Research

We are developing a pseudo 3D visualization system by superimposing ultrasound images for endoscopic ultrasonography. The system consists of an ultrasonic endoscope and an electro-magnetic measurement sensor. The pseudo 3D volume is reconstructed by superimposing ultrasound images captured by the ultrasonic endoscope at arbitrary points, and displayed for surgeons by overlaying on endoscopic images in real-time.

3D model of gallbladder

4D Endoscope

Papers

• Yumi Iwashita, Shinji Tarumi, Ryo Kurazume, Makoto Hashizume, Development of Pseudo 3D Visualization System by Superimposing Ultrasound Images, International Symposium on Assistive and Recuperative Technologies for Injured, Ill, Pregnant, Elderly and people with Disabilities, Isai, Romania, July 24-26, 2009
• Shinji Tarumi, Yumi Iwashita, Ryo Kurazume, and Makoto Hashizume, Development of Pseudo 3D Visualization System for Endoscopic Ultrasonography, Proc. 5th Joint Workshop on Machine Perception and Robotics (MPR2009), MPR2009-ps2-5, (2009 10)

We are conducting joint researches with Medical School of Kyushu University and Osaka University. The research topics include the navigation system for endoscopic robotics surgery, 3D diagnosis system for hip replacement surgery, image guide for endotracheal intubation, etc. For instance, we propose a method to estimate a 3D shape of patient's femur from two radiographs and a parametric femoral model. Firstly, we develop the parametric femoral model utilizing statistical procedure of 3D femoral models taken by CT images of a number of patients. Then, the pose and patient-specific shape parameters of the parametric model are estimated from two 2D radiographs using a distance map constructed by the Level Set Method. Experiments using synthesized images, fluoroscopic images of a phantom femur, and in vivo images for hip prosthesis patients are successfully carried out, and it is verified that the proposed system has practical applications.

Radiograph

Shape estimation

Papers

• Ryo Kurazume, Kaori Nakamura, Toshiyuki Okada, Yoshinobu Sato, Nobuhiko Sugano, Tsuyoshi Koyama, Yumi Iwashita, Tsutomu Hasegawa, 3D reconstruction of a femoral shape using a parametric model and two 2D fluoroscopic images, Computer Vision and Image Understanding, Volume 113, Issue 2, pp. 202-211, (2009.2)
• Yumi Iwashita, Ryo Kurazume, Kaori Nakamura, Toshiyuki Okada, Yoshinobu Sato, Nobuhiko Sugano, Tsuyoshi Koyama , Tsutomu Hasegawa, Patient-specific femoral shape estimation using a parametric model and two 2D fluoroscopic images, ACCV'07 Workshop on Multi-dimensional and Multi-view Image Processing, MM-O-9, November 2007.
• Ryo Kurazume, Kaori Nakamura,Toshiyuki Okada, Yoshinobu Sato, Nobuhiko Sugano,Tsuyoshi Koyama, Yumi Iwashita, and Tsutomu Hasegawa, 3D reconstruction of a femoral shape using a parametric model and two 2D fluoroscopic images, in Proc. IEEE International Conference on Robotics and Automation, 2007.
• Yumi Iwashita, Shinji Tarumi, Ryo Kurazume, Makoto Hashizume, Development of Pseudo 3D Visualization System by Superimposing Ultrasound Images, International Symposium on Assistive and Recuperative Technologies for Injured, Ill, Pregnant, Elderly and people with Disabilities, Isai, Romania, July 24-26, 2009

Papers

• Ken'ichi Morooka, Xian Chen, Ryo Kurazume, Uchida Seiichi, Kenji Hara, Yumi Iwashita, Makoto Hashizume, Real-time Nonlinear FEM with Neural Network for Simulating Soft Organ Model Deformation, The 11th International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI 2008), New York, USA, Sep. 2008

We have proposed a new registration algorithm of 2D color images and 3D geometric models for the navigation system of surgical robot. A 2D-3D registration procedure is used to precisely superimpose a tumor model on an endoscopic image and is therefore indispensable for the surgical navigation system. Thus, the performance of the 2D-3D registration procedure influences directly the usability of the surgical robot operating system. One of the typical techniques that has been developed is the use of external markers. However, the accuracy of this method is reduced by the breathing or heartbeat of the patient, as well as other unknown factors. For precise registration of 3D models and 2D images without external markers or special measurement devices, a new registration method is proposed that utilizes the 2D images and their distance maps as created by the Fast Marching Method.

Papers

• Yumi Iwashita, Ryo Kurazume, Kozo Konishi, Masahiko Nakamoto, Naoki Aburaya, Yoshinobu Sato, Makoto Hashizume and Tsutomu Hasegawa, Fast Model-Image Registration using 2D Distance Map for Surgical Navigation System, Advanced Robotics, Vol.21, No.7, pp751-770, (2007.4)
• Yumi Iwashita, Ryo Kurazume, Kozo Konishi, Masahiko Nakamoto, Makoto Hashizume, and Tsutomu Hasegawa, Fast 2D-3D Registration for Navigation System of Surgical Robot, in Proc. IEEE International Conference on Robotics and Automation, pp.909-915, 2005.
• Yumi Iwashita, Ryo Kurazume, Kenji Hara, and Tsutomu Hasegawa, Fast Alignment of 3D Geometrical Models and 2D Color Images using 2D Distance Maps, in Proc. The 5th International Conference on 3-D Digital Imaging and Modeling, 2005.