Workspace determination and robot design of a prototyped surgical robotic system based on a cadaveric study in Endonasal transsphenoidal surgery

The Endonasal endoscopic transsphenoidal surgical system will be presented in this study. The Endonasal transsphenoidal surgery (ETSS), a process to approach and remove pituitary tumor, is less invasive, and causes less pain and faster recovery than the old process (Craniotomy surgery). However, the optic nerves, cavernous sinuses and carotid arteries are intimately next to the pituitary gland. A slight deviation of tools from ETSS-pathway can lead to serious complications. Therefore, neurosurgeons should control their hands steadily and also concentrate on the operation at the same time. This study proposes to design and develop assisting robot for ETSS. This study is separated into 2 parts: the first is ETSS-workspace analysis and the second is robot design and implementation for surgical assisting. For the ETSS-workspace, optical tracking system is used to detects motion of surgical instruments while ETSS-procedure is performed in cadaveric case. Then, the workspace and range of motion of instruments are analyzed. For robot designing, the workspace of surgical tools was used to be constrain of robot´s workspace. The robot consists of 6 DOF; 3 DOF for translation movements, 2 DOF for rotation movements and 1 DOF for tool insertion. DELTA parallel robot is applied for 3 DOF in translation movements. Precision and accuracy of this robot are evaluated by ETSS-phantom that known the position, orientation of a pituitary tumor and ETSS-pathway. This robot is a part of ETSS system to assist neurosurgeons to hold and control medical instruments in the operation. Furthermore, this system is able to be developed by applying with medical image; CT-SCAN and MRI to analyze optimal pathway of medical tools.