Traditionally, facial rejuvenation techniques have involved repositioning of portions of the superficial musculoaponeurotic system (SMAS) and skin. In the neck the SMAS blends with the platysma fascia to form a continuous sheet.³ Here, signs of cervicofacial aging are initially manifest as faint vertical platysmal bands overlying the thyroid cartilage and hyoid. These then progress to longer, more pronounced bands as more support is lost from the retaining ligaments and the platysma descends further.⁴ The laxity of the platysma causes a cervical obliquity, which is compounded by supra- and subplatysmal fat deposits. Subplatysmal fat can exacerbate the development of cervicomental angle obliquity. Submandibular gland ptosis may contribute to cervical fullness as well, supplying bulk laterally, below the angle of the mandible. The end result of these processes is a neck with a prematurely aged appearance.

Indications

Indications include young patients with a prematurely aged neck, or patients with the neck as a prominent aspect of facial aging. Other indications include those patients undergoing other aesthetic facial surgical procedures which otherwise accentuate the neck laxity.

Submandibular fullness results from increased glandular ptosis as muscular and fascial support of the gland weakens or glandular hypertrophy. SMAS plication in rhytidectomy or platysmal suspension may indirectly address this fullness because these techniques reestablish fascial support, but they have not proven helpful long term. However, residual submandibular gland ptosis often persists after platysmal, cervical fat, and skin laxity surgical objectives have been met, and tightening of the overlying tissues may accentuate the deformity.

Patients with lesser degrees of submandibular gland fullness may benefit from suspension, whereas those with very significant submandibular gland ptosis or hypertrophy may be candidates for partial resection.⁶ The idea of aesthetics as an indication for submandibular gland resection, which is a technically challenging operation, is controversial.^2,⁷ The primary criticism for resecting the gland is the risk of nerve injury. Prior to their widespread acceptance, SMAS-rhytidectomy techniques were similarly criticized for their risk to the facial nerve. Through multiple studies documenting the anatomy of the facial nerve and refining the surgical approach to it, SMAS procedures were accepted. Similar studies of the submandibular gland have been undertaken, but controversies remain.⁴ All of the nerves in the area of the gland, with the exception of the autonomic plexus, are found exterior to its capsule.

Contraindications

Contraindications are similar to those for other elective aesthetic procedures such as advanced cardiopulmonary dysfunction, bleeding disorders, connective tissue diseases and wound healing problems.

Preoperative History and Considerations

After understanding the patient’s goals and expectations, the patient’s face is assessed from the front and profile views with the chin and face held in repose and tilting down (reading position, as coined by Connell). The skin, underlying layers of fat, and the submandibular glands are palpated. The patient is asked to tighten the platysma by trying to depress the corners of the mouth and the platysmal bands are observed. If the neck bands become tighter by this type of animation, they are dynamic bands and would respond favorably to surgery or injection of botulinum toxin. If the bands do not become tighter, the skin folds would require skin tightening. The anterior belly of the digastric muscles are palpated to detect hypertrophy.

Operative Approach

Intravenous sedation and injection of lidocaine with 1 : 200 000 epinephrine is sufficient for most patients, even those who undergo partial or complete removal of the submaxillary glands. The standard protocol includes a thorough betadine prep of the neck and oral cavity followed by intraoral administration of local anesthesia to block the area.

Neck exposure is gained through an inconspicuous 3.5 cm submental incision in the shadow posterior to the submental skin crease. This allows access to the platysmal plane. Laterally the neck is approached through a conventional pre- and posterior auricular rhytidectomy incision, if rhytidectomy is part of the goal. This gives good visualization along the inferior border of the mandible, and provides an avenue for directly visualized suction lipectomy of the lateral neck.

SMAS suspension and platysmal plication

Rhytidectomy in conjunction with a neck lift can provide further suspension of the soft tissues of the lateral neck. This is accomplished by the changed vector that results from the transposition of a vertical strip of preauricular SMAS to an anchor point in the retroauricular area. The lift is thereby changed from a vertical one to a more attractive line along the angle of the mandible, with a hammock effect.

• The anterior platysma is best approached by a transverse submental incision.

• The skin is then undermined caudal to the level of the cricoid or beyond.

• To correct the effects of platysmal banding, the muscle is separated in the midline and freed from the underlying subplatysmal fat and anterior muscle bellies of the digastrics.

• The edges of the cut platysma are grasped and brought together in the midline.

• The excess tissue is then resected and the edges reapproximated with an interrupted or running suture (Fig. 10.1). Alternatively, the platysmal borders are overlapped in vest-over-the-pants fashion. Non-absorbable suture is used for the muscle repair.

• Platysmal muscle is released as low in the neck as possible using cautery, if indicated. The muscle can then be allowed to redrape, which provides for a deeper, more attractive cervicomental angle. A release that is too caudal can result in window shading of the platysma over the submandibular glands, or in denervation and lower lip dysfunction.

Fig. 10.1 Platysmal imbrication and redraping of the soft tissues of the neck. This technique tightens the platysma, and resuspends the soft tissues of the submandibular and submental regions. The end result is a more acute cervicomental angle, giving a more youthful appearance to the neck.

Subplatysmal fat resection

• Subplatysmal fat can add considerable convexity to the cervicomental angle. The degree of subplatysmal fat is typically an inherited feature, but may be a reflection of total body fat.

• A subset of patients in whom the midline subplatysmal fat is the only feature of aging in the cervicofacial area can benefit from a subplatysmal fat resection and platysmaplasty alone, requiring only a submental incision.⁸ This has proved particularly beneficial in some young patients. The submental incision gives good exposure medially, but most patients have additional aspects of the aging neck that also require lateral approaches. Although some patients benefit from suction lipectomy alone,⁹ most benefit from platysmal procedures or subplatysmal fat resection.

• Cervicosubmental lipectomy is usually performed after SMAS lift, when it is carried out concomitant with rhytidectomy and SMAS suspension. The fat over the mandibular angle is contoured only after the final muscle position is set to prevent removal of fat from an unintended portion of the jaw line. If this occurs, contour deformities may be apparent on the face.

• Vertical separation of the platysmal decussation in the midline allows visualization of the subplatysmal fat deposit (Fig. 10.2). The fat interposed between the platysma and the anterior bellies of the digastric muscles is conservatively resected with cautery. Open or closed liposuction techniques may be useful adjuncts to neck contouring provided they are used selectively.¹⁰ Most cervical adipose tissue is contoured using long facelift scissors.

• Some authors recommend resection of the anterior digastric muscle bellies if there is residual fullness11,12 – the muscle is isolated and gently detached from the caudal border of the mandible using electrocautery. There is a well-defined plane between the anterior belly of the digastric muscle and the mylohoid muscle leaving some muscle fibers on the bone. The anterior belly of the digastric muscle is pulled caudally and the muscle is partially or completely removed. Meticulous hemostasis is essential.

Fig. 10.2 Subplatysmal fat contouring. The platysma is divided, providing access to deeper fat deposits in the submental region. These may be resected via a midline incision, and along with plication of the platysma, can help restore a more youthful cervicomental contour.

Submandibular gland suspension and resection

• The neck is approached via a submental incision and dissection is carried out beneath the platysma to the area where the submandibular gland has been marked out preoperatively. This allows direct visualization of the submandibular capsule.

• A vertical 1.5 cm capsular incision along the anterior-inferior surface is made parallel to the body of the mandible.

• Careful dissection around the gland frees any inferior or lateral capsular adhesions and allows intracapsular gland mobilization.

• A blunt clamp is inserted until the inferior border of the mandible is encountered, and then is advanced subperiosteally along the lingual aspect of the mandibular body. This is continued until the oral mucosa tents over the instrument tip and a 2–3 mm incision is carefully made with a number 15 scalpel.

• The tip is then delivered into the oral cavity and a 2-0 suture end is brought back out through the neck.

• A second pass is then performed, also from within the glandular capsule, but lateral to the gland. The periosteal tunnel created for this suture is parallel to, but 3 cm anterior to the initial pass. The opposite end of the free suture is grasped and pulled down into the neck.

• After both ends of the suture have been pulled caudally, mild traction on the suture ensures adequate purchase of a sling of periosteum to provide support for the gland. This is the zone of periosteal adhesion.

• The gland is elevated to the level of the posterior belly of the digastric muscle and the inferior border of the mandible with gentle digital pressure (Fig. 10.3).

• The knot is cinched, tied, and the gland’s elevated position secured.

• After a durable suspension is obtained, the incised glandular capsule is imbricated with permanent suture to bolster the suspension sling inferiorly.

• Hemostasis is verified and the intraoral incision closed with a chromic suture.

Fig. 10.3 Submandibular gland procedures. In patients with submandibular glands apparent as lateral ovoid masses present in the neck, glandular suspension or resection may be indicated. Here the approach to the gland and the suspension suture are presented.

The medial to lateral approach to the gland is recommended because it maximally avoids the marginal mandibular nerve, and allows a caudal approach to the gland within the capsule.¹³ Trying to approach the gland via the submental approach is technically difficult due to limited access and the presence of variant blood supply.

A medial to lateral approach to the submandibular gland maximally avoids the marginal mandibular nerve, and allows a caudal approach to the gland within the capsule

Submandibular resection may be a difficult procedure, but can produce dramatic results in selected patients. Codner and Nahai found that submandibular resection was carried out more often in patients undergoing secondary rather than primary rhytidectomies.¹¹ The resection can be done after careful isolation of the gland, ligation of the facial branches entering the gland and Stenon’s duct. Partial removal can be accomplished with electrocautery.

Submaxillary glands should not be removed from patients who have xerostomia or who wear dentures.

Suction drains using TLS vacuum system may minimize the collection of blood or seromas in the neck.

Optimizing outcomes

• Understand the patient’s objectives.

• Obtain an accurate history and physical examination, including preoperative photos on front and profile views.

• Pair the correct procedure to the flaw to be addressed.

• Clearly understand the anatomy, including neurovascular structures to avoid, and techniques to reposition and redrape the tissues of the neck.

• Practice good surgical and anesthetic techniques, including meticulous hemostasis and avoidance of hypertension postoperatively.

• Ensure postoperative follow-up and evaluate one’s results critically and honestly (Fig. 10.4).

Fig. 10.4 59-year-old man with a ptotic submandibular gland before and after submandibular suspension and neck rejuvenation. A,C&E, Preoperative views. B,D&F, Postoperative views.

(Reproduced from Sullivan PK, Freeman MB, Schmidt S. Contouring the aging neck with submandibular gland suspension. Aesthetic Surgery Journal 2006; 26(4):465, with permission from Elsevier)

Complications and Side Effects

Complication rates for neck rejuvenation procedures are similar to those seen after rhytidectomy. Commonly, the side effects of neck lifts are technical. Intraoperative errors in judgment or technique compromise outcomes, but most adverse outcomes can be avoided with due diligence in preoperative planning and careful meticulous surgery.

Complications include:

• hematomas;

• infection;

• seromas;

• irregularities (overcorrection resulting in too sharp a neck angle);

• salivary fistulas;

• dryness of the mouth if the glands are removed from a patient who has pre-existing xerostomia or borderline dryness of the mouth.

Resection of the submandibular gland

The literature supports low complication rates for resection of the submandibular gland.¹⁴^–¹⁷ DePina and Quinta published their experience for eight patients with 12 partially excised submaxillary glands.^1,² Despite occasionally using a direct approach to the gland, rather than the rhytidectomy approach, there were no complications and no salivary fistulas.

Although it has been anecdotally claimed, there is no scientific or statistical evidence of xerostomia following removal of submaxillary glands. However, this potential complication as well as injury to the lingual and hypoglossal nerves should be part of the informed consent.