Determination of uterine activity during labor by means of infrared thermography

Real-time infrared thermography for ureter detection during hysterectomy

BACKGROUND

Recognition of different anatomic structures might be difficult in the presence of diseases such as neoplasm or endometriosis that can subvert the anatomy. This can be a challenge for young surgeons approaching gynecologic surgery. The aim of the present study was to evaluate the effectiveness of infrared thermocamera to identify the anatomic structures in gynecologic surgery.

MATERIALS AND METHODS

From February 2010 to May 2011, consecutive patients who required abdominal hysterectomy were considered for eligibility. During a procedure for benign disease, we evaluated the temperature difference between the ureter and infundibulopelvic vessel (experiment A). In patients with gynecologic cancer, the thermal gradient was determined between the iliac vessels and the ureter (experiment B).

RESULTS

The data from 21 patients were recorded, 12 for experiment A and 9 for experiment B. We found a statistically significant difference between the ureter and vessels in both experiments (31.675°C ± 0.673°C for the ureter and 33.332°C ± 0.828°C for the infundibulopelvic vessel, P < 0.0001; 31.706°C ± 0.751°C for the ureter, 33.787°C ± 0.63°C for the iliac vein, and 33.784°C ± 0.639°C for the iliac artery, P < 0.0001).

CONCLUSIONS

Infrared imaging allowed us to identify the anatomic structures in laparotomy, providing preliminary data for its application in laparoscopy.

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 AND MATERIALS

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.

CONCLUSION

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.