If you've ever wondered why your sonographer seems to lean into the probe during an abdominal scan, you're not alone. The pressure is deliberate — and here's what it achieves.
The Enemy: Bowel Gas
Ultrasound cannot see through gas. Your intestines naturally contain pockets of it, and these sit directly in front of deep structures like the pancreas, aorta, and parts of the kidneys. Firm, graded pressure gently pushes gas-filled bowel loops aside, opening a clear acoustic window to what's behind them.
Other Reasons for Pressure
- Reducing distance: Sound waves weaken as they travel. Compressing the tissue brings the probe closer to deep organs, sharpening the image.
- Testing compressibility: In leg vein scans, pressing is the actual test — healthy veins squash flat; veins containing a clot don't.
- Checking tenderness: If gallbladder or appendix disease is suspected, pain under direct probe pressure (a "sonographic Murphy's sign") is genuinely diagnostic information.
- Stabilising moving targets: Pressure helps hold structures steady for accurate measurement.
When to Speak Up
Firm should never mean unbearable. Tell your sonographer if:
- Pain is sharp rather than just uncomfortable
- You're pregnant and the pressure worries you (obstetric scans use much lighter pressure)
- You have a hernia, recent surgery, or a tender mass in the area
Pressure can almost always be moderated while still getting diagnostic images.
This article is for general information only and is not a substitute for professional medical advice.
Ready to Book Your Ultrasound Scan?
Mascot Healthcare Clinic, Akoka (Yaba), Lagos offers ultrasound scans by appointment only, Monday–Saturday, 9am–5pm. Book online and choose a time that works for you.