An interventional device, e.g. an intravascular catheter such as IVUS or OCT, by using an optical shape sensor (OSS)-based mechanism at the time of the intravascular image acquisition. An OSS fiber with a predetermined shape is merged with the intravascular catheter and the predetermined shape of OSS fiber has OSS identifiable features positioned to allow optical determination of orientation (rotational angle relative to a longitudinal axis of the catheter) at the longitudinal position of the catheter where the imaging sensor resides. The predetermined shape of the OSS-device indicates an angle of rotation of a predetermined reference orientation of the catheter relative to an OSS sensor during navigation/pullback of the intravascular catheter through a vessel. Alternatively, or additionally, a multi-core OSS cable can be used, which allows calculation of twist angle between two nodes of the OSS cable, and thus a measure of rotational angle. With such a system, it is possible to get rotational angle (orientation) information gathered for each intravascular image. Such orientation information can be used to visualize one single image with correct angular alignment. Further, by calibrating individual images of a pull-back sequence with respect to the gathered rotational angle and position information, it is possible to orient the cross- sectional intravascular data on an X-ray image with improved accuracy that may have better diagnostic value.Linvention concerne un dispositif dintervention, par exemple un cathéter intravasculaire tel que IVUS ou OCT, utilisant un mécanisme basé sur un capteur de forme optique (OSS) au moment de lacquisition dimage intravasculaire. Une fibre OSS ayant une forme prédéterminée est fusionnée au cathéter intravasculaire, et la forme prédéterminée de la fibre OSS présente des caractéristiques identifiables OSS pour permettre une détermination optique dorientation (angle de rotation par rapport à un axe longitudinal du cathéter) dans la posi
