CT of thoracic lymph nodes. Part I: anatomy and drainage.

CT is the primary non-invasive technique for the diagnostic evaluation of thoracic lymph nodes. The CT patterns and anatomic location of thoracic lymph node involvement can provide important clues in the diagnosis of many diseases. Part I of the pictorial review illustrates the anatomic location and drainage of thoracic lymph nodes in the chest wall, mediastinum and lungs through examples of pathologic involvement. Part II of the pictorial review focuses on CT patterns of lymph node involvement in various pulmonary and extrapulmonary diseases, differential diagnoses based on CT findings and pitfalls.