Artificial intelligence-assisted ultrasound
Topic Status Complete
Artificial intelligence-assisted ultrasound for the detection of deep vein thrombosis
Outcome of the appraisal
More evidence is needed on ThinkSono Guidance for the detection and diagnosis of deep vein thrombosis. Based on the evidence reviewed, the proposed pathway using ThinkSono Guidance is associated with worse diagnostic accuracy compared with usual care.
The cost effectiveness of the proposed pathway was uncertain because the price of ThinkSono Guidance had not been finalised, and model estimates were sensitive to the choice of inputs and assumptions.
Why was this topic appraised?
Deep vein thrombosis (DVT) is a blood clot in a vein and usually occurs in the leg. If part of the blood clot breaks off and travels to the lungs, it can be extremely dangerous. Currently, detection and diagnosis of DVT is done by specialists, such as a sonographer or a radiologist, at a hospital involving a duplex ultrasound scan. However, in the current care pathway there are delays in ultrasound, which could lead to an increased use of interim anticoagulation medication.
It has been proposed that artificial intelligence (AI) assisted ultrasound can support a more efficient diagnosis of DVT. The ThinkSono Guidance system (AutoDVT with clinician review) uses an AI smartphone application and a handheld ultrasound device at the point of care. It can be performed by non-specialists and could in theory enable a quicker diagnosis when added to the current care pathway. The proposed use of ThinkSono Guidance is as a proximal DVT rule-out tool, by prioritising the positive and indeterminate cases as high-risk to obtain a follow-up ultrasound within four hours as per the National Institute for Health and Care Excellence (NICE) recommendations.
This topic was submitted by the manufacturer of the ThinkSono Guidance system, via the NHS Innovation Service.
Lay summary
What is deep vein thrombosis (DVT)?
Deep vein thrombosis, or DVT, happens when a blood clot forms in a deep vein and slows or blocks blood flow. Main symptoms include:
- Swelling in the leg
- Pain or tenderness
- Red or darker skin
- Warm skin over the vein
- Swollen or bulging veins
DVT usually affects the legs, but clots can form in other parts of the body.
Why is DVT serious?
If part of the clot breaks away, it can travel to the lungs. This is called a pulmonary embolism. It is life-threatening and needs urgent treatment.
Who is at risk?
Anyone can develop a DVT, but some factors make it more likely:
- Getting older
- Sitting still or being inactive for long periods
- Having damaged blood vessels
- Taking certain medicines
- Pregnancy
How is DVT normally diagnosed?
Doctors usually use two tests: a blood test to look for signs of a clot and a hospital ultrasound scan, in which a specialist checks how well blood is flowing through the veins.
What is AI ultrasound?
Artificial intelligence (AI) can be built into small, handheld ultrasound devices. These can be used by staff who are not ultrasound specialists, such as in GP surgeries or community clinics. The AI helps the user to check if a clot might be present. This means people at higher risk can be identified sooner and treated faster.
What did Health Technology Wales look at?
Health Technology Wales searched for evidence on using AI-assisted ultrasound for detecting DVT. More evidence is needed before a recommendation can be made.
Guidance
GUI073 02.2026
Evidence Appraisal Report
EAR073 02.2026
Topic Exploration Report
TER593 05.2025 (superseded by EAR073 02.2026)
Health Technology Wales Partners
