Overall CT features are suggestive of left neck necrotizing fasciitis with left internal jugular vein thrombophlebitis and significant airway displacement. The patient has newly diagnosed diabetes mellitus, which is commonly associated with necrotizing fasciits.

Proceed with urgent surgery and tracheostomy. Intraoperative findings: Multi-loculated abscesses involving multiple left deep neck compartments. 100cc pus evacuated. The underlying fascia and muscles are unhealthy, macerated, and sloughy. The underlying tissue was debrided and curetted. 

Necrotizing fasciitis is rare in the head and neck region and commonly occurs in the abdomen, groin, and extremities. Whenever necrotizing fasciitis is suspected, immediate CT examination is mandatory for assessing the extension and guiding the surgical approach.

To differentiate between head and neck necrotizing fasciitis and the more common neck abscess, the following points would be helpful:

• Necrotizing fasciitis usually shows an area of fluid accumulation without significant rim enhancement at the periphery post-contrast administration ¹.
• necrotizing fasciitis usually has multiple air locules/gas in different fascial planes of deep neck spaces, though sometimes it can present without air locules. The abscess sometimes has an air-fluid level but without the presence of multiple tiny air locules in different fascial planes. Viewing the CT neck in the lung window is very helpful for assessing air locules.
• Necrotizing fasciitis has a bizarre-shaped hypodense collection. The abscess has a relatively well-defined or multiloculated collection.
• Necrotizing fasciitis involves multiple neck compartments, where abscesses are usually confined to one compartment.