Kidney structure
Kidney size, position, contour, cortical appearance and visible structural abnormalities.
Kidney, urinary tract & bladder ultrasound • London & St Albans
Private kidney and urinary tract ultrasound
A focused, radiation-free assessment of both kidneys and the urinary bladder, including ureters when visible and bladder emptying with a post-void residual measurement.
- No GP referral required
- Full bladder required
- Written report with images
Illustrative anatomy only — the actual examination uses real-time diagnostic ultrasound.
Kidney & urinary tract scan£219Self-referral available
Both kidneysSize, structure, cysts, masses, stones and drainage
Urinary bladderWall, contents, capacity, stones and focal findings
Post-void residualAssessment of how effectively the bladder empties
Radiation-freeNon-invasive real-time ultrasound imaging
About the examination
What is a kidney and urinary tract ultrasound?
A kidney and urinary tract ultrasound—also called a renal tract, kidney and bladder, or KUB ultrasound—uses high-frequency sound waves to assess the urinary system without ionising radiation.
The examination evaluates both kidneys and the bladder. The ureters are assessed where visible, particularly if they are dilated. A full bladder allows the practitioner to assess bladder capacity and the bladder wall before you urinate, followed by a post-void measurement to estimate any urine remaining.
It can support the investigation of urinary symptoms, flank pain, suspected stones, recurrent urinary infections, blood in the urine, abnormal renal blood tests, known cysts and concerns about incomplete bladder emptying.
Scan coverage
What the examination assesses
The exact scope is tailored to your symptoms, medical history and any previous investigations.
Stones & obstruction
Visible renal calculi, hydronephrosis and secondary signs suggesting impaired urinary drainage.
Cysts & focal findings
Assessment for simple or complex cystic findings and visible solid masses requiring further evaluation.
Ureters when visible
Dilated proximal ureters, ureteric jets and indirect features of obstruction where technically assessable.
Bladder assessment
Bladder volume, wall, internal debris, diverticula, stones and visible focal lesions.
Bladder emptying
Pre-void and post-void bladder volumes to estimate residual urine after urination.
Prostate impression
In men, the transabdominal appearance or impression at the bladder base may be noted when relevant.
Doppler when indicated
Limited Doppler assessment may be used where clinically relevant; renal artery stenosis requires a dedicated Doppler service.
Important: Normal ureters are frequently not visible. A dedicated prostate, renal artery Doppler, pelvic or abdominal examination is not automatically included unless stated in your booking.
Renal &
bladder imaging
bladder imaging
Real-time • Non-invasive • Radiation-free
When it may help
Common reasons to book
- Flank, loin or lower abdominal pain
- Suspected kidney stones or renal colic
- Visible or microscopic blood in the urine
- Urinary frequency, urgency, poor stream or incomplete emptying
- Recurrent urinary tract infections
- Abnormal kidney-function blood tests
- Follow-up of known renal cysts or hydronephrosis
- Post-void residual or urinary-retention assessment
Seek urgent medical care for inability to pass urine, severe worsening pain, fever with flank pain, vomiting, collapse, significant visible bleeding, or symptoms of sepsis. Private ultrasound is not an emergency service.
Before you arrive
How to prepare for your scan
Drink still water
Drink approximately 500–750 ml of still water 45–60 minutes before your appointment, unless your confirmation gives different instructions.
Keep your bladder full
Try not to urinate before the first part of the scan. Arrive comfortably full rather than painfully overfilled.
No fasting usually needed
A kidney-and-bladder-only scan normally does not require fasting. Combined abdominal scans may have separate fasting instructions.
Bring clinical information
Bring relevant urine or blood-test results, medication details, referral letters and previous ultrasound, CT or MRI reports when available.
Difficulty holding urine? Tell the clinic in advance if you have urinary retention, heart or kidney fluid restrictions, diabetes, mobility difficulties, or cannot safely follow standard drinking instructions.
Your appointment
What happens during the scan?
- 1
Clinical discussion
Your practitioner confirms your symptoms, urinary history, previous infections or stones, relevant tests, medication and the focus of the examination.
- 2
Scan with a full bladder
You lie on the examination couch while gel and a handheld probe are used over the abdomen, sides and back. You may be asked to change position or briefly hold your breath.
- 3
Empty your bladder
After the first images and bladder-volume measurement, you are usually asked to use the toilet.
- 4
Post-void measurement
The bladder is rescanned to estimate the residual urine volume and assess how effectively it has emptied.
- 5
Results and report
The main observations may be explained in clear language, followed by a written report with relevant images and recommendations.
Understanding the scope
Important ultrasound limitations
Ultrasound is a valuable first-line test, but it cannot answer every urinary question.
Urinary infection
Ultrasound may identify causes or complications of infection, but a UTI is diagnosed using symptoms, clinical assessment and urine testing.
Ureteric stones
Small or distal ureteric stones can be difficult to see. Hydronephrosis or ureteric dilatation may provide indirect evidence, and CT may be recommended.
Haematuria and bladder lesions
Ultrasound may identify a visible mass but does not replace a complete haematuria pathway. Persistent blood in the urine may require cystoscopy and/or CT urography.
Choosing the right service
Kidney ultrasound or another urinary scan?
| Kidney & urinary tract scan | Both kidneys, bladder, ureters when visible, and pre-/post-void bladder volumes. |
|---|---|
| Dedicated prostate scan | More focused assessment of prostate size, contour and bladder outlet, according to the selected service. |
| Renal artery Doppler | A specialised vascular examination for suspected renal artery stenosis or renovascular hypertension. |
| Abdomen + urinary tract | Extends the assessment to upper-abdominal organs and usually requires fasting as well as a full bladder. |
| CT or MRI | May be recommended for small ureteric stones, complex masses, persistent haematuria or findings not fully characterised by ultrasound. |
PrivateSono
Focused urinary imaging with clear reporting
Book a self-referred kidney and urinary tract ultrasound at our Central London or St Albans clinic, with a structured examination and appropriate recommendations.
Book kidney & urinary scan — £219Experienced practitioners
Examinations performed by appropriately trained ultrasound professionals.
Modern equipment
Real-time diagnostic imaging with measurements and Doppler when indicated.
Clear communication
Principal observations explained clearly with a structured written report.
Flexible access
Online booking and self-referral across two clinic locations.
Clinic locations
Kidney and bladder ultrasound near you
Good to know
Kidney and urinary tract FAQs
Answers to common questions about preparation, scan coverage, results and limitations.
Still unsure? Call 020 7101 3377What does a kidney and urinary tract ultrasound examine?
The examination assesses both kidneys and the urinary bladder. The upper ureters may be assessed when visible, especially if dilated. Bladder volume and post-void residual urine can also be measured.
Why do I need a full bladder?
A comfortably full bladder provides a clearer acoustic window, helps the practitioner assess the bladder wall and capacity, and allows pre-void and post-void measurements.
How much water should I drink?
Drink approximately 500–750 ml of still water 45–60 minutes before the appointment and try not to urinate. Follow the exact instructions in your booking confirmation, as individual requirements may vary.
Do I need to fast?
Fasting is not usually required for a kidney-and-bladder-only examination. You may be given different instructions if the urinary scan is combined with an abdominal ultrasound.
Can ultrasound diagnose a urinary tract infection?
Ultrasound does not directly diagnose a UTI. It may identify contributing factors or complications such as retention, stones, obstruction or hydronephrosis. Urine testing and clinical assessment are usually needed.
Can the scan detect kidney stones?
Many kidney stones can be identified, particularly stones within the kidneys that produce characteristic ultrasound features. Very small stones and some ureteric stones may not be visible, so further imaging may sometimes be recommended.
Will the ureters always be seen?
No. Normal ureters are often difficult to visualise on ultrasound. Dilated ureteric segments or secondary signs of obstruction may be seen when present.
What is a post-void residual measurement?
The bladder is measured while full, after which you are asked to urinate. A second measurement estimates how much urine remains and helps assess bladder emptying.
Does the scan assess the prostate?
In men, the prostate may be seen transabdominally and its impression on the bladder base may be noted. A detailed prostate assessment is a separate service unless specifically included in the booking.
Is the examination painful or harmful?
The scan is non-invasive and does not use ionising radiation. Most people find it comfortable, although pressure from the probe can cause temporary discomfort over a painful area or a very full bladder.
Can I have the scan during pregnancy or menstruation?
Ultrasound does not use ionising radiation and may be performed during pregnancy when clinically appropriate. Menstruation does not usually prevent a transabdominal urinary tract scan.
How long does the appointment take?
The scan commonly takes around 15–20 minutes, although it may take longer if extra views, Doppler assessment or complex measurements are required.
When will I receive the report?
The principal observations may be discussed at the appointment, and a written report with relevant images is provided according to the clinic’s reporting process.
Do I need a GP referral?
No. PrivateSono accepts self-referrals. Please provide your symptoms, relevant medical history, medications, urine or blood-test results and previous imaging when available.
What happens if an abnormality is found?
The report may recommend discussion with your GP or urology team, urine or blood tests, interval ultrasound, CT, MRI, cystoscopy or another specialist investigation depending on the finding and your symptoms.
Appointments in London & St Albans
Ready to book your kidney and urinary tract ultrasound?
View appointment availability and confirm your scan online for £219.