Surgical procedures using instrument to boundary spacing information extracted from real-time diagnostic scan data

Abstract

Specific embodiments of the invention are directed to improved surgical procedures involving the use of processed non-visual three-dimensional data (i.e. diagnostic scan data) to provide a surgeon with additional guidance (i.e. more than that generally obtained from visual observation of the working area) concerning the distance separating a working end of a surgical instrument and the posterior portion of a target tissue. Separation information may be used to aid the surgeon in minimizing the risk of unintended penetration of adjacent tissue with the working end of the instrument. Some embodiments provide for the visual and/or auditory conveyance of distance information to the surgeon. Additional embodiments provide for overlaying visual representations of selected three-dimensional structure information (e.g. depths of troughs cut into the lens) with the real surface feature images viewed by the surgeon.

We claim: 
     
         1 . A method for an improved phacoemulsification procedure, comprising:
 providing a phacoemulsification instrument including a distal working end configured to be inserted through an opening in the anterior region of an eye's lens capsule;   processing diagnostic scan data for at least a portion of the lens capsule and the working end of the phacoemulsification instrument;   providing a signal corresponding to a calculated separation distance information from an analysis of the diagnostic scan data and the distal working end of the phacoemulsification instrument during the course of the phacoemulsification procedure, wherein during the course of the phacoemulsification procedure, the diagnostic scan data is undated to provide the calculated separation signal in real time.   
     
     
         2 . The method of  claim 1 , wherein the portion of the capsule from which at least some of the diagnostic scan data is obtained has a relatively planar central region which defines an XY plane from which a Z-axis extends toward the anterior portions of the eye, and wherein the separation distance is measured as a distance between the working end and the capsule along a line that is substantially parallel to the Z-axis. 
     
     
         3 . The method of  claim 2 , additionally comprising:
 analyzing the diagnostic scan data to provide thickness information between an anterior surface of the lens capsule and the portion of the capsule along lines substantially parallel to Z-axis for a plurality of XY locations.   
     
     
         4 . The method of  claim 3 , wherein the thickness information is provided as a visual representation overlaid with the visual image being viewed. 
     
     
         5 . The method of  claim 1 , additionally comprising:
 overlaying a visual representation of selected diagnostic scan information with visual images being viewed by the surgeon.   
     
     
         6 . The method of  claim 5 , additionally comprising:
 updating the overlayed visual representation a plurality of times per second.   
     
     
         7 . The method of  claim 6 , wherein the updating is done at a rate of about at least 20 times per second. 
     
     
         8 . The method of  claim 5 , wherein the overlaying is updated with each update of captured visual image data that is displayed to the surgeon. 
     
     
         9 . The method of  claim 5 , additionally comprising:
 aligning the overlaid visual representation and a visual image with one another using markerless tracking methods.   
     
     
         10 . The method of  claim 1 , wherein the diagnostic scan data comprises one or more of data from an OCT, an MRI, an UBM, and an ultrasound. 
     
     
         11 . The method of  claim 1 , wherein the separation distance information is an auditory signal comprising one or more of: a series of discrete pulse-like signals that can vary in temporal duration based on a predetermined set of distance ranges, a series of discrete pulse-like signals that can vary in temporal separation based on a predetermined set of distance ranges, a signal whose pitch varies in frequency based on a predetermined set of distance ranges, and a signal that enunciates different sounds, selected from the group consisting of numbers, letters, words, or phrases based on a predetermined set of distance ranges. 
     
     
         12 . A medical procedure for penetrating, or removing target tissue, to a desired thickness from a posterior or distal boundary of the target tissue without penetrating the boundary with a working end of a surgical instrument, the procedure comprising:
 forming at least one opening in a covering tissue in proximity to the anterior surface of the target tissue to provide access to said anterior surface of the target tissue;   inserting a working end of surgical instrument through the opening in the cover tissue to contact the target tissue;   obtaining diagnostic scan data for the target tissue, the posterior boundary, and the working end of the surgical instrument;   analyzing the diagnostic scan data to obtain a separation distance between the working end of the surgical instrument and the posterior boundary region; and   operating the surgical instrument while viewing the target tissue, the working end of the surgical instrument and while receiving separation distance information from the analysis of the diagnostic scan data, wherein during the course of the procedure, the diagnostic scan data, the analysis of the data, and the receiving of the separation distance information are updated a plurality of times.   
     
     
         13 . The procedure of  claim 12 , wherein the target tissue from which at least some of the diagnostic scan data is obtained has a relatively planar central region which defines an XY plane from which a Z-axis extends toward the anterior surface, and wherein the separation distance is measured as a distance between the working end and the target tissue along a line that is substantially parallel to the Z-axis. 
     
     
         14 . The procedure of  claim 13 , additionally comprising:
 analyzing foe diagnostic scan data to provide thickness information between the anterior surface of the target tissue and the posterior boundary along lines substantially parallel to Z-axis for a plurality of XY locations.   
     
     
         15 . The procedure of  claim 12 , wherein the thickness information is provided as a visual representation overlaid with the visual image being viewed by a surgeon. 
     
     
         16 . The procedure of  claim 12 , additionally comprising:
 overlaying a visual representation of selected diagnostic scan information with visual images being viewed by a surgeon.   
     
     
         17 . The procedure of  claim 16 , additionally comprising:
 aligning the overlaid visual representation and a visual image with one another using markerless tracking methods.   
     
     
         18 . The procedure of  claim 12 , wherein the diagnostic scan data comprises one or more of data from an OCT, an MRI an UBM, and an ultrasound. 
     
     
         19 . The procedure of  claim 12 , wherein surgical instrument comprises an instrument selected from the group consisting of (1) a needle, (2) a probe, (3) forceps, (4) a clamp, (5) scissors, (6) a knife, (7) a spreader, (8) a retractor, (9) tweezers, (10) an delivery cannula, (11) an aspirating cannula, (12) a cystotome, (13) a hydrodissector, (14) a hook, (15) a phaco chopper (16) a polisher, (17) a scrapper, (18) a tissue extraction tool, and (19) a deposition tool. 
     
     
         20 . The procedure of  claim 12 , wherein the removed tissue includes one or more of a tumor, a crystalized lens, and a path blockage.