A study and analysis of using ND:YAG laser in hemorrhage control

number: 
2389
إنجليزية
Degree: 
Author: 
Rawaa Abdel-Redda Kathem
Supervisor: 
Dr. Munqith Saleem
Dr. Anam Rasheed Al-Salihi
year: 
2009

Abstract: This study tries to reach an approach for hemorrhage control process based on using Nd:YAG laser, in order to reduce the time needed for coagulation. The Nd:YAG laser with its different powers and modes is one of the most widely used lasers in medical applications . The research shows that this laser type is a powerful and useful method for haemostaisis, one of the most important medical applications of laser with no mentioned side effects. The work in this study describes the improvement of haemostaisis time by using Nd:YAG laser. The normal haemostaisis process, types of hemorrhage, methods of controlling hemorrhage, the laser system used, and the principles of laser tissue interaction are described in the present work. The treatment with Nd:YAG laser system is based on the thermal effect resulting from the Nd:YAG laser beam that is focused on the location of incision that was made in the ear of the rabbit. Then the coagulation time was counted immediately for a group that was not treated with laser and the groups treated with lasers of different modes and energies. Continuous beam and pulsed beam of Nd:YAG laser with wavelength of 1064nm and with power of 100mW for the continuous and energies of 20, 80, and 100mJ for pulsed and a wavelength is used. A bioheat transfer pattern is proposed to study thermal distribution in biological tissues caused by laser radiation. This mathematical model is applied by using finite difference equation on MATLAB. From the results we found that continuous Nd:YAG laser has more effect than the natural coagulation, and the pulsed Nd:YAG laser has more effect than continuous regarding the enhancing the process of haemostaisis. This indicates that continuous laser beam group needed more time for haemostaisis due to its low power. From the results we also found that the 60ーC represents the minimal distribution of coagulated tissue immediately after continuous (CW) Nd:YAG laser irradiation, and the time needed to reach coagulation ranges from (60_100) seconds, and the mean time needed for coagulation practically is 79.57 seconds.