"While the function of the canal of Gratiolet is unknown, the canal may be a medium for the spread of intracerebral haemorrhage 2-7. Indeed, there are a few case reports 2,3,5,6 of patients with bilateral basal ganglia intracerebral haemorrhage where blood is seen, especially on susceptibility-weighted imaging (SWI), to involve the canal of Gratiolet, with the hypothesis being that haemorrhage may have been unilateral initially but then tracked through the canal of Gratiolet to involve the contralateral basal ganglia 2-7."