Clinical Guidelines on Imaging Acute Head and Neck Infections
Overview
Acute head and neck infections often require imaging to confirm diagnosis, assess extent, and detect complications. Contrast-enhanced CT is the preferred modality in emergencies for complicated infections, while MRI offers additional detail for orbital, skull base, and intracranial involvement.
Background
Acute head and neck infections are common bacterial diseases originating from sinuses, ears, oral cavity, throat, or post-surgical sites, potentially leading to serious complications such as abscesses and intracranial spread. Imaging plays a crucial role in identifying surgically drainable abscesses and complications. Uncomplicated infections generally do not require cross-sectional imaging, whereas complicated cases demand prompt radiologic evaluation to guide management.
Data Highlights
Incidence of acute otitis media: 256/1000 person-years in children vs. 5.3/1000 person-years in adults. Acute invasive fungal sinusitis mortality rate: approximately 50%. Complicated acute otitis media occurs in less than 1% of cases.
Key Findings
Cross-sectional imaging is not indicated for uncomplicated dental, tonsillar, sinonasal, and middle ear infections (high evidence).
Contrast-enhanced CT is recommended in emergency settings for complicated acute sinusitis or middle ear infections to delineate soft tissue infection and abscesses (high evidence).
Contrast-enhanced MRI is valuable for detecting orbital, skull base, and intracranial complications and has a growing role in evaluating soft tissue neck infections (moderate evidence).
Complicated sinusitis often involves orbital spread through the lamina papyracea; intracranial complications, though rare, include cavernous sinus thrombosis and brain abscesses.
Acute invasive fungal sinusitis primarily affects immunocompromised patients and carries a high mortality rate (~50%).
Ultrasonography is useful for initial evaluation of local facial and neck swelling and for image-guided drainage but is limited in assessing deep neck space involvement.
Clinical Implications
Clinicians should reserve imaging for complicated infections presenting with severe symptoms or signs of extension beyond primary sites. Contrast-enhanced CT remains the first-line imaging modality in emergencies due to its availability and ability to assess bone and soft tissue involvement. MRI should be considered when orbital or intracranial complications are suspected. Ultrasonography can be used for superficial collections and guided interventions but is insufficient for deep space evaluation.
Conclusion
Appropriate imaging selection based on clinical presentation is essential for effective diagnosis and management of acute head and neck infections. Contrast-enhanced CT and MRI complement each other in delineating infection extent and complications, guiding timely surgical intervention when necessary.
References
European Society of Head and Neck Radiology -- Clinical Guidelines on Acute Head and Neck Infections
