Carbon dioxide insufflation and thoracoscopic ultrasonography image of pure ground-glass nodule.

Thoracic surgeons frequently encounter early lung cancer showing a pure ground-glass nodule. Although thoracoscopic wedge resection is used extensively, it cannot be easily located for surgical procedures. Thoracoscopic ultrasonography is a real-time and less invasive technique for small lung lesion localization during thoracoscopic surgery. However, this technique has not been widely adopted because residual air in the lung results in poor ultrasound images. A 64-year-old woman was found to have pure ground-glass nodule. For intraoperative localization, we performed thoracoscopic ultrasonography. To deflate the lung, we insufflated carbon dioxide into the thoracic cavity and maintained an intrathoracic pressure of 10 mmHg for 5 min. We easily achieved complete lung collapse without any complications; pure ground-glass nodule clearly showed as a hyperechoic lesion. We performed thoracoscopic wedge resection with a pathological diagnosis of adenocarcinoma in situ. Carbon dioxide insufflation into the thoracic cavity may be effective for complete lung deflation, which is useful to detect small lung nodules.