A Clinical Study Of Intraoperative Ultrasonography For Lung Cancer Surgery

Objective: The purpose of this study is to primarily determine the value and analyse the influencing factors of infraoperative ultrasonography (IUS) for lung cancer surgery. Methods: This study was composed of three parts. In part I ,the IUS was used to observe the course and the length of normal pulmonary vessel, and the characters of sonogram of pulmonary vessel was analysed. In part II, according to the actual situation of operation, the accuracy of IUS in judging the relationship of tumor and pulmonary vessel was assessed quantitatively compared with that of CT. The capability of JUS in predicting the resectability of tumor and the surgical method was also assessed. In part III, the capacity of LUS in detecting the lymph nodes in mediastinum and hikun was compared with that of CT with the results of operation and pathologic examination as the criterion. The accuracy of 1US in determining lymph nodes metastasis by the characters of sonogram and the geometric measures was also appraised. Results: Part I :The capability of IUS in detecting pulmonary vessel and judging its course and length is determined. Operative sonogram shows a three-layer structure of the normal pulmonary vascular wall. The outer layer which represents a clearly bright stripe is hyperechoic. Part II :The accuracies of IUS and CT in judging the relationship of tumor and pulmonary vessel were 81.0% and 72.3% respectively (P0.037). The accuracy was affected by the location and size of tumoi; and the accuracy to the right lung cancer was higher than that to the left, and the accuracy was highest to those tumors 3 that their diameters ranged from 3 to 5 cm. The accuracy of IUS was high in predicting the resectability of tumor (83.6%), but low in predicting the surgical method (63.3%). Part Ill: The percentages of IUS and CT in detecting lymph nodes in mediastinum and hilum were 83.6% and 74.4% respectively (P=O.025). The result of IUS in detecting lymph nodes was influenced by their location and size. The detecting percentage was high in the lymph node groups 2R~ 4R~ 5 and low in groups 4L~ 1OL and 7, and the percentage was increased along with the increase of lymph node size. The accuracy of LUS in diagnosing lymph nodes metastasis by the characters of sonogram was higher than by the geometric measures (83.9%, 7 1.2% respectively), but there was no significant difference between the two methods (P=O.135). Conclusion: LUS is valuble for lung cancer surgery, particular in judging the relationship of central lung cancer and pulmonary vessel, predicting the resectability of tumor, preventing accidents during operation~ detecting the lymph nodes in mediastinum and hilum, and avoiding unnecessary tissue dissection.