connected to internal jugular vein inferior petrosal sinus The inferior petrosal sinus, within the human head, is an area beneath the brain, which allows blood veins to span the area, from the center of the head downward. It drains from the cavernous sinus (beneath the brain) to the sigmoid sinuses above the internal jugular vein. Wikipedia:Inferior_petrosal_sinus sinus petrosal inferior FMA:50770 UBERON:0007160 SCTID:279263009 EMAPA:19234 paired venous dural sinus