A novel and simple method for identifying the lung intersegmental plane using thermography

Identifying the intersegmental plane is very important for successful lung segmentectomy. Although several methods are available, they require specialized skills and pose a potential risk of losing sight of the correct intersegmental planes. Therefore, easier and more reliable methods are required. In this study, we hypothesized that surface temperatures of resecting segments or lobes decrease because of blood flow suppression after the ligation of target arteries and veins, and intersegmental planes can be visualized using a thermography. To test this hypothesis, we performed six lung resections (two lobectomies and four segmentectomies) on three pigs and, using a handheld thermography, we monitored the lung surface temperatures to identify intersegmental planes. We demonstrated that thermal imaging sharply demarcated intersegmental planes soon after the ligation of vessels in all procedures. Compared with other methods, thermography requires no special technical skills, drug injection and lung inflation. Therefore, we believe that the thermographic method described in this study will be a powerful option to identify intersegmental planes during anatomical lung segmentectomy.