A new contact probe for intraoperative laser ablation.

Several clinical factors decrease the accuracy of intraoperative laser ablation. The distance to the target, the irradiation angle, and the media are reported among these factors. We developed a new laser probe to resolve these problems. This probe has a hollow conical tube with a tip covered by a thin film. Zero-degree centigrade saline was fed into this probe. Results from using the new probe were compared with those from the conventional noncontact irradiation method with cooling by sprinkled cooling water. In beating canine hearts, ventricles were irradiated with neodymium:yttrium aluminum garnet (Nd:YAG) lasers at 50-200 J/mm2. There was no difference in the mean volume of irradiated tissue between the new and the noncontact method. However, the distribution of volume values in the new method was smaller than that in the noncontact method (P < 0.05). In conclusion, results obtained indicate that this new probe could perform more accurate intraoperative ablation than the conventional method. Problems of stabilizing the distance to the target, the irradiation angle, and the media were resolved.