A Method for Fluoroscopy Based Navigation System to Assist Needle Insertion Concerning Reduced Radiation Exposure for Endoscopic Disc Surgery

Abstract

Endoscopic disc surgery requires a process of inserting a guide-needle to the target lumbar disc. And the insertion path is manually planned by drawing lines on the patient’s skin while monitoring the fluoroscopic view of the lumbar. Such operative procedure inevitably exposes both surgeon and patient to the fluoroscopic radiation emitted from c-arm for a long time. To reduce the radiation exposure time, this study proposes a computer assisted operative planning method implemented by using computer vision and computer graphics theory. This method calculates the 3-dimensional path line of guide-needle from multiple triangular planes. Triangular planes can be obtained by analyzing 2-dimensional images of patient’s disc in 3 different angles from rotationally movable c-arm. Additionally, a method of guiding robot’s control based on the 3-dimensional needle path was developed by implementing the Hand-eye (end-effector and camera) calibration. Hand-eye calibration method calculates the geometric transformation matrix between the c-arm coordinate system and base of guidance robot coordinate system. The proposed system was then tested for its accuracy.