I was referring the CT on the posting below. I did assume it was CTV ( CT Venography) since it clearly showed the venous systems well. If it was CTA ( CT Angiography), then it must have been done in both phases ( venous & arterial) since IJVs and collaterals (which are veins) are clearly seen. Typically, CTA will show arteries clearer than veins.
Well, it is bit difficulty to glean evidence from a video but if your thick black lines along the optical nerve is all CSF, then there is no doubt that the Optic Nerve Sheath is dilated although it is bit difficulty to visualize in T1.
For Meckel Cave, according to the paper I posted "The mean diameters of the Meckel cave on the coronal T2 plane in patients with idiopathic intracranial hypertension were 5.21 ± 1.22 mm on the left side and 5.16 ± 0.90 mm on the right side ". That means the diameter could be as low as 4.26 mm and as high as 6.06 mm on the right side, my guess is, that your right Meckel Cave falls in that range with my visual estimation because it is difficulty to measure it on a video.
T2/Fiesta sequences with more slices than the traditional 27 slice, is good for measuring them.