In a method and apparatus for optically-based acquisition of slice images from a vessel of a subject, and for combining the slice images to provide an intuitively recognizable visualization of a pathology in the vessel, slice images of the vessel are acquired during pullback of an optical probe of the optically-based slice imaging system, while simultaneously acquiring an ECG signal from the subject. The slice images and the ECG signal are registered, and slice images acquired at a selected cardiac phase are combined into a scene. The slice images in the scene are subjected to a first data transformation to shift the vessel midpoint in each slice image to the image center of each slice image. After the first data transformation, the slice images in the scene are subjected to a second data transformation to produce the visualization. The second transformation, for example, can be a curved planar reformation to allow the vessel to be shown in longitudinal section.