Patent ID: 7410480

Claim:
A method for delivering a substance to a location within a head of a subject, said method comprising: introducing an implantable substance delivery reservoir comprising an expandable reservoir body in an unexpanded configuration through a nostril of the head, wherein the reservoir is removably coupled with an elongate shaft having a lumen in fluid communication with the reservoir; positioning the implantable reservoir at a desired location within a paranasal sinus or paranasal sinus ostium of the head; introducing a therapeutic or diagnostic substance, or a component thereof, through the lumen of the elongate shaft and into the reservoir causing expansion of the expandable reservoir body; detaching the elongate shaft from the implantable reservoir; and removing the elongate shaft from the head, thus leaving the implantable reservoir behind such that the therapeutic or diagnostic substance will pass out of the reservoir through at least one aperture located in the expandable reservoir body; preventing the diagnostic or therapeutic substance from backflowing out of the reservoir after removal of the elongate shaft.