Patient guide · Vascular imaging
Magnetic resonance angiogram (MRA), radiation-free vascular imaging — intracranial, carotid, aortic, renal and peripheral.
A magnetic resonance angiogram (MRA) images blood vessels without ionising radiation. Time-of-flight, phase-contrast and contrast-enhanced MRA are used for intracranial aneurysms, carotid disease, aortic aneurysm surveillance, renal artery stenosis and peripheral arterial disease.
Reviewed by Pulse Atlas Editorial Board, · 5-minute read · Next review 2027-07-30
Key facts about MRA
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Definition
MR imaging of arterial and venous vessels — head, neck, chest, abdomen or limbs.
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No ionising radiation
MRA uses magnetic fields and radio waves — safe for repeat surveillance.
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Time-of-flight for brain
Non-contrast TOF-MRA is the go-to sequence for intracranial aneurysm screening.
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Contrast-enhanced for aorta
Gadolinium CE-MRA gives the sharpest picture of the aorta and peripheral run-off.
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Non-contrast options
Phase-contrast and quiescent-interval sequences when renal function limits gadolinium.
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Consultant radiologist reports
Every MRA is reviewed and reported by a consultant neuro- or vascular radiologist.
How an MRA is done
From referral to report — what happens, in order.
MRA is straightforward once the safety questionnaire is complete. Most studies take under an hour, from arrival to walking out.
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Before
Consultation and referral
Symptoms, prior imaging and referral reviewed to confirm MRA is the correct study and sequence.
- 02
Before
Metal safety check
Full MRI safety questionnaire — implants, pacemakers, aneurysm clips, cochlear devices, retained foreign bodies.
- 03
On the day
IV cannula for contrast
A small cannula is sited for gadolinium contrast-enhanced sequences where required.
- 04
On the day
Position in scanner
You lie on the scanner table with the relevant coil placed over the region being imaged.
- 05
On the day
Sequence acquisition
10–30 minutes of imaging: TOF, phase-contrast, or contrast-enhanced sequences as clinically indicated.
- 06
After
Post-processing 3D reconstruction
Raw data is reconstructed into maximum-intensity projections and 3D vascular maps for review.
- 07
After
Radiologist report
A written report from the consultant radiologist, with onward vascular, neurovascular or surgical pathway if needed.
What it shows
When an MRA is the right test.
MRA answers targeted vascular questions — from a suspected berry aneurysm to a run-off study before peripheral revascularisation.
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Intracranial aneurysms
TOF-MRA screening and surveillance of berry aneurysms and vascular malformations.
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Carotid stenosis
Contrast-enhanced MRA of the carotid bifurcation when ultrasound is inconclusive.
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Aortic aneurysm / dissection
Full thoraco-abdominal aortic imaging for aneurysm sizing and dissection follow-up.
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Renal artery stenosis
Non-contrast or CE-MRA in resistant hypertension and suspected fibromuscular dysplasia.
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Peripheral arterial disease
Run-off MRA from aorta to ankle in claudication and critical limb ischaemia work-up.
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Vertebral artery dissection
Fat-saturated sequences to visualise intramural haematoma and luminal narrowing.
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Coronary variants
Anomalous coronary origins and course — problem-solving when CT is contraindicated.
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Red flag: acute stroke / dissection features — emergency neuroradiology pathway
Sudden focal neurology, thunderclap headache or new pulse deficit — 999, not a private slot.
Treatment options
What happens after the MRA report.
The MRA is a decision-making tool. What follows depends on the finding — from reassurance to same-week vascular intervention.
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Reassurance for normal MRA
A clean MRA with a clear normal report — no further vascular imaging required.
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Endovascular coiling / clipping
Neurosurgical or interventional neuroradiology referral for treatable aneurysms.
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Carotid endarterectomy / stent
Symptomatic 50–99% carotid stenosis routed to the vascular surgery team.
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Aortic surveillance or repair
Serial MRA, EVAR or open repair depending on aneurysm size and morphology.
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Renal artery stenting
Interventional radiology referral for haemodynamically significant renal artery disease.
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Peripheral revascularisation
Angioplasty, stenting or bypass planning based on MRA run-off anatomy.
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Anticoagulation for dissection
Medical management pathway for carotid or vertebral artery dissection.
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Structured vascular follow-up
Timed repeat MRA for aneurysm growth, endoleak surveillance or post-intervention review.
Red flags
When MRA becomes urgent.
Some findings — or the clinical picture around them — change the pathway. These are the ones where speed matters.
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Ruptured aneurysm
Thunderclap headache or sudden collapse — 999. Not a private appointment.
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Acute aortic dissection
Tearing chest or back pain with pulse asymmetry — emergency CT aorta, not elective MRA.
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Critical limb ischaemia
Rest pain, tissue loss or gangrene — same-day vascular surgery referral.
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Cerebral aneurysm > 7 mm
Increased rupture risk — neurovascular MDT review for treatment planning.
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Fibromuscular dysplasia
Beaded appearance in a young patient with hypertension — full vascular survey.
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Post-dissection follow-up
Structured MRA surveillance to detect progression, aneurysmal change or re-dissection.
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Post-EVAR endoleak
Contrast MRA to characterise type and source of endoleak after aortic repair.
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Post-carotid intervention restenosis
MRA when duplex ultrasound raises concern about in-stent or endarterectomy site disease.
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Uncontrolled renovascular hypertension
Renal MRA to identify a treatable stenosis in resistant hypertension.
Frequently asked
Everything we get asked about MRA.
When to choose MRA over CT, contrast questions, implant safety, scan duration and when to escalate to emergency care.
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What is a magnetic resonance angiogram (MRA)?
MRA is an MRI technique that images blood vessels — arteries and veins — without ionising radiation. Three main approaches are used: time-of-flight (TOF), phase-contrast, and contrast-enhanced (gadolinium) MRA. The right sequence depends on the vessel territory being imaged.
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When is MRA used instead of CT angiography?
MRA is preferred when avoiding ionising radiation matters — younger patients, pregnancy, and long-term surveillance of aneurysms or dissection. CT angiography remains faster and often first-line in the acute setting.
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Do I need contrast (gadolinium) for MRA?
Not always. Time-of-flight MRA is contrast-free and standard for intracranial aneurysm screening. Aortic, peripheral and renal MRA usually benefit from contrast. Non-contrast alternatives exist when kidney function is reduced.
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How long does an MRA scan take?
A focused MRA takes 10–30 minutes in the scanner, plus 10–15 minutes for checks, cannulation and positioning. Combined MRI and MRA studies take longer.
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Is MRA safe with metal implants?
Most modern implants are MRI-conditional, but every implant must be checked before scanning. Older aneurysm clips, some cochlear implants and certain pacemakers can be contraindications — the safety questionnaire is essential.
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What are the red flags that mean I need emergency care, not an elective MRA?
Thunderclap headache, sudden one-sided weakness, slurred speech, tearing chest or back pain, or acute limb ischaemia are 999 calls, not private appointments. Emergency imaging and treatment pathways are far faster than any elective slot.
Sources
What this guide is based on.
Guidelines and standards from radiology and vascular ultrasound bodies in the UK, Europe and the US.
Related tests
Looking for a different test?
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Carotid ultrasound imaging
First-line neck-vessel Doppler for TIA and stroke work-up.
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AAA screening
Ultrasound surveillance of the abdominal aorta.
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MRI brain
Structural brain MRI — often paired with intracranial MRA.
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All tests
Browse every test and procedure we arrange.
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In practice, in London
Where magnetic resonance angiogram mra sits in a private London pathway
With magnetic resonance angiogram mra, the London question is usually about report turnaround and the radiologist reading it — not whether the scan is available. The wait for magnetic resonance angiogram mra on the NHS depends heavily on where you live and how urgently the referral is graded. Central and West London private clinics can normally book within a week, with imaging or a procedure slot to follow shortly after. It’s worth being honest about the reason for going private: usually it’s time, not a fundamentally different test.
A private magnetic resonance angiogram mra pathway in London usually looks like this: an initial consultation, any diagnostics booked at a nearby facility (most within Zone 1 or 2), and a written report sent to you and your GP within a few days. The consultants we work with hold NHS posts alongside their private lists, which keeps the standards consistent across both settings. For magnetic resonance angiogram mra specifically, the difference between a routine report and a sub-speciality read is where private care earns its keep.
Where a good concierge earns its keep is in the matching. There are dozens of consultants in London who see magnetic resonance angiogram mra — but not all of them are the right fit for every case. We narrow it down based on subspecialty, insurer coverage, the specific question being asked, and whether continuity into treatment matters. The right first appointment saves you from repeating yourself later.