1. Computer-implemented segmentation and quantification method using an intravascular optical coherence tomography (OCT) system having an OCT signal emitting and receiving instrument comprising: obtaining an OCT image set comprising one or more images of a portion of a blood vessel; segmenting a lumen portion of at least one of the one or more images; segmenting an OCT signal emitting and receiving instrument portion of the at least one of the one or more images; segmenting a vessel wall portion of the at least one of the one or more images; and, segmenting a calcified plaque portion of the at least one of the one or more images.