Purpose: One of the major limitations of thoracoscopic resection of lung nodules is localization of the target, especially when the lesion is deep or very small: we investigated the efficacy of US as a technique for intraoperative localization.
Material and methods: We examined 11 patients who underwent diagnostic and/or curative thoracoscopic resection of benign or malignant, primary or metastatic lung nodules. The study was preceded by a preliminary phase in which we examined with US 5 patients that underwent thoracotomy. A multifrequency laparoscopic US probe with a deflectable linear headpiece mounted on a portable Esaote-Hitachi Spazio US unit was used.
Results: The US exploration of the lung requires the complete collapse of the parenchyma and is therefore particularly difficult in patients with severe chronic obstructive pulmonary disease (COPD). In the patients examined during thoracotomy US showed all the lesions but one 7-mm nodule in an emphysematous patient in whom complete parenchyma collapse could not be achieved. Also in the patients examined during thoracoscopy US detected all the targets (13/13), even a 13-mm metastatic nodule which had been visualized preoperatively by PET only. The smallest lesion found was a 4-mm fibrosarcoma metastasis. The mean time to achieve adequate lung collapse was about 40 minutes from selective exclusion of the affected lung.
Discussion: Thoracoscopic US has been recently introduced for the intraoperative localization of pulmonary nodules. In our experience this technique is helpful in localizing the targets, assessing the extent of surgical resection and studying possible vascular involvement. Considering the easy execution, the low cost, the lack of contraindications and complications of the technique and its accuracy when performed under optimal technical conditions, we think there are enough reasons to investigate this approach further.
Conclusions: Intraoperative US proved to be a useful technique of easy execution, even though it is heavily operator-dependent and limited in patients with severe COPD.