In most cases, the diverticulum is not the primary problem. The primary problem is venous sinus stenosis. The stenosis results in increased flow velocity across the area of narrowing — just like pinching a water hose makes water travel further. This jet of fast flow in the sinus impacts the temporal bone where the sinus lives — and over years remodels it to make a diverticulum — just like dripping water will over time make a hole in stone.
One diverticulum forms it can contribute or even cause PT. Closing the diverticulum is easiest done in an endovascular way — by coiling for example. It can also be done surgically. Often the diverticulum and the causative venous sinus stenosis are treated together with stenting and coiling — to maximize the chance of success.
Here is an example of a really large diverticulum, remodeling the temporal bone, on a “DYNA CT” — modern angiographic version of temporal bone CT
The angiogram shows the diverticulum (arrows). However, the primary problem is the stenosis (dashed arrows). The direction of blood flow, impacting temporal bone and sculping out the diverticulum, is shown by open arrow
Cross eye stereo pair images of the same patient