title: A novel method for texture-mapping conoscopic surfaces for minimally invasive image-guided kidney surgery.
abstract: OBJECTIVE
  Organ-level registration is critical to image-guided therapy in soft tissue. This is especially important in organs such as the kidney which can freely move. We have developed a method for registration that combines three-dimensional locations from a holographic conoscope with an endoscopically obtained textured surface. By combining these data sources clear decisions as to the tissue from which the points arise can be made.
  
  
  METHODS
  By localizing the conoscope's laser dot in the endoscopic space, we register the textured surface to the cloud of conoscopic points. This allows the cloud of points to be filtered for only those arising from the kidney surface. Once a valid cloud is obtained we can use standard surface registration techniques to perform the image-space to physical-space registration. Since our methods use two distinct data sources we test for spatial accuracy and characterize temporal effects in phantoms, ex vivo porcine and human kidneys. In addition we use an industrial robot to provide controlled motion and positioning for characterizing temporal effects.
  
  
  RESULTS
  Our initial surface acquisitions are hand-held. This means that we take approximately 55 s to acquire a surface. At that rate we see no temporal effects due to acquisition synchronization or probe speed. Our surface registrations were able to find applied targets with submillimeter target registration errors.
  
  
  CONCLUSIONS
  The results showed that the textured surfaces could be reconstructed with submillimetric mean registration errors. While this paper focuses on kidney applications, this method could be applied to any anatomical structures where a line of sight can be created via open or minimally invasive surgical techniques.
authors.affiliation: Medtronic Surgical Technologies, Louisville, CO, 80027, USA.
authors.forename: Rowena
authors.initials: R
authors.lastname: Ong
authors.affiliation: Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
authors.forename: Courtenay L
authors.initials: CL
authors.lastname: Glisson
authors.affiliation: Hannover Center of Mechatronics, Leibniz Universität Hanover, Hanover, Germany.
authors.forename: Jessica
authors.initials: J
authors.lastname: Burgner-Kahrs
authors.affiliation: Memorial Sloan Cancer Center, New York City, NY, USA.
authors.forename: Amber
authors.initials: A
authors.lastname: Simpson
authors.affiliation: MAKO Surgical, Ft. Lauderdale, FL, USA.
authors.forename: Andrei
authors.initials: A
authors.lastname: Danilchenko
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
authors.forename: Ray
authors.initials: R
authors.lastname: Lathrop
authors.affiliation: Department of Urologic Surgery, Vanderbilt Medical Center, Nashville, TN, 37235, USA.
authors.forename: S Duke
authors.initials: SD
authors.lastname: Herrell
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Webster
authors.affiliation: Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Miga
authors.affiliation: Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA. bob.galloway@vanderbilt.edu.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Galloway
mesh_terms: D000818:Animals; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000601:surgery*; D007834:Lasers; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D019047:Phantoms, Imaging; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013552:Swine
keywords: Conoscopy; Image-guided surgery; Kidney surgery; Minimally invasive surgery