Ultrasonography of the Mediastinum: Techniques, Current Practice, and Future Directions

In the everyday practice of respiratory physicians, ultrasound techniques play a key role by enabling\r\nseveral diagnostic and interventional procedures. The application of ultrasound to endoscopic\r\nprocedures allows both a visualization and a guided sampling of mediastinal and hilar lymph\r\nnodes. Endobronchial ultrasound can be combined with transbronchial needle aspiration, and,\r\nsimilarly, endoscopic ultrasound can be combined with fine-needle aspiration to sample virtually all\r\nmediastinal nodal stations from the airways and the esophagus. Endobronchial ultrasound–transbronchial\r\nneedle aspiration and endoscopic ultrasound–fine needle aspiration showed a complementary\r\ndiagnostic yield, and, recently, endoscopic ultrasound with bronchoscope was introduced\r\nin clinical practice to perform a transesophageal needle aspiration by using an ultrasound bronchoscope.\r\nThis technique allows a single operator to perform both transbronchial and transesophageal\r\nneedle sampling with the same instrument during a single bronchoscopic procedure. Mediastinal\r\nstaging impacts the management of patients affected by lung cancer, and the most recent \r\nguidelines clearly state that endobronchial ultrasound and endoscopic ultrasound should be the\r\ninitial tissue sampling procedure over surgical staging. In addition, endoscopic ultrasound techniques\r\ndemonstrated an excellent yield in diagnosing lymphoma and benign diseases, for example,\r\nsarcoidosis. The aim of this review was to discuss the current role and future perspectives of\r\nendosonography techniques available for the evaluation of the mediastinum. Special emphasis was\r\nplaced on equipment and technical aspects, the diagnostic role, and future directions of development.