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
Treatment
If no other source is found for the patient's symptoms of pulsatile tinnitus, treatment of the diverticulum via endovascular coiling, if found on the same side of the patient's symptoms, can provide relief in reducing or eliminating this sound.
References
1. Srinivasan Paramasivam, Sunil Furtado, Tomoyoshi Shigamatsu, Eric Smouha. Endovascular Management of Sigmoid Sinus Diverticulum. Interv Neurol. 2016 Jun; 5(1-2): 76–80.