Deep Neck Space Infections

Deep Neck Space Infections

✨ Classification of Neck Space Infections

Neck space infections can be broadly divided into:

1. Superficial Infections: Involve the skin, subcutaneous tissue, and superficial fascia. Examples include cellulitis, lymphadenitis, subcutaneous abscesses (non-necrotizing) and cervical fasciitis (necrotizing).

2. Deep Infections: Involve the deeper neck tissues surrounded by fascial layers and potential spaces. This is our focus today.

🦠 Etiology (Sources of Infection) of Deep Neck Space Infections

Deep neck space infections often arise from untreated or inadequately treated infections in nearby areas:

• Upper Aerodigestive Tract Infections:

  • Pharyngotonsillitis: Most common cause in children.
  • Dental Infections: Most common cause in adults.

• Dental and Periodontal Disease: Odontogenic infections are a very common source (decay, periodontal disease).

• Sialolithiasis and Sialadenitis

• Medical Comorbidities:

  • Diabetes Mellitus: Most common comorbidity, associated with worse outcomes and higher risk of complications.
  • Age (Elderly patients may present without fever/leukocytosis).
  • Immunocompromise (HIV, chemotherapy, steroid use).

• Congenital Anatomical Abnormalities: Infected Branchial cysts, sinuses, or fistulae.

• Head and Neck Malignancy: Malignant neoplasms can present as or predispose to deep neck infections.

• Miscellaneous: Oral surgical procedures, endoscopic instrumentation, foreign bodies, penetrating trauma, necrotic malignant lymph nodes.

🦠 Pathways of Spread of Deep Neck Space Infections

Infections can spread between interconnected spaces:

• Tonsillitis -> Peritonsillar abscess -> Parapharyngeal space -> Retropharyngeal space and Submandibular space -> Carotid sheath, Visceral space.

• Rhinosinusitis/Pharyngitis -> Retropharyngeal lymph node -> Retropharyngeal space -> Parapharyngeal space, Carotid sheath.

• Dental Infection:

  • Upper Jaw -> Masticator space -> Pterygomaxillary space -> Infratemporal fossa, Parapharyngeal space.
  • Lower Jaw (Second/Third molar) -> Submandibular space -> Parapharyngeal space, Visceral space, Sublingual space.
  • Lower Jaw (First molar) -> Sublingual space.

• Endoscopic Procedure/Trauma -> Parapharyngeal or Retropharyngeal space -> Danger space -> Mediastinum (life-threatening).

🦠 Microbiology of Spread of Deep Neck Space Infections

Deep neck space infections are typically polymicrobial, reflecting the oropharyngeal flora.

• Common Organisms: Streptococcus viridans, Staphylococcus aureus, Peptococcus.
• Also found: Streptococci, Bacteroides, Fusobacterium, Peptostreptococcus.

📍 Specific Deep Neck Space Infections

Let's look at common infections in specific spaces.

1. Buccal Space Infection (Buccinator Space)

• Source: Mandibular/maxillary bicuspids and molars draining laterally through the buccal cortex.

• Presentation:

  • Tender swelling of the cheek, extending to mid-upper lip.
  • Abscess formation bulging into the oral cavity beneath the buccal mucosa.

• Treatment: IV antibiotics, analgesics, hydration, Incision and Drainage (I&D)

• Complications: Venous sinus thrombosis, internal maxillary artery hemorrhage, metastatic abscess, osteomyelitis.

2. Canine Space Infection (Infraorbital Space)

• Source: Maxillary canine or premolar teeth. Also, infection of skin of nose/upper lip.

• Presentation:

  • Swelling lateral to the nose, obliterating the nasolabial fold.
  • Swelling of upper lip, drooping angle of mouth, drooling saliva.
  • Edema of upper and lower eyelids.
  • Severe pain (infraorbital nerve irritation).
  • Tense, erythematous overlying skin.

• Treatment: IV antibiotics, hydration, analgesics. I&D intraorally from corresponding gingivobuccal sulcus.

• Complications: Orbital cellulitis, Cavernous sinus thrombosis, Osteomyelitis, spread to adjacent spaces.

3. Masticator Space Infection

• Source: Most commonly dental infection from second and third molar teeth.

• Presentation:

  • Most common sign: Trismus (due to edema/spasm of pterygoid muscles within the space).
  • Pain, swelling in the affected masticator subdivision area.

• Treatment: IV antibiotics, hydration, analgesics. I&D.

  • Masseteric/Pterygomandibular: Incision lateral to retromolar trigone, blunt dissection.
  • Temporal: Horizontal incision above zygomatic arch.

4. Parotid Space Infection

• Source: Primarily dehydration/salivary stasis (post-surgical, debilitated patients).

• Microbiology: Staphylococcus aureus is common. Streptococci, anaerobes.

• Presentation:

  • Swelling, redness, induration, tenderness in parotid area/angle of mandible (~5-7 days post-op).
  • Usually unilateral, but can be bilateral.
  • Fluctuation difficult to elicit (tight parotid capsule).
  • Pus exuding from Stenson's duct orifice on gland pressure.
  • Toxicity, high fever, dehydration.

• Treatment: Correct dehydration, oral hygiene, promote salivary flow. IV antibiotics, surgical drainage (local or general anesthesia).

• Complications: Facial nerve palsy (iatrogenic during surgery), Parapharyngeal abscess (deep layer rupture), spread to mediastinum, sepsis.

5. Retropharyngeal Abscess

• Source:

  • Children (< 3 yrs): Suppuration of retropharyngeal lymph nodes (secondary to infection in adenoids, nasopharynx, posterior nasal sinuses, nasal cavity).

  • Adult: Penetrating injury to posterior pharyngeal wall/cervical esophagus.

• Presentation:

  • Prominent dysphagia and difficulty breathing.
  • Stridor, croupy cough.
  • Torticollis (neck stiffness, head extended).
  • Bulge in the posterior pharyngeal wall (usually unilateral).

• Diagnosis:

  • Lateral neck radiograph (soft tissue view): Widening of prevertebral shadow (≥7mm at C2 in adults/children, ≥14mm at C6 in children, ≥22mm at C6 in adults; or >50% width of C2 body). Straightening of cervical spine, possible air/fluid level.
  • Contrast-enhanced CT scan: Extent of abscess, communication with other spaces (parapharyngeal).

• Treatment: IV antibiotics, hydration.

Incision and Drainage (I&D): Vertical incision in the most fluctuant area of the posterior pharyngeal wall.

• Complications: Airway obstruction, stridor, hemorrhage, septicemia, metastatic abscess, IJV thrombosis, carotid artery erosion, aspiration pneumonia (spontaneous rupture), spread to other neck spaces.

6. Prevertebral Abscess

• Source: Usually Tubercular (caries of cervical spine). Less commonly, tuberculous retropharyngeal lymph nodes or trauma/fracture of cervical vertebrae.

• Presentation:

  • Neck discomfort, mild dysphagia.
  • Fluctuant swelling in posterior pharyngeal wall (central if from vertebral caries, unilateral if from lymph nodes).
  • Tuberculous lymph nodes in the neck may be present.

• Treatment: IV antibiotics (or Anti-Tubercular Therapy for TB cause). I&D (external approach: vertical incision along anterior/posterior border of SCM depending on abscess level).

7. Danger Space Infection

• Source: Extension of infection from Retropharyngeal abscess (penetrating alar fascia), Prevertebral abscess (penetrating prevertebral fascia), or Parapharyngeal space.

• Clinical Importance: This space's loose tissue allows rapid downward spread to the posterior mediastinum (Mediastinitis). High risk of involvement of vital structures (vena cava, aorta, trachea, esophagus), leading to significant morbidity and mortality.

8. Carotid Space Infection

• Source: Penetrating trauma, direct extension from parapharyngeal space, IV drug injection into IJV.

• Presentation:

  • Fever, chills, persistent tenderness.
  • Induration deep to SCM, torticollis.
  • Edematous pitting on deep pressure (IJV involvement).
  • Repeated small hemorrhages into pharynx (suspect eroded vessel).
  • Warning sign: bleeding from the ear (rare).

• Treatment: Patient stabilization, IV antibiotics, hydration. Drainage of abscess. Anticoagulation (if IJV thrombosis). Ligation of IJV/Carotid artery if erosion/hemorrhage.

9. Parapharyngeal Abscess (Lateral Pharyngeal Space Infection)

• Source:

  • Pharyngeal (tonsils, adenoids, ruptured peritonsillar abscess).
  • Dental (lower last molar).
  • Ear (basal abscess, petrositis).
  • Other spaces (parotid, retropharyngeal, submaxillary).
  • Trauma (penetrating neck injury, local anesthetic injection for tonsillectomy/nerve block).

• Clinical Features: Depend on compartment involved (Pre-styloid vs. Post-styloid).

  • Anterior (Pre-styloid): Prolapse of tonsil/tonsillar fossa, Trismus, external swelling behind angle of jaw, marked odynophagia.

  • Posterior (Post-styloid): Bulge of pharynx behind posterior pillar, Cranial nerve palsies (IX, X, XI, XII), sympathetic chain dysfunction (Horner's syndrome), parotid region swelling, minimal trismus/tonsillar prolapse.

  • Common Features: Fever, odynophagia, sore throat, torticollis, signs of toxemia.

• Diagnosis: Contrast-enhanced CT scan (extent). MR Angiography (if IJV thrombosis, ICA aneurysm suspected).

• Treatment: Systemic IV antibiotics, Hydration, Surgical drainage under general anesthesia. Pre-operative tracheostomy may be mandatory if marked trismus/airway compromise.

  • Incision: Horizontal incision 2-3 cm below angle of mandible. Transoral drainage should NOT be done (risk to great vessels).

• Complications: Laryngeal edema/airway obstruction, IJV thrombophlebitis/septicemia, spread to retropharyngeal/carotid spaces and Mediastinum, Mycotic aneurysm/Carotid blowout, pharyngeal perforation (cervical necrotizing fasciitis).

10. Peritonsillar Abscess (Quinsy)

• Source: Usually follows acute tonsillitis. Can also arise de novo, from foreign body, periodontitis, infectious mononucleosis, tonsillar remnants.

• Bacteriology: Streptococcus pyogenes, Staphylococcus aureus, anaerobes (often mixed).

• Presentation:

  • Common in adults, rarely children. Usually unilateral.
  • General: Fever, chills, rigor, malaise, body ache (septicemia signs).
  • Local: Severe, unilateral throat pain, marked Odynophagia (can't swallow saliva, drooling), dehydration, muffled/thick speech ("Hot Potato Voice"), foul breath, ipsilateral otalgia (referred via CN IX), Trismus (pterygoid spasm).

• Treatment:

  • Hospitalization. IV fluids (dehydration). IV antibiotics (aerobic + anaerobic). Analgesics (Paracetamol, avoid Aspirin - bleeding risk). Oral hygiene (mouthwashes).

  • If frank abscess: Incision and Drainage (I&D): At point of maximum bulge OR junction of anterior pillar and line through base of uvula (guarded knife stab incision, suction ready). Aspiration can be done first.

  • Tonsillectomy: Interval tonsillectomy (4-6 weeks post-Quinsy). Abscess/Hot tonsillectomy (at time of I&D - higher risk of bleeding, rupture under anesthesia).

• Complications (Rare now): Parapharyngeal abscess, laryngeal edema/airway obstruction, septicemia, aspiration pneumonia/lung abscess, IJV thrombosis, carotid artery hemorrhage, mediastinitis.

11. Submental Space Infection

• Source: Infections from anterior mandibular teeth burrowing below the mylohyoid muscle (rarely isolated).

• Presentation: Erythema, induration, tenderness over skin and soft tissue in the submental region.

• Treatment: IV fluids, antibiotics, analgesics. Submental I&D.

12. Submandibular Space Infection

• Source: Infections from second/third mandibular molars. Mandibular fractures, foreign bodies, malignancies.

• Presentation:

  • Swelling beginning at inferior lateral border of mandible, extending medially to digastric area.
  • Pain, fever, malaise, toxic look.
  • Induration, erythema in submandibular area extending to hyoid.

• Treatment: IV fluids, antibiotics, analgesics. Treat underlying cause. External drainage.

• Complications: Airway obstruction, aspiration pneumonia/lung abscess, progression to Ludwig's Angina, osteomyelitis, tongue necrosis, spread to sublingual, parapharyngeal, retropharyngeal spaces.

13. Sublingual Space Infection

• Source: Dental caries involving premolar/first molar. Mandibular fracture/malignancy.

• Presentation:

  • Intraoral lingual swelling in floor of mouth (minimal extraoral swelling).
  • Edema/induration of floor of mouth.
  • Tongue displacement medially/superiorly.
  • Dysphagia, odynophagia.

• Treatment: IV fluids, antibiotics, analgesics. Intraoral I&D (if localized).

14. Ludwig's Angina

• Source: Predominantly dental infections. Other causes: submandibular sialadenitis, oral mucosa injuries, mandibular fractures, floor of mouth trauma, dental extraction, mandibular malignancy, osteoradionecrosis.

• Presentation:

  • Marked odynophagia, varying trismus.
  • Swollen floor of mouth structures.
  • Tongue pushed up and back (threatening airway).
  • Swollen, tender submandibular region with a characteristic "woody hard" feel.
  • Laryngeal edema may appear.
  • Halitosis, drooling, fever, malaise.

• Treatment:

  • Airway management is paramount (assess laryngeal edema, potential for obstruction).
  • IV fluids, systemic antibiotics (broad spectrum for mixed infection).
  • I&D: If sublingual only -> intraoral. If submaxillary involved -> external incision (transverse from angle to angle of mandible, vertical midline opening, blunt hemostat).

• Complications: Spread to parapharyngeal/retropharyngeal spaces and Mediastinum, airway obstruction (laryngeal edema, tongue displacement), septicemia, aspiration pneumonia/lung abscess, IJV thrombosis, carotid vessel erosion.

15. Anterior Visceral Space (Pretracheal Space) Infection

• Source: Infection from tonsil, trauma to hypopharynx/anterior esophagus/larynx, thyroid infections.

• Presentation:

  • Fever, malaise. Hoarseness, muffled voice (laryngeal edema).
  • Dyspnea, odynophagia.
  • Tenderness over larynx.
  • Unilateral swelling/redness in hypopharynx/piriform sinuses with subsequent supraglottic/glottic involvement.

• Treatment: IV fluids, antibiotics, analgesics. I&D: Transverse incision along anterior border of SCM over abscess area.

• Complications: Laryngeal edema/airway obstruction (-> tracheostomy), Mediastinitis.

This concludes our discussion on deep neck space infections. Understanding the source, spread, clinical presentation, and prompt management of these infections is critical for patient outcomes.