28. Congenital, traumatic and inflammatory diseases of the neck

1. Congenital diseases

A. Thyroglossal duct cyst

• Remnant of the thyroglossal duct (descent of the thyroid from the foramen caecum)
• Most common congenital neck mass in children
• Midline, at or below the hyoid bone
• Moves up on swallowing and on tongue protrusion
• May become infected → abscess, fistula
• Ultrasound → confirms cyst and a normal thyroid gland
• Treatment → Sistrunk operation: excision of the cyst, the tract and the central part of the hyoid bone
• Simple excision → recurrence up to 50%
• Ectopic (lingual) thyroid → may be the only thyroid tissue

B. Branchial (cleft) cyst

• Remnant of the second branchial cleft in 95%
• Young adults, 20–30 years
• Anterior border of sternocleidomastoid, junction of upper and middle thirds
• Smooth, fluctuant, transilluminates poorly; contains cholesterol crystals
• Branchial fistula → opening at the lower third of the anterior border of sternocleidomastoid; tract passes between internal and external carotid arteries to the tonsillar fossa
• Differential diagnosis in an adult → cystic metastasis of HPV-related oropharyngeal or papillary thyroid cancer
• Treatment → complete surgical excision, after infection has settled

C. Lymphatic malformation (cystic hygroma)

• Malformation of lymphatic channels
• Infants, posterior triangle of the neck
• Soft, compressible, brilliantly transilluminant
• Complications → airway compression, infection, haemorrhage
• Treatment → sclerotherapy (OK-432, doxycycline, bleomycin), surgical excision, sirolimus

D. Other congenital lesions

• Dermoid cyst → midline, does not move with tongue protrusion
• Congenital muscular torticollis → fibrosis of sternocleidomastoid; head tilted to the affected side, chin to the other side
• Cervical rib → thoracic outlet syndrome
• Haemangioma
• Laryngocele

2. Traumatic diseases

Mechanism

• Penetrating → stab, gunshot
• Blunt → strangulation, hanging, road traffic accidents, seat belt

Penetrating injuries breach platysma → zones of the neck

1. Zone I → clavicles and sternal notch to cricoid cartilage; great vessels, trachea, oesophagus, thoracic duct
2. Zone II → cricoid to angle of the mandible; carotid and vertebral arteries, jugular veins, larynx, pharynx
3. Zone III → angle of the mandible to skull base; distal carotid, pharynx

Hard signs (immediate surgery)

• Airway compromise
• Expanding or pulsatile haematoma
• Active bleeding
• Shock
• Bruit or thrill
• Air bubbling from the wound
• Massive haemoptysis or haematemesis

Soft signs (CT angiography first)

• Dysphagia, dysphonia
• Subcutaneous emphysema
• Non-expanding haematoma

Management

• ATLS → airway first; intubate early before swelling
• Do not probe a neck wound; do not remove an impaled object outside theatre
• Hard signs → neck exploration
• Stable with soft signs → CT angiography, endoscopy, contrast swallow
• Blunt injury → laryngotracheal fracture, carotid dissection (stroke)

3. Inflammatory diseases

A. Acute lymphadenitis

• Secondary to infection of the tonsils, teeth, scalp, skin
• Tender, enlarged nodes; may suppurate → abscess
• Treatment → treat the source, antibiotics; drain the abscess

B. Tuberculous lymphadenitis (scrofula)

• Most common extrapulmonary tuberculosis
• Matted, painless nodes in the posterior triangle or jugular chain
• Cold abscess → collar-stud abscess, discharging sinus
• Diagnosis → FNA, culture, polymerase chain reaction (PCR)
• Treatment → anti-tuberculous drugs for 6 months; aspirate cold abscess through healthy skin; excise residual nodes

C. Deep neck space infections

• Source → teeth, tonsils, pharynx, intravenous drug use
• Peritonsillar abscess (quinsy) → trismus, uvula pushed to the other side, hot potato voice; needle aspiration or incision
• Parapharyngeal abscess → swelling behind the angle of the mandible, trismus; risk to carotid sheath
• Retropharyngeal abscess → children; neck stiffness, dysphagia, stridor; widened prevertebral space on lateral X-ray; spreads to the mediastinum (danger space)
• Ludwig's angina → floor of the mouth
• Diagnosis → contrast CT of the neck and chest
• Treatment → airway, intravenous antibiotics, surgical drainage
• Complications → mediastinitis, internal jugular vein thrombosis (Lemierre's syndrome, Fusobacterium necrophorum), carotid artery erosion, sepsis

D. Other

• Sialadenitis, thyroiditis
• Actinomycosis → woody hard swelling, multiple sinuses, sulphur granules
• Cat-scratch disease, toxoplasmosis, HIV