Integration delayed optical feedback in image guidance

A method comprising the steps of:

• determining a sequence of images of an interior of a body at respective times that correspond with a timestamp Tf;
• determining a sequence of sensor positions (xc, yc) of an instrument in the respective images of the interior of the body at the respective times that correspond with the timestamp Tf;
• determining, at a time that corresponds with a timestamp Ts, a tissue parameter at a sensor position of the instrument, wherein the instrument comprises a sensor for optical inspection of tissue in the body, the instrument being configured to generate a tissue signal, wherein an interval between neighboring Tf timestamps is smaller than an interval between neighboring Ts timestamps;
• determining, for each time that corresponds with a timestamp Ts, an indication of tissue-type at a spatial position (xs, ys) of the sensor for a corresponding timestamp Ts;
• and
• displaying, via a display unit, an image that comprises a combination of (i) an image of the interior of the body at a corresponding timestamp Tf and (ii) a representation of tissue parameter at a previous sensor position at a time corresponding with a timestamp Ts.

A computer program product comprising instructions which when executed on a digital processor, cause a computer to perform a method comprising the steps of determining a sequence of images of an interior of a body at respective times that correspond with a timestamp Tf,

• determining a temporal sequence of sensor positions of an instrument in the respective images of the interior of the body at the respective times that correspond with the timestamp Tf,
• determining, at a time that corresponds with a timestamp Ts, a tissue parameter at a sensor position of the instrument, wherein the instrument comprises a sensor for optical inspection of tissue in the body, the instrument being configured to generate a tissue signal, wherein an interval between neighboring Tf timestamps is smaller than an interval between neighboring Ts timestamps,
• determining, for each time that corresponds with a timestamp Ts, an estimated sensor position based on a part of the temporal sequence of sensor positions for a time period around a time that corresponds with a corresponding timestamp Ts, and
• displaying on a display unit an image that comprises a combination of an image of the interior of the body at a corresponding timestamp Tf and (ii) a representation of tissue parameter at a previous sensor position at a time corresponding with a timestamp Ts.

An instrument for use in a system for guiding the instrument in a body,

• the instrument comprising an optical probe, and
• the system for guiding the instrument comprising:
• a tissue-type determination device configured to receiving a tissue signal from the instrument at times that correspond with a timestamp Ts, the tissue-type determination device configured to determine a set of parameters indicative of tissue type based on the tissue signal received from the instrument,
• a medical imaging device configured for forming an image of an interior of the body, the medical imaging device recording a temporal sequence of images, wherein each image is separated from a neighboring image in the temporal sequence by a temporal distance that corresponds with a timestamp Tf, wherein an interval between neighboring Tf timestamps is smaller than an interval between neighboring Ts timestamps,
• an image processing unit time-synchronized with the tissue-type determination device and the image processing unit, wherein the image processing unit is configured to establish a combined image of the interior of the body at each timestamp Tf that comprises (i) a current instrument position (xc, yc) and (ii) an indication of tissue-type at a previous spatial position of the instrument (xs, ys) that corresponds with a tissue signal retrieval location for a timestamp Ts so that the combined image of the interior of the body comprises both the current instrument position and the indication of tissue-type at the previous spatial position of the instrument that corresponds with the tissue signal retrieval location for the corresponding timestamp Ts, and
• a display unit for displaying the combined image of the interior of the body.