Bladder Ultrasound: Information and Get a Scan

A bladder ultrasound (sometimes called a bladder sonogram) is a common type of medical scan that doctors use to diagnose a range of conditions that can affect the bladder and urinary tract.

Key Takeaways:

An ultrasound scan uses high-frequency sound waves transmitted through a probe called a transducer to create images of the inside of the body in real time, and is a painless, non-invasive procedure
During an ultrasound of the bladder, a medical professional called a sonographer moves a transducer across the skin that covers the lower abdomen and pelvic region
The results from a bladder ultrasound help doctors understand what might be causing symptoms that affect the urinary tract, such as an inability to hold urine, difficulty or pain when urinating or blood in the urine
This type of bladder scan is used to diagnose or rule out several medical conditions, including urinary tract infections (UTIs), blockages in the urinary tract and bladder cancer

What is a Bladder Ultrasound?

The bladder is a muscular, sac-like organ that the body uses to hold urine before it’s passed from the body. It forms part of the urinary tract, which comprises:

A left and a right kidney, which both produce urine
A pair of tubes, one from each kidney, to the bladder, called the ureters
The bladder, which expands as it slowly fills with urine
A tube called the urethra that takes urine from the bladder to be eliminated into the toilet when we urinate

A bladder ultrasound is a type of bladder scan that looks at the size and shape of the bladder without the need for painful or invasive procedures. It also looks at its structure and function, including how it behaves when it’s holding urine and if it’s able to fully empty during urination.

Ultrasound scans are carried out as an outpatient procedure, and you’ll need to drink water beforehand so that you have a full bladder.

During a bladder ultrasound, a medical professional called a sonographer places a small medical device called a transducer, or ultrasound probe, over your lower abdomen in your pelvic area. Computers attached to the transducer create black and white images of the size and shape of the bladder that can then be checked for abnormalities by a specialist doctor.

Why You Might Need a Bladder Ultrasound

If you regularly experience any of the following symptoms, speak to your GP, who may refer you for a bladder scan:

Difficulty fully emptying your bladder
Difficulty urinating at all
Difficulty holding urine in your bladder
Leaking urine
Experiencing a sudden or urgent need to urinate
Blood in your urine
Experiencing regular urinary tract infections (UTIs)
Pain or stinging when urinating

If you have a sudden inability to pass urine, seek urgent medical attention as soon as possible.

What a Bladder Ultrasound Can Diagnose

Ultrasound scans of the bladder can be used to diagnose the following:

Urinary Retention - the inability to pass urine or fully empty the bladder, sometimes caused by a blockage in the bladder, ureters or urethra
Bladder Stones - small mineral deposits that can form in the bladder, often associated with recurrent infections and incomplete bladder emptying
Bladder Tumours - abnormal growths in the bladder that can cause blockages and can be cancerous (malignant) or non-cancerous (benign)
Bladder Wall Thickening - an abnormal thickening of the bladder wall, caused by infections and inflammation that can lead to painful urination
Bladder Diverticula - sacs or pouches that develop on the bladder wall, which often cause no symptoms but can sometimes lead to frequent urination and infections
Ureterocele - an abnormality in the ureter, causing it to balloon and cause a blockage, and is present at birth
Cystitis - a type of UTI caused by bacteria in the urinary tract
Neurogenic Bladder - a condition that causes difficulty with bladder control caused by nerve or brain damage
Vesicoureteral Reflux - a condition that causes urine to travel back to the ureters and kidneys from the bladder, and is often present at birth
Hematuria Investigation - carried out to investigate the cause of frequent blood in the urine

Types of Bladder Ultrasounds

There are various types of bladder ultrasound - which one you have will depend on your symptoms and medical history:

Transabdominal Bladder Ultrasound

A transabdominal bladder ultrasound scan is the standard type of bladder scan. An ultrasound probe is moved over the lower abdomen/pelvic area to create ultrasound images of the bladder and surrounding soft tissues and organs.

Post-Void Residual Ultrasound

A post-void residual ultrasound, or PVR, is used to view how much urine is left in the bladder after urinating. It’s used to diagnose urinary retention, or an inability to empty the bladder.

Point-of-Care Bladder Ultrasound

A point-of-care, or bedside, bladder ultrasound is carried out on patients who are unwell or unable to get up from their beds. It can quickly diagnose sudden, or acute, urinary retention caused by a blockage in the bladder that requires urgent medical treatment.

Doppler Ultrasound of the Bladder

A Doppler ultrasound of the bladder works in the same way as a standard transabdominal ultrasound, but uses special equipment to specifically visualise the blood vessels and blood flow to and from the bladder. Doctors use a Doppler ultrasound when they want to diagnose or rule out inflammatory conditions or bladder tumours that may be restricting blood flow. It can also assess urine flow to and from the bladder.

3D Bladder Ultrasound

A 3D bladder ultrasound is a specialised bladder scan that gives detailed, three-dimensional information on the size, shape and volume of the bladder and its internal structures.

Contrast-Enhanced Bladder Ultrasound (CEUS)

A contrast-enhanced bladder ultrasound, or CEUS, is another type of specialised ultrasound that uses tiny (smaller than the size of blood cells) microbubbles of gas to enhance the images produced by an ultrasound scan. The microbubbles are injected into the bloodstream via an IV drip in your arm. Sound waves from the ultrasound transducer are reflected off the microbubbles, creating very light areas in the image that can be used to assess the function of the bladder and surrounding blood vessels.

Intraoperative Bladder Ultrasound

Intraoperative bladder ultrasound, or IOUS, is used to guide surgeons performing surgical procedures on the bladder to ensure they’re in the precise position they need.

How an Ultrasound of the Bladder Works

An ultrasound machine uses a probe called a transducer to send high-frequency sound waves through the skin into the body to create images of the soft tissues, bones and fluids in real time.

You won’t be able to feel or hear the sound waves as they enter the body. However, when they reach the organs, fluids, soft tissues and dense bones, they reflect back to the transducer to create black and white images that are then used to detect abnormalities.

To assist the transducer, a special water-based conductor gel is placed onto the skin to help transmit the sound waves from the probe into the body. This can feel cold when it is applied.

Equipment Used

An ultrasound machine is a small piece of equipment situated on a trolley, with a screen and a transducer probe attached. Many people would recognise an ultrasound machine as one that’s used to scan pregnant people. The equipment is generally the same for all types of diagnostic and pregnancy scanning ultrasound scans, but different transducer types and software programmes can be added.

Benefits

Ultrasound scans are quick, non-invasive, painless and safe. Unlike x-rays and CT scans, they don’t require the use of ionising radiation, and therefore don’t pose any radiation exposure risks.

Risks & Side Effects

There are no known risks or side effects caused by having an ultrasound scan. However, you may experience some pain or discomfort from having a full bladder when the ultrasound probe is pressed down onto your lower abdomen.

How to Prepare for a Bladder Ultrasound

Bladder ultrasound scans require little preparation. You’ll just need to drink plenty of fluid, around 500ml (half a litre), around half an hour before your scan (without emptying your bladder), as the scan works best with a full bladder. It’s also helpful to wear loose-fitting clothing to your appointment.

The Procedure Explained: What to Expect

Clinics and hospitals vary, but generally, an ultrasound of the bladder is carried out in the following way:

Explanation of Procedure - Your sonographer will explain the procedure to you and answer any questions or concerns you may have.
Bladder Filling Instructions - You’ll then be given 500ml of fluid to drink, if you haven’t already done so. You won’t be able to go to the toilet until your sonographer tells you that it's ok to do so.
Positioning on Exam Table - For a bladder ultrasound, you’ll be asked to lie down on your back on a medical couch. You may be asked to pull your lower clothing down (or remove it if it’s too tight). Your sonographer will cover your lower pelvis with a blanket or tissue.
Application of Ultrasound Gel - They will then apply a generous amount of ultrasound gel to your lower abdomen.
Transabdominal Scanning - Your sonographer will then press the ultrasound transducer onto the skin of your lower abdomen using a gentle but firm pressure, and move it around the area until the bladder comes into view.
Image Capture and Measurements - They will continue to move the ultrasound probe around your pelvic area and lower abdomen (in the region between your belly button and your pubic bone), regularly pausing and using the ultrasound machine to capture images and take measurements of the bladder and the bladder wall. They may ask you to hold your breath for a few seconds at various times.
Possible Post-Void Residual Scan - Depending on your symptoms, you may need to visit the toilet to empty your bladder and then have another ultrasound to see how efficiently your bladder is at fully emptying.
Completion and Clean-Up - Your sonographer will ensure they have enough high-quality ultrasound images, then they’ll remove the ultrasound gel with tissue, and you’ll be able to get dressed.
Discussion of Preliminary Results - If your bladder scan shows anything immediately of concern, your medical team may discuss some early results with you. If not, they’ll let you know when to expect a call or an appointment to discuss the outcome and possible treatment options.

What Happens After a Bladder Ultrasound?

After your bladder scan, you’ll be able to get dressed and return home and to your normal duties the same day.

Getting the Results

Your sonographer will send your ultrasound images to a specialist doctor called a radiologist, who will look at the structure and function of your bladder and assess any abnormalities. They will then send the results to your GP or referring doctor, who will contact you to discuss them and any treatment or next steps.

How Much Does a Bladder Ultrasound Cost?

In the UK, a private bladder scan starts at around £100. Most clinics will organise a pelvic ultrasound, rather than just a bladder scan. A pelvic ultrasound includes the bladder and the surrounding structures and organs to get a full picture of the health of your bladder and lower urinary tract.

Get a Bladder Ultrasound

It can be upsetting and worrying if you begin to develop symptoms that affect your bladder and urinary tract. The waiting time for a bladder scan on the NHS may be some weeks or longer.

If you’re concerned, book a private pelvic ultrasound with us, and your chosen expert medical team will take ultrasound images of your bladder and the surrounding structures and organs in your pelvic cavity so that they can discover what’s causing your symptoms.

FAQs

What Other Tests Can Diagnose Bladder Problems?

Various tests can diagnose bladder problems, including a procedure called a cystoscopy. During a cystoscopy, your doctor will pass a long, thin camera with a light on the end into your urethra and up into your bladder to view it from the inside.

You may have a cystoscopy as well as or instead of a bladder ultrasound. In some cases, your doctor may take a sample of tissue called a biopsy from your bladder during a cystoscopy to test it for the presence of abnormal cells that may indicate cancer.

Depending on your symptoms, you may also have a different type of scan to take images of your bladder, such as an MRI or a CT scan, as well as an ultrasound.

Why Do You Need a Full Bladder for an Ultrasound?

Yes, you will need to have a full bladder so that your ultrasound scan produces the most useful diagnostic images.

Does a Bladder Ultrasound Show Cancer?

Yes, an ultrasound of the bladder can show tumours that may indicate cancer. You’re likely to have further bladder scans and tests to definitively diagnose, or rule out, bladder cancer if a bladder ultrasound highlights a potential tumour.

How Long Does It Take to Fill Your Bladder for an Ultrasound?

You should follow the advice given by your doctor, but as a guide, you’ll need to drink 500ml of water, 30 minutes before your bladder ultrasound scan, to ensure your bladder is full.

Can Bladder Cancer Be Missed on an Ultrasound?

Some small or hidden bladder tumours may be missed on an ultrasound scan. If your doctor gives you a negative ultrasound result, yet you’re still experiencing symptoms, they may suggest a further scan or a cystoscopy.

How Long Does a Bladder Ultrasound Take?

A bladder ultrasound takes around 10-20 minutes, but you should allow an hour for your appointment.

References

Kidney and bladder ultrasound scan - Overview. (n.d.). Guy’s and St Thomas’ NHS Foundation Trust. https://www.guysandstthomas.nhs.uk/health-information/kidney-and-bladder-ultrasound-scan

Bsn, R. Z. R. (2022, March 5). What you need to know about bladder ultrasounds. Healthline. https://www.healthline.com/health/bladder-ultrasound

Urinary retention. (2025, June 2). Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/15427-urinary-retention

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