In one embodiment a medical scan correction system includes a medical instrument having a distal end and an image sensor disposed at the distal end, and configured to be inserted into a body-part of a living subject, and a controller to register a medical scan of the body-part with a coordinate frame of the medical instrument, the medical scan including initial tissue-type indications, render a first image including a representation of the body-part and the initial tissue-type indications based on the medical scan, and a representation of the medical instrument, render a second image captured by the image sensor of a portion of the body-part, and responsively to a comparison between an appearance of a tissue in the second image of the portion of the body-part and an initial tissue-type indication of the tissue, update the medical scan to modify the tissue-type indication associated with the tissue.
