“Does a CT scan show varicose veins?”

varicose veins and venous insufficiency is best diagnosed with venous insufficiency ultrasound by a qualified vascular technologist and read by a physician trained with vascular credentials

Not really. A CT can show large veins, but varicose veins are the result of blood moving the wrong way in the veins. An ultrasound will show blood moving in the veins and demonstrate reflux.

One does not need a CT scan to see varicose veins on the legs. However, sometimes a CT scan of the pelvis may be obtained to evaluate pelvic varicosities as seen in chronic pelvic venous congestion. This is it and it's perfect! Make it a great day.

It can show varicosities in the chest , abdomen and extremeties.

Ultrasound is the standard of care for diagnosing venous problems. If the Provider is concerned with possible pathology in the pelvis or abdomen as an underlying cause for venous issues, they may order a CT venogram. It may be able to help determine the anatomy and level of pathology. CT scans can be ordered for persistent concerns along with Ultrasound to find deep, hidden varicose veins and even the root disorder in lower body circulation behind the symptoms in patients with varicose veins.
This is not my area of practice. Most specialists can explain in detail the appropriate exam for your condition.