MRI Breast — abbreviated protocol
Both breasts and axillae, prone.
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
- Supplemental screening in women with dense breasts at intermediate risk, where scanner capacity would not support full protocols.
- High-volume screening programmes where sensitivity is preserved but table time and cost must fall.
- A pre-agreed screening pathway with a defined recall route to a full diagnostic protocol.
Technique
- A single pre-contrast fat-suppressed T1 and one or two early post-contrast acquisitions, read primarily on subtraction and maximum intensity projection images.
- A T2 or fluid-sensitive sequence is retained in most published schemes; ultrafast first-pass sampling is added in some.
- Any suspicious finding triggers a full diagnostic protocol rather than being characterised on the abbreviated data.
- There is no single agreed abbreviated protocol; published versions differ in whether T2 and diffusion are retained.
Where it goes wrong
- Using an abbreviated protocol for a diagnostic question such as extent of disease, where kinetics and full sequence coverage are needed.
- No defined pathway for converting to a full protocol when an abnormality is found, so the patient is recalled for a second visit and second contrast dose.
- Assuming kinetic assessment is possible from one or two time points.
Clinical questions that reach this study
Contrast
Macrocyclic gadolinium agent at a typical single dose of about 0.1 mmol/kg with saline flush; one pre-contrast and a small number of early post-contrast acquisitions.
Acquisition
- Breathing
- Free breathing.
- Reconstruction
- First post-contrast subtraction and maximum intensity projection are the primary reading set.
- Preparation
- In premenopausal women, background parenchymal enhancement is lowest in the second week of the cycle; scheduling around day 7-14 is conventional where the question allows waiting. Give the date of any biopsy, surgery or radiotherapy — post-treatment enhancement is a scheduling problem, not just a reporting one. An implant-integrity question needs no gadolinium at all; separate it from an oncological question on the request.
Phases
Each phase is authored once and shared across every protocol that uses it, so the physiology below is the same wherever you meet it.
- Non-contrast (unenhanced)No injection. Acquired before any contrast is given.
Shows intrinsic tissue attenuation, and nothing else. The transferable principle is that contrast is anti-signal for anything that is already dense: calcification, acute haemorrhage, urinary and biliary calculi, iodine-containing or haemorrhagic fluid, and intrinsic fat all lose conspicuity, or become uninterpretable, once surrounding tissue enhances. It is also the only baseline against which enhancement can be measured, so any protocol that quantifies enhancement or washout (a lesion "enhances by X HU", adrenal absolute washout, renal mass characterisation) is arithmetically impossible without it. Conversely, an unenhanced series adds dose and no information whenever the question is purely about vascularity or perfusion.
- Dynamic contrast-enhanced series (multiphase gadolinium)A late arterial acquisition timed to about 15–20 s after contrast reaches the target artery (fluoroscopically triggered or test-bolus timed), a portal venous/early venous acquisition roughly 15–30 s later, and a delayed or transitional acquisition at about 2–3 min. Confirm locally.
The same volume is imaged repeatedly across the passage of a gadolinium bolus, so enhancement is read as a curve rather than as a single value. The transferable principle is that MR sees T1 shortening rather than photon attenuation, which removes the dose penalty for repeating an acquisition and therefore makes the TEMPORAL PATTERN the primary datum: rapid arterial uptake followed by relative fall-off, progressive centripetal fill-in, and persistent late enhancement are three different diagnoses that can share an identical single-timepoint appearance. Because everything downstream depends on hitting the arterial peak within a few seconds, the phase is unusually sensitive to circulation time and to breath-hold failure, and a mistimed arterial acquisition cannot be recovered by post-processing.
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.
- Prior contrast reaction and elective premedication· nurse pre scan
- 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
- Gadolinium in known or possible pregnancy· radiographer at scan