BACKGROUND:
Even though color Doppler ultrasound (CDUS) imaging is reliable in assessing deep vein thrombosis (DVT) in lower extremities, anatomical variations of tibial veins may limit the diagnosis and even lead to false positive results.
OBJECTIVE:
To describe anatomic variations of the posterior tibial vein that may lead to false positive results in the CDUS diagnosis of chronic DVT.
METHODS:
CDUS scans of patients with suspected deep vein thrombosis of the lower extremities obtained from January to December 2012 were reviewed to record the presence, number and course of deep veins and arteries. Suspected anatomic variations of the posterior tibial veins were reviewed by another vascular sonographer to confirm findings. Anatomic variations, such as absence or hypoplasia of the posterior tibial veins, were recorded when the posterior tibial artery was not detected in any segments, as well as when the artery was also not visualized in the same segments.
RESULTS:
A total of 1458 CDUS scans of patients with suspected DVT in the lower extremities were reviewed. In six patients (0.41%), the posterior tibial veins were absent or hypoplastic. Scans were unilateral for five patients and bilateral for one, at a total of 7 lower extremities (3 right and 4 left).
CONCLUSION:
Although a rare condition, found in only 0.41% of the cases, awareness of posterior vein absence may help to avoid misdiagnoses and false-positive results of DVT in patients with this variation.
posterior tibial vein; vein thrombosis; ultrasound
