Can an ultrasound detect all kidney stones?

Ultrasound is excellent for detecting stones in the kidney (sensitivity ~80–90%) and identifying associated hydronephrosis. However, small ureteric stones (in the tube between the kidney and bladder) may not be visible on ultrasound. If a ureteric stone is suspected, a CT KUB (non-contrast CT of the kidneys, ureters, and bladder) may be recommended.

No. The scan is entirely painless. A gel is applied to the skin and a probe is moved over your abdomen and sides.

Do I need to fast before the scan?

Yes. Fasting for 4–6 hours before the scan reduces bowel gas, which can obscure the kidneys. Water is permitted and encouraged.

Can an ultrasound detect kidney cancer?

Ultrasound can detect renal masses and characterise them as cystic or solid. Solid renal masses require further characterisation with CT or MRI to assess for malignancy. If a suspicious mass is detected, your report will recommend appropriate urgent referral.

Do I need a GP referral?

No referral is needed. You can book directly online or by telephone. Same-day appointments are available Monday to Saturday.

Can both kidneys be assessed in one appointment?

Yes. Both kidneys are always assessed in the same appointment as standard. The scan takes 20–30 minutes.

HCPC Registered— All sonographers

CQC Compliant— Regulated clinic

Same-Day Available— Mon – Sat

Written Report— Within 24 hours

HCPC Registered

CQC Compliant

Same-Day Available

Written Report

Men's Health

Kidney Ultrasound Scan

Detailed ultrasound assessment of both kidneys and the surrounding structures to investigate pain, haematuria, recurrent infections, or abnormal blood test results.

20–30 minutes

Same-day appointments

Marylebone, London W1

HCPC RegisteredCQC CompliantSame-Day AvailableWritten Report IncludedDiagnostic Imaging Expert

£235

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4.9/5 from 600+ patients

HCPC-registered sonographers

Written report within 24 hours

Same-day appointments available

CQC-compliant clinic

Understanding Your Situation

Kidney Symptoms That Deserve a Clear Answer

Flank pain, blood in the urine, recurrent urinary infections, or abnormal kidney function blood tests — these symptoms can be worrying, and waiting weeks for an NHS scan can feel unbearable. A kidney ultrasound scan provides a clear, same-day assessment of both kidneys, detecting stones, cysts, hydronephrosis, and other conditions that may be causing your symptoms. In the UK, kidney stones affect approximately 1 in 10 people, and early detection significantly improves outcomes. Based at 29 Weymouth Street in Marylebone, Central London, we provide same-day appointments with written reports included.

Clinical Overview

What is a Kidney Ultrasound Scan?

A kidney ultrasound scan uses high-frequency sound waves to produce real-time images of both kidneys, the renal pelvis, and the proximal ureters. It assesses kidney size, shape, cortical thickness, and internal architecture, and detects abnormalities such as stones, cysts, hydronephrosis (swelling due to urine obstruction), and masses. The scan is painless, radiation-free, and produces immediate results. It is the first-line imaging investigation recommended by NICE for most renal symptoms.

Is This Scan Right for You?

Who Should Book This Scan?

Individuals with flank or loin pain suggesting kidney stones or infection

Patients with haematuria (blood in the urine) requiring investigation

Those with recurrent urinary tract infections needing structural assessment

Patients with abnormal kidney function blood tests (raised creatinine or eGFR)

Anyone with a known kidney cyst requiring monitoring

Patients with hypertension or diabetes needing renal assessment

Diagnostic Scope

What This Scan Can Detect

Kidney Stones (Nephrolithiasis)

Detection of calculi within the kidney collecting system, which cause severe colicky pain and haematuria. Ultrasound identifies stones and associated hydronephrosis.

Hydronephrosis

Swelling of the kidney due to obstruction of urine flow, which can be caused by stones, strictures, or external compression. Graded by severity.

Renal Cysts

Fluid-filled sacs within the kidney, classified using the Bosniak system from simple benign cysts to complex lesions requiring further investigation.

Renal Masses

Solid lesions within the kidney that may represent benign angiomyolipomas or renal cell carcinoma, requiring further characterisation with CT or MRI.

Chronic Kidney Disease Features

Reduced kidney size, increased echogenicity, and loss of corticomedullary differentiation — features of chronic kidney disease that correlate with renal function.

Your Appointment

What Happens During Your Scan

Preparation check

You will be asked about your symptoms, relevant blood test results, and any previous kidney investigations to focus the examination.

Supine assessment

With you lying on your back, both kidneys are assessed through the anterior abdominal wall, measuring size and assessing the collecting system.

Lateral decubitus views

You will be asked to roll onto each side to obtain lateral views of the kidneys, which often provide clearer images of the renal parenchyma and collecting system.

Doppler assessment

Colour Doppler evaluates blood flow to and within the kidneys, assessing for renal artery stenosis or areas of reduced perfusion.

Report & recommendations

All findings are explained immediately. A written report is provided before you leave, with recommendations for further investigation or management as appropriate.

Before Your Appointment

How to Prepare for Your Scan

1
Fast for 4–6 hours before the scan to reduce bowel gas (water is permitted)
2
Drink 500ml of water 30 minutes before your appointment to ensure adequate hydration
3
Wear comfortable, loose clothing that allows easy access to your back and sides
4
Bring any relevant blood test results (creatinine, eGFR, urine dipstick) if you have them
5
Allow 30–45 minutes for your appointment including discussion time

After Your Scan

Understanding Your Kidney Scan Results

Your sonographer will explain all findings immediately after the scan. Normal kidneys measure 9–12cm in length with smooth outlines and normal echogenicity. Abnormal findings — including stones, cysts, hydronephrosis, or masses — will be clearly described with their clinical significance and management recommendations. A written report is provided before you leave, suitable for your GP, urologist, or nephrologist.

Why Private?