ABSTRACT
Transthoracic ultrasound (US) has become an important diagnostic tool in modern chest medicine. The range of thoracic lesions for which transthoracic US may yield useful diagnostic information has expanded to include not only chest wall and pleural lesions, but also peripheral lung nodules, pulmonary consolidations, necrotizing pneumonias and lung abscesses, tumors with obstructive pneumonitis, mediastinal masses, and peridiaphragmatic lesions. A variety of ultrasound features and signs of chest diseases have been well characterized and widely applied in clinical practice. US guidance increases the diagnostic success rate and decreases the complications associated with interventional procedures such as thoracentesis, closed tube drainage for pleural effusion, and needle biopsy of the pleura. Transthoracic needle aspiration or biopsy, under real-time US guidance, is a relatively safe and easy procedure, and may provide adequate tissue sampling of lesions for cytologic, histologic or microbiologic analysis. This article presents the general techniques and wide applications of transthoracic US and US-guided invasive procedures in the diagnosis and management of various chest diseases.