About this test
Colour Doppler shows the direction and speed of blood flow inside vessels. It is added to an ultrasound when a doctor needs to know whether an organ is receiving enough blood, or whether a vessel is narrowed, blocked or dilated.
When is it advised?
- Renal Doppler: high blood pressure that may come from narrowed kidney arteries, or kidney problems
- Scrotal Doppler: varicocele, testicular pain or swelling
- Portal venous Doppler: liver disease and portal hypertension
- Pelvic Doppler: ovarian or uterine conditions, when advised
- Penile Doppler: evaluation of erectile dysfunction, on a urologist's advice
How to prepare
- Renal and portal Doppler: 4–8 hours without food (overnight is best); keep the last meal light and low in fat.
- Other Doppler studies need no special preparation — you will be told when booking.
On the day
- A female staff member (chaperone) is always present during the scan.
- Bring your doctor's prescription or referral slip, a photo ID and any previous reports.
- Most scans take about 10–20 minutes on the table.
- The report is prepared by the radiologist, handed to you and also shared on WhatsApp.
Frequently asked questions
How is a Doppler different from a normal ultrasound?
A normal ultrasound shows structure; Doppler adds information about blood flow. It is done with the same machine during the same visit.
This page is general information, not medical advice. Your doctor will decide which test is right for you.