Patent ID: 8231537

Claim:
A method for measuring blood pressure and a blood flow characteristic other than blood pressure at a region of interest in a vessel without restricting flow in the vessel, comprising the steps of: providing a flexible elongate member having a proximal end, a distal end, and an outer diameter of no greater than 0.018 inches, a pressure sensor secured to a distal region of the elongate member, and a sensor for measuring a blood flow characteristic other than blood pressure secured to the distal region of the elongate member, wherein the separation between the pressure sensor and the sensor for measuring a blood flow characteristic other than blood pressure is less than 3 cm; advancing the distal end of the elongate member to the region of interest; measuring blood pressure at the region of interest; and measuring a blood flow characteristic other than blood pressure at the region of interest simultaneous with the step of measuring blood pressure, wherein the region of interest comprises a vascular stenosis, and wherein the step of measuring blood pressure at the region of interest comprises measuring a first blood pressure distal the stenosis in a first flow state and measuring a second blood pressure in a second flow state; wherein the step of measuring a blood flow characteristic other than blood pressure at the region of interest comprises measuring a first blood flow characteristic other than blood pressure distal the stenosis in a first flow state and measuring a second blood flow characteristic other than blood pressure in a second flow state; and wherein the method further comprises determining a severity of the stenosis by at least one of the following steps: comparing the first blood pressure and the second blood pressure; and comparing the first blood flow characteristic other than blood pressure and the second blood flow characteristic other than blood pressure.