Systems and methods for minimally-invasive optical-acoustic imaging

摘要

An imaging guidewire can include one or more optical fibers communicating light along the guidewire. At or near its distal end, one or more blazed or other fiber Bragg gratings (FBGs) directs light to a photoacoustic transducer material that provides ultrasonic imaging energy. Returned ultrasound is sensed by an FBG sensor. A responsive signal is optically communicated to the proximal end of the guidewire, and processed to develop a 2D or 3D image. In one example, the guidewire outer diameter is small enough such that an intravascular catheter can be passed over the guidewire. Techniques for improving ultrasound reception include using a high compliance material, resonating the ultrasound sensing transducer, using an attenuation-reducing coating and/or thickness, and/or using optical wavelength discrimination. Techniques for improving the ultrasound generating transducer include using a blazed FBG, designing the photoacoustic material thickness to enhance optical absorption. Techniques for distinguishing plaque or vulnerable plaque may be used to enhance the displayed image.

主权项

1. An imaging apparatus comprising:
an imaging guidewire including:
a first optical fiber including a first blazed fiber Bragg grating (FBG); an optical coupler defining a receptacle configured to receive the imaging guidewire, the optical coupler including:
a second optical fiber including a second blazed FBG, wherein when the imaging guidewire is positioned within the receptacle, the first blazed FBG is located substantially adjacent the second blazed FBG, and wherein the second blazed FBG is configured to couple light into or out of the first blazed FBG.