complicated question but what's being asked is that we talked about blood pressure being too high as a cause a stroke can blood pressure being too low because a stroke as well and the answer is yes that there certainly are situations particularly for patients who have you know major blockages of vessels where you know the plumbing is blocked up you can imagine if you don't have enough pressure you're going to run into trouble and typically the type of strokes we see from that are called watershed strokes where you have two