What is the rationale in myelography positioning?

Question

In myelography, why is it you are placed in a fowlers position when water based dye is used and flat on bed when oil based dye is used?

Answer 1

I'm haven't seen oil-based contrast agents used in myelography in my experience.  The rationale for keeping the patient in a fowler's position or any position where the head is kept up is simply to limit the amount of radiocontrast flowing cranially as this can cause cephalgia, so for this reason it's prudent to keep the radiocontrast in a gravity-dependent position.

And even more fundamentally, we'd like to ensure that the patient doesn't move excessively such that a platelet plug can form properly and avoid intrathecal hemorrhage.