Devices, systems, and methods of imaging a blood vessel are provided. For example, the method can include obtaining fluoroscopic image data of a region of interest in a blood vessel using an x-ray source； obtaining intravascular ultrasound (IVUS) data at a plurality of positions across the region of interest using an IVUS component disposed on an intravascular device； processing the fluoroscopic image data and IVUS data, including: determining, using the fluoroscopic image data, a position of the intravascular device with respect to the x-ray source at each of the plurality of positions across the region of interest； co-registering the fluoroscopic image data and the IVUS image data； and generating, a model of the region of interest including position information of a border of a lumen of the blood vessel at each of the plurality of locations； and outputting a visual representation of the model of the region of interest.
