MRI Neck — head and neck cancer staging
Primary subsite with high-resolution small field-of-view imaging, plus nodal levels I-V and the retropharyngeal nodes; extend to the skull base where perineural spread is possible.
Typical, not policy
Timings, volumes and delays here are representative values drawn from published guidance. Scanner generation, injector, cardiac output and local preference all move them. Confirm against your department's own protocol before you rely on a number.
When to use it
- Newly diagnosed oral cavity, oropharyngeal, nasopharyngeal or sinonasal cancer requiring local T-staging.
- Assessment of mandibular or maxillary marrow invasion, where MRI outperforms CT.
- Suspected perineural spread along named cranial nerves.
- Carcinoma of unknown primary, to interrogate the tongue base and tonsils.
- Post-treatment surveillance where a structured reporting system is being used and a baseline is required.
Technique
- Small field-of-view high-resolution T2 and T1 through the primary site, with slice thickness kept low enough to resolve the deep margin.
- Whole-neck axial coverage for nodal assessment in a larger field of view.
- Post-contrast fat-suppressed T1 in axial and coronal planes; coronal is the plane that shows skull base and marrow extension best.
- Diffusion adds value for nodal characterisation and for distinguishing post-treatment change from recurrence, though thresholds are not standardised.
Where it goes wrong
- Using one large field of view for both primary and nodes, so the primary is under-resolved.
- Omitting coronal post-contrast imaging and missing skull base or marrow extension.
- Scanning too soon after radiotherapy, when diffuse enhancement and oedema make local staging unreliable — timing is a vetting decision.
- Uncorrected geometric distortion on echo-planar diffusion in the neck, which misregisters the lesion.
Clinical questions that reach this study
Contrast
Gadolinium, intravenous
Macrocyclic gadolinium agent at a typical single dose of about 0.1 mmol/kg; fat-suppressed post-contrast T1 through the primary site and nodal levels.
Acquisition
- Breathing
- Quiet breathing, no swallowing during acquisition.
- Preparation
- Name the subsite. A whole-neck survey answers a nodal question but not a tongue-base or perineural one. Ask about extensive dental metalwork — it may make MRI of the oral cavity uninterpretable and shift the study to CT. Patients who cannot suppress swallowing for several minutes at a time will produce non-diagnostic high-resolution sequences.
Safety checks this protocol carries
Derived from the contrast agent and phases above, not authored here — which is why they cannot drift apart from what the protocol actually does.
- Kidney function and gadolinium-based contrast· radiographer at scan
- Intravenous access adequate for the planned injection· radiographer at scan
- MR safety screening for implants and foreign bodies· radiographer at scan