RESUMEN
Phlebectasia is an abnormal dilatation of an isolated vein and a rare venous anomaly and is usually asymptomatic. Internal jugular phlebectasia is a localized, nonpulsatile, nontender, compressible, and saccular or fusiform dilatation that enlarges with Valsalva maneuver, sneezing, coughing and straining which increases intrathoracic pressure. Internal jugular phlebectasia predominantly affects young children and its etiology is idiopathic in most cases, but several predisposing factors have been suggested. Although histopathological findings of most cases had no significant abnormality, those of some cases showed elastic dysplasia, focal intimal thickening and muscular defect within the wall of the vein. A swelling in the neck which enlarges with Valsalva maneuver must be differentiated from other diseases. Internal jugular phlebectasia is most likely to be mistaken for laryngocele, superior mediastinal cyst or branchial cleft cyst. Diagnosis should be as non-invasive as possible because no treatment is indicated for this benign self-limiting condition. We present a case of bilateral internal jugular phlebectasia of which diagnosis was made by sonography with doppler technique and neck CT.