Compression of the left common iliac vein in asymptomatic subjects and patients with left iliofemoral deep vein thrombosis.

PURPOSE

To retrospectively evaluate compression of the left common iliac vein as demonstrated at computed tomography (CT) in patients with iliofemoral deep vein thrombosis due to iliac vein compression syndrome (IVCS) and compare compression ratios with those of asymptomatic subjects.

MATERIALS AND METHODS

Between March 2003 and June 2007, compression of the left common iliac vein by the right common iliac artery, as demonstrated with CT, in 34 patients (25 women and nine men; mean age, 51 years; age range, 21-79 years) with IVCS was retrospectively evaluated. Compression ratios were compared with those of 34 age- and sex-matched asymptomatic subjects. A t test was used to compare the compression ratios.

RESULTS

The percentages of compression of the left common iliac vein were 45%-100% (mean, 74% +/- 17) for patients with IVCS and 0%-68% (mean, 28% +/- 20) for control subjects (P < .05). Of the 34 patients with IVCS, 11 (32%) had less than 70% compression and 23 (68%) had at least 70% compression.

CONCLUSIONS

There was considerable overlap between the degree of compression in patients with IVCS and control subjects. Compression of the left common iliac vein was significantly more prominent in patients with lower extremity deep vein thrombosis due to IVCS when compared with control subjects. Compression in excess of 70% as demonstrated at CT can be helpful for identifying possible underlying IVCS in patients with a left lower extremity deep vein thrombosis.