@Rad1 First a disclaimer. I am not a doctor nor a radiologist and all my assertions here need to be established with proper imaging and verified by a trained radiologist or doctors. Secondly, assuming that the recent Catheter Angiogram ruled out DAVFs such as cavernous DAVF and other vascular malformations, I think the limited images you shared show what appears to be Jugular Vein Reflux. That is usually indicated in imaging as hyperintensities on the Jugular Vein. The brightness shows in-flow instead of outflow of blood (as pointed by the large cyan arrow below images). Normally Jugular Vein carries blood out of the head and towards the heart but in cases where there is compression or obstruction in the central veins such as left brachiocephalic vein/Vena cava, the blood refluxes back to the Jugular vein and back to the head area causing facial pain, breathlessness sensation, neck/face swelling, tachycardia, temperature changes and blueish lips due to deoxygenated blood backing up to the veins of the head and neck. This correlates with your symptoms of facial pain and the engorged/dilated veins of the face such as facial vein/Superior Ophthalmic Vein that was causing pain prior to the craniotomy. It is mainly caused by left brachiocephalic vein compression between the Aorta and the Sternum so if you have chest CT scan, we can establish that is the case. There was one of our fellows here called @DogLover who suffered this type of compression and we talked about her case here (Dilated Collaterals Cause Progressive Weakness on All Limbs as result of Bilateral Jugular Vein Occlusion - Interesting IJV Bypass Treatment - #37 by DogLover) if you want to read her case more. That link has it all.
So this is the suspicion I have but in order to establish it, we need chest contrast CT at the level of the Aorta to see if that is the case. I do not think CT of neck and head go all the way to that level. Also keep in mind that sometimes, Cavernous DAVF or cDAVF as it is known can mimic Jugular Vein Reflux from BC compression as this article (MRI and MR Angiography Findings to Differentiate Jugular Venous Reflux From Cavernous Dural Arteriovenous Fistula : American Journal of Roentgenology : Vol. 202, No. 4 (AJR)) detailed how to differentiate the two.
Big Cyan Arrows pointing what I believe to be hyperintensities in the Jugular Vein potentially caused by retrograde blood flow.
