Head and NeckLive data

CT Soft-Tissue Neck

Contrast-enhanced CT of the soft tissues of the neck evaluates the suprahyoid and infrahyoid fascial spaces, lymph nodes, aerodigestive tract and vasculature. It is the primary modality for deep neck space infection and abscess and a key tool for nodal staging and characterisation of head and neck masses.

Indications

Suspected deep neck space infection, phlegmon or abscess
Nodal staging and detection of nodal metastasis in head and neck malignancy
Characterisation of a palpable or incidentally detected neck mass
Assessment of airway compromise from infection or mass
Evaluation of complications such as jugular thrombophlebitis (Lemierre syndrome) or vascular involvement

Contraindications & Cautions

Severe iodinated contrast allergy without adequate premedication
Significant renal impairment limiting intravenous contrast
MRI preferred for perineural spread, marrow invasion and detailed tumour delineation
Unstable airway requiring immediate management before imaging

Patient Preparation

Screen for iodinated contrast allergy and confirm renal function
Remove dental and neck jewellery to reduce artefact where feasible
Instruct on quiet respiration and suspended swallowing during acquisition
Consider puffed-cheek or phonation manoeuvres for oral cavity and laryngeal lesions

Technique & Parameters

Intravenous contrast (typically 80-100 mL) with imaging at approximately 60-90 seconds (soft-tissue phase)
Coverage from the skull base to the thoracic inlet
Thin collimation (≤1.25 mm) with axial, coronal and sagittal reformats
Angle the gantry or reformat to avoid dental amalgam streak artefact across key regions
Optimise timing to opacify the internal jugular veins and characterise nodal necrosis

Systematic Review

Assign pathology to fascial spaces (parapharyngeal, masticator, submandibular, carotid, retropharyngeal, visceral)
Assess lymph node levels (I-VII) for size, morphology and necrosis
Evaluate the mucosal surfaces of the pharynx and larynx for primary tumour
Inspect the airway for narrowing or displacement
Review vasculature for thrombosis, encasement or pseudoaneurysm and check for osseous erosion

Key Findings & Significance

Rim-enhancing low-attenuation collection with mass effect indicating abscess
Retropharyngeal fluid distinguishing suppurative abscess from oedema/effusion
Pathological nodes: short-axis enlargement, rounded shape, central necrosis or extranodal extension
Infiltrating enhancing primary tumour with deep space and airway involvement
Internal jugular vein thrombophlebitis with an oropharyngeal source (Lemierre syndrome)

Differential Considerations

Abscess versus phlegmon versus reactive lymphadenopathy
Necrotic metastatic node versus suppurative node versus branchial cleft cyst
Squamous cell carcinoma versus lymphoma versus salivary gland tumour
Second branchial cleft cyst versus cystic nodal metastasis (e.g. HPV-related)
Ludwig angina (submandibular/sublingual cellulitis) versus localised submandibular abscess

Pearls & Pitfalls

Extranodal (extracapsular) extension is a key adverse prognostic feature to report in nodal staging
Retropharyngeal abscess can extend into the danger space and mediastinum; assess the full craniocaudal extent
A cystic level II node in an adult should raise suspicion for HPV-associated oropharyngeal carcinoma
Report airway patency explicitly in infective and neoplastic disease to guide urgent management

Structured Report

Localise pathology to the involved fascial space(s) and give dimensions
For infection, distinguish abscess from phlegmon and describe airway impact
Stage nodal disease by level, size, necrosis and extranodal extension
Describe primary tumour extent, deep space invasion and vascular relationships
Note complications (vascular thrombosis, mediastinal extension) and recommend correlation as needed

References

ACR-ASNR-SPR Practice Parameter for the Performance of CT of the Extracranial Head and Neck
Radiographics: Gamss C et al. Imaging of the Deep Neck Spaces and Infections
AJCC Cancer Staging Manual: Head and Neck Nodal Staging
Radiographics: Aulino JM et al. Imaging Evaluation of the Suprahyoid and Infrahyoid Neck

Educational clinical decision support only. Protocols vary by institution and equipment; always confirm with a qualified radiologist and local guidelines before clinical use.

CT Soft-Tissue Neck

📋 Indications

⛔ Contraindications & Cautions

🧑‍⚕️ Patient Preparation

⚙️ Technique & Parameters

🔎 Systematic Review

🩻 Key Findings & Significance

🧠 Differential Considerations

💡 Pearls & Pitfalls

📝 Structured Report

📚 References