Ultra miniature pressure sensor

Abstract

A method of measuring blood pressure and velocity proximally and distally of a stenosis in a vessel carrying blood includes the steps of providing a guide wire having both a pressure sensor and a velocity sensor disposed on a distal region of the guide wire, introducing the guide wire into the vessel, advancing the guide wire to position the pressure sensor and the velocity sensor proximally and distally of the stenosis, and measuring the blood pressure and velocity proximally and distally of the stenosis with the pressure sensor and the velocity sensor.

1 . An apparatus for measurement of a flow characteristic comprising: 
 a guidewire having a diameter of 0.018″ or less;    a solid state pressure transducer;    a housing, wherein the solid state pressure transducer is disposed at least partially within the housing; and    an opening within the housing which is sized so that ambient fluid is allowed to enter but non-flowing material is not allowed to enter.