An imaging system is provided comprising an imaging probe and at least one delivery device. The imaging probe comprises an elongate shaft, a rotatable optical core and an optical assembly. The elongate shaft comprises a proximal end, a distal portion, and a lumen extending between the proximal end and the distal portion. The rotatable optical core is positioned within the lumen of the elongate shaft and comprises a proximal end and a distal end. The rotatable optical core is configured to optically and mechanically connect with an interface unit. The optical assembly is positioned in the elongate shaft distal portion and proximate the rotatable optical core distal end. The optical assembly is configured to direct light to tissue and collect reflected light from the tissue. The imaging probe is constructed and arranged to collect image data from a patient site. The at least one delivery device is constructed and arranged to slidingly engage the imaging probe. Methods of introducing the imaging probe and the at least one delivery catheter into a patient are also provided.