Yukikuni Komine

Fiber Optic Pulsed Photothermal Radiometry For Urinary Stone Diagnosis

We investigated a fiber-optic infrared radiation diagnosis for in vivo urinary tract tissue discrimination during laser urinary stone fragmentation. Such in vivo analysis may be useful for preventing mis-irradiation to surrounding tissue. Since we plan to use infrared lasers and infrared fibers to the urinary stones photofragmentation, the pulsed photothermal radiometry(PPTR) was employed in this study due to its simplicity and benefit of common use of the infrared laser and fiber to therapy and diagnosis. We successfully demonstrated a discrimination between urinary stones and urinary tract tissue, by a chalcogenide glass fiber-optic CO laser induced PPTR analysis.

Discrimination between urinary tract tissue and urinary stones by fiber-optic-pulsed photothermal radiometry method in vivo

To minimize urotherial tissue injuries by false laser irradiation during the laser stones fragmentation, a novel fiber-optic analytical system was developed which was able to distinguish urotherial tissues from urinary stones in vivo. This system was composed of the fiber-optic pulsed photo-thermal radiometry (PPTR) system together with a thin-fiber endoscope. The ultraviolet Ar laser was employed as the excitation light source. The catheter of this system was 6F in diameter and consisted of SiO2 glass fiber (400 micrometers (phi) ) as an excitation line, an As-S glass fiber (400 micrometers (phi) ) as a detection line, and a thin-fiber endoscope (610 micrometers (phi) ). A urinary stone was introduced into the canine ureter uneter under general anesthesia. The catheter system was inserted through an opening of the ureter distal to the stone. The e-folding decay time of the PPTR waveform of which optical and/or thermal properties of the tissues and stones were characterized was measured in vivo. The e-folding decay times were significantly different between urinary stones and the canine ureter. These results suggest that the fiber-optic PPTR analysis might be significantly useful procedure to prevent urotherial tissue from false irradiation injuries in clinical laser stone fragmentation.

Novel fiber optic pulsed photo-thermal radiometry for transluminal tissue characterization

The use of fiber-optic pulsed photo-thermal radiometry for noncontact diagnostic tissue characterization under transluminal catheterization is described. The method uses a simple time-dependent radiation waveform measurement and shape analysis. It has been applied to urinary tissue characterization and artery disease diagnosis.<<ETX>>