Bihilar lymphadenopathy

BHL. This patient had sarcoidosis – there is marked enlargement of both hila due to lymphadenopathy (arrows), however the lungs are normal. Hilar enlargement can be a difficult call to make on the basis of a CXR, and can be mimicked by patient rotation, however a good rule of thumb is to remember that the lateral margins of the hila should be concave – in this case, you can appreciate that they are convex (especially on the left).