Use of India Ink During Preoperative Computed Tomography Localization of Small Peripheral Undiagnosed Pulmonary Nodules for Thoracoscopic Resection

Background Computed tomography (CT) scans of the chest permit us to identify a large number of small peripheral, undefined pulmonary lesions that require a diagnosis. Broncoscopy results are generally negative in these cases, and needle aspiration results are often inconclusive owing to poor cytology and false-negative cases. Thoracoscopy is an ideal tool but allows us only to localize lesions that retract the visceral pleura. Our aim in this study was to establish a marking procedure for excising nodules of unknown etiology by injecting India ink on the surface of the lung. Methods Since January 2008, eight patients (six men, two women) who had been diagnosed as having a peripheral small pulmonary nodule of unknown etiology were selected for preoperative tattooing under CT guidance to facilitate thoracoscopic wedge resection. Results In six cases, thoracoscopy allowed diagnosis and definitive treatment of two benign peripheral nodules and four single metastases from colon carcinoma. In two patients who had been diagnosed to have a primitive non-small-cell lung cancer on frozen section following thoracoscopy, the surgical treatment was concluded with limited lateral thoracotomy and lobectomy with ilomediastinal node dissection. Conclusions Our experience suggests that this CT technique, which includes using India ink to label and localize peripheral small pulmonary nodules, is a safe, valid option for marking the lung, thereby facilitating subsequent thoracoscopic resection.