Ultrasound-guided endoscopic surgery

Ten years' development of sectorial linear endoscopic ultrasound (EUS) has allowed us to perform guided biopsies of lymph nodes, mediastinal masses and pancreatic tumours. Furthermore, biopsy guided by EUS has been the first step in the development of interventional EUS. This development, in turn, has been made possible by the appearance of the interventional echoendoscope with a large working channel. EUS-guided biopsy obtains the best results for lymph nodes, anastomotic relapses and extrinsicz compression as well as for pancreatic tumours. Results in the literature show a global sensitivity of the technique that varies between 76 and 91%, a specificity of 84-100% and an accuracy of 78-94%. Using alcohol injection of the plexus nerves, the coeliac block guided by EUS is a simple technique. It will replace percutaneous access under US or CT scan guidance. Data from the literature show a significant reduction in pain of the order of 85-90% of cases-results that would have been good for percutaneous techniques. The technique of cystoenterostomy guided by EUS allows more accurate drainage of the cysts with a lower risk of perforation and haemorrhage. With regard to haemorrhage it should be emphasized that colour Doppler and power Doppler assessment of the punctures rules out the risk of vascular perforation during puncture but the risk of haemorrhage due to decompression of a vascular lesion in the vicinity of the cyst remains. The new ultrasound echoendoscope EG 38X, with a large working channel (3.8 mm), is now available. This system allows more effective drainage and also enables the placement of cystodigestive stents.