About a prostate MRI scan
The prostate is a small gland below the bladder that surrounds the tube that carries urine (the urethra). A prostate MRI uses a strong magnetic field and radio waves, not X-rays, to show the gland and the area around it in detail.
The scan is most often used after a raised PSA blood test. A high PSA does not mean you have cancer – it can also be raised by an enlarged prostate, a urine infection, recent ejaculation or exercise. In the NHS, men referred with possible prostate cancer now usually have an MRI before any biopsy. The scan shows whether there is an area that looks suspicious, which can help you and your doctor decide whether a biopsy is needed and, if so, guide it to the right place. A normal scan may mean a biopsy can be avoided. MRI is also used to monitor men on active surveillance for a low-risk prostate cancer.
If your specialist has asked specifically for a multiparametric MRI with contrast, book our multiparametric prostate MRI instead; if you are unsure which scan you need, contact us before booking. You can read more in our article on prostate cancer.
What happens during the scan
You lie on your back on the scanner bed with a coil placed over your lower abdomen; no probe is placed in the back passage. The scanner is loud, so you will wear ear plugs or headphones, and the radiographer can talk to you throughout. You need to keep very still. Some centres give an injection of Buscopan (hyoscine butylbromide), a medicine that briefly slows the movement of the bowel so the pictures are sharper.
An injection of contrast dye may be used at some centres; where contrast is needed, it is charged separately.
What the scan can show
A prostate MRI can help to look at:
- possible prostate cancer after a raised PSA test
- whether a biopsy is needed, and where to take it
- changes over time in men on active surveillance
- whether a cancer has spread beyond the prostate
- an enlarged prostate and inflammation (prostatitis)
An enlarged prostate is common in men over 50, is not caused by prostate cancer and does not increase your risk of it; it is usually assessed with other tests rather than MRI.
Preparing for your scan
Follow the instructions the centre gives you when you book. Some centres ask you to empty your bowels before the scan or give you a small enema, and some ask you to avoid ejaculating for 2–3 days beforehand, as this can help show the seminal vesicles more clearly. You can usually eat and drink normally.
If Buscopan may be used, tell the centre if you have glaucoma, heart problems, myasthenia gravis or difficulty passing urine. Buscopan can cause blurred vision for a short time, so do not drive until your eyesight is back to normal. Tell the centre if you have had a hip replacement, as metal hips can affect the pictures of the prostate. Upload your recent PSA results and any previous biopsy or scan reports when you book.
You can usually eat, drink and take your normal medicines unless the scanning centre tells you otherwise. Wear loose, comfortable clothing without metal zips or buttons, and leave jewellery at home. You will be asked to remove metal items such as hair clips, hearing aids, coins and keys, and you may be asked to change into a gown.
Before the scan you will complete a safety questionnaire. Tell the team if you have a pacemaker, any metal implant, surgical clips or other device, if you have kidney problems or allergies, or if you are, or might be, pregnant or breastfeeding. If you feel anxious in enclosed spaces, let us know when you book. Some centres can offer a relaxant, and if you take one you will need someone to take you home and must not drive for 24 hours.
Frequently asked questions
My PSA is raised. Does that mean I have cancer?
No. PSA can be raised by an enlarged prostate, an infection, recent ejaculation, exercise or cycling. An MRI helps show whether there is an area of the prostate that needs further tests.
What is the difference between this and a multiparametric MRI?
A multiparametric (mpMRI) scan combines several types of pictures, including a contrast injection, and is the scan usually requested by urologists before a biopsy. If your referral asks for an mpMRI, please book the multiparametric prostate MRI page.
What does my PI-RADS or Likert score mean?
The radiologist scores the scan from 1 to 5 for how likely it is that there is a cancer needing treatment: 1–2 unlikely, 3 uncertain, 4–5 likely. With a score of 1 or 2 you may be able to avoid a biopsy and have PSA checks instead; with 3 or more a biopsy is usually offered. Your doctor will explain what your score means for you.
Do I need a referral?
You can tell us if you have a referral from your GP, physiotherapist or consultant and upload it when you book. If you do not have one, select “no referral” when you book and the scanning centre will confirm the next steps with you.
Sources
- NHS – PSA test
- NHS – Tests and next steps for prostate cancer
- NHS – Enlarged prostate
- Prostate Cancer UK – MRI scan
- NHS – MRI scan
The information on this page has been gathered from various sources and is provided for general information only. It is not medical advice. TOP MRI is not liable for the accuracy or completeness of this information. Please speak to your doctor or the scanning centre about your own situation.