METHOD AND SYSTEM FOR USING TOOL WIDTH DATA TO ESTIMATE MEASUREMENTS IN A SURGICAL SITE
A system and method apply computer vision to images captured of a surgical site in order to measure the distance between surgical instruments at the surgical site. Images of the site are captured and analyzed to estimate a width in pixels of a first surgical instrument positioned at the treatment site. The depth coordinate Z of the tip of the first surgical instrument is determined by comparing the estimated tool width to the known physical width of the first surgical instrument, and the corresponding X and Y coordinates are estimated based on the Z coordinate. The coordinates of the tip of a second instrument are determined in the same manner, and the distance between the tips is then calculated, and the distance value is displayed as an overlay on the image display.
1 . A system, comprising:
a camera positionable to capture image data corresponding to a treatment site;
at least one processor and at least one memory, the at least one memory storing instructions executable by said at least one processor to:
analyze image data to estimate a width in pixels of a first surgical instrument positioned at the treatment site;
estimate a depth coordinate Z of a tip of the first surgical instrument by comparing the estimated tool width to the known physical width of the first surgical instrument.
2 . The system according to claim 1 , wherein the instructions are further executable by said at least one processor to estimate X and Y coordinates of the first surgical instrument tip based on the Z coordinate.
3 . The system according to claim 2 , wherein the instructions are further executable by said at least one processor to:
analyze image data to estimate a width in pixels of a second surgical instrument positioned at the treatment site;
estimate a depth coordinate Z of a tip of the second surgical instrument by comparing the estimated second surgical instrument tool width to the known physical width of the second surgical instrument; and
estimate X and Y coordinates of the second surgical instrument tip based on the estimated Z coordinate of the second surgical instrument tip, and
estimate a distance between the first surgical instrument tip and the second instrument tip using the estimated X, Y and Z coordinates for the first instrument tip and the second instrument tip.
4 . The system of claim 1 , wherein the camera is a monocular camera.
5 . The system of claim 1 , wherein the camera is a stereoscopic camera.
6 . The system of claim 1 , wherein the only known intrinsic parameter of the camera is the f parameter.
7 . A method comprising:
capturing image data of a treatment site using a camera positioned in a body cavity;
analyzing the image data to estimate a width in pixels of a first surgical instrument positioned at the treatment site;
estimating a depth coordinate Z of a tip of the first surgical instrument by comparing the estimated tool width to the known physical width of the first surgical instrument.
8 . The method of claim 8 , further comprising estimating X and Y coordinates of the first surgical instrument tip based on the Z coordinate.
9 . The method according to claim 8 , further including:
analyzing the image data to estimate a width in pixels of a second surgical instrument positioned at the treatment site;
estimating a depth coordinate Z of a tip of the second surgical instrument by comparing the estimated second surgical instrument tool width to the known physical width of the second surgical instrument;
estimating X and Y coordinates of the second surgical instrument tip based on the estimated Z coordinate of the second surgical instrument tip, and
estimating a distance between the first surgical instrument tip and the second instrument tip using the estimated X, Y and Z coordinates for the first instrument tip and the second instrument tip.
10 . The method according to claim 9 , further including displaying images from the camera on an image display, and displaying an overlay on the image display showing the distance estimated.
11 . The method according to claim 10 , further including displaying an overlay on the image identifying points between which the distance is measured.