Laparoscopic infrared imaging.
BACKGROUND
As an adjunct to direct visual imaging, an infrared endoscope was developed to assist in the identification of various anatomic structures and to assess tissue viability during laparoscopic procedures. A camera sensitive to emitted energy in the mid-infrared range (3 to 5 microm) was incorporated into a two-channel visible-light laparoscope.


METHODS
Laparoscopic procedures were performed in a porcine model, inexperienced laparoscopists being asked to localize and differentiate structures before dissection using the visible-light system and then the infrared system. To determine clinical utility, nine laparoscopic urologic procedures were performed with the assistance of the infrared system.


RESULTS
In the clinical evaluation, infrared imaging proved to be useful in differentiating between blood vessels and other anatomic structures. In contrast to the experience with the conventional endoscope, vessel identification, assessment of organ perfusion, and transperitoneal localization of the ureter was successful in all instances using the infrared system. In the porcine model, this system also permitted assessment of bowel perfusion during laparoscopic occlusion of mesenteric vessels and distinguished between the cystic duct and artery.


CONCLUSIONS
Infrared imaging is a potentially powerful adjunct to laparoscopic surgery. It may improve the differentiation and localization of anatomic structures and allow assessment of physiologic features, such as perfusion, not previously attainable with laparoscopic techniques.
Cadeddu
J A
JA
Department of Urology, The University of Texas Southwestern Medical Center, Dallas, USA.
Jackman
S V
SV
Schulam
P G
PG
D000818:Animals; D003950:Diagnostic Techniques, Urological; D006801:Humans; D007259:Infrared Rays; D020706:Laparoscopes; D010535:Laparoscopy / Q000379:methods*; D023421:Models, Animal; D013552:Swine; D013817:Thermography / Q000295:instrumentation / Q000379:methods