Patent ID: 9247909
Filing Date: 2016-02-02
CPC Classification: A61B

Claim Text:
1. A guidewire system, comprising: a guidewire including a distal end, a proximal end, an external surface, and a window located at or near the distal end, the guidewire having an inner lumen that extends from the window to the proximal end wherein the window exposes the external surface of the guidewire to the inner lumen of the guidewire, the external surface being continuous from the proximal end to the window so that no part of the inner lumen is exposed to the external surface between the proximal end and the window; a mating device having an inner lumen that is filled with a fluid, gel or any media that is virtually incompressible at physiological pressures and can transmit pressure and that is in fluid communication with the inner lumen at the proximal end of the guidewire, the mating device also having a chamber dimensioned to conformally receive and grip the outer surface of the proximal end of the guidewire; a pressure transducer in fluid contact with the fluid filled inner lumen of the mating device wherein the pressure transducer converts mechanical pressure exerted in the fluid filled inner lumen of the mating device to an electrical signal that is proportional to the pressure of the fluid in the inner lumen of the mating device; whereby, when the mating device is attached to the guidewire by placing the proximal end of the guidewire in the chamber, the fluid filled inner lumen of the mating device and the fluid filled inner lumen of the guidewire are fluidly connected so that there is a continuous fluid from the pressure transducer to the window on the guidewire so that pressure exerted at the window of the guidewire exerts a pressure on the pressure transducer that is proportional to the pressure exerted at the window; whereby the pressure transducer then converts the pressure measured at pressure transducer to an electrical signal that is proportional to the pressure exerted on the fluid at the window; a measurement instrument electrically connected to the pressure transducer wherein the measurement instrument reads the electrical signals generated by the pressure transducer that is proportional to the pressure exerted at the window of the guidewire and converts this electrical signal to a pressure reading corresponding to the pressure exerted at the window of the guidewire; and a display and wherein the measurement instrument conveys the pressure information to a user via the display; wherein the guidewire system is configured to correct the electrical signal produced by the pressure transducer for distortions and errors caused by the pressure signal traveling through the fluid filled lumens of the guidewire and the mating device by: creating an oscillating pressure signal with a known magnitude and known frequency at the distal window; measuring the pressure by the pressure transducer; comparing the pressure measured by the pressure transducer to the known magnitude of the pressure signal generated at the distal window by the oscillating pressure signal to create an offset magnitude for that frequency; repeating this process for all frequencies of interest; and applying the offset magnitude to the pressure measured by the guidewire in use for each frequency.