Ludwig Angina & Airway
- Ludwig angina is a fast-spreading cellulitis of the floor of the mouth — bilateral, in the submandibular and sublingual spaces — and it has nothing to do with the heart.
- The danger isn't pus you can drain; it's the swelling shoving the tongue up and back until the airway closes. The airway is the diagnosis.
- It usually starts in a rotten lower molar, so think teeth, not throat.
- On CT, look for the tongue base pushed posteriorly, edema tracking across the midline, and gas in the soft tissues. Early on there may be no drainable abscess at all.
- The radiologist's job is to flag airway compromise and any spread toward the mediastinum immediately — this is a phone-call finding.
Despite the dramatic name, "angina" here is the old-fashioned meaning — a feeling of strangling or choking — not chest pain. Nobody's having a heart attack. Someone's mouth is quietly trying to seal off their own windpipe, and the clock is running.
What it actually is
Picture the floor of your mouth as a hammock slung under your tongue. Ludwig angina is what happens when an infection sets that whole hammock on fire — a spreading cellulitis (a diffuse soft-tissue infection, not a walled-off pocket of pus) that takes over the submandibular and sublingual spaces on both sides at once. It's woody, firm, and it does not respect tidy boundaries the way a normal abscess does. If you want the map of which space is which, the neck spaces page is the friend to bring along.
The classic starting point is a single bad tooth — usually a lower second or third molar whose roots dangle below the attachment of the mylohyoid muscle, the little muscular shelf that forms that hammock. Infection at those roots drips into the sublingual space and then everywhere, because anatomy is generous when you least want it to be. So when the chart says "toothache three days ago," your ears should perk up.
The "angina" in Ludwig angina is the same root as in angina pectoris — both come from a word for choking or tightness. Here it's literal: the patient feels like they're being strangled from the inside. No coronary arteries involved.
Why it's a don't-miss
Here's the part that kills people. As that hammock swells, it has nowhere to go but up and back, so the tongue gets levered superiorly and posteriorly — picture a speed bump rising in the one hallway air needs to use. The patient drools, can't swallow, can't lie flat, and talks like they have a hot potato in their mouth. The threat is mechanical airway obstruction, and it can arrive faster than anyone is comfortable with.
Ludwig angina is an airway emergency first and an imaging problem second. If a patient is stridorous, drooling, or can't handle their secretions, securing the airway comes before any trip to the scanner. Don't let a sick patient lie flat in a CT bore waiting on pretty pictures — flat positioning can worsen obstruction.
It also doesn't always stay in the neck. The deep neck spaces open downward toward the chest, so a neglected infection can slide into the mediastinum (descending mediastinitis) — a separate, even nastier emergency. Tracking that downward spread is one of the real reasons we image at all.
What you're hunting for on CT
Contrast-enhanced CT of the neck is the workhorse — it shows the extent of disease, finds any drainable collection, and answers the two questions everyone's actually asking: is the airway in trouble, and is this heading for the chest? (If you want the systematic walk-through, see approach to the neck CT.)
The findings that earn their keep:
| Finding | What it means |
|---|---|
| Diffuse edema and fat stranding, bilateral, crossing midline | The cellulitis itself — often present before any abscess forms. |
| Tongue base pushed up and back, narrowed airway | The reason this is an emergency. Describe it explicitly. |
| Rim-enhancing fluid collection | A drainable abscess — surgery can act on this. |
| Gas in the soft tissues | Suggests gas-forming organisms; raises the worry level a notch. |
| Edema tracking inferiorly past the hyoid | Possible descent toward the mediastinum — look at the chest. |
Early Ludwig angina can be a phlegmon — angry, swollen, dangerous tissue with no organized pus to drain yet. Reporting "no drainable collection" as if that's reassuring is the trap. The cellulitis and the airway narrowing are the emergency, with or without a fluid pocket. Say what the airway is doing.
A plain lateral soft-tissue neck film might show prevertebral or floor-of-mouth swelling, but it's a blunt instrument here and shouldn't slow anyone down. CT is the answer when the patient is stable enough to get it.
How to report it like it matters
This is one where the words you choose change what happens to the patient. Lead with the airway: describe the degree of oropharyngeal narrowing and the posterior tongue displacement up front, not buried in paragraph four. Then state whether there's a drainable collection, whether there's soft-tissue gas, and whether edema extends below the hyoid toward the mediastinum.
The single most useful sentence in your report is a clear statement of airway status and inferior extent — then pick up the phone. Findings that threaten the airway or the mediastinum are critical results, full stop.
Ludwig angina sits in the same family as the broader deep neck space infections, and it's worth knowing its loud cousin epiglottitis too — both choke the airway, but from different doorways. If you remember nothing else: the heart is fine, the tooth is guilty, and the airway is the whole story.