Sigmoid Sinus Diverticulum

Sigmoid sinus diverticulum is a rare vascular finding due to an opening in the bone at the area of the sigmoid sinus creating a pouch, or diverticulum. Sometimes, there may be associated stenosis. The diverticulum may present as pulsatile tinnitus. Several case reports have demonstrated that treatment or endovascular coiling of this diverticulum can provide relief for a patients' symptoms. 

Diagnosis

Sigmoid sinus diverticulum can be diagnosed either by CT, CTA, MRI or MRV. Cerebral angiography provides definitive diagnosis

Axial CT: Right sigmoid sinus diverticulum

Venogram, showing right sigmoid sinus diverticulum

Venogram, after coiling of the pouch, the diverticulum is closed