissue to put the anatomy in context followed by a more detailed description of the zygomatic-maxillary region, temporal region, and mandibular region. Within each region the basics of the boney anatomy are described followed by a closer look at the important soft tissue structures such as the facial vessels, facial nerve, parotid gland, lymph nodes, and the temporomandibular joint. The musculature associated with each region, in particular the temporal and mandibular regions, is described with respect to the underlying bone, relationship to the other soft tissues, and actions on the joint.

In 1989, Bozola et al. (1989) published the first anatomic description of a posterior buccinator myomucosal flap based on the buccal branch of the internal maxillary artery. Different types and technical modifications of the buccinator myomucosal flap have been described reflecting its versatility for numerous reconstructive applications (Bozola et al. 1989; Vaira et al. 2017; Jowett et al. 2017; Ayad and Xie 2015; Rahpeyma and Khajehahmadi 2015a, 2013; Franco et al. 2014; Massarelli et al. 2013; Zhao et al. 1999; Pribaz et al. 1992; Carstens et al. 1991). Based on a dense vascular network between the facial artery and the internal maxillary artery there are variations as the posteriorly based flap (buccal branch of the internal maxillary artery, which enters its lateral aspect just anterior to the pterygomandibular raphe), the superiorly and antero-inferiorly based flaps with direct (facial artery musculomucosal [FAMM] flap) or retrograde flow (reverse-flow facial artery buccinator flap), and the island flap (a vascular island variant of FAMM flap, in which the facial artery and vein are skeletonized) (Bozola et al. 1989; Vaira et al. 2017; Jowett et al. 2017; Ayad and Xie 2015; Rahpeyma and Khajehahmadi 2015a, 2013; Franco et al. 2014; Massarelli et al. 2013; Zhao et al. 1999; Pribaz et al. 1992; Carstens et al. 1991).

The external carotid artery (ECA) arises from the common carotid bifurcation at the C4 vertebral level. A more proximal or distal origin can occur. Variants of the level of the carotid bifurcation are described in Chap. 2. These variants also involve indirectly the origin of the ECA. The ECA may originate directly from the aortic arch. The ECA lies in the carotid space, initially medial and anterior to the internal carotid artery (ICA), seldom lateral to it. More cranially, the ECA runs anterolateral to the ICA. The jugular vein lies posterolateral to the ICA and ECA. The ECA is covered partially by the sternomastoid muscle and crossed by cranial nerve XII. The vagus nerve lies medially. During its course, the ECA gives off several branches. Near the mandibular condyle within the parotid gland, it divides into its terminal branches (Figs. 3.1 and 2.1).

Epistaxis is common. At least 60% of us will have episodes of nose bleeding at some time [2]. These occur with peak incidences in children ( 50 years). Only 6% of episodes require medical treatment, and these are usually in the older age group. Bleeding can arise from veins, arteries or arterialised veins (e.g. associated with a vascular malformation or an arteriovenous shunt). Most episodes are idiopathic, though epistaxis in adults is frequently associated with systemic hypertension and other medical comorbidities.

The vestibule belongs to the oral cavity – it is bounded internally by the teeth and externally by the soft tissues of the lips and cheeks. The vestibule provides access to the teeth and their supporting structures from the labial and buccal aspects and thus is important in clinical dentistry for carrying out diagnostic, operative, and surgical interventions. This chapter illustrates the anatomical structures of the vestibule and cheeks including their function and clinical significance.

The floor of the mouth, also called “diaphragma oris,” includes the soft tissues between the medial aspect of the mandibular body and the hyoid bone. As such, it represents the inferior border of the oral cavity. Four of the six large salivary glands are associated with the floor of the mouth, i.e., the sublingual and submandibular glands. The main muscles contributing to the floor of the mouth include the mylohyoid and the geniohyoid muscles. The major arterial supply to the floor of the mouth is provided by the sublingual and submental arteries.

Surgical approaches may be classified according to specific anatomic target areas, which in turn are associated with specific reconstructive idiosyncrasies. In addition, each approach creates a corridor with adjacent structures that may have different functions and significance. In the median skull base, EEAs can extend caudally to the level of C2 and anteriorly to the level of the posterior wall of the frontal sinus [1, 2]. Consequently, EEAs to the median skull base (i.e., sagittal plane) can be classified into six distinct corridors: transfrontal, transcribiform, transplanum, transsellar, transclival, and transodontoid [3]. Use of specific reconstructive techniques is contingent upon many factors aside from the corridor and target area: size and shape of the skull base defect, the condition of the surrounding bone and remaining dura, whether a CSF leak was encountered intraoperatively or not, the nature of the CSF leak encountered (high or low flow), extent of communication between the nasal and intracranial cavities, anticipated postoperative intracranial pressure (ICP), the nature of any lesion resected, patient comorbidities (e.g., diabetes mellitus, Cushing’s disease, immunosuppression), prior sinonasal surgery, status of the nasal septum and lateral nasal wall, history of previous surgery or radiation therapy, and the anticipated need for adjuvant therapies (i.e., irradiation or chemotherapy).