Reconstructive Options

The surgeon's choice of approach must be communicated to anesthesia and operating room personnel prior to the patient entering the operating room. The anesthesiologist should be instructed on whether a nasotracheal or orotracheal intubation is preferred and, if the latter, on what side of the mouth should the tube be taped, or if the surgeon plans to stabilize the tube in the midline with a Crowe-Davis mouth gag or similar instrumentation. Endotracheal tube placement becomes less important if the surgeon plans to convert to a tracheostomy early in the operation for the purposes of improving access to the tumor and/or post-operative airway control during resolution of edema. Common positions around the operating table during transoral approaches for the surgeon, scrub nurse, and anesthesiologist are illustrated in Figure 5, with the surgeon positioned above the patient's head for transoral approaches, and at the patient's side for external approaches, as in Figure 6.

If the reconstructive options include the possibility of a scapular or latissimus dorsi free flap, a beanbag must be placed underneath the patient's torso and hips in

Figure 5 Positioning around operating table of nasally intubated patient, with anesthesiologist above patient's head.
Figure 6 Optimal positioning around operating table of patient intubated via tracheostomy, with anesthesiologist at patient's feet.

order to rotate and stabilize them in a lateral decubitus position during the reconstructive phase of the procedure (Fig. 7). In addition, if the reconstructive team prefers to be seated while performing a microanastamosis, it is prudent to position the patient's head at the normal foot of the operating table which, in most operating theaters, allows sufficient room under the table near the patient's head and neck for the surgeon's legs and chair to be positioned comfortably.

For longer extirpative cases and all those in which a plastic and reconstructive team will scrub in after tumor resection, the patient should be fitted with sequential compression devices on their lower extremities, unless a fibular free flap or skin graft from a thigh donor site is needed. It is also prudent to have a urinary drainage catheter in place, and an arterial line is useful if a modest degree of patient hypotension is desired. The authors have found that such modest hypotension, plus placing the patient in a mild degree of anti-Trendelenburg to diminish the size of the neck veins, speeds the extirpation.

Surgical instrumentation for an external approach to an oral cavity lesion basically utilizes the same instruments as for a standard neck dissection, plus the addition of malleable retractors for visualization of recesses of the oral cavity and bone dividing instruments, usually an air driven drill with a side cutting burr or an oscillating saw. In cases for which an osteotomy is anticipated, the reconstructive surgeon's choice of a mandibular plating system must be available. Instrumentation for transoral access is much simpler, essentially the same as that for uvulopalatopharyngoplasty,

Neck Dissection Level Scar

Figure 7 Defect after excision of T4N2A tumor of lip and buccal mucosa (involvement of cheek and upper neck skin) with synchronous T1 primary of FOM; note anterolateral neck dissection; repaired with latissimus dorsi free flap, providing intraoral and cheek resurfacing. Abbreviation: FOM, floor of mouth.

Figure 7 Defect after excision of T4N2A tumor of lip and buccal mucosa (involvement of cheek and upper neck skin) with synchronous T1 primary of FOM; note anterolateral neck dissection; repaired with latissimus dorsi free flap, providing intraoral and cheek resurfacing. Abbreviation: FOM, floor of mouth.

with the addition of periosteal elevators and drills when needed. The most commonly utilized instruments are illustrated in Figure 8.

Transoral Approach

A transoral excision is feasible for most T1 oral cavity or oropharyngeal malignancies, and for many T2 lesions (Table 1) (1-4,10-12). In addition, some portion of the resection of larger oral lesions is usually accomplished transorally, commonly the anterior margins of an extirpation, supplementing the lateral and posterior exposures afforded by a transcervical access. For lesions of the roof of the mouth and upper alveolar arch, the surgeon is usually positioned at the patient's head, with the patient in a Rose position as for uvulopalatopharyngoplasty; the orotracheal tube is stabilized in midline, and the tongue retracted inferiorly by a Crowe-Davis or similar mouth gag (Figs. 9 and 10).

Tumors of the buccal mucosa and lower half of the oral cavity are also accessed via a transoral route, but with the surgeon and assistant positioned at the sides of the patient's head and shoulders. In such cases, the surgeon should be on the side opposite the tumor, as visualization is progressively compromised with more posterior locations in the oral cavity and it is easier to visualize the proposed posterior margins from the contralateral side. Indeed, the surgeon must be able to visualize well around the periphery of the tumor, and be confident of access to tissue planes deep to the tumor as estimated by preoperative palpation. Computed tomography (CT) or magnetic resonance imaging (MRI) contrast enhanced studies can help delineate deep tumor extensions (13,19).

Transoral access for even small tumors is sometimes not feasible in patients with trismus, macroglossia, or similar impairments to an adequate transoral exposure. Though the standard overhead lights of surgical theaters can usually afford reasonable

Figure 8 Instruments commonly utilized in a transoral resection of a tumor of the oral cavity.

visualization of intraoral structures, particularly anteriorly placed ones, most surgeons prefer headlights to assure adequate illumination of posterior or deep-tumor margins. Margins of at least 1-cm around all visible and palpable tumor is prudent, plus a further 3-5 mm is ideal for frozen-section analyses. The surgeon should indicate the tumor side margin with methylene blue, so the pathologist knows which is the "true" margin. A frozen-section control markedly decreases the necessity of secondary procedures for positive margins evident on a permanent section study.

Depending on size, most defects resulting from transoral tumor resections can be either closed primarily, allowed to granulate over a period of weeks, or be resurfaced with a split-thickness skin, dermal graft, or allograft such as Alloderm TM (Fig. 11) (1,3,5,12,17). Unfortunately, if 1-cm margins are obtained around a 1cm2 tumor, the resultant defect is 9 cm2 which may cause significant dysfunction, particularly at the tongue-FOM junction. In cases with the potential for significant scar contracture with tethering of adjacent structures, flap reconstruction may provide improved functional outcome and prevent dysarthria.

Post-operative management of these patients depends on the size of the defect and whether a graft has been placed, and in the latter case, whether such graft has been quilted into place or secured by a bolster. For primary closures or wounds allowed to granulate, a post-tonsillectomy regimen suffices, but for larger surface areas covered with skin grafts, the patient may need to remain nasogastric-tube dependent for five

Hard Palate Resection

Figure 9 Illustration of transoral view of hard and partial soft palate tumor; note location of greater palatine artery and vein, on which palatal island flap is based for local reconstruction after tumor resection.

Palatal island flap

Greater palatine artery & vein

Supratonsillar fossa

Palatoglossal arch

Palatine tonsil

Palatopharyngeal arch

Figure 9 Illustration of transoral view of hard and partial soft palate tumor; note location of greater palatine artery and vein, on which palatal island flap is based for local reconstruction after tumor resection.

Hard Veins After
Figure 10 Transoral view of hard and partial soft palate defect after resection of a polymorphous adenocarcinoma of a minor salivary gland; note Dingman retractor stabilizes the endotracheal tube, and retracts tongue inferiorly and cheeks laterally.
Hard Palate Resection
Figure 11 Intra-operative view of defect from transoral excision of superficial T2 anterior FOM and adjacent mandibular alveolar arch (periosteum not penetrated by tumor), defect closed with dermal graft stabilized by a bolster. Abbreviation: FOM, anterior floor of mouth.

to seven days. Most patients are prescribed post-operative intravenous antibiotics for the first 24 hours, and, thereafter, liquid oral antibiotics for one week, supplemented by saline and hydrogen peroxide combination mouthwashes.

Midline Glossotomy

The midline glossotomy is a combination of the transoral approach with a transcervical approach and can be performed either with or without a midline mandibu-lotomy which is usually necessary for lesions of the posterior mobile tongue or adjacent oropharynx (1,3,12,15). This procedure is accomplished with the surgeon and assistant positioned on opposite sides of the patient's neck. Although there are many options for incision placement for the ''lip split'' (Fig. 12), in the authors' opinion, the best cosmetic outcome is achieved via a stairstep incision through the lower lip; the stairstep begins at the vermillion border to break up any scar contraction that would later cause a notch in the lip, and then curves around the chin to make the skin incision conform with that soft tissue block of the face.

The mandible may also be divided in a stairstep fashion, halving the distance between the upper and lower borders with the horizontal portion of the osteotomy, while staying below the tooth roots in a dentulous patient (Fig. 13). Prior to mandibular division an appropriate plate should be fitted with bicortical screws at the lower border of the mandible. In the dentulous patient an additional plate with monocortical screws is place above the horizontal bone cut to function as a tension band. The plates are then removed and placed on the back table while mandibulot-omy is performed. At the end of the procedure, the plates can then be rapidly

Figure 12 Neck incisions for lower facial ("cervical") degloving, placed two fingerbreadths below inferior border of mandible in its mid portion, closer to mandible near midline, avoiding damage to marginal mandibular nerve; subsequent undermining affords exposure for mandi-bulotomy, lymphadenectomies.

Figure 12 Neck incisions for lower facial ("cervical") degloving, placed two fingerbreadths below inferior border of mandible in its mid portion, closer to mandible near midline, avoiding damage to marginal mandibular nerve; subsequent undermining affords exposure for mandi-bulotomy, lymphadenectomies.

replaced, with assurance of reformation of the preoperative dental occlusion and chin contour. It is usually necessary to remove at least one of the incisor teeth to perform the osteotomy. If sharp bony edges remain after osteotomy, these edges should be rounded with a round burr to prevent trauma on the incision line post-operatively.

Dissection through the anterior FOM is kept strictly in the midline, avoiding damage to Wharton's ducts, and the possibility of submandibular obstruction and infection. The tongue is then divided along the midline raphae which is a fairly avascular plane. Keeping the incision in the midline avoids all significant nervous and vascular structures and will minimize any muscular dysfunction. This approach is carried as far posteriorly as needed to provide access to the posterior tongue, tongue base, or posterior pharynx. On closure the tongue is repaired with deep and superficial absorbable sutures.

Lip Split with Cheek Flap and Mandibulotomy

The traditional and still most commonly applied approach to advanced lesions of the oral cavity is the lip/chin split incision which is connected with the ipsilateral neck incision and combined with a either mandibulotomy or mandibulectomy (Figs. 14 and 15). This allows mobilization and retraction of the entire cheek, posterior mandibular segment and upper neck flap to expose the oral cavity. The lip split is accomplished in an identical fashion to that previously described for the

Figure 13 Lower facial degloving for T4 of anterior FOM that penetrated mandibular symphysis; note upward retraction of chin and lip, and anterior and inferior retraction of tongue, plus lymphadenectomies of levels I and II bilaterally (no positive nodes). Abbreviation: FOM, anterior floor of mouth.

midline glossotomy as described above. From the chin the incision curves posteriorly to connect with the upper limb of the neck incision which should be at least two fingerbreadths below the mandibular body to avoid injury to the marginal branch of the facial nerve. This incision can usually be placed in a natural skin crease and carried posteriorly and upward to the mastoid tip for maximal exposure.

Lymphadenectomy is usually accomplished first, facilitating access to the under surface of the mandible and subsequently the tumor through the submandibular and submental triangles, with preservation of the hypoglossal and/or lingual nerves when feasible. Intra-operative hemostasis is obtained in a routine fashion, but it is optimized by infiltration of a 1:100,000 or 1:200,000 epinephrine solution (the latter if greater than a 15-mL infiltration is anticipated in an average sized adult) along the anticipated resection lines, plus ligation of arteries that feed the resection area such as the ipsilateral lingual artery for a hemiglossectomy.

Figure 14 Lip/chin split extension of neck incision; note bridging plate and corresponding drill holes designed prior to bony resection, facilitating reconstitution of mandibular contour; stairstep osteotomy, positioned anterior to mental foramen, with preservation of the canine tooth.

To access a large FOM or mobile tongue tumor, the stairstep osteotomy is placed either near the midline after removal of one of the incisor teeth (Fig. 14). For more posterior lesions the osteotomy is placed more lateral, just anterior to the mental foramen, preserving the mental nerves to avoid post-operative lip numbness. Low profile plates should be fashioned and placed/removed prior to the osteotomy as described previously to ensure preservation of dental relationships.

Should the mandible be involved by tumor, and bone resection is anticipated, the osteotomy should be placed to allow at least a 1- to 1.5-cm tumor-free margin on the mandible. The inferior alveolar nerve almost will always be sacrificed in this situation. Application of an appropriately shaped bridging plate prior to the bony resection is mandatory (Fig. 15). If resection of the entire ramus is anticipated, drill holes are placed in the mandible distal to the resection, and a new temporomandibular joint is fashioned from a preformed metal plate with a smooth ball on one end that will fit in the glenoid fossa, a costal cartilage and rib graft, or a free flap transfer.

In closing a lip-split defect, it is crucial to approximate the oral mucosa, orbicularis muscle and skin planes in three separate layers, and to carefully align the stairstep incision at the vermillion border. Nasogastric feeding for 7-10 days

Mouth Radical Resection

Figure 15 Lip/chin split, cheek rotation and segmental mandibulectomy for T4N2B of ret-romolar trigone and adjacent FOM; note metal bridging plate for attachment of fibular free flap, and radical neck dissection (spinal accessory nerve, internal jugular vein and sternocleidomastoid muscle all involved with extracapsular extension of metastases). Abbreviation: FOM, anterior floor of mouth.

Figure 15 Lip/chin split, cheek rotation and segmental mandibulectomy for T4N2B of ret-romolar trigone and adjacent FOM; note metal bridging plate for attachment of fibular free flap, and radical neck dissection (spinal accessory nerve, internal jugular vein and sternocleidomastoid muscle all involved with extracapsular extension of metastases). Abbreviation: FOM, anterior floor of mouth.

should be anticipated, and if a longer period of time is desired, a percutaneous gastrostomy (PEG) is preferred (i.e., better tolerated) by most patients. If such is planned, the PEG should be placed prior to the sterile preparation and draping for the head and neck tumor resection, to avoid intra-operative contamination of a chest or abdominal flap donor area.

Degloving Approach to the Oral Cavity

The term "degloving" is applied to oral cavity procedures which utilize neck or mucosal incisions to access the tumor, with or without a concominant lymphade-nectomy, without the necessity of a chin or lip incision. Previously, it has implied that the mandible was not divided, as in prior decades mandibulotomy was always performed after lip split and lateral cheek mobilization. However, upward retraction of the cheek and chin soft tissues after extensive undermining via a "cervical degloving," often performed bilaterally, can afford adequate room for a mandible split or resection. The lateral and inferior rotation of the proximal segment of the mandible without a lip/chin split in the authors' hands, is now the most common access for larger oral cavity tumors (Figs. 12 and 13) Table 2.

The more commonly utilized "degloving" procedure is a unilateral or bilateral transcervical approach to a mid to lower oral cavity neoplasm such as of the FOM, tongue or alveolar arch. The initial cut is basically the upper limb of a Schobinger or "apron" type of neck incision, crossing the midline below the chin in a gentle curve to

Table 2 Selection of Surgical Approach to Oral Cavity Tumor Based on Tumor Size and Location

Surgical approach

Tumor size

Location

Selected T2 or T4a

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