USE OF INTRATHORACIC ULTRASONOGRAPHY IN THE THORACOSCOPIC LOCALIZATION AND RESECTION OF PULMONARY TUMORS

The lung has not been suitable for ultrasonic investigation, because of the presence of air. Since we achieved good in vitro results on atelectatic pulmonary tissue, we have applied ultrasonography for the localization of intra-pulmonary tumours in video-assisted thoracoscopic resections. Four different probes were tested. In nine out of 10 cases peripherally and centrally located tumours could be identified and thoracoscopically resected. In one case it was not possible to deflate the lung sufficiently. The sonic intensity of the probes was between 5 and 7.5 MHz. Both frequencies are ideal for locating the tumours. Intrathoracic manipulation of the probes still poses a problem. We have now constructed a casing for the ultrasonic probe which can be controlled extrathoracically. Resection of peripheral tumours, about 50% of which are benign, is already a domain of thoracoscopic surgery. However, approximately 40% of these tumours cannot be localized and thoracoscopically removed using the usual instruments. We demonstrate that thoracoscopic resection is possible for the majority of these tumours with the use of intrathoracic ultrasound.