Sonographic diagnosis of a saccular aneurysm of the internal jugular vein.

Aneurysm of the internal jugular vein is an extremely rare condition. It is usually detected during childhood and is characterized by being more prominent during Valsalva maneuvers such as vomiting, coughing, and straining. Most of the cases reported in the English literature are fusiform aneurysms of the internal jugular vein. We report the case of a saccular aneurysm of the left internal jugular vein in a 59-year-old woman with no change in size of the aneurysm during a Valsalva manuever.