2005 年 6 巻 4 号 p. 483-489
In neurosurgery such as the treatment of glioma, it is very important to remove tumor as accurately as possible at the boundary between tumor and normal tissue in order to prevent the recurrence. To achieve this, we had proposed a robotic laser scanning system using a micro laser with wave length of 2.8 um. This micro laser is suitable to remove the tumor at the brain surface because of its strong absorption feature by water. It is necessary, however, to keep the distance between the laser probe and the target at its focal length. In this research, we developed an automatic-focusing system using a guide laser and a CCD camera. In addition, we performed some experiments for evaluation in vivo and an in vivo test with the laser ablation on a porcine brain. Results showed that accuracy of focusing largely depends on the condition of the brain surface. In the near future, we will improve our method so that it will not be affected by the condition of the brain surface.