Iliac Vein Compression- The May-Thurner Syndrome Diagnosed by CT Angiography

Chronic venous insufficiency and venous ulcers are a frequent cause of morbidity in diabetic as well as non-diabetic patients. Pelvic veins can often be involved by thrombosis. Imaging with Doppler sonography is essential to diagnose venous thrombosis. However, pelvic vein compression by an adjacent coursing artery is an unusual cause of lower limb venous obstruction, limb swelling and non-healing ulcers. Diagnosis of iliac vein obstruction and identification of compression by the iliac artery requires radiological imaging, with CT angiography being the current favoured modality. Here, a case 23-year-old male presented with painless swelling of the left leg since three years duration with a venous ulcer on the lateral aspect of lower leg since two years. In order to ascertain the cause of pelvic iliac vein compression(as detected on Venous Doppler ultrasonography), Dual-phase thin-section abdominal and bilateral lower limb Computed Tomography (CT) Angiography with venography run were performed, which showed the right common iliac artery compressing the left common iliac vein at its origin Based on these imaging findings, a radiological diagnosis of May-Thurner syndrome was made which highlights that non-thrombotic occlusion of pelvic veins can be a cause of unilateral lower limb swelling and long standing venous ulcer.