Submandibular Gland Surgery

Submandibular Gland Surgery

It is a surgical procedure that involves surgical removal of the submandibular salivary gland.

Indications

1. Recurrent sialadenitis
2. Sialolithiasis
3. Benign tumours
4. Malignant tumours
5. As part of a selective, modified, radical neck dissection to remove lymph nodes in level I of the neck

Contraindications

1. Known high grade malignancy
2. Bleeding disorder
3. Acute infection
4. Stones confined to the distal portion of Wharton’s duct

Steps of submandibular gland surgery

1. The patient lies supine with the face turned away from the operative side.
2. A horizontal incision is made at least 2 cm below the inferior border of the mandible parallel to a natural skin crease. The length of the incision should be 3-4 cm.
   
   
3. Protection of the Marginal mandibular branch of the facial nerve. The marginal mandibular branch of the facial nerve enters the neck 1cm in front of the angle of the mandible, loops over the facial artery and vein 2cm below the lower border of the body of the mandible before sweeping superiorly to the angle of the mouth.
   Generally, the submandibular gland is removed without the identification of the marginal mandibular nerve to avoid its injury. For this, a superior subplatysmal flap is not raised as the marginal mandibular branch of the facial nerve runs in the same tissue plane. Elevation of the subplatysmal flap superiorly may cause inadvertent injury to the nerve and cause paresis in the postoperative period.
   Therefore, dissection is initially directed to the inferior surface of the gland and proceeds cautiously along the capsule from inferior to superior until the facial vessels are ligated and reflected superiorly (subcapsular flap is elevated). The marginal mandibular nerve lies lateral to the facial vessels and can then be lifted out of the operative field by traction.
4. During inferior dissection, keep dissection over the digastric muscle to prevent injury of the hypoglossal nerve which runs deep to the digastric muscle.
5. Identification of the hypoglossal nerve. The posterior border of mylohyoid muscle is retracted anteriorly and the submandibular gland is pulled superiorly to expose the course of the hypoglossal nerve. The nerve runs on the surface of the hyoglossus muscle.
   
   
6. Identification of the lingual nerve and submandibular ganglion. The posterior border of mylohyoid muscle is retracted anteriorly and the submandibular gland is pulled inferiorly which draws the lingual nerve inferiorly into the field of dissection. The submandibular ganglion is surgically identified as the attachment point of the gland to the lingual nerve.
   
   
7. Identification of submandibular duct for ligation. The posterior border of mylohyoid muscle is retracted anteriorly and the submandibular gland is pulled posteriorly to identify the submandibular duct on tension.
8. The lingual nerve appears as a ribbon-like band loosely attached to the body of the gland by a few fibres – the parasympathetic secretomotor supply. These fibres are dissected carefully which releases the lingual nerve from the gland. The submandibular gland duct is covered by the sublingual gland and should be separated before tying it. It is important to palpate the submandibular gland duct to ensure there are no stones in the duct. The duct is then divided and tied off.
9. Ligate the proximal facial artery as it emerges from deep to the posterior belly of the digastric and remove the gland.
10. A small vacuum drain is inserted and brought out through the skin posteriorly. The wound is closed in two layers.

Complications

1. Marginal mandibular nerve injury
2. Lingual nerve injury
3. Hypoglossal nerve injury
4. Retained stone in distal portion of Wharton’s duct.
5. Bleeding and hematoma
6. Infections rare; antibiotics only used preoperatively if history of sialadenitis

——– End of the chapter ——–

Learning resources.

• Scott-Brown, Textbook of Otorhinolaryngology-Head and Neck Surgery.
• Susan Standring, Gray’s Anatomy.
• Stell and Maran’s, Textbook of Head and Neck Surgery and Oncology
• Frank H. Netter, Atlas of Human Anatomy.
• B.D. Chaurasiya, Human Anatomy.
• P L Dhingra, Textbook of Diseases of Ear, Nose and Throat.
  
  
  Author:

Dr. Rahul Bagla
MBBS (MAMC, Delhi) MS ENT (UCMS, Delhi)
Fellow Rhinoplasty & Facial Plastic Surgery.
Renowned Teaching Faculty
Mail: msrahulbagla@gmail.com
India