A drive assembly for driving an imaging catheter has a rotatable fiber and a rotatable drive shaft. The drive assembly includes a fiber optic rotating junction and a motor configured to rotate the rotatable portion of the fiber optic rotating junction. In some embodiments, the drive assembly includes a sensor configured to detect a rotational position of the fiber optic rotating junction and a processor configured to obtain the detected rotational position and stop the motor only when the fiber optic rotating junction is in a predetermined rotational position. In some embodiments, the motor includes a hollow shaft through which at least a portion of the fiber optic rotating junction extends.