More time to develop than arteries (80 mm is adult stage)
Evolution occurs post-natally
Telencephalon develops faster than rest of brain --> displaces veins posteriorly Reason why cortical veins drain UP to SSS
Uneven development: SSS --> Torcula --> predominant R Straight sinus --> Torcula --> predominant L
Pro-otic sinus --> cavernous sinus & inferior petrosal sinus (initially just craniofacial drainage) Veins draining into cavernous sinus may connect via alternative means
Basal vein of Rosenthal Fragmented genesis Connects late to Galenic system (up to 80 mm stage)
