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Published on: June 2, 2015
May-Thurner syndrome: can it be diagnosed by a single MR venography study?
Shaunagh McDermott1, George Oliveira, Emel Ergül
1Department of Imaging, Division of Vascular Imaging and Intervention, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Purpose:
We aimed to evaluate the longitudinal stability of left common iliac vein (LCIV) compression by the right common iliac artery on magnetic resonance venography (MRV).
Materials And Methods:
This retrospective study included 214 patients diagnosed with May-Thurner syndrome by MRV. We identified a subset of patients who underwent contrast-enhanced cross-sectional imaging of the pelvis six months before or anytime after the MRV and did not undergo any interventional venous procedures between the two studies; 36 patients met these criteria. The degree of venous compression was calculated in both the index and comparison study.
Results:
On the index MRV, the mean compression of the LCIV was 62%. However, on the comparison study in the same patients, the mean compression was 39%. The mean change in degree of compression between the two studies was 23% (P < 0.0001), ranging from a 12% increase to 69% decrease in degree of compression on the comparison study.
Conclusion:
The compressed LCIV on a single MRV study was not stable over time and thus may be insufficient to diagnose May-Thurner syndrome.
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